WorldWideScience

Sample records for modeling stormwater runoff

  1. Model based monitoring of stormwater runoff quality

    DEFF Research Database (Denmark)

    Birch, Heidi; Vezzaro, Luca; Mikkelsen, Peter Steen

    2012-01-01

    Monitoring of micropollutants (MP) in stormwater is essential to evaluate the impacts of stormwater on the receiving aquatic environment. The aim of this study was to investigate how different strategies for monitoring of stormwater quality (combination of model with field sampling) affect...... the information obtained about MPs discharged from the monitored system. A dynamic stormwater quality model was calibrated using MP data collected by volume-proportional and passive sampling in a storm drainage system in the outskirts of Copenhagen (Denmark) and a 10-year rain series was used to find annual...

  2. Model based monitoring of stormwater runoff quality

    DEFF Research Database (Denmark)

    Birch, Heidi; Vezzaro, Luca; Mikkelsen, Peter Steen

    2012-01-01

    the information obtained about MPs discharged from the monitored system. A dynamic stormwater quality model was calibrated using MP data collected by volume-proportional and passive sampling in a storm drainage system in the outskirts of Copenhagen (Denmark) and a 10-year rain series was used to find annual......) for calibration of the model resulted in the same predicted level but narrower model prediction bounds than calibrations based on volume-proportional samples, allowing a better exploitation of the resources allocated for stormwater quality management.......Monitoring of micropollutants (MP) in stormwater is essential to evaluate the impacts of stormwater on the receiving aquatic environment. The aim of this study was to investigate how different strategies for monitoring of stormwater quality (combination of model with field sampling) affect...

  3. Event-based stormwater management pond runoff temperature model

    Science.gov (United States)

    Sabouri, F.; Gharabaghi, B.; Sattar, A. M. A.; Thompson, A. M.

    2016-09-01

    Stormwater management wet ponds are generally very shallow and hence can significantly increase (about 5.4 °C on average in this study) runoff temperatures in summer months, which adversely affects receiving urban stream ecosystems. This study uses gene expression programming (GEP) and artificial neural networks (ANN) modeling techniques to advance our knowledge of the key factors governing thermal enrichment effects of stormwater ponds. The models developed in this study build upon and compliment the ANN model developed by Sabouri et al. (2013) that predicts the catchment event mean runoff temperature entering the pond as a function of event climatic and catchment characteristic parameters. The key factors that control pond outlet runoff temperature, include: (1) Upland Catchment Parameters (catchment drainage area and event mean runoff temperature inflow to the pond); (2) Climatic Parameters (rainfall depth, event mean air temperature, and pond initial water temperature); and (3) Pond Design Parameters (pond length-to-width ratio, pond surface area, pond average depth, and pond outlet depth). We used monitoring data for three summers from 2009 to 2011 in four stormwater management ponds, located in the cities of Guelph and Kitchener, Ontario, Canada to develop the models. The prediction uncertainties of the developed ANN and GEP models for the case study sites are around 0.4% and 1.7% of the median value. Sensitivity analysis of the trained models indicates that the thermal enrichment of the pond outlet runoff is inversely proportional to pond length-to-width ratio, pond outlet depth, and directly proportional to event runoff volume, event mean pond inflow runoff temperature, and pond initial water temperature.

  4. Stormwater runoff - modeling impacts of urbanization and climate change

    OpenAIRE

    Blair, Anne; Sanger, Denise; Holland, Frderick; White, David; Vandiver, Lisa; White, Susan

    2010-01-01

    Development pressure throughout the coastal areas of the United States continues to build, particularly in the southeast (Allen and Lu 2003, Crossett et al. 2004). It is well known that development alters watershed hydrology: as land becomes covered with surfaces impervious to rain, water is redirected from groundwater recharge and evapotranspiration to stormwater runoff, and as the area of impervious cover increases, so does the volume and rate of runoff (Schueler 1994, Corbett et al. 1997)....

  5. Model-based monitoring of stormwater runoff quality

    DEFF Research Database (Denmark)

    Birch, Heidi; Vezzaro, Luca; Mikkelsen, Peter Steen

    2013-01-01

    Monitoring of micropollutants (MP) in stormwater is essential to evaluate the impacts of stormwater on the receiving aquatic environment. The aim of this study was to investigate how different strategies for monitoring of stormwater quality (combining a model with field sampling) affect...... the information obtained about MP discharged from the monitored system. A dynamic stormwater quality model was calibrated using MP data collected by automatic volume-proportional sampling and passive sampling in a storm drainage system on the outskirts of Copenhagen (Denmark) and a 10-year rain series was used......) for calibration of the model, resulted in the same predicted level but with narrower model prediction bounds than by using volume-proportional samples for calibration. This shows that passive sampling allows for a better exploitation of the resources allocated for stormwater quality monitoring....

  6. Physical design optimization of an urban runoff treatment system using Stormwater Management Model (SWMM).

    Science.gov (United States)

    Tobio, J A S; Maniquiz-Redillas, M C; Kim, L H

    2015-01-01

    The study presented the application of Stormwater Management Model (SWMM) in determining the optimal physical design properties of an established low impact development (LID) system treating road runoff. The calibration of the model was based on monitored storm events occurring from May 2010 to July 2013. It was found that the total suspended solids was highly correlated with stormwater runoff volume and dominant heavy metal constituents in stormwater runoff, such lead, zinc and copper, with a Pearson correlation coefficient ranging from 0.88 to 0.95 (P<0.05). Reducing the original ratio of the storage volume to surface area (SV/SA) of the facility and depth by 25% could match the satisfactory performance efficiency achieved in the original design. The smaller SV/SA and depth would mean a less costly system, signifying the importance of optimization in designing LID systems.

  7. Application Of Global Sensitivity Analysis And Uncertainty Quantification In Dynamic Modelling Of Micropollutants In Stormwater Runoff

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen

    2012-01-01

    . The analysis is based on the combination of variance-decomposition Global Sensitivity Analysis (GSA) with the Generalized Likelihood Uncertainty Estimation (GLUE) technique. The GSA-GLUE approach highlights the correlation between the model factors defining the mass of pollutant in the system......The need for estimating micropollutants fluxes in stormwater systems increases the role of stormwater quality models as support for urban water managers, although the application of such models is affected by high uncertainty. This study presents a procedure for identifying the major sources...... of uncertainty in a conceptual lumped dynamic stormwater runoff quality model that is used in a study catchment to estimate (i) copper loads, (ii) compliance with dissolved Cu concentration limits on stormwater discharge and (iii) the fraction of Cu loads potentially intercepted by a planned treatment facility...

  8. Phytoremediation of nutrient polluted stormwater runoff: water hyacinth as a model plant

    NARCIS (Netherlands)

    Fox, L.J.

    2009-01-01

    Het doel van het in dit proefschrift beschreven onderzoek was om te verkennen in hoeverre fytoremediatie met behulp van waterplanten kon beheersen en de waterkwaliteit te verbeterenPhytoremediation of nutriënt polluted stormwater runoff using water hyacinth as a model plant was explored in greenhous

  9. Assessing the polycyclic aromatic hydrocarbon (PAH) pollution of urban stormwater runoff: a dynamic modeling approach.

    Science.gov (United States)

    Zheng, Yi; Lin, Zhongrong; Li, Hao; Ge, Yan; Zhang, Wei; Ye, Youbin; Wang, Xuejun

    2014-05-15

    Urban stormwater runoff delivers a significant amount of polycyclic aromatic hydrocarbons (PAHs), mostly of atmospheric origin, to receiving water bodies. The PAH pollution of urban stormwater runoff poses serious risk to aquatic life and human health, but has been overlooked by environmental modeling and management. This study proposed a dynamic modeling approach for assessing the PAH pollution and its associated environmental risk. A variable time-step model was developed to simulate the continuous cycles of pollutant buildup and washoff. To reflect the complex interaction among different environmental media (i.e. atmosphere, dust and stormwater), the dependence of the pollution level on antecedent weather conditions was investigated and embodied in the model. Long-term simulations of the model can be efficiently performed, and probabilistic features of the pollution level and its risk can be easily determined. The applicability of this approach and its value to environmental management was demonstrated by a case study in Beijing, China. The results showed that Beijing's PAH pollution of road runoff is relatively severe, and its associated risk exhibits notable seasonal variation. The current sweeping practice is effective in mitigating the pollution, but the effectiveness is both weather-dependent and compound-dependent. The proposed modeling approach can help identify critical timing and major pollutants for monitoring, assessing and controlling efforts to be focused on. The approach is extendable to other urban areas, as well as to other contaminants with similar fate and transport as PAHs.

  10. Modeling and Management of Increased Urban Stormwater Runoff Using InfoSWMM Sustain in the Berkeley Neighborhood of Denver, Colorado

    Science.gov (United States)

    Panos, C.; Hogue, T. S.; McCray, J. E.

    2016-12-01

    Few urban studies have evaluated the hydrologic impacts of redevelopment - for example, a rapid conversion from single to multi-family homes - known as infill, or re-urbanization. Redevelopment provides unique stormwater challenges as private property owners in many cities are not mandated to undertake stormwater retrofits leading to an overall increase in stormwater quantity and decrease in quality. This research utilizes a version of the EPA's Storm Water Management Model (SWMM), InfoSWMM Sustain, to model and analyze the impacts of impervious cover change due to redevelopment on stormwater quantity and quality in Denver, Colorado, with a focus on the Berkeley Neighborhood, where the percent imperviousness is expected to increase significantly from a current value of 53% by 2025. We utilize flow data from multiple pressure transducers installed directly within the storm sewer network as well as water quality data from storm and low flow sampling to initially calibrate InfoSWMM Sustain using September 2015 through September 2016 storm data. Model scenarios include current land cover conditions as well as future imperviousness predictions from redevelopment. The Urban Drainage and Flood Control District's Colorado Urban Hydrograph Procedure (CUHP) model is also implemented and used for calibration and comparison to the InfoSWMM stormwater model. Model simulations predicting an average annual stormwater runoff for the basin will be used to inform stormwater capture for the Berkeley Neighborhood on the downstream Willis Case Golf Course, where treatment trains are being designed to provide irrigation water (a 250 ac-ft per year demand) and improved water quality for discharge to the nearby receiving waters of Clear Creek. Ultimately, study results will better inform regional stormwater capture requirements when transitioning from single to multi-family units by providing a quantitative basis for treatment and regulation priorities.

  11. Green Roofs for Stormwater Runoff Control - Abstract

    Science.gov (United States)

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  12. Modeling the eutrophication of two mature planted stormwater ponds for runoff control

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, A.H.; Hvitved-Jacobsen, Thorkild

    2013-01-01

    A model, targeting eutrophication of stormwater detention ponds was developed and applied to sim-ulate pH, dissolved oxygen and the development of algae and plant biomass in two mature plantedwetponds for run off control. The model evaluated algal and plant biomass growth into three groupsnamely;...

  13. How uncertain is model-based prediction of copper loads in stormwater runoff?

    DEFF Research Database (Denmark)

    Lindblom, Erik Ulfson; Ahlman, S.; Mikkelsen, Peter Steen

    2007-01-01

    In this paper, we conduct a systematic analysis of the uncertainty related with estimating the total load of pollution (copper) from a separate stormwater drainage system, conditioned on a specific combination of input data, a dynamic conceptual pollutant accumulation-washout model and measurements...

  14. Influence factors and prediction of stormwater runoff of urban green space in Tianjin, China: laboratory experiment and quantitative theory model.

    Science.gov (United States)

    Yang, Xu; You, Xue-Yi; Ji, Min; Nima, Ciren

    2013-01-01

    The effects of limiting factors such as rainfall intensity, rainfall duration, grass type and vegetation coverage on the stormwater runoff of urban green space was investigated in Tianjin. The prediction equation of stormwater runoff was established by the quantitative theory with the lab experimental data of soil columns. It was validated by three field experiments and the relative errors between predicted and measured stormwater runoff are 1.41, 1.52 and 7.35%, respectively. The results implied that the prediction equation could be used to forecast the stormwater runoff of urban green space. The results of range and variance analysis indicated the sequence order of limiting factors is rainfall intensity > grass type > rainfall duration > vegetation coverage. The least runoff of green land in the present study is the combination of rainfall intensity 60.0 mm/h, duration 60.0 min, grass Festuca arundinacea and vegetation coverage 90.0%. When the intensity and duration of rainfall are 60.0 mm/h and 90.0 min, the predicted volumetric runoff coefficient is 0.23 with Festuca arundinacea of 90.0% vegetation coverage. The present approach indicated that green space is an effective method to reduce stormwater runoff and the conclusions are mainly applicable to Tianjin and the semi-arid areas with main summer precipitation and long-time interval rainfalls.

  15. Green Roofs for Stormwater Runoff Control

    Science.gov (United States)

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  16. Simulation of stormwater quality in an urban catchment using the Stormwater Management Model (SWMM)

    OpenAIRE

    2014-01-01

    In the face of climate change, population growth and urbanization an understanding of stormwater quality processes and their prediction in urban areas are essential to make good use of stormwater and to minimize its detrimental impacts on the population and the environment. In this study a stormwater quality model calibration was conducted using the Stormwater Management Model (SWMM) for an urban catchment in Lahti, Finland by utilizing rainfall, runoff and turbidity data from the catchme...

  17. APPROACHES FOR DETERMINING SWALE PERFORMANCE FOR STORMWATER RUNOFF - Wilmington, NC

    Science.gov (United States)

    Swales are “engineered vegetated ditches” that provide stable routing for stormwater runoff and a low-cost drainage option for highways, farms, industrial sites, and commercial areas. It is reported in the literature that swales mitigate runoff-carried pollutants, reduce runoff ...

  18. APPROACHES FOR DETERMINING SWALE PERFORMANCE FOR STORMWATER RUNOFF

    Science.gov (United States)

    Swales are “engineered vegetated ditches” that provide stable routing for stormwater runoff and a low-cost drainage option for highways, farms, industrial sites, and commercial areas. It is reported in the literature that swales mitigate runoff-carried pollutants, reduce runoff v...

  19. Passive sampling and modeling of PAHs and heavy metals in stormwater runoff

    DEFF Research Database (Denmark)

    Birch, Heidi; Sharma, Anitha Kumari; Vezzaro, Luca

    2011-01-01

    Requirements in the European Water Framework Directive include monitoring of priority substances in the aquatic environment. Use of passive samplers for monitoring purposes in the highly dynamic storm sewer systems is limited by the time-proportional sampling adopted by the majority...... of the available samplers. This paper reports the preliminary results from work with the SorbiCell passive sampler, which samples runoff with a velocity-proportional approach. The inlet and outlet of a retention pond was monitored by using autosamplers and SorbiCell passive samplers. Total concentrations of PAHs...... in samples from the autosampler ranged from LOD - 0.63 μg/L in the pond inlet and LOD - 0.08 μg/L in the outlet. Dissolved concentrations of PAHs measured using the passive samplers at the inlet varied from LOD - 0.93 μg/L. Dissolved copper concentrations ranged from 4.7-22 μg/L according to the data from...

  20. Stormwater Runoff: What it is and Why it is Important in Johnson County, Kansas

    Science.gov (United States)

    Rasmussen, Teresa J.; Schmidt, Heather C.

    2009-01-01

    Stormwater runoff is a leading contributor to pollution in streams, rivers, and lakes in Johnson County, Kansas, and nationwide. Because stormwater runoff contains pollutants from many different sources, decreasing pollution from stormwater runoff is a challenging task. It requires cooperation from residents, businesses, and municipalities. An important step in protecting streams from stormwater pollution is understanding watershed processes, stormwater characteristics, and their combined effects on streams and water quality.

  1. Influence of land development on stormwater runoff from a mixed land use and land cover catchment.

    Science.gov (United States)

    Paule-Mercado, M A; Lee, B Y; Memon, S A; Umer, S R; Salim, I; Lee, C-H

    2017-12-01

    Mitigating for the negative impacts of stormwater runoff is becoming a concern due to increased land development. Understanding how land development influences stormwater runoff is essential for sustainably managing water resources. In recent years, aggregate low impact development-best management practices (LID-BMPs) have been implemented to reduce the negative impacts of stormwater runoff on receiving water bodies. This study used an integrated approach to determine the influence of land development and assess the ecological benefits of four aggregate LID-BMPs in stormwater runoff from a mixed land use and land cover (LULC) catchment with ongoing land development. It used data from 2011 to 2015 that monitored 41 storm events and monthly LULC, and a Personalized Computer Storm Water Management Model (PCSWMM). The four aggregate LID-BMPs are: ecological (S1), utilizing pervious covers (S2), and multi-control (S3) and (S4). These LID-BMPs were designed and distributed in the study area based on catchment characteristics, cost, and effectiveness. PCSWMM was used to simulate the monitored storm events from 2014 (calibration: R(2) and NSE>0.5; RMSE 0.5; RMSE land and impervious cover, soil alteration, and high amount of precipitation influenced the stormwater runoff variability during different phases of land development. The four aggregate LID-BMPs reduced runoff volume (34%-61%), peak flow (6%-19%), and pollutant concentrations (53%-83%). The results of this study, in addition to supporting local LULC planning and land development activities, also could be applied to input data for empirical modeling, and designing sustainable stormwater management guidelines and monitoring strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Statistics for stochastic modeling of volume reduction, hydrograph extension, and water-quality treatment by structural stormwater runoff best management practices (BMPs)

    Science.gov (United States)

    Granato, Gregory E.

    2014-01-01

    The U.S. Geological Survey (USGS) developed the Stochastic Empirical Loading and Dilution Model (SELDM) in cooperation with the Federal Highway Administration (FHWA) to indicate the risk for stormwater concentrations, flows, and loads to be above user-selected water-quality goals and the potential effectiveness of mitigation measures to reduce such risks. SELDM models the potential effect of mitigation measures by using Monte Carlo methods with statistics that approximate the net effects of structural and nonstructural best management practices (BMPs). In this report, structural BMPs are defined as the components of the drainage pathway between the source of runoff and a stormwater discharge location that affect the volume, timing, or quality of runoff. SELDM uses a simple stochastic statistical model of BMP performance to develop planning-level estimates of runoff-event characteristics. This statistical approach can be used to represent a single BMP or an assemblage of BMPs. The SELDM BMP-treatment module has provisions for stochastic modeling of three stormwater treatments: volume reduction, hydrograph extension, and water-quality treatment. In SELDM, these three treatment variables are modeled by using the trapezoidal distribution and the rank correlation with the associated highway-runoff variables. This report describes methods for calculating the trapezoidal-distribution statistics and rank correlation coefficients for stochastic modeling of volume reduction, hydrograph extension, and water-quality treatment by structural stormwater BMPs and provides the calculated values for these variables. This report also provides robust methods for estimating the minimum irreducible concentration (MIC), which is the lowest expected effluent concentration from a particular BMP site or a class of BMPs. These statistics are different from the statistics commonly used to characterize or compare BMPs. They are designed to provide a stochastic transfer function to approximate

  3. Using Economic Incentives to Manage Stormwater Runoff in the Shepherd Creek Watershed, Part I

    Science.gov (United States)

    Communities nationwide are facing increased responsibility for controlling stormwater runoff, and, subsequently, rising costs of stormwater management. In this report we describe and test a methodology that can be used by communities to focus limited budgets on the most efficien...

  4. Soil amendments for heavy metals removal from stormwater runoff discharging to environmentally sensitive areas

    Science.gov (United States)

    Trenouth, William R.; Gharabaghi, Bahram

    2015-10-01

    Concentrations of dissolved metals in stormwater runoff from urbanized watersheds are much higher than established guidelines for the protection of aquatic life. Five potential soil amendment materials derived from affordable, abundant sources have been tested as filter media using shaker tests and were found to remove dissolved metals in stormwater runoff. Blast furnace (BF) slag and basic oxygenated furnace (BOF) slag from a steel mill, a drinking water treatment residual (DWTR) from a surface water treatment plant, goethite-rich overburden (IRON) from a coal mine, and woodchips (WC) were tested. The IRON and BOF amendments were shown to remove 46-98% of dissolved metals (Cr, Co, Cu, Pb, Ni, Zn) in repacked soil columns. Freundlich adsorption isotherm constants for six metals across five materials were calculated. Breakthrough curves of dissolved metals and total metal accumulation within the filter media were measured in column tests using synthetic runoff. A reduction in system performance over time occurred due to progressive saturation of the treatment media. Despite this, the top 7 cm of each filter media removed up to 72% of the dissolved metals. A calibrated HYDRUS-1D model was used to simulate long-term metal accumulation in the filter media, and model results suggest that for these metals a BOF filter media thickness as low as 15 cm can be used to improve stormwater quality to meet standards for up to twenty years. The treatment media evaluated in this research can be used to improve urban stormwater runoff discharging to environmentally sensitive areas (ESAs).

  5. Nitrogen removal from urban stormwater runoff through layered bioretention columns.

    Science.gov (United States)

    Hsieh, Chi-hsu; Davis, Allen P; Needelman, Brian A

    2007-11-01

    Bioretention is a low-impact technology used for the treatment of stormwater runoff in developed areas. The fates of mineral nitrogen compounds in two bioretention columns (RP1 and RP2) with different media-layering characteristics were investigated under multiple loadings of simulated urban runoff. The immediate capture of nitrogen was evaluated, with nitrogen transformation reactions that occurred during the drying periods between rainfall events. A greater proportion of ammonium was removed from runoff in RP2 (68 +/- 16%), which had a high permeability layer over a lower permeability layer, than in RP1 (12 +/- 6%), which had the inverse configuration. Both column systems demonstrated nitrate export (9 +/- 32% and 54 +/- 22% greater than input for RP1 and RP2, respectively), attributed to washout of nitrate resulting from nitrification processes between runoff loading events. Bioretention media with a less permeable bottom soil layer could form an anoxic/anaerobic zone for promoting nitrification/denitrification processes.

  6. Data for and adjusted regional regression models of volume and quality of urban storm-water runoff in Boise and Garden City, Idaho, 1993-94

    Science.gov (United States)

    Kjelstrom, L.C.

    1995-01-01

    The U.S. Environmental Protection Agency requires information on the volume and quality of urban storm-water runoff to apply for a permit to discharge this water into the Boise River under the National Pollutant Discharge Elimination System Program. Concentrations of selected chemical constituents in storm runoff were determined from samples collected at four storm-sewer outfalls in Boise from October 1993 through June 1994 and at one outfall in Garden City from September through October 1994. Samples were analyzed for specific conductance, pH, alkalinity, water temperature, oxygen demand, fecal indicator bacteria, major ions, dissolved and suspended solids, nutrients, trace elements, and numerous organic compounds. The measurement of storm-runoff volume and mean concentrations of constituents were used to estimate storm-runoff loads.

  7. Engineered bioretention for removal of nitrate from stormwater runoff.

    Science.gov (United States)

    Kim, Hunho; Seagren, Eric A; Davis, Allen P

    2003-01-01

    A bioretention unit is a simple, plant- and soil-based, low-impact treatment and infiltration facility for treating stormwater runoff in developed areas. Nitrate, however, is not attenuated in conventional bioretention facilities. Thus, this study systematically evaluated a reengineered concept of bioretention for nitrate removal via microbial denitrification, which incorporates a continuously submerged anoxic zone with an overdrain. Experimental studies were performed in four phases. In the first two phases, column studies demonstrated that, overall, newspaper is the best solid-phase electron-donor substrate for denitrification out of the set studied (alfalfa, leaf mulch compost, newspaper, sawdust, wheat straw, wood chips, and elemental sulfur) based on superior nitrate removal and effluent water quality. The nitrate loading and hydraulic loading studies in the second phase provided design information. In the third phase, system viability after 30- and 84-day dormant periods was evaluated in column studies, demonstrating that newspaper-supported biological denitrification should be effective under conditions of intermittent loadings. Finally, in the fourth phase, pilot-scale bioretention studies demonstrated the effectiveness of the proposed design, showing nitrate plus nitrite mass removals of up to 80%. These results indicate that engineered bioretention for the removal of nitrogen from stormwater runoff has the potential for successful application as an urban stormwater treatment practice.

  8. Determination of copper speciation in highway stormwater runoff using competitive ligand exchange - Adsorptive cathodic stripping voltammetry.

    Science.gov (United States)

    Nason, Jeffrey A; Sprick, Matthew S; Bloomquist, Don J

    2012-11-01

    Low concentrations of dissolved copper have been shown to adversely affect the olfactory system of salmonid species, impairing their ability to avoid predators and likely increasing mortality. These studies have resulted in increased regulatory scrutiny of stormwater discharges to surface waters inhabited by threatened and endangered salmonid species. Because it is primarily the free ionic (Cu(2+)) and weakly complexed forms of copper that are bioavailable, it is critical to understand the speciation of copper in stormwater. This paper reports on the characterization of copper binding ligands and copper speciation in composite samples of highway stormwater runoff collected at four sites in Oregon, USA using competitive ligand exchange - adsorptive cathodic stripping voltammetry (CLE-ACSV). Although the concentration and strength of copper binding ligands in stormwater varied considerable between sites and storms, the vast majority (>99.9%) of the total dissolved copper in composite samples was complexed by organic ligands in stormwater. Although total dissolved copper concentrations range from 2 to 20 μg/L, the analytically determined free ionic copper concentrations did not exceed 10(-10) M (6.3 ng/L) in any of the fully characterized samples, suggesting that much of the copper in highway stormwater is not bioavailable. Analytically determined free ionic copper concentrations were compared with those predicted by a readily available chemical equilibrium models and found to be in reasonable agreement. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Integrated modelling of Priority Pollutants in stormwater systems

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Ledin, Anna; Mikkelsen, Peter Steen

    2012-01-01

    The increasing focus on urban diffuse sources of Priority Pollutants (PPs) has highlighted stormwater as an important contributor to contamination of natural water bodies. This study presents an example of an integrated model developed to be able to quantify PP loads discharged by stormwater...... systems. The integrated model includes three submodels that simulate (a) stormwater pollutant sources in the catchments, (b) runoff quality and quantity and (c) stormwater treatment. These submodels employ all the generic available information that can be retrieved without extensive on-site data...... collection campaigns. Given the general lack of data regarding stormwater PPs and the inherent uncertainty of stormwater quality models, the Generalized Likelihood Uncertainty Estimation (GLUE) technique was applied to estimate the results’ uncertainty. The integrated model was used to estimate the total...

  10. Biodegradability and Molecular Composition of Dissolved Organic Nitrogen in Urban Stormwater Runoff and Outflow Water from a Stormwater Retention Pond.

    Science.gov (United States)

    Lusk, Mary G; Toor, Gurpal S

    2016-04-01

    Dissolved organic nitrogen (DON) can be a significant part of the reactive N in aquatic ecosystems and can accelerate eutrophication and harmful algal blooms. A bioassay method was coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to determine the biodegradability and molecular composition of DON in the urban stormwater runoff and outflow water from an urban stormwater retention pond. The biodegradability of DON increased from 10% in the stormwater runoff to 40% in the pond outflow water and DON was less aromatic and had lower overall molecular weight in the pond outflow water than in the stormwater runoff. More than 1227 N-bearing organic formulas were identified with FT-ICR-MS in the stormwater runoff and pond outflow water, which were only 13% different in runoff and outflow water. These molecular formulas represented a wide range of biomolecules such as lipids, proteins, amino sugars, lignins, and tannins in DON from runoff and pond outflow water. This work implies that the urban infrastructure (i.e., stormwater retention ponds) has the potential to influence biogeochemical processes in downstream water bodies because retention ponds are often a junction between the natural and the built environment.

  11. Bioretention column studies of phosphorus removal from urban stormwater runoff.

    Science.gov (United States)

    Hsieh, Chi-hsu; Davis, Allen P; Needelman, Brian A

    2007-02-01

    This study investigated the effectiveness of bioretention as a stormwater management practice using repetitive bioretention columns for phosphorus removal. Bioretention media, with a higher short-term phosphorus sorption capacity, retained more phosphorus from infiltrating runoff after 3 mg/L phosphorus loading. A surface mulch layer prevented clogging after repetitive total suspended solids input. Evidence suggests that long-term phosphorus reactions will regenerate active short-term phosphorus adsorption sites. A high hydraulic conductivity media overlaying one with low hydraulic conductivity resulted in a higher runoff infiltration rate, from 0.51 to 0.16 cm/min at a fixed 15-cm head, and was more efficient in phosphorus removal (85% mass removal) than a profile with low conductivity media over high (63% mass removal). Media extractions suggest that most of the retained phosphorus in the media layers is available for vegetative uptake and that environmental risk thresholds were not exceeded.

  12. Ecological risk assessment of zinc from stormwater runoff to an aquatic ecosystem.

    Science.gov (United States)

    Brix, Kevin V; Keithly, James; Santore, Robert C; DeForest, David K; Tobiason, Scott

    2010-03-15

    Zinc (Zn) risks from stormwater runoff to an aquatic ecosystem were studied. Monitoring data on waterborne, porewater, and sediment Zn concentrations collected at 20 stations throughout a stormwater collection/detention facility consisting of forested wetlands, a retention pond and first order stream were used to conduct the assessment. Bioavailability in the water column was estimated using biotic ligand models for invertebrates and fish while bioavailability in the sediment was assessed using acid volatile sulfide-simultaneously extracted metal (AVS-SEM). The screening level assessment indicated no significant risks were posed to benthic organisms from Zn concentrations in sediments and pore water. As would be expected for stormwater, Zn concentrations were temporally quite variable within a storm event, varying by factors of 2 to 4. Overall, probabilistic assessment indicated low (5-10% of species affected) to negligible risks in the system, especially at the discharge to the first order stream. Moderate to high risks (10-50% of species affected) were identified at sampling locations most upgradient in the collection system. The largest uncertainty with the assessment is associated with how best to estimate chronic exposure/risks from time-varying exposure concentrations. Further research on pulse exposure metal toxicity is clearly needed to assess stormwater impacts on the environment.

  13. Use of modified pine bark for removal of pesticides from stormwater runoff

    Science.gov (United States)

    Mandla A. Tshabalala

    2003-01-01

    Pesticide entrainment in stormwater runoff can contribute to non-point source pollution of surface waters. Granular activated carbon has been successfully used for removing pesticides from wastewater. However, implementation of granular activated carbon sorption media in stormwater filtration systems comes with high initial capital investment and operating costs....

  14. SHEPHERD CREEK, CINCINNATI, OH: USING TRADABLE CREDITS TO CONTROL EXCESS STORMWATER RUNOFF

    Science.gov (United States)

    The problem of managing stormwater runoff grows apace with continued urbanization, yet the management tools for this growing non-point source problem have not fully kept up. The rapid growth of stormwater utilities around the nation is an important step toward providing an ef...

  15. Stormwater Runoff and Associated Sediment Contamination in the Pond C Watershed, Minnesota Valley National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A nearshore area of Long Meadow Lake on the Minnesota Valley National Wildlife Refuge receiving stormwater runoff from a 2600-acre urban watershed was found in 1988...

  16. [Research on spatial differentiation of urban stormwater runoff quality by source area monitoring].

    Science.gov (United States)

    Li, Li-Qing; Zhu, Ren-Xiao; Guo, Shu-Gang; Yin, Cheng-Qing

    2010-12-01

    Runoff samples were collected from 14 source areas in Hanyang district during four rain events in an attempt to investigate the spatial differentiation and influencing factors of urban stormwater runoff quality. The outcomes are expected to offer practical guidance in sources control of urban runoff pollution. The results revealed that particle-bound proportion of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in stormwater runoff were 58% +/- 17%, 65% +/- 13% and 92% +/- 6%, respectively. The fractions of ammonia, nitrate and dissolved organic nitrogen were homogeneous in dissolved nitrogen composition. Urban surface function, traffic volume, land use, population density, and street sweeping practice are the main factors determining spatial differentiation of urban surface runoff quality. The highest magnitude of urban stormwater runoff pollution was expected in the old urban residential area, followed by general residential with restaurants, commercial and transport area, new developments and green land. In addition, the magnitude of road stormwater runoff pollution is positively correlated to traffic volume, in the following order: the first trunk road > the second trunk road > minor road. Street sweeping and critical source areas controls should be implemented to mitigate the adverse effects of urban stormwater runoff on receive waters.

  17. Check dam and polyacrylamide performance under simulated stormwater runoff.

    Science.gov (United States)

    Kang, Jihoon; McCaleb, Melanie M; McLaughlin, Richard A

    2013-11-15

    High levels of turbidity and fine suspended sediments are often found in stormwater discharges from construction sites even when best management practices (BMPs) for sediment control are in place. This study evaluated turbidity reduction by three check dam types: 1) rock check dam representing a standard BMP, 2) excelsior wattle representing a fiber check dam (FCD), and 3) rock check dam wrapped with excelsior erosion control blanket (rock + excelsior ECB) representing an alternative FCD. Three check dams (all same type) were installed in a lined, 24-m ditch on a 5-7% slope and three consecutive simulated stormwater flows were run in the ditch. Additional tests were performed by adding granular polyacrylamide (PAM) on the check dams in the same manner using two sediment sources differing in clay content. Without PAM treatment, significantly higher effluent turbidity (>900 nephelometric turbidity units (NTU)) exited the ditch with rock check dams than with excelsior wattles or rock + excelsior ECBs (dam types was in the order of excelsior wattle > rock + excelsior ECB > rock check dam, indicating better water pooling behind the wattle. The PAM treatment reduced turbidity substantially (>75% relative to no PAM treatment) for all check dam types and it was very effective in excelsior wattles (<57 NTU) and rock + excelsior ECBs (<90 NTU) even during the third storm event. This study demonstrates that the passive treatment of runoff with PAM on FCDs (or rock + excelsior ECB) in construction site ditches can be very effective for sediment retention and turbidity reduction.

  18. Urban Stormwater Management Model and Tools for Designing Stormwater Management of Green Infrastructure Practices

    Science.gov (United States)

    Haris, H.; Chow, M. F.; Usman, F.; Sidek, L. M.; Roseli, Z. A.; Norlida, M. D.

    2016-03-01

    Urbanization is growing rapidly in Malaysia. Rapid urbanization has known to have several negative impacts towards hydrological cycle due to decreasing of pervious area and deterioration of water quality in stormwater runoff. One of the negative impacts of urbanization is the congestion of the stormwater drainage system and this situation leading to flash flood problem and water quality degradation. There are many urban stormwater management softwares available in the market such as Storm Water Drainage System design and analysis program (DRAINS), Urban Drainage and Sewer Model (MOUSE), InfoWorks River Simulation (InfoWork RS), Hydrological Simulation Program-Fortran (HSPF), Distributed Routing Rainfall-Runoff Model (DR3M), Storm Water Management Model (SWMM), XP Storm Water Management Model (XPSWMM), MIKE-SWMM, Quality-Quantity Simulators (QQS), Storage, Treatment, Overflow, Runoff Model (STORM), and Hydrologic Engineering Centre-Hydrologic Modelling System (HEC-HMS). In this paper, we are going to discuss briefly about several softwares and their functionality, accessibility, characteristics and components in the quantity analysis of the hydrological design software and compare it with MSMA Design Aid and Database. Green Infrastructure (GI) is one of the main topics that has widely been discussed all over the world. Every development in the urban area is related to GI. GI can be defined as green area build in the develop area such as forest, park, wetland or floodway. The role of GI is to improve life standard such as water filtration or flood control. Among the twenty models that have been compared to MSMA SME, ten models were selected to conduct a comprehensive review for this study. These are known to be widely accepted by water resource researchers. These ten tools are further classified into three major categories as models that address the stormwater management ability of GI in terms of quantity and quality, models that have the capability of conducting the

  19. SPECIAL ANALYSIS OF OPERATIONAL STORMWATER RUNOFF COVERS OVER SLIT TRENCHES

    Energy Technology Data Exchange (ETDEWEB)

    Collard, L; Luther Hamm, L

    2008-12-18

    Solid Waste Management (SWM) commissioned this Special Analysis (SA) to determine the effects of placing operational stormwater runoff covers (referred to as covers in the remainder of this document) over slit trench (ST) disposal units ST1 through ST7 (the center set of slit trenches). Previously the United States Department of Energy (DOE) entered into an agreement with the United States Environmental Protection Agency (EPA) and the South Carolina Department of Health and Environmental Control (SCDHEC) to place covers over Slit Trenches 1 and 2 to be able to continue disposing Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) solid waste (see USDOE 2008). Because the covers changed the operating conditions, DOE Order 435.1 (DOE 1999) required that an SA be performed to assess the impact. This Special Analysis has been prepared to determine the effects of placing covers over slit trenches at about years 5, 10 and 15 of the 30-year operational period. Because some slit trenches have already been operational for about 15 years, results from analyzing covers at 5 years and 10 years provide trend analysis information only. This SA also examined alternatives of covering Slit Trenches 1 and 2 with one cover and Slit Trenches 3 and 4 with a second cover versus covering them all with a single cover. Based on modeling results, minimal differences exist between covering Slit Trench groups 1-2 and 3-4 with two covers or one large cover. This SA demonstrates that placement of covers over slit trenches will slow the subsequent release and transport of radionuclides in the vadose zone in the early time periods (from time of placement until about 100 years). Release and transport of some radionuclides in the vadose zone beyond 100 years were somewhat higher than for the case without covers. The sums-of-fractions (SOFs) were examined for the current waste inventory in ST1 and ST2 and for estimated inventories at closure for ST3 through ST7. In all

  20. Modelling the Hydraulic Processes on Constructed Stormwater Wetland

    Directory of Open Access Journals (Sweden)

    Isri Ronald Mangangka

    2017-03-01

    Full Text Available Constructed stormwater wetlands are manmade, shallow, and extensively vegetated water bodies which promote runoff volume and peak flow reduction, and also treat stormwater runoff quality. Researchers have noted that treatment processes of runoff in a constructed wetland are influenced by a range of hydraulic factors, which can vary during a rainfall event, and their influence on treatment can also vary as the event progresses. Variation in hydraulic factors during an event can only be generated using a detailed modelling approach, which was adopted in this research by developing a hydraulic conceptual model. The developed model was calibrated using trial and error procedures by comparing the model outflow with the measured field outflow data. The accuracy of the developed model was analyzed using a well-known statistical analysis method developed based on the regression analysis technique. The analysis results show that the developed model is satisfactory.

  1. Predicting urban stormwater runoff with quantitative precipitation estimates from commercial microwave links

    Science.gov (United States)

    Pastorek, Jaroslav; Fencl, Martin; Stránský, David; Rieckermann, Jörg; Bareš, Vojtěch

    2017-04-01

    Reliable and representative rainfall data are crucial for urban runoff modelling. However, traditional precipitation measurement devices often fail to provide sufficient information about the spatial variability of rainfall, especially when heavy storm events (determining design of urban stormwater systems) are considered. Commercial microwave links (CMLs), typically very dense in urban areas, allow for indirect precipitation detection with desired spatial and temporal resolution. Fencl et al. (2016) recognised the high bias in quantitative precipitation estimates (QPEs) from CMLs which significantly limits their usability and, in order to reduce the bias, suggested a novel method for adjusting the QPEs to existing rain gauge networks. Studies evaluating the potential of CMLs for rainfall detection so far focused primarily on direct comparison of the QPEs from CMLs to ground observations. In contrast, this investigation evaluates the suitability of these innovative rainfall data for stormwater runoff modelling on a case study of a small ungauged (in long-term perspective) urban catchment in Prague-Letňany, Czech Republic (Fencl et al., 2016). We compare the runoff measured at the outlet from the catchment with the outputs of a rainfall-runoff model operated using (i) CML data adjusted by distant rain gauges, (ii) rainfall data from the distant gauges alone and (iii) data from a single temporary rain gauge located directly in the catchment, as it is common practice in drainage engineering. Uncertainties of the simulated runoff are analysed using the Bayesian method for uncertainty evaluation incorporating a statistical bias description as formulated by Del Giudice et al. (2013). Our results show that adjusted CML data are able to yield reliable runoff modelling results, primarily for rainfall events with convective character. Performance statistics, most significantly the timing of maximal discharge, reach better (less uncertain) values with the adjusted CML data

  2. Transfer of pesticides and copper in a stormwater wetland receiving contaminated runoff from a vineyard catchment

    Science.gov (United States)

    Maillard, E.; Babcsanyi, I.; Payraudeau, S.; Imfeld, G.

    2012-04-01

    Wetlands can collect contaminated runoff from urban and agricultural catchments, and have intrinsic physical, chemical and biological processes useful for mitigating pesticides. However, knowledge about the ability of wetlands to mitigate pesticide mixtures in runoff is currently very limited. Our results show that stormwater wetlands that primarily serve for flood protection can also be effective tools for reducing concentrations and loads of runoff-related pesticides. Concentrations and loads of 20 pesticides and degradation products, as well as copper were continuously recorded during the period of pesticide application (April to September 2009, 2010 and 2011) at the inlet, the outlet and in sediments of a stormwater wetland that collects runoff from a vineyard catchment. Removal rates of dissolved loads ranged from 39% (simazine) to 100% (cymoxanil, gluphosinate, kresoxim methyl and terbuthylazine). Dimethomorph, diuron, glyphosate and metalaxyl were more efficiently removed in spring than in summer. The calculation of sedimentation rates from discharge measurements and total suspended solids (TSS) values revealed that the wetland retained more than 77% of the input mass of suspended solids, underscoring the capability of the wetland to trap pesticide-laden particles. Only flufenoxuron was frequently detected in the wetland sediments. An inter-annual comparison showed that changes in the removal of aminomethylphosphonic acid (AMPA, a degradation product of glyphosate), isoxaben or simazine can be attributed mainly to the larger vegetation cover in 2010 compared to 2009. More than 80% of the copper load entering the wetland was retained in the sediments and the plants. Our results demonstrate that stormwater wetlands can efficiently remove pesticide mixtures and copper in agricultural runoff during critical periods of pesticide application. Nevertheless, fluctuations in the runoff regime, as well as the vegetation and hydrochemical characteristics affect the

  3. Treatment of suspended solids and heavy metals from urban stormwater runoff by a tree box filter.

    Science.gov (United States)

    Geronimo, F K F; Maniquiz-Redillas, M C; Tobio, J A S; Kim, L H

    2014-01-01

    Particulates, inorganic and toxic constituents are the most common pollutants associated with urban stormwater runoff. Heavy metals such as chromium, nickel, copper, zinc, cadmium and lead are found to be in high concentration on paved roads or parking lots due to vehicle emissions. In order to control the rapid increase of pollutant loads in stormwater runoff, the Korean Ministry of Environment proposed the utilization of low impact developments. One of these was the application of tree box filters that act as a bioretention treatment system which executes filtration and sorption processes. In this study, a tree box filter located adjacent to an impervious parking lot was developed to treat suspended solids and heavy metal concentrations from urban stormwater runoff. In total, 11 storm events were monitored from July 2010 to August 2012. The results showed that the tree box filter was highly effective in removing particulates (up to 95%) and heavy metals (at least 70%) from the urban stormwater runoff. Furthermore, the tree box filter was capable of reducing the volume runoff by 40% at a hydraulic loading rate of 1 m/day and below.

  4. Studies and Analysis of the Effectiveness of Stormwater Runoff Purification Equipment in Vilnius

    Directory of Open Access Journals (Sweden)

    Egidija Jaruševičiūtė

    2011-02-01

    Full Text Available In order to protect the natural environment from pollution, pollutant reduction in the stormwater runoff of urban areas is a particularly relevant factor. Uneven surface water flow and changes in pollutant concentration complicate conventional matching techniques and processes as well as prolong the duration of time which requires a comprehensive study in this area. Therefore, experiments on inflow stormwater turbidity and impurity with suspended solids and petroleum products were carried out according to the prepared sample collecting methodology. The study evaluated the effectiveness of cleaning a stormwater treatment plant along the settlement chamber in the chosen points. The settling time of impurities found in stormwater was analyzed under the presence of ideal conditions in the laboratory. The conducted experiments established dependence between suspended solids and turbidity. Stormwater pollution by SS was reduced only to 21–35% after heavy rain or a snow melting period in treatment plants. Keywords: storm water runoff, cleaning stormwater treatment plant, pollutants, turbidity, suspended solids, petrol products.DOI: 10.3846/mla.2010.087

  5. Sustainable oil and grease removal from synthetic stormwater runoff using bench-scale bioretention studies.

    Science.gov (United States)

    Hong, Eunyoung; Seagren, Eric A; Davis, Allen P

    2006-02-01

    One of the principal components of the contaminant load in urban stormwater runoff is oil and grease (O&G) pollution, resulting from vehicle emissions. A mulch layer was used as a contaminant trap to remove O&G (dissolved and particulate-associated naphthalene, dissolved toluene, and dissolved motor oil hydrocarbons) from a synthetic runoff during a bench-scale infiltration study. Approximately 80 to 95% removal of all contaminants from synthetic runoff was found via sorption and filtration. Subsequently, approximately 90% of the sorbed naphthalene, toluene, oil, and particulate-associated naphthalene was biodegraded within approximately 3, 4, 8, and 2 days after the event, respectively, based on decreases in contaminant concentrations coupled with increases of microbial populations. These results indicate the effectiveness and sustainability of placing a thin layer of mulch on the surface of a bioretention facility for reducing O&G pollution from urban stormwater runoff.

  6. Effect of urban stormwater runoff on ground water beneath recharge basins on Long Island, New York

    Science.gov (United States)

    Ku, H.F.; Simmons, D.L.

    1986-01-01

    Urban stormwater runoff was monitored during 1980-82 to investigate the source, type, quantity, and fate of contaminants routed to the more than 3,000 recharge basins on Long Island and to determine whether this runoff might be a significant source of contamination to the groundwater reservoir. Forty-six storms were monitored at five recharge basins in representative land use areas (strip commercial, shopping-mall parking lot, major highway, low-density residential, and medium-density residential). Runoff:precipitation ratios indicate that all storm runoff is derived from precipitation on impervious surfaces in the drainage area, except during storms of high intensity or long duration, when additional runoff can be derived from precipitation on permeable surfaces. Lead was present in highway runoff in concentrations up to 3300 micrograms/L, and chloride was found in parking lot runoff concentrations up to 1,100 mg/L during winter, when salt is used for deicing. In the five composite stormwater samples and nine groundwater grab samples that were analyzed for 113 EPA-designated ' priority pollutants, ' four constituents were detected in concentrations exceeding New York State guidelines of 50 micrograms/L for an individual organic compound in drinking water: p-chloro-m-cresol (79 micrograms/L); 2 ,4-dimethylphenol (96 micrograms/L); 4-nitrophenol (58 micrograms/L); and methylene chloride (230 micrograms/L in either groundwater or stormwater at the highway basin). One stormwater sample and two groundwater samples exceeded New York State guidelines for total organic compounds in drinking water (100 micrograms/L). The presence of these constituents is attributed to contamination from point sources rather than to the quality of runoff from urban areas. The median number of indicator bacteria in stormwater ranged from 0.1 to 10 billion MPN/100 ml. Fecal coliforms and fecal streptococci increased by 1 to 2 orders of magnitude during the warm season. The use of recharge

  7. Effect of climate change on stormwater runoff characteristics and treatment efficiencies of stormwater retention ponds; a case study from Denmark using TSS and Cu as indicator pollutants. SpringerPlus, 5:1984, 1-12

    DEFF Research Database (Denmark)

    Sharma, Anitha Kumari; Vezzaro, Luca; Birch, Heidi

    2016-01-01

    This study investigated the potential effect of climate changes on stormwater pollution runoff characteristics and the treatment efficiency of a stormwater retention pond in a 95 ha catchment in Denmark. An integrated dynamic stormwater runoff quality and treatment model was used to simulate two...... scenarios: one representing the current climate and another representing a future climate scenario with increased intensity of extreme rainfall events and longer dry weather periods. 100-year long high-resolution rainfall time series downscaled from regional climate model projections were used as input...... concentrations. The future climate simulations showed an increased frequency of higher flows and increased total concentrations discharged from the catchment. The effect on the outlet from the pond was an increase in the total concentrations (TSS and Cu), whereas no major effect was observed on dissolved Cu...

  8. Uncertainty in monitoring E. coli concentrations in streams and stormwater runoff

    Science.gov (United States)

    Harmel, R. D.; Hathaway, J. M.; Wagner, K. L.; Wolfe, J. E.; Karthikeyan, R.; Francesconi, W.; McCarthy, D. T.

    2016-03-01

    Microbial contamination of surface waters, a substantial public health concern throughout the world, is typically identified by fecal indicator bacteria such as Escherichia coli. Thus, monitoring E. coli concentrations is critical to evaluate current conditions, determine restoration effectiveness, and inform model development and calibration. An often overlooked component of these monitoring and modeling activities is understanding the inherent random and systematic uncertainty present in measured data. In this research, a review and subsequent analysis was performed to identify, document, and analyze measurement uncertainty of E. coli data collected in stream flow and stormwater runoff as individual discrete samples or throughout a single runoff event. Data on the uncertainty contributed by sample collection, sample preservation/storage, and laboratory analysis in measured E. coli concentrations were compiled and analyzed, and differences in sampling method and data quality scenarios were compared. The analysis showed that: (1) manual integrated sampling produced the lowest random and systematic uncertainty in individual samples, but automated sampling typically produced the lowest uncertainty when sampling throughout runoff events; (2) sample collection procedures often contributed the highest amount of uncertainty, although laboratory analysis introduced substantial random uncertainty and preservation/storage introduced substantial systematic uncertainty under some scenarios; and (3) the uncertainty in measured E. coli concentrations was greater than that of sediment and nutrients, but the difference was not as great as may be assumed. This comprehensive analysis of uncertainty in E. coli concentrations measured in streamflow and runoff should provide valuable insight for designing E. coli monitoring projects, reducing uncertainty in quality assurance efforts, regulatory and policy decision making, and fate and transport modeling.

  9. Bioaccumulation of heavy metals in fauna from wet detention ponds for stormwater runoff

    DEFF Research Database (Denmark)

    Stephansen, Diana; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild;

    2012-01-01

    Stormwater detention ponds remove pollutants e.g. heavy metals and nutrients from stormwater runoff. These pollutants accumulate in the pond sediment and thereby become available for bioaccumulation in fauna living in the ponds. In this study the bioaccumulation was investigated by fauna samples...... from 5 wet detention ponds for analyses of heavy metal contents. Five rural shallow lakes were included in the study to survey the natural occurrence of heavy metals in water-dwelling fauna. Heavy metal concentrations in water-dwelling fauna were generally found higher in wet detention ponds compared...

  10. EVALUATION OF RETENTION POND AND CONSTRUCTED WETLAND BMPS FOR TREATING PARTICULATE-BOUND HEAVY METALS IN URBAN STORMWATER RUNOFF - 2007

    Science.gov (United States)

    The sources of heavy metals in urban stormwater runoff are diverse (e.g., highways, road surfaces, roofs) and the release of metals into the environment is governed by several complex mechanisms. Heavy metals in stormwater are associated with suspended particulate materials that ...

  11. A flexible framework for process-based hydraulic and water quality modeling of stormwater green infrastructure performance

    Science.gov (United States)

    Background Models that allow for design considerations of green infrastructure (GI) practices to control stormwater runoff and associated contaminants have received considerable attention in recent years. While popular, generally, the GI models are relatively simplistic. However,...

  12. DEMONSTRATION AND EVALUATION OF PROCESSED FOREST BIOMASS IN BIORETENTION CELLS FOR REDUCTION OF WILDFIRE HAZARD AND TREATMENT OF STORMWATER RUNOFF

    OpenAIRE

    Templeton, Scott; Privette, Charles V., III; Hayes, John,; Post, Christopher; Sharma, Ritu

    2004-01-01

    Growth of urban areas and impervious surfaces in the U.S. has increased the environmental impacts of stormwater runoff and the public’s interest in regulation of those who discharge it. Growth of communities in the urban-wildland interface is an important reason why risks of wildfire have increased and government agencies have undertaken new collaborative efforts to reduce them. A bioretention cell is a space-saving method to manage stormwater runoff from streets and parking lots. Widespread ...

  13. Soil bioretention protects juvenile salmon and their prey from the toxic impacts of urban stormwater runoff.

    Science.gov (United States)

    McIntyre, J K; Davis, J W; Hinman, C; Macneale, K H; Anulacion, B F; Scholz, N L; Stark, J D

    2015-08-01

    Green stormwater infrastructure (GSI), or low impact development, encompasses a diverse and expanding portfolio of strategies to reduce the impacts of stormwater runoff on natural systems. Benchmarks for GSI success are usually framed in terms of hydrology and water chemistry, with reduced flow and loadings of toxic chemical contaminants as primary metrics. Despite the central goal of protecting aquatic species abundance and diversity, the effectiveness of GSI treatments in maintaining diverse assemblages of sensitive aquatic taxa has not been widely evaluated. In the present study we characterized the baseline toxicity of untreated urban runoff from a highway in Seattle, WA, across six storm events. For all storms, first flush runoff was toxic to the daphniid Ceriodaphnia dubia, causing up to 100% mortality or impairing reproduction among survivors. We then evaluated whether soil media used in bioretention, a conventional GSI method, could reduce or eliminate toxicity to juvenile coho salmon (Oncorhynchus kisutch) as well as their macroinvertebrate prey, including cultured C. dubia and wild-collected mayfly nymphs (Baetis spp.). Untreated highway runoff was generally lethal to salmon and invertebrates, and this acute mortality was eliminated when the runoff was filtered through soil media in bioretention columns. Soil treatment also protected against sublethal reproductive toxicity in C. dubia. Thus, a relatively inexpensive GSI technology can be highly effective at reversing the acutely lethal and sublethal effects of urban runoff on multiple aquatic species.

  14. Stormwater runoff quality in correlation to land use and land cover development in Yongin, South Korea.

    Science.gov (United States)

    Paule, M A; Memon, S A; Lee, B-Y; Umer, S R; Lee, C-H

    2014-01-01

    Stormwater runoff quality is sensitive to land use and land cover (LULC) change. It is difficult to understand their relationship in predicting the pollution potential and developing watershed management practices to eliminate or reduce the pollution risk. In this study, the relationship between LULC change and stormwater runoff quality in two separate monitoring sites comprising a construction area (Site 1) and mixed land use (Site 2) was analyzed using geographic information system (GIS), event mean concentration (EMC), and correlation analysis. It was detected that bare land area increased, while other land use areas such as agriculture, commercial, forest, grassland, parking lot, residential, and road reduced. Based on the analyses performed, high maximum range and average EMCs were found in Site 2 for most of the water pollutants. Also, urban areas and increased conversion of LULC into bare land corresponded to degradation of stormwater quality. Correlation analysis between LULC and stormwater quality showed the influence of different factors such as farming practices, geographical location, and amount of precipitation, vegetation loss, and anthropogenic activities in monitoring sites. This research found that GIS application was an efficient tool for monthly monitoring, validation and statistical analysis of LULC change in the study area.

  15. Characterization and source identification of stormwater runoff in tropical urban catchments.

    Science.gov (United States)

    Chow, M F; Yusop, Z

    2014-01-01

    The characteristics of urban stormwater pollution in the tropics are still poorly understood. This issue is crucial to the tropical environment because its rainfall and runoff generation processes are so different from temperate regions. In this regard, a stormwater monitoring program was carried out at three urban catchments (e.g. residential, commercial and industrial) in the southern part of Peninsular Malaysia. A total of 51 storm events were collected at these three catchments. Samples were analyzed for total suspended solids, 5-day biochemical oxygen demand, chemical oxygen demand (COD), oil and grease, nitrate nitrogen, nitrite nitrogen, ammonia nitrogen (NH3-N), soluble reactive phosphorus and total phosphorus. Principal component analysis (PCA) and hierarchical cluster analysis were used to interpret the stormwater quality data for pattern recognition and identification of possible sources. The most likely sources of stormwater pollutants at the residential catchment were from surface soil and leachate of fertilizer from domestic lawns and gardens, whereas the most likely sources for the commercial catchment were from discharges of food waste and washing detergent. In the industrial catchment, the major sources of pollutants were discharges from workshops and factories. The PCA factors further revealed that COD and NH3-N were the major pollutants influencing the runoff quality in all three catchments.

  16. Micropollutants in stormwater runoff and combined sewer overflow in the Copenhagen area, Denmark.

    Science.gov (United States)

    Birch, H; Mikkelsen, P S; Jensen, J K; Lützhøft, H-C Holten

    2011-01-01

    Stormwater runoff contains a broad range of micropollutants. In Europe a number of these substances are regulated through the Water Framework Directive, which establishes Environmental Quality Standards (EQSs) for surface waters. Knowledge about discharge of these substances through stormwater runoff and combined sewer overflows (CSOs) is essential to ensure compliance with the EQSs. Results from a screening campaign including more than 50 substances at four stormwater discharge locations and one CSO in Copenhagen are reported here. Heavy metal concentrations were detected at levels similar to earlier findings, e.g., with copper found at concentrations up to 13 times greater than the Danish standard for surface waters. The concentration of polyaromatic hydrocarbons (PAHs) exceeded the EQSs by factors up to 500 times for stormwater and 2,000 times for the CSO. Glyphosate was found in all samples whilst diuron, isoproturon, terbutylazine and MCPA were found only in some of the samples. Diethylhexylphthalate (DEHP) was also found at all five locations in concentrations exceeding the EQS. The results give a valuable background for designing further monitoring programmes focusing on the chemical status of surface waters in urban areas.

  17. Evaluating stormwater micropollutant control strategies by the application of an integrated model

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Sharma, Anitha Kumari; Ledin, Anna

    2011-01-01

    The estimation of micropollutant (MP) fluxes in stormwater systems is a fundamental task to enable the elaboration of strategies to reduce stormwater MP discharge to natural waters. Dynamic models can represent important tools which can integrate the limited data provided by monitoring campaigns....... This study presents an application of an integrated dynamic model to estimate MP fluxes in stormwater systems in combination with stormwater quality measurements. MP sources were identified by using GIS land usage data. Runoff quality was simulated by using a conceptual accumulation/washoff model......-control strategy in terms of MP loads discharged in the environment and sediment accumulated in the pond, highlighting the potential of integrated models as support for stormwater pollution management....

  18. Comparison of the treatment performance of hybrid constructed wetlands treating stormwater runoff.

    Science.gov (United States)

    Choi, J Y; Maniquiz-Redillas, M C; Hong, J S; Lee, S Y; Kim, L H

    2015-01-01

    This study was conducted to compare the treatment performance of two hybrid constructed wetlands (CWs) in treating stormwater runoff. The hybrid CWs were composed of a combination of free water surface (FWS) and horizontal subsurface flow (HSSF) CWs. Based on the results, strong correlation exists between potential runoff impacts and stormwater characteristics; however, the low correlations also suggest that not only the monitored parameters contribute to stormwater event mean concentrations (EMC) of pollutants, but other factors should also be considered as well. In the hydraulic and treatment performance of the hybrid CWs, a small surface area to catchment area (SA/CA) ratio, receiving a high concentration of influent EMC, will find it hard to achieve great removal efficiency; also a large SA/CA ratio, receiving low concentration of influent EMC, will find it hard to achieve great removal efficiency. With this, SA/CA ratio and influent characteristics such as EMC or load should be considered among the design factors of CWs. The performance data of the two CWs were used to consider the most cost-effective design of a hybrid CW. The optimum facility capacity (ratio of total runoff volume to storage volume) that is applicable for a target volume reduction and removal efficiency was provided in this study.

  19. Water-quality characteristics of stormwater runoff in Rapid City, South Dakota, 2008-14

    Science.gov (United States)

    Hoogestraat, Galen K.

    2015-01-01

    The water quality of Rapid Creek is important because the reach that flows through Rapid City, South Dakota, is a valuable spawning area for a self-sustaining trout fishery, actively used for recreation, and a seasonal municipal water supply for the City of Rapid City. This report presents the current (2008–14) water-quality characteristics of urban stormwater runoff in selected drainage networks within the City of Rapid City, and provides an evaluation of the pollutant reductions of wetland channels implemented as a best-management practice. Stormwater runoff data were collected at nine sites in three drainage basins within Rapid City: the Arrowhead (2 monitoring sites), Meade-Hawthorne (1 monitoring site), and Downtown (6 monitoring sites) drainage basins. Stormwater runoff was evaluated for concentrations of total suspended solids (TSS) and bacteria at sites in the Arrowhead and Meade-Hawthorne drainage basins, and for concentrations of TSS, chloride, bacteria, nutrients, and metals at sites in the Downtown drainage basin.

  20. a Study of Urban Stormwater Modeling Approach in Singapore Catchment

    Science.gov (United States)

    Liew, S. C.; Liong, S. Y.; Vu, M. T.

    2011-07-01

    Urbanization has the direct effect of increasing the amount of surface runoff to be discharged through man-made drainage systems. Thus, Singapore's rapid urbanization has drawn great attention on flooding issues. In view of this, proper stormwater modeling approach is necessary for the assessment planning, design, and control of the storm and combines sewerage system. Impacts of urbanization on surface runoff and catchment flooding in Singapore are studied in this paper. In this study, the application of SOBEK-urban 1D is introduced on model catchments and a hypothetical catchment model is created for simulation purpose. Stormwater modeling approach using SOBEK-urban offers a comprehensive modeling tool for simple or extensive urban drainage systems consisting of sewers and open channels despite its size and complexity of the network. The findings from the present study show that stormwater modeling is able to identify flood area and the impact of the anticipated sea level on urban drainage network. Consequently, the performance of the urban drainage system can be improved and early prevention approaches can be carried out.

  1. Removal of dissolved heavy metals from pre-settled stormwater runoff by iron-oxide coated sand (IOCS)

    DEFF Research Database (Denmark)

    Møller, J.; Ledin, Anna; Mikkelsen, Peter Steen

    2002-01-01

    Sorption to iron-oxide coated sand (IOCS) is a promosing technology for removal of the dissolved heavy metal fraction in stormwater runoff. The development of a new technology is necessary since studies of stormwater runoff from traffic areas indicate that an oil separator and detention pond may...... not guarantee that emission limit values set by the Danish EPA are satisfied. Runoff water was sampled from an urban highway, allowed to settle for 24 hours to simulate the effect of a detention pond, and finally spiked with metals to ensure concentration levels similar to high levels reported in the leterature...

  2. Stormwater Management: Calculation of Traffic Area Runoff Loads and Traffic Related Emissions

    Directory of Open Access Journals (Sweden)

    Maximilian Huber

    2016-07-01

    Full Text Available Metals such as antimony, cadmium, chromium, copper, lead, nickel, and zinc can be highly relevant pollutants in stormwater runoff from traffic areas because of their occurrence, toxicity, and non-degradability. Long-term measurements of their concentrations, the corresponding water volumes, the catchment areas, and the traffic volumes can be used to calculate specific emission loads and annual runoff loads that are necessary for mass balances. In the literature, the annual runoff loads are often specified by a distinct catchment area (e.g., g/ha. These loads were summarized and discussed in this paper for all seven metals and three types of traffic areas (highways, parking lots, and roads; 45 sites. For example, the calculated median annual runoff loads of all sites are 355 g/ha for copper, 110 g/ha for lead (only data of the 21st century, and 1960 g/ha for zinc. In addition, historical trends, annual variations, and site-specific factors were evaluated for the runoff loads. For Germany, mass balances of traffic related emissions and annual heavy metal runoff loads from highways and total traffic areas were calculated. The influences on the mass fluxes of the heavy metal emissions and the runoff pollution were discussed. However, a statistical analysis of the annual traffic related metal fluxes, in particular for different traffic area categories and land uses, is currently not possible because of a lack of monitoring data.

  3. Understanding the factors influencing the removal of heavy metals in urban stormwater runoff.

    Science.gov (United States)

    Maniquiz-Redillas, Marla C; Kim, Lee-Hyung

    2016-01-01

    In this research, an infiltration trench equipped with an extensive pretreatment and filter bed consisting of woodchip, sand and gravel was utilized as a low impact development technique to manage stormwater runoff from a highly impervious road with particular emphasis on heavy metal removal. Findings revealed that the major factors influencing the removal of heavy metals were the concentration of the particulate matters and heavy metals in runoff, runoff volume and flow rates. The reduction of heavy metals was enhanced by sedimentation of particulates through pretreatment. Fine particles (design considerations. Sediment was most highly attached on the surface area of woodchip than to other filter media like sand, gravel and geotextile. It is suggested that maintenance must be performed after the end of the winter season wherein high sediment rate was observed to maintain the efficiency of the treatment system.

  4. Trace Metals in Urban Stormwater Runoff and their Management

    Science.gov (United States)

    Li, T.; Hall, K.; Li, L. Y.; Schreier, H.

    2009-04-01

    In past decades, due to the rapid urbanization, land development has replaced forests, fields and meadows with impervious surfaces such as roofs, parking lots and roads, significantly affecting watershed quality and having an impact on aquatic systems. In this study, non-point source pollution from a diesel bus loop was assessed for the extent of trace metal contamination of Cu, Mn, Fe, and Zn in the storm water runoff. The study was carried out at the University of British Columbia (UBC) in the Greater Vancouver Regional District (GVRD) of British Columbia, Canada. Fifteen storm events were monitored at 3 sites from the diesel bus loop to determine spatial and temporal variations of dissolved and total metal concentrations in the storm water runoff. The dissolved metal concentrations were compared with the provincial government discharge criteria and the bus loop storm water quality was also compared with previous studies conducted across the GVRD urban area. To prevent storm water with hazardous levels of contaminants from being discharged into the urban drainage system, a storm water catch basin filter was installed and evaluated for its efficiency of contaminants removal. The perlite filter media adsorption capacities for the trace metals, oil and grease were studied for better maintenance of the catch basin filter. Dissolved copper exceeded the discharge criteria limit in 2 out of 15 cases, whereas dissolved zinc exceeded the criteria in 4 out of 15 cases, and dissolved manganese was below the criteria in all of the events sampled. Dissolved Cu and Zn accounted for 36 and 45% of the total concentration, whereas Mn and Fe only accounted for 20 and 4% of their total concentration, respectively. Since they are more mobile and have higher bioaccumulation potentials, Zn and Cu are considered to be more hazardous to the aquatic environment than Fe and Mn. With high imperviousness (100%) and intensive traffic at the UBC diesel bus loop, trace metal concentrations

  5. Monitoring and predicting the fecal indicator bacteria concentrations from agricultural, mixed land use and urban stormwater runoff.

    Science.gov (United States)

    Paule-Mercado, M A; Ventura, J S; Memon, S A; Jahng, D; Kang, J-H; Lee, C-H

    2016-04-15

    While the urban runoff are increasingly being studied as a source of fecal indicator bacteria (FIB), less is known about the occurrence of FIB in watershed with mixed land use and ongoing land use and land cover (LULC) change. In this study, Escherichia coli (EC) and fecal streptococcus (FS) were monitored from 2012 to 2013 in agricultural, mixed and urban LULC and analyzed according to the most probable number (MPN). Pearson correlation was used to determine the relationship between FIB and environmental parameters (physicochemical and hydrometeorological). Multiple linear regressions (MLR) were used to identify the significant parameters that affect the FIB concentrations and to predict the response of FIB in LULC change. Overall, the FIB concentrations were higher in urban LULC (EC=3.33-7.39; FS=3.30-7.36log10MPN/100mL) possibly because of runoff from commercial market and 100% impervious cover (IC). Also, during early-summer season; this reflects a greater persistence and growth rate of FIB in a warmer environment. During intra-event, however, the FIB concentrations varied according to site condition. Anthropogenic activities and IC influenced the correlation between the FIB concentrations and environmental parameters. Stormwater temperature (TEMP), turbidity, and TSS positively correlated with the FIB concentrations (p>0.01), since IC increased, implying an accumulation of bacterial sources in urban activities. TEMP, BOD5, turbidity, TSS, and antecedent dry days (ADD) were the most significant explanatory variables for FIB as determined in MLR, possibly because they promoted the FIB growth and survival. The model confirmed the FIB concentrations: EC (R(2)=0.71-0.85; NSE=0.72-0.86) and FS (R(2)=0.65-0.83; NSE=0.66-0.84) are predicted to increase due to urbanization. Therefore, these findings will help in stormwater monitoring strategies, designing the best management practice for FIB removal and as input data for stormwater models.

  6. Comparison of Contaminant Transport in Agricultural Drainage Water and Urban Stormwater Runoff.

    Science.gov (United States)

    Ghane, Ehsan; Ranaivoson, Andry Z; Feyereisen, Gary W; Rosen, Carl J; Moncrief, John F

    2016-01-01

    Transport of nitrogen and phosphorus from agricultural and urban landscapes to surface water bodies can cause adverse environmental impacts. The main objective of this long-term study was to quantify and compare contaminant transport in agricultural drainage water and urban stormwater runoff. We measured flow rate and contaminant concentration in stormwater runoff from Willmar, Minnesota, USA, and in drainage water from subsurface-drained fields with surface inlets, namely, Unfertilized and Fertilized Fields. Commercial fertilizer and turkey litter manure were applied to the Fertilized Field based on agronomic requirements. Results showed that the City Stormwater transported significantly higher loads per unit area of ammonium, total suspended solids (TSS), and total phosphorus (TP) than the Fertilized Field, but nitrate load was significantly lower. Nitrate load transport in drainage water from the Unfertilized Field was 58% of that from the Fertilized Field. Linear regression analysis indicated that a 1% increase in flow depth resulted in a 1.05% increase of TSS load from the City Stormwater, a 1.07% increase in nitrate load from the Fertilized Field, and a 1.11% increase in TP load from the Fertilized Field. This indicates an increase in concentration with a rise in flow depth, revealing that concentration variation was a significant factor influencing the dynamics of load transport. Further regression analysis showed the importance of targeting high flows to reduce contaminant transport. In conclusion, for watersheds similar to this one, management practices should be directed to load reduction of ammonium and TSS from urban areas, and nitrate from cropland while TP should be a target for both.

  7. Sublethal toxicity of orchard stormwater runoff in Sacramento splittail (Pogonichthys macrolepidotus) larvae.

    Science.gov (United States)

    Teh, Swee J; Deng, DongFang; Werner, Inge; Teh, FooChing; Hung, Silas S O

    2005-04-01

    The sublethal effects of stormwater runoff from sections of a plum orchard treated with esfenvalerate or diazinon were evaluated in 7-day-old Sacramento splittail (Pogonichthys macrolepidotus) larvae. Fish were exposed to eight runoff samples using the USEPA standard static renewal method for 96 h acute toxicity testing, then transferred to clean water for three-month to assess the survival, growth, histopathological abnormalities, and heat stress proteins (hsp). No significant mortality was observed at 96 h in exposed fish. At one week, histopathological abnormalities included severe glycogen depletion, cytoplasmic protein droplets, vacuolar degeneration, and cell necroses in liver of all exposure groups. Pyknotic nerve cells were seen in brain of one exposure group. Significantly higher cumulative mortality, lower condition factor, and elevated hsp60 and hsp70 levels (p < 0.05) were occurred in several exposure groups. No histopathological abnormalities were observed after three months in any exposure group. This study confirms that standard acute toxicity tests have underestimated the toxicity of stormwater runoff, and although splittail larvae survived the 96 h exposure, they exhibited reduced survival and growth and showed signs of cellular stress even after a three month recovery period.

  8. Enhanced Stormwater Contaminant Removal and Improved Runoff Quality Using Modified Sorbents in Tree Filters

    Science.gov (United States)

    Schifman, L. A.; Kasaraneni, V.; Boving, T. B.; Oyanedel-Craver, V.

    2013-12-01

    Stormwater runoff, particularly in urban areas, contains high concentrations of pathogens that are often cited as one of the main reasons for beach closings and other water quality issues in coastal areas. Commonly found contaminants in runoff are often addressed by structural best management practices (BMP) that capture and treat the runoff before discharging it. Many BMP, such as tree filters, act as primary filtration devices that attenuate total suspended solids, nutrients, and heavy metals from runoff, but typically these BMPs are not designed to treat bacteria and have only minor petroleum hydrocarbon (PH) treatment capabilities. To address this shortcoming, the contaminant retention of an alternative sorption material was compared to expanded shale that is usually used in tree filters. Red cedar wood chips were modified with either Quaternary Ammonium Silane (QAS) or Silver Nanoparticles (AgNPs) to provide antimicrobial properties to the matrix and/or exploit their affinity to sorb PH, particularly polycyclic aromatic hydrocarbons (PAH). Results show that the wood chips exhibit the highest sorption capacity for QAS, making this material favorable for treating bacteria, while at the same time attenuating PAH by sorption processes. In the case of AgNP amendment to wood, less AgNP uptake and more desorption from the wood matrix was observed, making this amendment less favorable for bacteria deactivation. Batch experiments show that wood chips modified with QAS can remove up to 3 orders of magnitude of bacteria and retain up to 0.1 mg/g of PAH compared to shale, which has very limited bacteria deactivation (less than one order of magnitude) a PAH retention capacity of 0.04 mg/g. In this talk, the contaminant removal efficiency of the modified and unmodified materials will be discussed on the background of how these materials may find use in enhanced treatment of stormwater in tree filter BMPs.

  9. Stormwater run-off and pollutant transport related to the activities carried out in a modern waste management park.

    Science.gov (United States)

    Marques, M; Hogland, W

    2001-02-01

    Stormwater run-off from twelve different areas and roads has been characterized in a modern waste disposal site, where several waste management activities are carried out. Using nonparametric statistics, medians and confidence intervals of the medians, 22 stormwater quality parameters were calculated. Suspended solids, chemical oxygen demand, biochemical oxygen demand, total nitrogen and total phosphorus, as well as run-off from several areas, showed measured values above standard limits for discharge into recipient waters--even higher than those of leachate from covered landfill cells. Of the heavy metals analyzed, copper, zinc and nickel were the most prevalent, being detected in every sample. Higher concentrations of metals such as zinc, nickel, cobalt, iron and cadmium were found in run-off from composting areas, compared to areas containing stored and exposed scrap metal. This suggests that factors other than the total amount of exposed material affect the concentration of metals in run-off, such as binding to organic compounds and hydrological transport efficiency. The pollutants transported by stormwater represent a significant environmental threat, comparable to leachate. Careful design, monitoring and maintenance of stormwater run-off drainage systems and infiltration elements are needed if infiltration is to be used as an on-site treatment strategy.

  10. Green infrastructure retrofits on residential parcels: Ecohydrologic modeling for stormwater design

    Science.gov (United States)

    Miles, B.; Band, L. E.

    2014-12-01

    To meet water quality goals stormwater utilities and not-for-profit watershed organizations in the U.S. are working with citizens to design and implement green infrastructure on residential land. Green infrastructure, as an alternative and complement to traditional (grey) stormwater infrastructure, has the potential to contribute to multiple ecosystem benefits including stormwater volume reduction, carbon sequestration, urban heat island mitigation, and to provide amenities to residents. However, in small (1-10-km2) medium-density urban watersheds with heterogeneous land cover it is unclear whether stormwater retrofits on residential parcels significantly contributes to reduce stormwater volume at the watershed scale. In this paper, we seek to improve understanding of how small-scale redistribution of water at the parcel scale as part of green infrastructure implementation affects urban water budgets and stormwater volume across spatial scales. As study sites we use two medium-density headwater watersheds in Baltimore, MD and Durham, NC. We develop ecohydrology modeling experiments to evaluate the effectiveness of redirecting residential rooftop runoff to un-altered pervious surfaces and to engineered rain gardens to reduce stormwater runoff. As baselines for these experiments, we performed field surveys of residential rooftop hydrologic connectivity to adjacent impervious surfaces, and found low rates of connectivity. Through simulations of pervasive adoption of downspout disconnection to un-altered pervious areas or to rain garden stormwater control measures (SCM) in these catchments, we find that most parcel-scale changes in stormwater fate are attenuated at larger spatial scales and that neither SCM alone is likely to provide significant changes in streamflow at the watershed scale.

  11. Impact of Urbanization on Stormwater Runoff from a Small Urban Catchment: Gdańsk Małomiejska Basin Case Study

    Science.gov (United States)

    Olechnowicz, Borys; Weinerowska-Bords, Katarzyna

    2014-12-01

    This paper deals with the impact of different forms of urbanization on the basin outflow. The influence of changes in land cover/use, drainage system development, reservoirs, and alternative ways of stormwater management (green roofs, permeable pavements) on basin runoff was presented in the case of a small urban basin in Gdansk (Poland). Seven variants of area development (in the period of 2000-2012) - three historical and four hypothetical - were analyzed. In each case, runoff calculations for three rainfall scenarios were carried out by means of the Hydrologic Modeling System designed by Hydrologic Engineering Center of the U.S. Army Corps of Engineers (HEC-HMS). The Soil Conservation Service (SCS) Curve Number (CN) method was used for calculations of effective rainfall, the kinematic wave model for those of overland flow, and the Muskingum-Cunge model for those of channel routing. The calculations indicated that urban development had resulted in increased peak discharge and runoff volume and in decreased peak time. On the other hand, a significant reduction in peak values was observed for a relatively small decrease in the normal storage level (NSL) in reservoirs or when green roofs on commercial centers were present. The study confirmed a significant increase in runoff as a result of urbanization and a considerable runoff reduction by simple alternative ways of stormwater management.

  12. Statistical Approaches to Interpretation of Local, Regional, and National Highway-Runoff and Urban-Stormwater Data

    Science.gov (United States)

    Tasker, Gary D.; Granato, Gregory E.

    2000-01-01

    Decision makers need viable methods for the interpretation of local, regional, and national-highway runoff and urban-stormwater data including flows, concentrations and loads of chemical constituents and sediment, potential effects on receiving waters, and the potential effectiveness of various best management practices (BMPs). Valid (useful for intended purposes), current, and technically defensible stormwater-runoff models are needed to interpret data collected in field studies, to support existing highway and urban-runoffplanning processes, to meet National Pollutant Discharge Elimination System (NPDES) requirements, and to provide methods for computation of Total Maximum Daily Loads (TMDLs) systematically and economically. Historically, conceptual, simulation, empirical, and statistical models of varying levels of detail, complexity, and uncertainty have been used to meet various data-quality objectives in the decision-making processes necessary for the planning, design, construction, and maintenance of highways and for other land-use applications. Water-quality simulation models attempt a detailed representation of the physical processes and mechanisms at a given site. Empirical and statistical regional water-quality assessment models provide a more general picture of water quality or changes in water quality over a region. All these modeling techniques share one common aspect-their predictive ability is poor without suitable site-specific data for calibration. To properly apply the correct model, one must understand the classification of variables, the unique characteristics of water-resources data, and the concept of population structure and analysis. Classifying variables being used to analyze data may determine which statistical methods are appropriate for data analysis. An understanding of the characteristics of water-resources data is necessary to evaluate the applicability of different statistical methods, to interpret the results of these techniques

  13. Intra-event variability of Escherichia coli and total suspended solids in urban stormwater runoff.

    Science.gov (United States)

    McCarthy, D T; Hathaway, J M; Hunt, W F; Deletic, A

    2012-12-15

    Sediment levels are important for environmental health risk assessments of surface water bodies, while faecal pollution can introduce significant public health risks for users of these systems. Urban stormwater is one of the largest sources of contaminants to surface waters, yet the fate and transport of these contaminants (especially those microbiological) have received little attention in the literature. Stormwater runoff from five urbanized catchments were monitored for pathogen indicator bacteria and total suspended solids in two developed countries. Multiple discrete samples were collected during each storm event, allowing an analysis of intra-event characteristics such as initial concentration, peak concentration, maximum rate of change, and relative confidence interval. The data suggest that a catchment's area influences pollutant characteristics, as larger catchments have more complex stormwater infrastructure and more variable pollutant sources. The variability of total suspended solids for many characteristics was similar to Escherichia coli, indicating that the variability of E. coli may not be substantially higher than that of other pollutants as initially speculated. Further, variations in E. coli appeared to be more commonly correlated to antecedent climate, while total suspended solids were more highly correlated to rainfall/runoff characteristics. This emphasizes the importance of climate on microbial persistence and die off in urban systems. Discrete intra-event concentrations of total suspended solids and, to a lesser extent E. coli, were correlated to flow, velocity, and rainfall intensity (adjusted by time of concentrations). Concentration changes were found to be best described by adjusted rainfall intensity, as shown by other researchers. This study has resulted in an increased understanding of the magnitude of intra-event variations of total suspended solids and E. coli and what physical and climatic parameters influence these variations

  14. Modeling the hydrologic and economic efficacy of stormwater utility credit programs for US single family residences.

    Science.gov (United States)

    Kertesz, Ruben; Green, Olivia Odom; Shuster, William D

    2014-01-01

    As regulatory pressure to reduce the environmental impact of urban stormwater intensifies, US municipalities increasingly seek a dedicated source of funding for stormwater programs, such as a stormwater utility. In rare instances, single family residences are eligible for utility discounts for installing green infrastructure. This study examined the hydrologic and economic efficacy of four such programs at the parcel scale: Cleveland (OH), Portland (OR), Fort Myers (FL), and Lynchburg (VA). Simulations were performed to model the reduction in stormwater runoff by implementing bioretention on a typical residential property according to extant administrative rules. The EPA National Stormwater Calculator was used to perform pre- vs post-retrofit comparisons and to demonstrate its ease of use for possible use by other cities in utility planning. Although surface slope, soil type and infiltration rate, impervious area, and bioretention parameters were different across cities, our results suggest that modeled runoff volume was most sensitive to percent of total impervious area that drained to the bioretention cell, with soil type the next most important factor. Findings also indicate a persistent gap between the percentage of annual runoff reduced and the percentage of fee reduced.

  15. Pollutants in stormwater runoff in Shanghai (China): Implications for management of urban runoff pollution

    Institute of Scientific and Technical Information of China (English)

    Siaka Ballo; Min Liu; Lijun Hou; Jing Chang

    2009-01-01

    Runoff samples were collected from four functional areas (traffic, residential, commercial and industrial) and four roof types (old con-crete, new concrete, old clay and new clay) in central Shanghai, China, during rain events. The event mean concentrations (EMCs) of three forms of nitrogen (NH4+-N,NO3--N,NO2--N) and the temporal variations of total phosphorus (TP) were then measured to evaluate the effects of runoff from different areas on water quality management. The results revealed that the TP levels varied significantly in the samples collected from different functional areas and roof types during rain events. In addition, although the NO3--N and NO2--N concentrations in runoff remained well below the fifth class values of the national surface water quality standards, the NH4+-N levels were 1.36, 1.17, 1.10 and 0.85 times higher than the standard value in samples collected from commercial, traffic, indus-trial, and residential areas, respectively. Similarly, the concentrations of NH4+-N in samples collected from old concrete, new concrete, old clay and new clay roofs exceeded the fifth class standard by 6.66, 5.72, 4.32 and 3.32 times, respectively. And the NO3--N levels were 1.86 and 1.53 times higher than the standard values in runoff samples collected from new and old concrete roofs, respectively.

  16. Stormwater runoff pollutant loading distributions and their correlation with rainfall and catchment characteristics in a rapidly industrialized city.

    Science.gov (United States)

    Li, Dongya; Wan, Jinquan; Ma, Yongwen; Wang, Yan; Huang, Mingzhi; Chen, Yangmei

    2015-01-01

    Fast urbanization and industrialization in developing countries result in significant stormwater runoff pollution, due to drastic changes in land-use, from rural to urban. A three-year study on the stormwater runoff pollutant loading distributions of industrial, parking lot and mixed commercial and residential catchments was conducted in the Tongsha reservoir watershed of Dongguan city, a typical, rapidly industrialized urban area in China. This study presents the changes in concentration during rainfall events, event mean concentrations (EMCs) and event pollution loads per unit area (EPLs). The first flush criterion, namely the mass first flush ratio (MFFn), was used to identify the first flush effects. The impacts of rainfall and catchment characterization on EMCs and pollutant loads percentage transported by the first 40% of runoff volume (FF40) were evaluated. The results indicated that the pollutant wash-off process of runoff during the rainfall events has significant temporal and spatial variations. The mean rainfall intensity (I), the impervious rate (IMR) and max 5-min intensity (Imax5) are the critical parameters of EMCs, while Imax5, antecedent dry days (ADD) and rainfall depth (RD) are the critical parameters of FF40. Intercepting the first 40% of runoff volume can remove 55% of TSS load, 53% of COD load, 58% of TN load, and 61% of TP load, respectively, according to all the storm events. These results may be helpful in mitigating stormwater runoff pollution for many other urban areas in developing countries.

  17. Stormwater Runoff Pollutant Loading Distributions and Their Correlation with Rainfall and Catchment Characteristics in a Rapidly Industrialized City

    Science.gov (United States)

    Li, Dongya; Wan, Jinquan; Ma, Yongwen; Wang, Yan; Huang, Mingzhi; Chen, Yangmei

    2015-01-01

    Fast urbanization and industrialization in developing countries result in significant stormwater runoff pollution, due to drastic changes in land-use, from rural to urban. A three-year study on the stormwater runoff pollutant loading distributions of industrial, parking lot and mixed commercial and residential catchments was conducted in the Tongsha reservoir watershed of Dongguan city, a typical, rapidly industrialized urban area in China. This study presents the changes in concentration during rainfall events, event mean concentrations (EMCs) and event pollution loads per unit area (EPLs). The first flush criterion, namely the mass first flush ratio (MFFn), was used to identify the first flush effects. The impacts of rainfall and catchment characterization on EMCs and pollutant loads percentage transported by the first 40% of runoff volume (FF40) were evaluated. The results indicated that the pollutant wash-off process of runoff during the rainfall events has significant temporal and spatial variations. The mean rainfall intensity (I), the impervious rate (IMR) and max 5-min intensity (Imax5) are the critical parameters of EMCs, while Imax5, antecedent dry days (ADD) and rainfall depth (RD) are the critical parameters of FF40. Intercepting the first 40% of runoff volume can remove 55% of TSS load, 53% of COD load, 58% of TN load, and 61% of TP load, respectively, according to all the storm events. These results may be helpful in mitigating stormwater runoff pollution for many other urban areas in developing countries. PMID:25774922

  18. Determining Spatial Distribution And Air-Water Exchange Of Polycyclic Aromatic Hydrocarbons In Stormwater Runoff Catchment Basins

    Science.gov (United States)

    Kasaraneni, V. K.; Schifman, L. A.; Craver, V.; Boving, T. B.

    2014-12-01

    Stormwater runoff is a conduit for several pollutants such as polycyclic aromatic hydrocarbons (PAHs) in to surface and ground water bodies. The control of runoff and pollutants is typically addressed by best management practices (BMPs), such as retention/detention ponds or catchment basins in general. The effectiveness of catchment basins in reducing the volume of runoff and removal of some contaminants has been established. However, very little is known about the fate of the contaminants settled within these structures. In coastal regions and places with shallow groundwater tables accumulation of high concentrations of PAHs in the bottom sediments poses a potential threat for groundwater contamination. The concentrations of PAHs accumulated in the sediments of these catchment basins will primarily depend on the sources of runoff origin and the surrounding land use. Due to the physico-chemical characteristics of PAHs, their transport not only can occur in the liquid and solid phase, but it is also possible that gaseous emissions can be produced from BMP systems. For the purpose of this study, five stormwater catchment basins along the I-95 corridor in Rhode Island were selected based on the stormwater runoff origin and covering (industrial, urban, highway, and commercial) land uses. To study the stratification of PAHs sediment cores one foot were collected and analyzed for 31PAHs (16 EPA parent PAH and 15 methylated PAHs). In order to determine whether the catchment basins are a source of atmospheric pollution polyethylene passive samplers were deployed to determine the freely dissolved PAHs in the water column and gas phase PAHs at the air-water interface. This presentation will describe how PAH fluxes move between three environmental compartments (sediments, water column, atmosphere) within the five stormwater catchment basins. Further, it will be investigated whether these BMP structures can act as contaminant sources rather than sinks and whether BMP

  19. Evaluation of accuracy of linear regression models in predicting urban stormwater discharge characteristics.

    Science.gov (United States)

    Madarang, Krish J; Kang, Joo-Hyon

    2014-06-01

    Stormwater runoff has been identified as a source of pollution for the environment, especially for receiving waters. In order to quantify and manage the impacts of stormwater runoff on the environment, predictive models and mathematical models have been developed. Predictive tools such as regression models have been widely used to predict stormwater discharge characteristics. Storm event characteristics, such as antecedent dry days (ADD), have been related to response variables, such as pollutant loads and concentrations. However it has been a controversial issue among many studies to consider ADD as an important variable in predicting stormwater discharge characteristics. In this study, we examined the accuracy of general linear regression models in predicting discharge characteristics of roadway runoff. A total of 17 storm events were monitored in two highway segments, located in Gwangju, Korea. Data from the monitoring were used to calibrate United States Environmental Protection Agency's Storm Water Management Model (SWMM). The calibrated SWMM was simulated for 55 storm events, and the results of total suspended solid (TSS) discharge loads and event mean concentrations (EMC) were extracted. From these data, linear regression models were developed. R(2) and p-values of the regression of ADD for both TSS loads and EMCs were investigated. Results showed that pollutant loads were better predicted than pollutant EMC in the multiple regression models. Regression may not provide the true effect of site-specific characteristics, due to uncertainty in the data.

  20. Sources and mechanisms of nitrate and orthophosphate transport in urban stormwater runoff from residential catchments.

    Science.gov (United States)

    Yang, Yun-Ya; Toor, Gurpal S

    2017-04-01

    Nutrients export from residential catchments contributes to water quality impairment in urban water bodies. We investigated the concentrations, transport mechanisms, and sources of nitrate-nitrogen (NO3-N) and orthophosphate-phosphorus (PO4-P) in urban stormwater runoff generated in residential catchments in Tampa Bay, Florida, United States. Street runoff samples, collected over 21 storm events, were supplemented with rainfall and roof runoff samples from six representative residential catchments. Samples were analyzed for N and P forms, N and oxygen (O) isotopes of nitrate (δ(18)O-NO3(-) and δ(15)N-NO3(-)), and δ(18)O and hydrogen (δD) isotopes of water (H2O). We found that the main NO3-N source in street runoff was atmospheric deposition (range: 35-64%), followed by chemical N fertilizers (range: 1-39%), and soil and organic N (range: 7-33%), whereas PO4-P in the street runoff likely originated from erosion of soil particles and mineralization from organic materials (leaves, grass clippings). The variability in the sources and concentrations of NO3-N and PO4-P across catchments is attributed to different development designs and patterns, use of various fill materials during land development, and landscaping practices. This data can be useful to develop strategies to offset the impacts of urban development (e.g., designs and patterns resulting in variable impervious areas) and management (e.g., fertilizer use, landscaping practices) on NO3-N and PO4-P transport in urban residential catchments.

  1. Road traffic impact on urban water quality: a step towards integrated traffic, air and stormwater modelling.

    Science.gov (United States)

    Fallah Shorshani, Masoud; Bonhomme, Céline; Petrucci, Guido; André, Michel; Seigneur, Christian

    2014-04-01

    Methods for simulating air pollution due to road traffic and the associated effects on stormwater runoff quality in an urban environment are examined with particular emphasis on the integration of the various simulation models into a consistent modelling chain. To that end, the models for traffic, pollutant emissions, atmospheric dispersion and deposition, and stormwater contamination are reviewed. The present study focuses on the implementation of a modelling chain for an actual urban case study, which is the contamination of water runoff by cadmium (Cd), lead (Pb), and zinc (Zn) in the Grigny urban catchment near Paris, France. First, traffic emissions are calculated with traffic inputs using the COPERT4 methodology. Next, the atmospheric dispersion of pollutants is simulated with the Polyphemus line source model and pollutant deposition fluxes in different subcatchment areas are calculated. Finally, the SWMM water quantity and quality model is used to estimate the concentrations of pollutants in stormwater runoff. The simulation results are compared to mass flow rates and concentrations of Cd, Pb and Zn measured at the catchment outlet. The contribution of local traffic to stormwater contamination is estimated to be significant for Pb and, to a lesser extent, for Zn and Cd; however, Pb is most likely overestimated due to outdated emissions factors. The results demonstrate the importance of treating distributed traffic emissions from major roadways explicitly since the impact of these sources on concentrations in the catchment outlet is underestimated when those traffic emissions are spatially averaged over the catchment area.

  2. Nano- and microparticles and associated pollutants in stormwater runoff: effects of disc filtration with and without flocculant addition

    DEFF Research Database (Denmark)

    Nielsen, Katrine; Mørch-Madsen, Andreas; Mikkelsen, Peter Steen;

    2014-01-01

    the sizes of particles found in stormwater from roads and to evaluate the use of a cationic organic flocculant to increase the size of the particles and thereby increase the removal efficiency of a 10 μm disc filter. The samples were collected in connection with a project testing a pilot scale disc filter...... for treating stormwater runoff. The micro-sized particles were found to be mainly 2.1-19 μm in diameter and nano-sized particles were also observed (86-228 nm). Although the flocculant increased the observed volume of the micro-sized particles by 46%, the majority of the particles where still

  3. Regional Analysis of Stormwater Runoff for the Placement of Managed Aquifer Recharge Sites in Santa Cruz and Northern Monterey Counties, California

    Science.gov (United States)

    Young, K. S.; Beganskas, S.; Fisher, A. T.

    2015-12-01

    We apply a USGS surface hydrology model, Precipitation-Runoff Modeling System (PRMS), to analyze stormwater runoff in Santa Cruz and Northern Monterey Counties, CA with the goal of supplying managed aquifer recharge (MAR) sites. Under the combined threats of multiyear drought and excess drawdown, this region's aquifers face numerous sustainability challenges, including seawater intrusion, chronic overdraft, increased contamination, and subsidence. This study addresses the supply side of this resource issue by increasing our knowledge of the spatial and temporal dynamics of runoff that could provide water for MAR. Ensuring the effectiveness of MAR using stormwater requires a thorough understanding of runoff distribution and site-specific surface and subsurface aquifer conditions. In this study we use a geographic information system (GIS) and a 3-m digital elevation model (DEM) to divide the region's four primary watersheds into Hydrologic Response Units (HRUs), or topographic sub-basins, that serve as discretized input cells for PRMS. We then assign vegetation, soil, land use, slope, aspect, and other characteristics to these HRUs, from a variety of data sources, and analyze runoff spatially using PRMS under varying precipitation conditions. We are exploring methods of linking spatially continuous and high-temporal-resolution precipitation datasets to generate input precipitation catalogs, facilitating analyses of a variety of regimes. To gain an understanding of how surface hydrology has responded to land development, we will also modify our input data to represent pre-development conditions. Coupled with a concurrent MAR suitability analysis, our model results will help screen for locations of future MAR projects and will improve our understanding of how changes in land use and climate impact hydrologic runoff and aquifer recharge.

  4. Evaluation of undersized bioretention stormwater control measures for treatment of highway bridge deck runoff.

    Science.gov (United States)

    Luell, S K; Hunt, W F; Winston, R J

    2011-01-01

    Two grassed bioretention cells were constructed in the easement of a bridge deck in Knightdale, North Carolina, USA, in October, 2009. One was intentionally undersized ('small'), while the other was full sized ('large') per current North Carolina standards. The large and small cells captured runoff from the 25- and 8-mm events, respectively. Both bioretention cells employed average fill media depths of 0.65 m and internal water storage (IWS) zones of 0.6 m. Flow-proportional, composite water quality samples were collected and analyzed for nitrogen species, phosphorus species, and TSS. During 13 months of data collection, the large cell's median effluent concentrations and loads were less than those from the small cell. The small cell's TN and TSS load reductions were 84 and 50%, respectively, of those achieved by the large cell, with both cells significantly reducing TN and TSS. TP loads were not significantly reduced by either cell, likely due to low TP concentrations in the highway runoff which may have approached irreducible levels. Outflow pollutant loads from the large and small cell were not significantly different from one another for any of the examined pollutants. The small cell's relative performance provides support for retrofitting undersized systems in urbanized areas where there is insufficient space available for conventional full-sized stormwater treatment systems.

  5. Urban Stormwater Characterization, Control, and Treatment.

    Science.gov (United States)

    Vogel, Jason R; Moore, Trisha L

    2016-10-01

    The following review presents a synthesis of 181 journal articles published during 2015 that represent progress toward better characterizing, controlling, and treating urban stormwater runoff. The review is structured by general topical areas related to (1) stormwater quality and quantity characterization; (2) engineered stormwater control and treatment practices, including erosion and sediment control, stormwater ponds, constructed stormwater wetlands, bioretention, permeable pavement, greenroofs, and rainwater harvesting systems; and (3) watershed-scale modeling and optimization of stormwater control and treatment practices. Common research themes emerging from this collection of studies include potential to enhance hydrologic and pollutant treatment performance of stormwater practices via media amendments and the use of innovative outlet control structures, as well as development of a more mechanistic understanding of hydrologic and water-quality functions to inform modeling and performance predictions. These studies serve to expand the field's knowledge base and will inform future efforts to further improve stormwater control and treatment at various spatial and temporal scales.

  6. Limited Influence of Urban Stormwater Runoff on Salt Marsh Platform and Marsh Creek Oxygen Dynamics in Coastal Georgia.

    Science.gov (United States)

    Savidge, William B; Brink, Jonathan; Blanton, Jackson O

    2016-12-01

    Oxygen concentrations and oxygen utilization rates were monitored continuously for 23 months on marsh platforms and in small tidal creeks at two sites in coastal Georgia, USA, that receive urban stormwater runoff via an extensive network of drainage canals. These data were compared to nearby control sites that receive no significant surface runoff. Overall, rainfall and runoff per se were not associated with differences in the oxygen dynamics among the different locations. Because of the large tidal range and long tidal excursions in coastal Georgia, localized inputs of stormwater runoff are rapidly mixed with large volumes of ambient water. Oxygen concentrations in tidal creeks and on flooded marsh platforms were driven primarily by balances of respiration and photosynthesis in the surrounding regional network of marshes and open estuarine waters. Local respiration, while measurable, was of relatively minor importance in determining oxygen concentrations in tidal floodwaters. Water residence time on the marshes could explain differences in oxygen concentration between the runoff-influenced and control sites.

  7. Limited Influence of Urban Stormwater Runoff on Salt Marsh Platform and Marsh Creek Oxygen Dynamics in Coastal Georgia

    Science.gov (United States)

    Savidge, William B.; Brink, Jonathan; Blanton, Jackson O.

    2016-12-01

    Oxygen concentrations and oxygen utilization rates were monitored continuously for 23 months on marsh platforms and in small tidal creeks at two sites in coastal Georgia, USA, that receive urban stormwater runoff via an extensive network of drainage canals. These data were compared to nearby control sites that receive no significant surface runoff. Overall, rainfall and runoff per se were not associated with differences in the oxygen dynamics among the different locations. Because of the large tidal range and long tidal excursions in coastal Georgia, localized inputs of stormwater runoff are rapidly mixed with large volumes of ambient water. Oxygen concentrations in tidal creeks and on flooded marsh platforms were driven primarily by balances of respiration and photosynthesis in the surrounding regional network of marshes and open estuarine waters. Local respiration, while measurable, was of relatively minor importance in determining oxygen concentrations in tidal floodwaters. Water residence time on the marshes could explain differences in oxygen concentration between the runoff-influenced and control sites.

  8. Stormwater runoff mitigation and nutrient leaching from a green roof designed to attract native pollinating insects

    Science.gov (United States)

    Fogarty, S.; Grogan, D. S.; Hale, S. R.

    2013-12-01

    A green roof is typically installed for one of two reasons: to mitigate the 'urban heat island' effect, reducing ambient temperatures and creating energy savings, or to reduce both the quantity and intensity of stormwater runoff, which is a major cause of river erosion and eutrophication. The study of green roofs in the United States has focused on commercial systems that use a proprietary expanded shale or clay substrate, along with succulent desert plants (mainly Sedum species). The green roof has the potential not only to provide thermal insulation and reduce storm runoff, but also to reclaim some of the natural habitat that has been lost to the built environment. Of special importance is the loss of habitat for pollinating insects, particularly native bees, which have been in decline for at least two decades. These pollinators are essential for crop production and for the reproduction of at least 65% of wild plants globally. Our study involves the installation of a small (4ft by 4ft), self-designed green roof system built with readily available components from a hardware store. The garden will be filled with a soilless potting mix, combined with 15% compost, and planted with grasses and wildflowers native to the Seacoast, New Hampshire region. Some of the plant species are used by bees for nesting materials, while others provide food in the form of nectar, pollen, and seeds for bees, butterflies, hummingbirds, and granivorous birds. We monitor precipitation on the roof and runoff from the garden on a per storm basis, and test grab samples of runoff for dissolved organic nitrogen and phosphorous. Runoff and nutrient concentration results are compared to a non-vegetated roof surface, and a proprietary Green Grid green roof system. This project is designed to address three main questions of interest: 1) Can these native plant species, which potentially provide greater ecosystem services than Sedum spp. in the form of food and habitat, survive in the conditions on

  9. Pollutant concentrations and pollution loads in stormwater runoff from different land uses in Chongqing

    Institute of Scientific and Technical Information of China (English)

    Shumin Wang; Qiang He; Hainan Ai; Zhentao Wang; Qianqian Zhang

    2013-01-01

    To investigate the distribution of pollutant concentrations and pollution loads in stormwater runoff in Chongqing,six typical land use types were selected and studied from August 2009 to September 2011.Statistical analysis on the distribution of pollutant concentrations in all water samples shows that pollutant concentrations fluctuate greatly in rainfall-runoff,and the concentrations of the same pollutant also vary greatly in different rainfall events.In addition,it indicates that the event mean concentrations (EMCs) of total suspended solids (TSS) and chemical oxygen demand (COD) from urban traffic roads (UTR) are significantly higher than those from residential roads (RR),commercial areas (CA),concrete roofs (CR),tile roofs (TRoof,and campus catchment areas (CCA); and the EMCs of total phosphorus (TP) and NH3-N from UTR and CA are 2.35-5 and 3 times of the class-Ⅲ standard values specified in the Environmental Quality Standards for Surface Water (GB 3838-2002).The EMCs of Fe,Pb and Cd are also much higher than the class-Ⅲ standard values.The analysis of pollution load producing coefficients (PLPC) reveals that the main pollution source of TSS,COD and TP is UTR.The analysis of correlations between rainfall factors and EMCs/PLPC indicates that rainfall duration is correlated with EMCs/PLPC of TSS for TRoof and TP for UTR,while rainfall intensity is correlated with EMCs/PLPC of TP for both CR and CCA.The results of this study provide a reference for better management of non-point source pollution in urban regions.

  10. Evaluating Urbanization Impacts from Non-Point Stormwater Runoff using Geospatial Analysis

    Science.gov (United States)

    Zivkovich, B. R.; Mays, D. C.

    2015-12-01

    Sediments, nutrients and other chemical impairments caused by urbanization continue to deteriorate natural ecosystem processes, resulting in the current degraded state of urban surface waters. Understanding non-point source impacts on these natural ecosystems has become a prevalent topic in sustainable urban infrastructure design as efforts to restore the urban hydrologic regime continue to drive engineers, planners, and environmentalists to develop optimal design practices for rapidly expanding built environments. To best understand how and where these impairments are received, the U.S. Environmental Protection Agency and other organizations have adopted urban runoff programs to identify contributions from non-point sources. This presentation provides a geospatial analysis method for identifying non-point source watersheds, and associated sub-basins, that contribute the highest loads of pollutants to receiving urban streams and lakes. This method, using a form of linear matrix inversion, is an area-averaged weighting method for non-point pollutants that corresponds to a geospatial land cover analysis. This two-phase analysis can be used to aid all parties in understanding how different land use types affect urban stream systems and processes. Optimal locations for water quality features (i.e., best management practices) can be evaluated in order to reduce, capture, and treat stormwater runoff as close to the source as possible. These best management practices have the ability to operate most effectively when located properly, because their ability to act as a minor treatment and prevention system is of great important for the restoration of the urban hydrologic regime.

  11. Pollutant concentrations and pollution loads in stormwater runoff from different land uses in Chongqing.

    Science.gov (United States)

    Wang, Shumin; He, Qiang; Ai, Hainan; Wang, Zhentao; Zhang, Qianqian

    2013-03-01

    To investigate the distribution of pollutant concentrations and pollution loads in stormwater runoff in Chongqing, six typical land use types were selected and studied from August 2009 to September 2011. Statistical analysis on the distribution of pollutant concentrations in all water samples shows that pollutant concentrations fluctuate greatly in rainfall-runoff, and the concentrations of the same pollutant also vary greatly in different rainfall events. In addition, it indicates that the event mean concentrations (EMCs) of total suspended solids (TSS) and chemical oxygen demand (COD) from urban traffic roads (UTR) are significantly higher than those from residential roads (RR), commercial areas (CA), concrete roofs (CR), tile roofs (TRoof), and campus catchment areas (CCA); and the EMCs of total phosphorus (TP) and NH3-N from UTR and CA are 2.35-5 and 3 times of the class-II standard values specified in the Environmental Quality Standards for Surface Water (GB 3838-2002). The EMCs of Fe, Pb and Cd are also much higher than the class-III standard values. The analysis of pollution load producing coefficients (PLPC) reveals that the main pollution source of TSS, COD and TP is UTR. The analysis of correlations between rainfall factors and EMCs/PLPC indicates that rainfall duration is correlated with EMCs/PLPC of TSS for TRoof and TP for UTR, while rainfall intensity is correlated with EMCs/PLPC of TP for both CR and CCA. The results of this study provide a reference for better management of non-point source pollution in urban regions.

  12. Use of SPMDs to determine average water concentration of polycyclic aromatic hydrocarbons in urban stormwater runoff

    Energy Technology Data Exchange (ETDEWEB)

    DeVita, W.; Crunkilton, R. [Univ. of Wisconsin, Stevens Point, WI (United States)

    1995-12-31

    Semipermeable polymeric membrane devices (SPMDS) were deployed for 30 day periods to monitor polycyclic aromatic hydrocarbons (PAHs) in an urban stream which receives much of its flow from urban runoff. SPMDs are capable of effectively sampling several liters of water per day for some PAHs. Unlike conventional methods, SPMDs sample only those non-polar organic contaminants which are truly dissolved and available for bioconcentration. Also, SPMDs may concentrate contaminants from episodic events such as stormwater discharge. The State of Wisconsin has established surface water quality criteria based upon human lifetime cancer risk of 23 ppt for benzo(a)pyrene and 23 ppt as the sum of nine other potentially carcinogenic PAHs. Bulk water samples analyzed by conventional methodology were routinely well above this criteria, but contained particulate bound PAHs as well as PAHs bound by dissolved organic carbon (DOC) which are not available for bioconcentration. Average water concentrations of dissolved PAHs determined using SPMDs were also above this criteria. Variables used for determining water concentration included sampling rate at the exposure temperature, length of exposure and estimation of biofouling of SPMD surface.

  13. Stormwater infiltration and surface runoff pollution reduction performance of permeable pavement layers.

    Science.gov (United States)

    Niu, Zhi-Guang; Lv, Zhi-Wei; Zhang, Ying; Cui, Zhen-Zhen

    2016-02-01

    In this paper, the laboratory-scale permeable pavement layers, including a surface permeable brick layer, coarse sand bedding layers (thicknesses = 2, 3.5, and 5 cm), and single-graded gravel sub-base layers (thicknesses = 15, 20, 25, and 30 cm), were built to evaluate stormwater infiltration and surface runoff pollution reduction performance. And, the infiltration rate (I) and concentrations of suspended solids (SS), total phosphorus (TP), chemical oxygen demand (COD), ammonia nitrogen, and total nitrogen (TN) were measured under the simulated rainfall intensity of 72.4 mm/h over duration of 60 min. The results indicate that the thickness factor primarily influences the infiltration rate and pollutant removal rate. The highest steady infiltration rate was for surface brick layer 51.0 mm/h, for 5-cm sand bedding layer 32.3 mm/h, and for 30-cm gravel sub-base layer 42.3 mm/h, respectively. The SS average removal rate was relative higher (79.8 ∼ 98.6 %) for all layers due to the interception and filtration. The average removal rates of TP and COD were for surface layer 71.2 and 24.1 %, for 5-cm bedding layer 54.8 and 9.0 %, and for 20-cm sub-base layer 72.2 and 26.1 %. Ammonia nitrogen and TN cannot steadily be removed by layers according to the experiment results. The optimal thickness of bedding sands was 5 cm, and that of sub-base gravels was 20 ∼ 30 cm.

  14. Treatment of Stormwater Runoff and Landfill Leachates Using a Surface Flow Constructed Wetland

    Directory of Open Access Journals (Sweden)

    A. Snow

    2008-01-01

    Full Text Available A surface flow wetland was constructed in the Burnside Industrial Park, Dartmouth, Nova Scotia, to treat stormwater runoff from the surrounding watersheds which are comprised primarily of commercial properties and two former landfills. The aim was to protect a freshwater ecosystem that consists of a 4.6 km long brook and two lakes. The ability of the constructed wetland to retain iron and manganese from the influent water was investigated and the change in pH of the water as it flowed through the cells was assessed. In 2004, the total iron removal efficiency of the constructed wetland ranged from a low of 47.13 % to a high of 84.74 % and in 2006 ranged from a low of 35.56 % to a high of 78.49 % depending on rain events. The outlet total iron concentrations in 2006 were not significantly different from those reported for 2004. In 2004, the total manganese removal efficiency of the constructed wetland ranged from a low of 25.75 % to a high of 51.61 % and in 2006 ranged from a low of 0.0 % to a high of 33.33 % depending on rain events. The inlet and the outlet total manganese concentrations in the constructed wetland from August to October 2006 were significantly higher than the inlet and the outlet total manganese concentrations reported for August to October 2004 because water levels in the constructed wetland were very low and the average pH of the outlet water was lower in 2006. In 2004 and 2006, the pH of the water in the constructed wetland had average inlet values of 6.70 and 6.26 and average outlet values of 7.28 and 6.70, respectively.

  15. Comparison of filter media materials for heavy metal removal from urban stormwater runoff using biofiltration systems.

    Science.gov (United States)

    Lim, H S; Lim, W; Hu, J Y; Ziegler, A; Ong, S L

    2015-01-01

    The filter media in biofiltration systems play an important role in removing potentially harmful pollutants from urban stormwater runoff. This study compares the heavy metal removal potential (Cu, Zn, Cd, Pb) of five materials (potting soil, compost, coconut coir, sludge and a commercial mix) using laboratory columns. Total/dissolved organic carbon (TOC/DOC) was also analysed because some of the test materials had high carbon content which affects heavy metal uptake/release. Potting soil and the commercial mix offered the best metal uptake when dosed with low (Cu: 44.78 μg/L, Zn: 436.4 μg/L, Cd, 1.82 μg/L, Pb: 51.32 μg/L) and high concentrations of heavy metals (Cu: 241 μg/L, Zn: 1127 μg/L, Cd: 4.57 μg/L, Pb: 90.25 μg/L). Compost and sludge also had high removal efficiencies (>90%). Heavy metal leaching from these materials was negligible. A one-month dry period between dosing experiments did not affect metal removal efficiencies. TOC concentrations from all materials increased after the dry period. Heavy metal removal was not affected by filter media depth (600 mm vs. 300 mm). Heavy metals tended to accumulate at the upper 5 cm of the filter media although potting soil showed bottom-enriched concentrations. We recommend using potting soil as the principal media mixed with compost or sludge since these materials perform well and are readily available. The use of renewable materials commonly found in Singapore supports a sustainable approach to urban water management.

  16. Stormwater run-off from an industrial log yard: characterization, contaminant correlation and first-flush phenomenon.

    Science.gov (United States)

    Kaczala, Fabio; Marques, Marcia; Vinrot, Eva; Hogland, William

    2012-01-01

    The stormwater run-off generated in an industrial log yard during eight run-off events was studied with the main focus on the transport of toxic metals. Associations between water quality constituents and potential surrogates were evaluated by correlation analysis. The first-flush phenomenon was verified by normalized M(V) curves. The results have shown that, whereas some metals such as Zn, Ba, Cd, As and Fe were always detected in these waters, others (Cr, Pb, Cu, Ni, V, Co) were not. Large variations in the water constituents' concentrations were observed, with Fe, Pb and V being the most variable ones. Concentrations of Zn and Cu in the run-off waters exceeded the values established by the Swedish environmental authorities in 100% and 97% of samples, respectively. The correlation analyses indicated TSS as a potential surrogate of Pb, V, Co, Ni, As, Ba, Cr and COD (0.949 > R > 0.808), making it reasonable to state that a treatment system with focus on TSS removal would also reduce toxic metals from these waters. The first-flush phenomenon was evident for most of the constituents. Significant differences (p yard were mainly composed ofZn, Cu and Ba. Knowledge of the physicochemical characteristics, discharge dynamics and the storm variables involved in the process is a crucial step for the proposal and implementation of a stormwater management programme.

  17. Sorption of PAHs to humic acid- and iron(III)carbon ate particles by using passive dosing vials for investigating the transport of organic contamination in stormwater runoff

    DEFF Research Database (Denmark)

    Nielsen, Katrine; Mikkelsen, Peter Steen; Baun, Anders

    2013-01-01

    During the last decades, the growing urbanisation a nd increasing anthropogenic activities in urban areas have turned urban stormwater runoff int o a surface water quality contamination problem. The concerns of urban stormwater runoff as a source of contamination in the receiving surface water...... (lakes, rivers or sea) have been raised by researchers throughout the world (e.g. Broman et. al., 1987, and Xanthopoulos et. al., 1990), and have in Europe gained increased interest in relation to the implementatio n of the Water Framework Directive (WFD, 2000/60/EC). Particles (often defined as >0.45 μm......) has been foun d to facilitate transport of organic contaminants and metals in stormwater runoff system s, but little is known about the role of the colloidal fraction including nano-sized particl es (0.001-1 μm). Based on the large specific surface area of colloids and nanosized particles, t heir...

  18. Investigating the appropriate level of complexity for stormwater micropollutants modelling

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen

    2011-01-01

    The increasing importance of stormwater micropollutants (MP) management boosted the use of mathematical models in this field. Several approaches with different level of spatial and temporal resolution have been applied in the last years. This study compared modelling approaches differing for thei......The increasing importance of stormwater micropollutants (MP) management boosted the use of mathematical models in this field. Several approaches with different level of spatial and temporal resolution have been applied in the last years. This study compared modelling approaches differing...

  19. Green Infrastructure Design for Stormwater Runoff and Water Quality: Empirical Evidence from Large Watershed-Scale Community Developments

    Directory of Open Access Journals (Sweden)

    Bo Yang

    2013-12-01

    Full Text Available Green infrastructure (GI design is advocated as a new paradigm for stormwater management, whereas current knowledge of GI design is mostly based on isolated design strategies used at small-scale sites. This study presents empirical findings from two watershed-scale community projects (89.4 km2 and 55.7 km2 in suburban Houston, Texas. The GI development integrates a suite of on-site, infiltration-based stormwater management designs, and an adjacent community development follows conventional drainage design. Parcel data were used to estimate the site impervious cover area. Observed streamflow and water quality data (i.e., NO3-N, NH3-N, and TP were correlated with the site imperviousness. Results show that, as of 2009, the impervious cover percentage in the GI site (32.3% is more than twice that of the conventional site (13.7%. However, the GI site’s precipitation-streamflow ratio maintains a steady, low range, whereas this ratio fluctuates substantially in the conventional site, suggesting a “flashy” stream condition. Furthermore, in the conventional site, annual nutrient loadings are significantly correlated with its impervious cover percentage (p < 0.01, whereas in the GI site there is little correlation. The study concludes that integrated GI design can be effective in stormwater runoff reduction and water quality enhancement at watershed-scale community development.

  20. Remaining Sites Verification Package for the 100-F-50 Stormwater Runoff Culvert, Waste Site Reclassification Form 2007-001

    Energy Technology Data Exchange (ETDEWEB)

    J. M. Capron

    2008-04-15

    The 100-F-50 waste site, part of the 100-FR-2 Operable Unit, is a steel stormwater runoff culvert that runs between two railroad grades in the south-central portion of the 100-F Area. The culvert exiting the west side of the railroad grade is mostly encased in concrete and surrounded by a concrete stormwater collection depression partially filled with soil and vegetation. The drain pipe exiting the east side of the railroad grade embankment is partially filled with soil and rocks. The 100-F-50 stormwater diversion culvert confirmatory sampling results support a reclassification of this site to no action. The current site conditions achieve the remedial action objectives and corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

  1. Remaining Sites Verification Package for the 100-F-50 Stormwater Runoff Culvert, Waste Site Reclassification Form 2007-001

    Energy Technology Data Exchange (ETDEWEB)

    J. M. Capron

    2008-04-15

    The 100-F-50 waste site, part of the 100-FR-2 Operable Unit, is a steel stormwater runoff culvert that runs between two railroad grades in the south-central portion of the 100-F Area. The culvert exiting the west side of the railroad grade is mostly encased in concrete and surrounded by a concrete stormwater collection depression partially filled with soil and vegetation. The drain pipe exiting the east side of the railroad grade embankment is partially filled with soil and rocks. The 100-F-50 stormwater diversion culvert confirmatory sampling results support a reclassification of this site to no action. The current site conditions achieve the remedial action objectives and corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

  2. Comparison of sediment and nutrient export and runoff characteristics from watersheds with centralized versus distributed stormwater management.

    Science.gov (United States)

    Hopkins, Kristina G; Loperfido, J V; Craig, Laura S; Noe, Gregory B; Hogan, Dianna M

    2017-12-01

    Stormwater control measures (SCMs) are used to retain stormwater and pollutants. SCMs have traditionally been installed in a centralized manner using detention to mitigate peak flows. Recently, distributed SCM networks that treat runoff near the source have been increasingly utilized. The aim of this study was to evaluate differences among watersheds that vary in SCM arrangement by assessing differences in baseflow nutrient (NOx-N and PO4(-)) concentrations and fluxes, stormflow export of suspended sediments and particulate phosphorus (PP), and runoff characteristics. A paired watershed approach was used to compare export between 2004 and 2016 from one forested watershed (For-MD), one suburban watershed with centralized SCMs (Cent-MD), and one suburban watershed with distributed SCMs (Dist-MD). Results indicated baseflow nitrate (NOx-N) concentrations typically exceeded 1 mg-N/L in all watersheds and were highest in Dist-MD. Over the last 10 years in Dist-MD, nitrate concentrations in both stream baseflow and in a groundwater well declined as land use shifted from agriculture to suburban. Baseflow nitrate export temporarily increased during the construction phase of SCM development in Dist-MD. This temporary pulse of nitrate may be attributed to the conversion of sediment control facilities to SCMs and increased subsurface flushing as infiltration SCMs came on line. During storm flow, Dist-MD tended to have less runoff and lower maximum specific discharge than Cent-MD for small events (1.3 cm). Mass export estimated during paired storm events indicated Dist-MD exported 30% less sediment and 31% more PP than Cent-MD. For large precipitation events, export of sediment and PP was similar among all three watersheds. Results suggest that distributed SCMs can reduce runoff and sediment loads during small rain events compared to centralized SCMs, but these differences become less evident for large events when peak discharge likely leads to substantial bank erosion

  3. Characterization of stormwater runoff from the Naval Air Station and Naval Wepons Industrial Reserve Plant, Dallas, Texas, 1994-96

    Science.gov (United States)

    Raines, T.H.; Baldys, Stanley; Lizarraga, J.S.

    1997-01-01

    The characterization of stormwater runoff from the Naval Air Station (NAS) and the Naval Weapons Industrial Reserve Plant (NWIRP), Dallas, Texas, is necessary to determine if runoff from the facilities is contributing to off-site contamination of surface waters, A network of five fixed sites and four grab sites was established to collect stormwater-runoff samples from a substantial part of the drainage area of each facility. Fixed sites were instrumented to measure and store precipitation, stage, discharge, and runoff-volume data and to collect flow-weighted composite samples during a storm. Grab and composite samples were collected for six storms at each of the five fixed sites from October 1994 to March 1996. The grab samples were analyzed for about 100 properties and constituents including specific conductance, pH, water temperature, bacteria, trace elements, oil and grease, total phenols, and volatile organic compounds. The composite samples were analyzed for about 220 properties and constituents including specific conductance, pH, chemical oxygen demand, biochemical oxygen demand, major ions, suspended and dissolved solids, nutrients, trace elements, total organic carbon, volatile organic compounds, semivolatile organic compounds, and organochlorine and organophosphorus pesticides. Grab samples were collected for two storms (September 18,1995, and October 2,1995) at each of the four grab sites. The grab samples were analyzed for about 80 constituents including specific conductance, pH, water temperature, trace elements, and volatile organic compounds. Composite samples were collected for two of the six storms sampled at the fixed sites and analyzed for aquatic toxicity. Fathead minnow growth and survival toxicity tests and water flea reproduction and survival toxicity tests were done.

  4. Comparison of sediment and nutrient export and runoff characteristics from watersheds with centralized versus distributed stormwater management

    Science.gov (United States)

    Hopkins, Kristina; Loperfido, J.V.; Craig, Laura S.; Noe, Gregory; Hogan, Dianna

    2017-01-01

    Stormwater control measures (SCMs) are used to retain stormwater and pollutants. SCMs have traditionally been installed in a centralized manner using detention to mitigate peak flows. Recently, distributed SCM networks that treat runoff near the source have been increasingly utilized. The aim of this study was to evaluate differences among watersheds that vary in SCM arrangement by assessing differences in baseflow nutrient (NOx-N and PO4−) concentrations and fluxes, stormflow export of suspended sediments and particulate phosphorus (PP), and runoff characteristics. A paired watershed approach was used to compare export between 2004 and 2016 from one forested watershed (For-MD), one suburban watershed with centralized SCMs (Cent-MD), and one suburban watershed with distributed SCMs (Dist-MD). Results indicated baseflow nitrate (NOx-N) concentrations typically exceeded 1 mg-N/L in all watersheds and were highest in Dist-MD. Over the last 10 years in Dist-MD, nitrate concentrations in both stream baseflow and in a groundwater well declined as land use shifted from agriculture to suburban. Baseflow nitrate export temporarily increased during the construction phase of SCM development in Dist-MD. This temporary pulse of nitrate may be attributed to the conversion of sediment control facilities to SCMs and increased subsurface flushing as infiltration SCMs came on line. During storm flow, Dist-MD tended to have less runoff and lower maximum specific discharge than Cent-MD for small events (1.3 cm). Mass export estimated during paired storm events indicated Dist-MD exported 30% less sediment and 31% more PP than Cent-MD. For large precipitation events, export of sediment and PP was similar among all three watersheds. Results suggest that distributed SCMs can reduce runoff and sediment loads during small rain events compared to centralized SCMs, but these differences become less evident for large events when peak discharge likely leads to substantial bank erosion.

  5. Adsorption characteristics of construction waste for heavy metals from urban stormwater runoff☆

    Institute of Scientific and Technical Information of China (English)

    Jianlong Wang; Pingping Zhang; Liqiong Yang; Tao Huang

    2015-01-01

    Stormwater runoff has become an important source of surface water pollution. Bioretention, a low impact devel-opment measure in urban stormwater management, has been proven to be effective in the removal of pol utants from stormwater runoff, with appropriate bioretention media. In this study, construction wastes were selected as bioretention media to remove heavy metals from stormwater runoff. Static and dynamic adsorption batch exper-iments were carried out to investigate the adsorption of heavy metals in simulated stormwater runoff system with construction wastes in different particle sizes. The experimental results show that the pseudo-second-order kinetic model characterizes the adsorption process and the adsorption equilibrium data are wel described by Freundlich isotherm model. The construction wastes used can remove heavy metals from stormwater runoff effectively, with their average removal rates al more than 90%. The particle size of construction wastes greatly influences the equilibrium time, rate and adsorption capacity for heavy metals.

  6. Copper mobilization affected by weather conditions in a stormwater detention system receiving runoff waters from vineyard soils (Champagne, France)

    Energy Technology Data Exchange (ETDEWEB)

    Banas, D., E-mail: damien.banas@u-psud.f [Univ. Reims Champagne-Ardenne, Lab. Eco-Toxicologie, BP 1039, F-51687 Reims Cedex 2 (France); Univ. Nancy, UR-AFPA, INRA, 2 Av. Foret Haye, F-54505 Vandoeuvre-les-Nancy (France); Marin, B., E-mail: beatrice.marin@univ-reims.f [Univ. Reims Champagne-Ardenne, EA3795 GEGENA, 2 Esplanade Roland Garros, F-51100 Reims (France); Skraber, S., E-mail: skraber@lippmann.l [Centre de Recherche Public, Gabriel Lippmann, Department of Environment and Agro-biotechnologies (EVA), 41 rue du Brill, L-4422 Belvaux (Luxembourg); Chopin, E.I.B., E-mail: chopin@oakland.ed [Oakland University, Department of Chemistry, Rochester, MI 48309 (United States); Zanella, A., E-mail: augusto.zanella@unipd.i [Univ. Padova, Facolta di Agraria, Viale dell' Universita 16, I-35020 Legnaro (Italy)

    2010-02-15

    Copper, a priority substance on the EU-Water Framework Directive list, is widely used to protect grapevines against fungus diseases. Many vineyards being located on steep slopes, large amounts of Cu could be discharged in downstream systems by runoff water. The efficiency of stormwater detention basins to retain copper in a vineyard catchment was estimated. Suspended solids, dissolved (Cu{sub diss}) and total Cu (Cu{sub tot}) concentrations were monitored in runoff water, upstream, into and downstream from a detention pond. Mean Cu{sub tot} concentrations in entering water was 53.6 mug/L whereas it never exceeded 2.4 mug/L in seepage. Cu{sub tot} concentrations in basin water (>100 mug/L in 24% of the samples) exceeded LC{sub 50} values for several aquatic animals. Copper was principally sequestered by reduced compounds in the basin sediments (2/3 of Cu{sub tot}). Metal sequestration was reversible since sediment resuspension resulted in Cu remobilization. Wind velocity controlled resuspension, explained 70% of Cu{sub diss} variability and could help predicting Cu mobilization. - Copper in stormwater basin is efficiently retained but can be released during windy events or after dredging.

  7. Cadmium removal from urban stormwater runoff via bioretention technology and effluent risk assessment for discharge to surface water

    Science.gov (United States)

    Wang, Jianlong; Zhang, Pingping; Yang, Liqiong; Huang, Tao

    2016-02-01

    Bioretention technology, a low-impact development stormwater management measure, was evaluated for its ability to remove heavy metals (specifically cadmium, Cd) from urban stormwater runoff. Fine sand, zeolite, sand and quartz sand were selected as composite bioretention media. The effects of these materials on the removal efficiency, chemical forms, and accumulation and migration characteristics of Cd were examined in laboratory scale bioretention columns. Heretofore, few studies have examined the removal of Cd by bioretention. A five-step sequential extraction method, a single-contamination index method, and an empirical migration equation were used in the experiments. The average Cd removal efficiency of quartz sand approached 99%, and removal by the other media all exceeded 90%. The media types markedly affected the forms of Cd found in the columns as well as its vertical migration rate. The Cd accumulated in the four media was mainly in residual form; moreover, accumulation of Cd occurred mainly in the surface layer of the bioretention column. The migration depth of Cd in the four media increased with elapsed time, in the following sequence: zeolite > quartz sand > fine sand > sand. In contrast, the migration rate decreased with elapsed time, and the migration rate of Cd was lowest in sand (0.015 m per annum over the first ten years). The comprehensive risk index analysis indicated that the risk arising from Cd discharge to surface water was "intermediate", and that the degree of risk was lowest in sand, then quartz sand, zeolite, and fine sand in sequence. These results indicate that the adsorption and accumulation of Cd in the four media are more significant than the migration of Cd. In addition, the results of Cd risk assessment for the effluent indicate that each of the four media can serve as long-term adsorption material in a bioretention facility for purifying stormwater runoff.

  8. The green build-out model : quantifying stormwater benefits of trees and green roofs in Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    Deutsch, B.; Whitlow, H. [Casey Trees, Washington, DC (United States); Sullivan, M.; Savineau, A.; Busiek, B. [Limno-Tech Inc., Ann Arbor, MI (United States)

    2007-07-01

    The United States Environmental Protection Agency has listed nearly all of the waters in the District of Columbia as impaired. This includes the Anacostia and Potomac rivers and Rock Creek, whose primary sources of pollution are sewer overflows and stormwater. This paper presented the research findings from the Environmental Protection Agency's Water Quality Cooperative Agreement grant entitled the Green Build-out Model. It builds upon research conducted by a public-private partnership between Casey Trees, a non-profit organization that protects tree cover in Washington DC, and Limno-Tech Inc., an environmental engineering firm that built the hydrologic and hydraulic model for the Water and Sewer Authority. Both green roofs and trees lower the volume of runoff, reduce peak rates of runoff, and improve water quality. However, these benefits have not been evaluated nor quantified on a cumulative, sewershed and city-wide basis for engineers, landscape architects, and planners to integrate green roofs and trees into solutions for stormwater permitting requirements. This research questioned how many green roofs and trees are needed to make a difference to stormwater management in the District of Columbia. It investigated the relationships between tree cover, green roof cover, larger tree boxes, and key hydrologic and hydraulic variables such as stormwater and combined sewer overflow volume, flow rate, and frequency. Reductions in pollutant loads resulting from lower stormwater volumes were also estimated along with operational savings from reduced pumping and treatment of stormwater volumes. All of the modeled green roofs were extensive green roofs with three to four inches of growth media. Extensive green roofs were assumed city-wide for their potential to reduce pollutant load from stormwater flow; operational savings from stormwater flow reductions; and, general hydrologic relationships. It was concluded that trees and green roofs should be factored into the

  9. Evaluation of the capability of low-impact development practices for the removal of heavy metal from urban stormwater runoff.

    Science.gov (United States)

    Maniquiz-Redillas, Marla C; Kim, Lee-Hyung

    2016-09-01

    Low-impact development (LID) and green infrastructure (GI) have recently become well-known methods to capture, collect, retain, and remove pollutants in stormwater runoff. The research was conducted to assess the efficiency of LID/GI systems applied in removing the particulate and dissolved heavy metals (Zn, Pb, Cu, Ni, Cr, Cd, and Fe) from urban stormwater runoff. A total of 82 storm events were monitored over a four-year period (2010-2014) on six LID/GI systems including infiltration trenches, tree box filter, rain garden, and hybrid constructed wetlands employed for the management of road, parking lot, and roof runoff. It was observed that the heavy metal concentration increased proportionally with the total suspended solids concentration. Among the heavy metal constituents, Fe appeared to be highly particulate-bound and was the easiest to remove followed by Zn and Pb; while metals such as Cr, Ni, Cu, and Cd were mostly dissolved and more difficult to remove. The mass fraction ratios of metal constituents at the effluent were increased relative to the influent. All the systems performed well in the removal of particulate-bound metals and were more efficient for larger storms greater than 15 mm wherein more particulate-bound metals were generated compared to smaller storms less than 5 mm that produced more dissolved metals. The efficiency of the systems in removing the particulate-bound metals was restricted during high average/peak flows; that is, high-intensity storms events and when heavy metals have low concentration levels.

  10. Stormwater infiltration trenches: a conceptual modelling approach.

    Science.gov (United States)

    Freni, Gabriele; Mannina, Giorgio; Viviani, Gaspare

    2009-01-01

    In recent years, limitations linked to traditional urban drainage schemes have been pointed out and new approaches are developing introducing more natural methods for retaining and/or disposing of stormwater. These mitigation measures are generally called Best Management Practices or Sustainable Urban Drainage System and they include practices such as infiltration and storage tanks in order to reduce the peak flow and retain part of the polluting components. The introduction of such practices in urban drainage systems entails an upgrade of existing modelling frameworks in order to evaluate their efficiency in mitigating the impact of urban drainage systems on receiving water bodies. While storage tank modelling approaches are quite well documented in literature, some gaps are still present about infiltration facilities mainly dependent on the complexity of the involved physical processes. In this study, a simplified conceptual modelling approach for the simulation of the infiltration trenches is presented. The model enables to assess the performance of infiltration trenches. The main goal is to develop a model that can be employed for the assessment of the mitigation efficiency of infiltration trenches in an integrated urban drainage context. Particular care was given to the simulation of infiltration structures considering the performance reduction due to clogging phenomena. The proposed model has been compared with other simplified modelling approaches and with a physically based model adopted as benchmark. The model performed better compared to other approaches considering both unclogged facilities and the effect of clogging. On the basis of a long-term simulation of six years of rain data, the performance and the effectiveness of an infiltration trench measure are assessed. The study confirmed the important role played by the clogging phenomenon on such infiltration structures.

  11. Stormwater Attenuation by Green Roofs

    Science.gov (United States)

    Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.

    2014-12-01

    Innovative municipal stormwater management technologies are urgently required in urban centers. Inadequate stormwater management can lead to excessive flooding, channel erosion, decreased stream baseflows, and degraded water quality. A major source of urban stormwater is unused roof space. Green roofs can be used as a stormwater management tool to reduce roof generated stormwater and generally improve the quality of runoff. With recent legislation in some North American cities, including Toronto, requiring the installation of green roofs on large buildings, research on the effectiveness of green roofs for stormwater management is important. This study aims to assess the hydrologic response of an extensive sedum green roof in London, Ontario, with emphasis on the response to large precipitation events that stress municipal stormwater infrastructure. A green roof rapidly reaches field capacity during large storm events and can show significantly different behavior before and after field capacity. At field capacity a green roof has no capillary storage left for retention of stormwater, but may still be an effective tool to attenuate peak runoff rates by transport through the green roof substrate. The attenuation of green roofs after field capacity is linked to gravity storage, where gravity storage is the water that is temporarily stored and can drain freely over time after field capacity has been established. Stormwater attenuation of a modular experimental green roof is determined from water balance calculations at 1-minute intervals. Data is used to evaluate green roof attenuation and the impact of field capacity on peak flow rates and gravity storage. In addition, a numerical model is used to simulate event based stormwater attenuation. This model is based off of the Richards equation and supporting theory of multiphase flow through porous media.

  12. Parking Lot Runoff Quality and Treatment Efficiency of a Stormwater-Filtration Device, Madison, Wisconsin, 2005-07

    Science.gov (United States)

    Horwatich, Judy A.; Bannerman, Roger T.

    2010-01-01

    To evaluate the treatment efficiency of a stormwater-filtration device (SFD) for potential use at Wisconsin Department of Transportation (WisDOT) park-and-ride facilities, a SFD was installed at an employee parking lot in downtown Madison, Wisconsin. This type of parking lot was chosen for the test site because the constituent concentrations and particle-size distributions (PSDs) were expected to be similar to those of a typical park-and-ride lot operated by WisDOT. The objective of this particular installation was to reduce loads of total suspended solids (TSS) in stormwater runoff to Lake Monona. This study also was designed to provide a range of treatment efficiencies expected for a SFD. Samples from the inlet and outlet were analyzed for 33 organic and inorganic constituents, including 18 polycyclic aromatic hydrocarbons (PAHs). Samples were also analyzed for physical properties, including PSD. Water-quality samples were collected for 51 runoff events from November 2005 to August 2007. Samples from all runoff events were analyzed for concentrations of suspended sediment (SS). Samples from 31 runoff events were analyzed for 15 constituents, samples from 15 runoff events were analyzed for PAHs, and samples from 36 events were analyzed for PSD. The treatment efficiency of the SFD was calculated using the summation of loads (SOL) and the efficiency ratio methods. Constituents for which the concentrations and (or) loads were decreased by the SFD include TSS, SS, volatile suspended solids, total phosphorous (TP), total copper, total zinc, and PAHs. The efficiency ratios for these constituents are 45, 37, 38, 55, 22, 5, and 46 percent, respectively. The SOLs for these constituents are 32, 37, 28, 36, 23, 8, and 48 percent, respectively. The SOL for chloride was -21 and the efficiency ratio was -18. Six chemical constituents or properties-dissolved phosphorus, chemical oxygen demand, dissolved zinc, total dissolved solids, dissolved chemical oxygen demand, and

  13. Modelling the fate of organic micropollutants in stormwater ponds

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Eriksson, Eva; Ledin, Anna;

    2011-01-01

    substance inherent properties to calculate MP fate but differ in their ability to represent the small physical scale and high temporal variability of stormwater treatment systems. Therefore the three models generate different results. A Global Sensitivity Analysis (GSA) highlighted that settling....../resuspension of particulate matter was themost sensitive process for the dynamic model. The uncertainty of the estimated MP fluxes can be reduced by calibrating the dynamic model against total suspended solids data. This reduction in uncertainty was more significant for the substances with strong tendency to sorb, i...... models. The fate of four different MP in a stormwater retention pond was simulated by applying two steady-state multimedia fate models (EPI Suite and SimpleBox) commonly applied in chemical risk assessment and a dynamic multimedia fate model (Stormwater Treatment Unit Model for Micro Pollutants — STUMP...

  14. Improving Urban Stormwater Runoff Quality by Nutrient Removal through Floating Treatment Wetlands and Vegetation Harvest

    OpenAIRE

    Xu, Bing; Wang, Xue; Liu, Jia; Wu, Jiaqiang; Zhao, Yongjun; Cao, Weixing

    2017-01-01

    Two floating treatment wetlands (FTWs) in experimental tanks were compared in terms of their effectiveness on removing nutrients. The results showed that the FTWs were dominated by emergent wetland plants and were constructed to remove nutrients from simulated urban stormwater. Iris pseudacorus and Thalia dealbata wetland systems were effective in reducing the nutrient. T. dealbata FTWs showed higher nutrient removal performance than I. pseudacorus FTWs. Nitrogen (N) and phosphorous (P) remov...

  15. Implementation of a monitoring system to measure impact of stormwater runoff infiltration.

    Science.gov (United States)

    Barraud, S; Gibert, J; Winiarski, T; Bertrand Krajewski, J L

    2002-01-01

    Stormwater infiltration is a drainage mode, which is more and more used in urban areas in France. Given the characteristics of urban surfaces, and especially the loads of various pollutants contained in stormwater, it is important to assess the impact of stormwater infiltration systems on soil and groundwater by carrying out field experiments. The main difficulty is due to the complexity of the system observed and the need of multidisciplinary approaches. Another difficulty is that measurements are carried out in situ, in an uncontrolled environment submitted to quantitatively and qualitatively highly variable interferences. Very long term monitoring is needed to get representative results. In order to contribute to solve these problems, the OTHU project has recently been launched in Lyon (France). One of its key action concerns a long-term (10 years) experiment on an infiltration basin specifically rehabilitated for measurements and operational drainage issues. This paper presents the experimental site, the objectives of the project and the way the monitoring process has been built according to the various disciplines involved (biology, ecology, hydrology, chemistry and soil sciences) and to the will of assessing all the uncertainties in the measurement process.

  16. Uncertainty-based calibration and prediction with a stormwater surface accumulation-washoff model based on coverage of sampled Zn, Cu, Pb and Cd field data

    DEFF Research Database (Denmark)

    Lindblom, Erik Ulfson; Ahlman, S.; Mikkelsen, Peter Steen

    2011-01-01

    μg/l ±80% for Pb and 0.6 μg/l ±35% for Cd. This uncertainty-based calibration procedure adequately describes the prediction uncertainty conditioned on the used model and data, but seasonal and site-to-site variation is not considered, i.e. predicting metal concentrations in stormwater runoff from...

  17. Water-quality data of stormwater runoff from Davenport, Iowa, 1992 and 1994

    Science.gov (United States)

    Schaap, B.D.; Einhellig, R.F.

    1996-01-01

    The Water Quality Act of 1987 required the U.S. Environmental Protection Agency to regulate stormwater discharges under the National Pollutant Discharge Elimination System program, and guidelines for obtaining permits under this program were established for areas served by municipal separate storm sewer systems with populations greater than 100,000 (U.S. Environmental Protection Agency, 1992a, 1992b). The City of Davenport, Iowa, and the U.S. Geological Survey cooperatively conducted a study designed to meet technical conditions of the permit application and to develop criteria for ongoing monitoring during the term of the permit.

  18. Reconnaissance of contaminants in selected wastewater-treatment-plant effluent and stormwater runoff entering the Columbia River, Columbia River Basin, Washington and Oregon, 2008-10

    Science.gov (United States)

    Morace, Jennifer L.

    2012-01-01

    Toxic contamination is a significant concern in the Columbia River Basin in Washington and Oregon. To help water managers and policy makers in decision making about future sampling efforts and toxic-reduction activities, a reconnaissance was done to assess contaminant concentrations directly contributed to the Columbia River through wastewater-treatment-plant (WWTP) effluent and stormwater runoff from adjacent urban environments and to evaluate instantaneous loadings to the Columbia River Basin from these inputs.

  19. Effects of storm-water runoff on water quality of the Edwards Aquifer near Austin, Texas

    Science.gov (United States)

    Andrews, Freeman L.; Schertz, Terry L.; Slade, Raymond M.; Rawson, Jack

    1984-01-01

    Analyses of samples collected from Barton Springs at approximately weekly Intervals and from Barton Creek and five wells in the Austin area during selected storm-runoff periods generally show that recharge during storm runoff resulted in significant temporal and area! variations in the quality of ground water in the recharge zone of the Edwards aquifer. Recharge during storm runoff resulted in significant increases of bacterial densities in the ground water. Densities of fecal coliform bacteria in samples collected from Barton Springs, the major point of ground-water discharge, ranged from less than 1 colony per 100 milliliters during dry weather in November 1981 and January and August 1982 to 6,100 colonies per 100 milliliters during a storm in May 1982. Densities of fecal streptococcal bacteria ranged from 1 colony per 100 miniliters during dry weather in December 1981 to 11,000 colonies per 100 miniliters during a storm in May 1982.

  20. Monitoring of priority pollutants in dynamic stormwater discharges from urban areas

    DEFF Research Database (Denmark)

    Birch, Heidi

    is always involved. This interpretation can be formulated in stormwater quality models. Event mean concentrations (EMCs) are often found to follow a lognormal distribution. However more complicated models including dynamics of accumulation in the catchment and influence of rain characteristics on the runoff......The European Water Framework Directive (WFD) from 2000 has put focus on the chemical status of surface waters by the specified Environmental Quality Standard (EQSs) and the requirements for monitoring of surface water quality throughout Europe. When considering the water quality of urban stormwater...... runoff it is evident that surface waters receiving large amount of urban stormwater runoff will be at risk of failing to meet the EQSs. Therefore stormwater treatment is crucial. However, as stormwater quality varies orders of magnitude between sites, stormwater monitoring is important in order to design...

  1. Semi- vs. Fully-Distributed Urban Stormwater Models: Model Set Up and Comparison with Two Real Case Studies

    Directory of Open Access Journals (Sweden)

    Rui Daniel Pina

    2016-02-01

    Full Text Available Urban stormwater models can be semi-distributed (SD or fully distributed (FD. SD models are based on subcatchment units with various land use types, where rainfall is applied and runoff volumes are estimated and routed. FD models are based on the two dimensional (2D discretization of the overland surface, which has a finer resolution with each grid-cell representing one land use type, where runoff volumes are estimated and directly routed by the 2D overland flow module. While SD models have been commonly applied in urban stormwater modeling, FD models are generally more detailed and theoretically more realistic. This paper presents a comparison between SD and FD models using two case studies in Coimbra (Portugal and London (UK. To enable direct comparison between SD and FD setups, a model-building process is proposed and a novel sewer inlet representation is applied. SD and FD modeling results are compared against observed records in sewers and photographic records of flood events. The results suggest that FD models are more sensitive to surface storage parameters and require higher detail of the sewer network representation.

  2. Water quality and zooplankton composition in a receiving pond of the stormwater runoff from an urban catchment.

    Science.gov (United States)

    Jose de Paggi, Susana; Paggi, Juan; Collins, Pablo; Collins, Jorge; Graciela, Bernal

    2008-09-01

    Six storm periods were monitored from November 2002 to September 2005 at two stations of a receiving pond of the stormwater runoff from a small urban catchment of the city of Santa Fe, Argentina. Weekly samples were taken before and after rain events under different conditions of temperature, pluvial precipitation, and duration of the previous dry period. A sampling station was established at the outlet of the catchment (S1) and another one near the outlet of the receiving pond (S2). Both stations differed significantly in their dissolved oxygen (DO) concentration, temperature, transparency, and zooplankton composition. The concentrations of nutrients and BOD5 values indicated permanently eutrophic condition at both stations. After rainstorms, the concentrations of lead, zinc and suspended solids showed a marked increase. The zooplankton composition at S1 was characterized by the abundance of protozoans (Dexiostoma campylum (Stokes) Didinium nasutum Muller, Plagyopila cf nasuta, and Bdelloidea rotifers (Philodina sp and Rotaria sp), while Monogononta rotifers and small cladocerans were dominant at S2. The most abundant species were the rotifers Platyias quadricornis (Ehrenberg), Mytilina ventralis (Ehrenberg) and Lepadella ovalis (Muller), and the cladoceran Chydorus pubescens Sars.

  3. Effects of Stormwater and Snowmelt Runoff on ELISA-EQ Concentrations of PCDD/PCDF and Triclosan in an Urban River

    Science.gov (United States)

    Urbaniak, Magdalena; Tygielska, Adrianna; Krauze, Kinga; Mankiewicz-Boczek, Joanna

    2016-01-01

    The aim of the study was to determine the effects of stormwater and snowmelt runoff on the ELISA EQ PCDD/PCDF and triclosan concentrations in the small urban Sokołówka River (Central Poland). The obtained results demonstrate the decisive influence of hydrological conditions occurring in the river itself and its catchment on the quoted PCDD/PCDF ELISA EQ concentrations. The lowest PCDD/PCDF values of 87, 60 and 67 ng EQ L-1 in stormwater, the river and its reservoirs, respectively, were associated with the highest river flow of 0.02 m3 s-1 and high precipitation (11.2 mm) occurred five days before sampling. In turn, the highest values of 353, 567 and 343 ng EQ L-1 in stormwater, the river and its reservoirs, respectively, were observed during periods of intensive snow melting (stormwater samples) and spring rainfall preceded by a rainless phase (river and reservoir samples) followed by low and moderate river flows of 0.01 and 0.005 m3 s-1. An analogous situation was observed for triclosan, with higher ELISA EQ concentrations (444 to 499 ng EQ L-1) noted during moderate river flow and precipitation, and the lowest (232 to 288 ng EQ L-1) observed during high river flow and high precipitation preceded by violent storms. Stormwater was also found to influence PCDD/PCDF EQ concentrations of the river and reservoirs, however only during high and moderate flow, and no such effect was observed for triclosan. The study clearly demonstrates that to mitigate the high peaks of the studied pollutants associated with river hydrology, the increased in-site stormwater infiltration and purification, the development of buffering zones along river course and the systematic maintenance of reservoirs to avoid the accumulation of the studied micropollutants and their subsequent release after heavy rainfall are required. PMID:26985830

  4. Effects of Stormwater and Snowmelt Runoff on ELISA-EQ Concentrations of PCDD/PCDF and Triclosan in an Urban River.

    Directory of Open Access Journals (Sweden)

    Magdalena Urbaniak

    Full Text Available The aim of the study was to determine the effects of stormwater and snowmelt runoff on the ELISA EQ PCDD/PCDF and triclosan concentrations in the small urban Sokołówka River (Central Poland. The obtained results demonstrate the decisive influence of hydrological conditions occurring in the river itself and its catchment on the quoted PCDD/PCDF ELISA EQ concentrations. The lowest PCDD/PCDF values of 87, 60 and 67 ng EQ L-1 in stormwater, the river and its reservoirs, respectively, were associated with the highest river flow of 0.02 m3 s-1 and high precipitation (11.2 mm occurred five days before sampling. In turn, the highest values of 353, 567 and 343 ng EQ L-1 in stormwater, the river and its reservoirs, respectively, were observed during periods of intensive snow melting (stormwater samples and spring rainfall preceded by a rainless phase (river and reservoir samples followed by low and moderate river flows of 0.01 and 0.005 m3 s-1. An analogous situation was observed for triclosan, with higher ELISA EQ concentrations (444 to 499 ng EQ L-1 noted during moderate river flow and precipitation, and the lowest (232 to 288 ng EQ L-1 observed during high river flow and high precipitation preceded by violent storms. Stormwater was also found to influence PCDD/PCDF EQ concentrations of the river and reservoirs, however only during high and moderate flow, and no such effect was observed for triclosan. The study clearly demonstrates that to mitigate the high peaks of the studied pollutants associated with river hydrology, the increased in-site stormwater infiltration and purification, the development of buffering zones along river course and the systematic maintenance of reservoirs to avoid the accumulation of the studied micropollutants and their subsequent release after heavy rainfall are required.

  5. Effects of Stormwater and Snowmelt Runoff on ELISA-EQ Concentrations of PCDD/PCDF and Triclosan in an Urban River.

    Science.gov (United States)

    Urbaniak, Magdalena; Tygielska, Adrianna; Krauze, Kinga; Mankiewicz-Boczek, Joanna

    2016-01-01

    The aim of the study was to determine the effects of stormwater and snowmelt runoff on the ELISA EQ PCDD/PCDF and triclosan concentrations in the small urban Sokołówka River (Central Poland). The obtained results demonstrate the decisive influence of hydrological conditions occurring in the river itself and its catchment on the quoted PCDD/PCDF ELISA EQ concentrations. The lowest PCDD/PCDF values of 87, 60 and 67 ng EQ L-1 in stormwater, the river and its reservoirs, respectively, were associated with the highest river flow of 0.02 m3 s-1 and high precipitation (11.2 mm) occurred five days before sampling. In turn, the highest values of 353, 567 and 343 ng EQ L-1 in stormwater, the river and its reservoirs, respectively, were observed during periods of intensive snow melting (stormwater samples) and spring rainfall preceded by a rainless phase (river and reservoir samples) followed by low and moderate river flows of 0.01 and 0.005 m3 s-1. An analogous situation was observed for triclosan, with higher ELISA EQ concentrations (444 to 499 ng EQ L-1) noted during moderate river flow and precipitation, and the lowest (232 to 288 ng EQ L-1) observed during high river flow and high precipitation preceded by violent storms. Stormwater was also found to influence PCDD/PCDF EQ concentrations of the river and reservoirs, however only during high and moderate flow, and no such effect was observed for triclosan. The study clearly demonstrates that to mitigate the high peaks of the studied pollutants associated with river hydrology, the increased in-site stormwater infiltration and purification, the development of buffering zones along river course and the systematic maintenance of reservoirs to avoid the accumulation of the studied micropollutants and their subsequent release after heavy rainfall are required.

  6. Calibration of stormwater management model using flood extent data

    OpenAIRE

    Han, Kunyeun; Kim, YoungJoo; Kim, Byunhyun; Famiglietti, James S.; Sanders, Brett F.

    2014-01-01

    The Seogu (western) portion of Daegu, Korea experiences chronic urban flooding and there is a need to increase flood detention and storage to reduce flood impacts. Since the site is densely developed, use of an underground car park as a cistern has been proposed. The stormwater management model (SWMM) is applied to study alternative hydraulic designs and overall performance, and it is shown that by linking SWMM to a two-dimensional flood inundation model, SWMM parameters can be calibrated fro...

  7. Improving Urban Stormwater Runoff Quality by Nutrient Removal through Floating Treatment Wetlands and Vegetation Harvest.

    Science.gov (United States)

    Xu, Bing; Wang, Xue; Liu, Jia; Wu, Jiaqiang; Zhao, Yongjun; Cao, Weixing

    2017-08-01

    Two floating treatment wetlands (FTWs) in experimental tanks were compared in terms of their effectiveness on removing nutrients. The results showed that the FTWs were dominated by emergent wetland plants and were constructed to remove nutrients from simulated urban stormwater. Iris pseudacorus and Thalia dealbata wetland systems were effective in reducing the nutrient. T. dealbata FTWs showed higher nutrient removal performance than I. pseudacorus FTWs. Nitrogen (N) and phosphorous (P) removal rates in water by T. dealbata FTWs were 3.95 ± 0.19 and 0.15 ± 0.01 g/m(2)/day, respectively. For I. pseudacorus FTWs, the TN and TP removal rates were 3.07 ± 0.15 and 0.14 ± 0.01 g/m(2)/day, respectively. The maximum absolute growth rate for T. dealbata corresponded directly with the maximum mean nutrient removal efficiency during the 5th stage. At harvest, N and P uptak of T. dealbata was 23.354 ± 1.366 g and 1.489 ± 0.077 g per plant, respectively, approximate twice as high as by I. pseudacorus.

  8. Assessment of Drywells as Effective Tools for Stormwater Management and Aquifer Recharge: Results of a Two-Year Field and Numerical Modeling Study

    Science.gov (United States)

    Edwards, E.; Washburn, B.; Harter, T.; Fogg, G. E.; Nelson, C.; Lock, B.; Li, X.

    2016-12-01

    Drywells are gravity-fed, excavated pits with perforated casings used to facilitate stormwater infiltration and groundwater recharge in areas with low permeability soils or cover. Stormwater runoff that would otherwise be routed to streams or drains in urban areas can be used as a source of aquifer recharge, potentially mitigating the effects of drought and harm to natural water bodies. However, the potential for groundwater contamination caused by urban runoff bypassing surface soil and near surface sediment attenuation processes has prevented more widespread use of drywells as a recharge mechanism. A field study was conducted in Elk Grove, CA, to determine the effects of drywell-induced stormwater infiltration on the local hydrogeologic system. Two drywells 13.5 meters in depth were constructed for the project: one in a preexisting drainage basin fed by residential lots, and one at an industrial site. Both sites were outfitted with vegetated pretreatments, and upgradient and downgradient groundwater monitoring wells. Site stormwater and groundwater were sampled between November, 2014, and May, 2016, and analyzed for contaminants. Results of water quality sampling have been statistically analyzed for trends and used to determine the contaminants of interest and the concentrations of these contaminants in influent stormwater. The fate and transport of these contaminants have been simulated using a 1D variably saturated flow and transport model and site specific parameters to predict long-term effects of stormwater infiltration on the surrounding hydrogeologic system. The potential for remobilization of geogenic heavy metals from changes in subsurface hydrochemistry caused by drywell infiltration have also been assessed. The results of the field study and numerical modeling assessment indicate that the study's drywells do not pose a long-term threat to groundwater quality and may be an effective source of aquifer recharge and tool for urban stormwater management.

  9. Dracaena marginata biofilter: design of growth substrate and treatment of stormwater runoff.

    Science.gov (United States)

    Vijayaraghavan, K; Praveen, R S

    2016-01-01

    The purpose of this research was to investigate the efficiency of Dracaena marginata planted biofilters to decontaminate urban runoff. A new biofilter growth substrate was prepared using low-cost and locally available materials such as red soil, fine sand, perlite, vermiculite, coco-peat and Sargassum biomass. The performance of biofilter substrate was compared with local garden soil based on physical and water quality parameters. Preliminary analyses indicated that biofilter substrate exhibited desirable characteristics such as low bulk density (1140 kg/m(3)), high water holding capacity (59.6%), air-filled porosity (7.82%) and hydraulic conductivity (965 mm/h). Four different biofilter assemblies, with vegetated and non-vegetated systems, were examined for several artificial rain events (un-spiked and metal-spiked). Results from un-spiked artificial rain events suggested that concentrations of most of the chemical components in effluent were highest at the beginning of rain events and thereafter subsided during the subsequent rain events. Biofilter growth substrate showed superior potential over garden soil to retain metal ions such as Al, Fe, Cu, Cr, Ni, Zn, Cd and Pb during metal-spiked rain events. Significant differences were also observed between non-vegetated and vegetated biofilter assemblies in runoff quality, with the latter producing better results.

  10. Identification and induction of human, social, and cultural capitals through an experimental approach to stormwater management

    Science.gov (United States)

    Decentralized stormwater management is based on the dispersal of stormwater management practices (SWMP) throughout a watershed to manage stormwater runoff volume and potentially restore natural hydrologic processes. This approach to stormwater management is increasingly popular b...

  11. Identification and induction of human, social, and cultural capitals through an experimental approach to stormwater management

    Science.gov (United States)

    Decentralized stormwater management is based on the dispersal of stormwater management practices (SWMP) throughout a watershed to manage stormwater runoff volume and potentially restore natural hydrologic processes. This approach to stormwater management is increasingly popular b...

  12. Enhancing a rainfall-runoff model to assess the impacts of BMPs and LID practices on storm runoff.

    Science.gov (United States)

    Liu, Yaoze; Ahiablame, Laurent M; Bralts, Vincent F; Engel, Bernard A

    2015-01-01

    Best management practices (BMPs) and low impact development (LID) practices are increasingly being used as stormwater management techniques to reduce the impacts of urban development on hydrology and water quality. To assist planners and decision-makers at various stages of development projects (planning, implementation, and evaluation), user-friendly tools are needed to assess the effectiveness of BMPs and LID practices. This study describes a simple tool, the Long-Term Hydrologic Impact Assessment-LID (L-THIA-LID), which is enhanced with additional BMPs and LID practices, improved approaches to estimate hydrology and water quality, and representation of practices in series (meaning combined implementation). The tool was used to evaluate the performance of BMPs and LID practices individually and in series with 30 years of daily rainfall data in four types of idealized land use units and watersheds (low density residential, high density residential, industrial, and commercial). Simulation results were compared with the results of other published studies. The simulated results showed that reductions in runoff volume and pollutant loads after implementing BMPs and LID practices, both individually and in series, were comparable with the observed impacts of these practices. The L-THIA-LID 2.0 model is capable of assisting decision makers in evaluating environmental impacts of BMPs and LID practices, thereby improving the effectiveness of stormwater management decisions.

  13. Modelling the impact of retention–detention units on sewer surcharge and peak and annual runoff reduction

    DEFF Research Database (Denmark)

    Locatelli, Luca; Gabriel, S.; Mark, O.

    2015-01-01

    Stormwater management using water sensitive urban design is expected to be part of future drainage systems. This paper aims to model the combination of local retention units, such as soakaways, with subsurface detention units. Soakaways are employed to reduce (by storage and infiltration) peak...... and volume stormwater runoff; however, large retention volumes are required for a significant peak reduction. Peak runoff can therefore be handled by combining detention units with soakaways. This paper models the impact of retrofitting retention-detention units for an existing urbanized catchment in Denmark....... The impact of retrofitting a retention-detention unit of 3.3 m(3)/100 m(2) (volume/impervious area) was simulated for a small catchment in Copenhagen using MIKE URBAN. The retention-detention unit was shown to prevent flooding from the sewer for a 10-year rainfall event. Statistical analysis of continuous...

  14. Velocity dependent passive sampling for monitoring of micropollutants in dynamic stormwater discharges

    DEFF Research Database (Denmark)

    Birch, Heidi; Sharma, Anitha Kumari; Vezzaro, Luca

    2013-01-01

    -ideal for sampling such systems because they sample in a time-integrative manner. This paper reports test of a flow-through passive sampler, deployed in stormwater runoff at the outlet of a residential-industrial catchment. Momentum from the water velocity during runoff events created flow through the sampler...... resulting in velocity dependent sampling. This approach enables the integrative sampling of stormwater runoff during periods of weeks to months while weighting actual runoff events higher than no flow periods. Results were comparable to results from volume-proportional samples and results obtained from...... using a dynamic stormwater quality model (DSQM). The paper illustrates how velocity-dependent flow-through passive sampling may revolutionize the way stormwater discharges are monitored. It also opens the possibility to monitor a larger range of discharge sites over longer time periods instead...

  15. Adaptive Urban Stormwater Management Using a Two-stage Stochastic Optimization Model

    Science.gov (United States)

    Hung, F.; Hobbs, B. F.; McGarity, A. E.

    2014-12-01

    In many older cities, stormwater results in combined sewer overflows (CSOs) and consequent water quality impairments. Because of the expense of traditional approaches for controlling CSOs, cities are considering the use of green infrastructure (GI) to reduce runoff and pollutants. Examples of GI include tree trenches, rain gardens, green roofs, and rain barrels. However, the cost and effectiveness of GI are uncertain, especially at the watershed scale. We present a two-stage stochastic extension of the Stormwater Investment Strategy Evaluation (StormWISE) model (A. McGarity, JWRPM, 2012, 111-24) to explicitly model and optimize these uncertainties in an adaptive management framework. A two-stage model represents the immediate commitment of resources ("here & now") followed by later investment and adaptation decisions ("wait & see"). A case study is presented for Philadelphia, which intends to extensively deploy GI over the next two decades (PWD, "Green City, Clean Water - Implementation and Adaptive Management Plan," 2011). After first-stage decisions are made, the model updates the stochastic objective and constraints (learning). We model two types of "learning" about GI cost and performance. One assumes that learning occurs over time, is automatic, and does not depend on what has been done in stage one (basic model). The other considers learning resulting from active experimentation and learning-by-doing (advanced model). Both require expert probability elicitations, and learning from research and monitoring is modelled by Bayesian updating (as in S. Jacobi et al., JWRPM, 2013, 534-43). The model allocates limited financial resources to GI investments over time to achieve multiple objectives with a given reliability. Objectives include minimizing construction and O&M costs; achieving nutrient, sediment, and runoff volume targets; and community concerns, such as aesthetics, CO2 emissions, heat islands, and recreational values. CVaR (Conditional Value at Risk) and

  16. Partitioning of fluoranthene between free and bound forms in stormwater runoff and other urban discharges using passive dosing

    DEFF Research Database (Denmark)

    Birch, Heidi; Mayer, Philipp; Lützhøft, Hans-Christian Holten;

    2012-01-01

    of the different stormwater samples for carrying fluoranthene was 2–23 relative to pure water and decreasing during rain events. The enhanced capacity of stormwater showed a different relationship with suspended solid concentrations than the other types of urban discharges. Partitioning of fluoranthene...... treatment systems. This work also shows the potential of the passive dosing method to obtain conversion factors between total concentrations, which are needed for comparison with water quality criteria, and freely dissolved concentrations, which are more related to toxicity and obtained by the use of most...

  17. Blue and green infrastructures implementation to solve stormwater management issues in a new urban development project - a modelling approach

    Science.gov (United States)

    Versini, Pierre-Antoine; Tchiguirinskaia, Ioulia; Schertzer, Daniel

    2016-04-01

    Concentrating buildings and socio-economic activities, urban areas are particularly vulnerable to hydrological risks. Modification in climate may intensify already existing issues concerning stormwater management (due to impervious area) and water supply (due to the increase of the population). In this context, water use efficiency and best water management practices are key-issues in the urban environment already stressed. Blue and green infrastructures are nature-based solutions that provide synergy of the blue and green systems to provide multifunctional solutions and multiple benefits: increased amenity, urban heat island improvement, biodiversity, reduced energy requirements... They are particularly efficient to reduce the potential impact of new and existing developments with respect to stormwater and/or water supply issues. The Multi-Hydro distributed rainfall-runoff model represents an adapted tool to manage the impacts of such infrastructures at the urban basin scale. It is a numerical platform that makes several models interact, each of them representing a specific portion of the water cycle in an urban environment: surface runoff and infiltration depending on a land use classification, sub-surface processes and sewer network drainage. Multi-Hydro is still being developed at the Ecole des Ponts (open access from https://hmco.enpc.fr/Tools-Training/Tools/Multi-Hydro.php) to take into account the wide complexity of urban environments. The latest advancements have made possible the representation of several blue and green infrastructures (green roof, basin, swale). Applied in a new urban development project located in the Paris region, Multi-Hydro has been used to simulate the impact of blue and green infrastructures implementation. It was particularly focused on their ability to fulfil regulation rules established by local stormwater managers in order to connect the parcel to the sewer network. The results show that a combination of several blue and green

  18. Evaluation of Distributed BMPs in an Urban Watershed - High Resolution Modeling for Stormwater Management

    Science.gov (United States)

    Fry, T. J.; Maxwell, R. M.; McCray, J. E.; Higgins, C. P.

    2015-12-01

    Urbanization presents challenging water resource problems for communities worldwide. The hydromodifications associated with urbanization results in increased runoff rates and volumes and increased peak flows which can lead to increased erosion and stream destabilization, decreased evapotranspiration, decreased ground water recharge, increases in pollutant loading, and localized anthropogenic climate change or Urban Heat Islands. Stormwater management is shifting from a drainage-efficiency focus to a natural systems focus. The natural system focus, referred to as Low Impact Development (LID), or Green Infrastructure, uses best management practices (BMPs) to reduce the impacts caused by urbanization hydromodification. Currently there are two modeling approaches used to evaluate BMPs in urban watersheds, conceptually-based coarse resolution hydrologic models and high-resolution physically-based models. Conceptual urban hydrology-hydraulic models typically are used to determine peak flow hydrographs within a watershed based on uniform rainfall, the basins size, shape, and percent of impervious land cover. Physically-based hydrologic models simulate integrated surface and subsurface water flow. Here, we use high-resolution physically based hydrologic models of the urban hydrologic cycle with explicit inclusion of the built environment. We compare the inclusion and exclusion of LID features to evaluate the parameterizations used to model these components in more conceptually based models. Differences in response are discussed and a road map is put forth for improving LID representation in commonly used urban water models.

  19. Precipitation-runoff modeling system; user's manual

    Science.gov (United States)

    Leavesley, G.H.; Lichty, R.W.; Troutman, B.M.; Saindon, L.G.

    1983-01-01

    The concepts, structure, theoretical development, and data requirements of the precipitation-runoff modeling system (PRMS) are described. The precipitation-runoff modeling system is a modular-design, deterministic, distributed-parameter modeling system developed to evaluate the impacts of various combinations of precipitation, climate, and land use on streamflow, sediment yields, and general basin hydrology. Basin response to normal and extreme rainfall and snowmelt can be simulated to evaluate changes in water balance relationships, flow regimes, flood peaks and volumes, soil-water relationships, sediment yields, and groundwater recharge. Parameter-optimization and sensitivity analysis capabilites are provided to fit selected model parameters and evaluate their individual and joint effects on model output. The modular design provides a flexible framework for continued model system enhancement and hydrologic modeling research and development. (Author 's abstract)

  20. National Stormwater Calculator: Low Impact Development Stormwater Control Cost Estimation Programming & Future Enhancements - abstract

    Science.gov (United States)

    The National Stormwater Calculator (NSC) makes it easy to estimate runoff reduction when planning a new development or redevelopment site with low impact development (LID) stormwater controls. The Calculator is currently deployed as a Windows desktop application. The Calculator i...

  1. Modeling Rainfall-Runoff Dynamics in Tropical, Urban Socio-Hydrological Systems: Green Infrastructure and Variable Precipitation Interception

    Science.gov (United States)

    Nytch, C. J.; Meléndez-Ackerman, E. J.

    2014-12-01

    There is a pressing need to generate spatially-explicit models of rainfall-runoff dynamics in the urban humid tropics that can characterize flow pathways and flood magnitudes in response to erratic precipitation events. To effectively simulate stormwater runoff processes at multiple scales, complex spatio-temporal parameters such as rainfall, evapotranspiration, and antecedent soil moisture conditions must be accurately represented, in addition to uniquely urban factors including stormwater conveyance structures and connectivity between green and gray infrastructure elements. In heavily urbanized San Juan, Puerto Rico, stream flashiness and frequent flooding are major issues, yet still lacking is a hydrological analysis that models the generation and movement of fluvial and pluvial stormwater through the watershed. Our research employs a novel and multifaceted approach to dealing with this problem that integrates 1) field-based rainfall interception and infiltration methodologies to quantify the hydrologic functions of natural and built infrastructure in San Juan; 2) remote sensing analysis to produce a fine-scale typology of green and gray cover types in the city and determine patterns of spatial distribution and connectivity; 3) assessment of precipitation and streamflow variability at local and basin-wide scales using satellite and radar precipitation estimates in concert with rainfall and stream gauge point data and participatory flood mapping; 4) simulation of historical, present-day, and future stormwater runoff scenarios with a fully distributed hydrologic model that couples diverse components of urban socio-hydrological systems from formal and informal knowledge sources; and 5) bias and uncertainty analysis of parameters and model structure within a Bayesian hierarchical framework. Preliminary results from the rainfall interception study suggest that canopy structure and leaf area index of different tree species contribute to variable throughfall and

  2. Polyurethane foam (PUF) passive samplers for monitoring phenanthrene in stormwater.

    Science.gov (United States)

    Dou, Yueqin; Zhang, Tian C; Zeng, Jing; Stansbury, John; Moussavi, Massoum; Richter-Egger, Dana L; Klein, Mitchell R

    2016-04-01

    Pollution from highway stormwater runoff has been an increasing area of concern. Many structural Best Management Practices (BMPs) have been implemented for stormwater treatment and management. One challenge for these BMPs is to sample stormwater and monitor BMP performance. The main objective of this study was to evaluate the feasibility of using polyurethane foam (PUF) passive samplers (PSs) for sampling phenanthrene (PHE) in highway stormwater runoff and BMPs. Tests were conducted using batch reactors, glass-tube columns, and laboratory-scale BMPs (bioretention cells). Results indicate that sorption for PHE by PUF is mainly linearly relative to time, and the high sorption capacity allows the PUF passive sampler to monitor stormwater events for months or years. The PUF passive samplers could be embedded in BMPs for monitoring influent and effluent PHE concentrations. Models developed to link the results of batch and column tests proved to be useful for determining removal or sorption parameters and performance of the PUF-PSs. The predicted removal efficiencies of BMPs were close to the real values obtained from the control columns with errors ranging between -8.46 and 1.52%. This research showed that it is possible to use PUF passive samplers for sampling stormwater and monitoring the performance of stormwater BMPs, which warrants the field-scale feasibility studies in the future.

  3. Comparison of different uncertainty techniques in urban stormwater quantity and quality modelling.

    Science.gov (United States)

    Dotto, Cintia B S; Mannina, Giorgio; Kleidorfer, Manfred; Vezzaro, Luca; Henrichs, Malte; McCarthy, David T; Freni, Gabriele; Rauch, Wolfgang; Deletic, Ana

    2012-05-15

    Urban drainage models are important tools used by both practitioners and scientists in the field of stormwater management. These models are often conceptual and usually require calibration using local datasets. The quantification of the uncertainty associated with the models is a must, although it is rarely practiced. The International Working Group on Data and Models, which works under the IWA/IAHR Joint Committee on Urban Drainage, has been working on the development of a framework for defining and assessing uncertainties in the field of urban drainage modelling. A part of that work is the assessment and comparison of different techniques generally used in the uncertainty assessment of the parameters of water models. This paper compares a number of these techniques: the Generalized Likelihood Uncertainty Estimation (GLUE), the Shuffled Complex Evolution Metropolis algorithm (SCEM-UA), an approach based on a multi-objective auto-calibration (a multialgorithm, genetically adaptive multi-objective method, AMALGAM) and a Bayesian approach based on a simplified Markov Chain Monte Carlo method (implemented in the software MICA). To allow a meaningful comparison among the different uncertainty techniques, common criteria have been set for the likelihood formulation, defining the number of simulations, and the measure of uncertainty bounds. Moreover, all the uncertainty techniques were implemented for the same case study, in which the same stormwater quantity and quality model was used alongside the same dataset. The comparison results for a well-posed rainfall/runoff model showed that the four methods provide similar probability distributions of model parameters, and model prediction intervals. For ill-posed water quality model the differences between the results were much wider; and the paper provides the specific advantages and disadvantages of each method. In relation to computational efficiency (i.e. number of iterations required to generate the probability

  4. Bacteria Removal from Stormwater Runoff Using Tree Filters: A Comparison of a Conventional and an Innovative System

    Directory of Open Access Journals (Sweden)

    Laura A. Schifman

    2016-03-01

    Full Text Available Non-point source pollution of stormwater contributes high contaminant loads into surface water bodies and poses a threat to the ecosystem, public health and economy. Although (pretreatment standards have not been introduced at the federal level, Rhode Island (RI has set minimal contaminant reduction standards for stormwater using structural best management practices (BMP. As BMP performance depends highly on geographical location and climate, and the Northeastern United States experiences broad ranges of temperatures throughout the year along with long intermittent periods between precipitation events, stormwater treatment can be challenging. In this field study, two tree filters were evaluated: a conventional unit (CTF with sand/shale mix as filter media, and a modified tree filter (ITF with an added layer of red cedar wood chips amended with 3-(trihydroxysilylpropyldimethyloctadecyl ammonium chloride. Both BMPs were monitored for 346 days primarily for Escherichia coli and polycyclic aromatic hydrocarbons (PAH. Both tree filters met or outperformed RI’s standards for bacteria removal (60% and TSS (85%, making them a good choice for BMP use in this climate. Total suspended solids, E. coli, PAHs, nitrate, and phosphate removal is higher in ITF. A controlled field scale tracer test using E. coli confirmed these results.

  5. MODELING OF STORM WATER RUNOFF FROM GREEN ROOFS

    OpenAIRE

    Ewa Burszta-Adamiak; Wiesław Fiałkiewicz

    2014-01-01

    Apart from direct measurements, modelling of runoff from green roofs is valuable source of information about effectiveness of this type of structure from hydrological point of view. Among different type of models, the most frequently used are numerical models. They allow to assess the impact of green roofs on decrease and attenuation of runoff, reduction of peak runoff and value of water retention. This paper presents preliminary results of research on computing the rate of runoff from green ...

  6. Assessment of runoff contributing catchment areas in rainfall runoff modelling

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Johansen, C.; Schaarup-Jensen, Kjeld

    2006-01-01

    recommended literature values for residential areas. It is proven by comparing rainfall-runoff measurements from four different residential catchments that the literature values of the hydrological reduction factor are over-estimated for this type of catchment. In addition, different catchment descriptions...... are presented in order to investigate how the hydrological reduction factor depends on the level of detail regarding the catchment description. When applying a total survey of the catchment area, including all possible impervious surfaces, a hydrological reduction factor of approximately 0.5 for residential...

  7. Assessment of Runoff Contributing Catchment Areas in Rainfall Runoff Modelling

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Johansen, C.; Schaarup-Jensen, Kjeld

    2005-01-01

    recommended literary values for residential areas. It is proven by comparing rainfall-runoff measurements from four different residential catchments that the literary values of the hydrological reduction factor are over-estimated for this type of catchments. In addition, different catchment descriptions...... are presented in order to investigate how the hydrological reduction factor depends on the level of detail regarding the catchment description. When applying a total survey of the catchment area, including all possible impervious surfaces, a hydrological reduction factor of approximately 0.5 for residential...

  8. Multifractal modelling of runoffs of karstic springs

    Science.gov (United States)

    Márkus, L.

    2003-04-01

    A new multifractal stochastic process, Terdik and Iglói call the Limit of the Integrated Superposition of Diffusion processes with Linear differential Generator (LISDLG) , has been defined for modelling network traffic multifractality. The process is stationary, and exhibits long range dependency or long memory. Its characteristic property is that its bispectrum is real. It serves as the basis of distinction e.g. from the superposition of Levy-processes driven Ornstein-Uhlenbeck processes. Its further appealing property is that its finite dimensional distribution stems from multivariate Gamma, therefore it is inherently positive and skewed (and hence non-Gaussian). All together, this makes it a very promising candidate for modelling e.g. runoff data of springs or river flows. Quite recently Labat et al. (2002, J. of Hydrology, Vol 256, pp.176-195) pointed out multifractal properties of the runoff time series of French karstic springs. We show that runoff data of karstic springs in north-east Hungary possesses multifractal and cumulant-multifractal property as well as long range dependency and fit the above described LISDLG process, to model the phenomenon. Acknowledgement: This research was supported by the Nat. Sci. Research Fund OTKA, grant No.: T 032725.

  9. System dynamics modeling of nitrogen removal in a stormwater infiltration basin with biosorption-activated media.

    Science.gov (United States)

    Xuan, Zhemin; Chang, Ni-Bin; Wanielista, Martin P; Williams, Evan Shane

    2013-07-01

    Stormwater infiltration basins, one of the typical stormwater best management practices, are commonly constructed for surface water pollution control, flood mitigation, and groundwater restoration in rural or residential areas. These basins have soils with better infiltration capacity than the native soil; however, the ever-increasing contribution of nutrients to groundwater from stormwater due to urban expansion makes existing infiltration basins unable to meet groundwater quality criteria related to environmental sustainability and public health. This issue requires retrofitting current infiltration basins for flood control as well as nutrient control before the stormwater enters the groundwater. An existing stormwater infiltration basin in north-central Florida was selected, retrofitted, and monitored to identify subsurface physiochemical and biological processes during 2007-2010 to investigate nutrient control processes. This implementation in the nexus of contaminant hydrology and ecological engineering adopted amended soil layers packed with biosorption activated media (BAM; tire crumb, silt, clay, and sand) to perform nutrient removal in a partitioned forebay using a berm. This study presents an infiltration basin-nitrogen removal (IBNR) model, a system dynamics model that simulates nitrogen cycling in this BAM-based stormwater infiltration basin with respect to changing hydrologic conditions and varying dissolved nitrogen concentrations. Modeling outputs of IBNR indicate that denitrification is the biogeochemical indicator in the BAM layer that accounted for a loss of about one third of the total dissolved nitrogen mass input.

  10. Water treatment residual (WTR)-coated wood mulch for alleviation of toxic metals and phosphorus from polluted urban stormwater runoff.

    Science.gov (United States)

    Soleimanifar, Hanieh; Deng, Yang; Wu, Laying; Sarkar, Dibyendu

    2016-07-01

    Aluminum-based water treatment residual (WTR)-coated wood mulches were synthesized and tested for removal of heavy metals and phosphorus (P) in synthetic urban stormwater. WTRs are an industrial waste produced from coagulation in water treatment facilities, primarily composed of amorphous aluminum or iron hydroxides. Batch tests showed that the composite filter media could effectively adsorb 97% lead (Pb), 76% zinc (Zn), 81% copper (Cu) and 97% P from the synthetic stormwater (Pb = 100 μg/L, Zn = 800 μg/L, Cu = 100 μg/L, P = 2.30 mg/L, and pH = 7.0) within 120 min, due to the presence of aluminum hydroxides as an active adsorbent. The adsorption was a 2(nd)-order reaction with respect toward each pollutant. Column tests demonstrated that the WTR-coated mulches considerably alleviated the select pollutants under a continuous-flow condition over the entire filtration period. The effluent Pb, Zn, Cu, and P varied at 0.5-8.9%, 33.4-46.7%, 45.8-55.8%, and 6.4-51.9% of their respective initial concentrations with the increasing bed volume from 0 to 50. Synthetic precipitation leaching procedure (SPLP) and toxicity characteristic leaching procedure (TCLP) tests indicated that leached contaminants were all below the U.S. criteria, suggesting that the release of undesired chemicals under rainfall or landfilling conditions is not a concern during application. This study demonstrates that the WTR-coated mulches are a new, low-cost, and effective filter media for urban stormwater treatment. Equally important, this study provides a sustainable approach to beneficially reuse an industrial waste for environmental pollution control.

  11. Metal concentrations in soil and seepage water due to infiltration of roof runoff by long term numerical modelling.

    Science.gov (United States)

    Zimmermann, J; Dierkes, C; Göbel, P; Klinger, C; Stubbe, H; Coldewey, W G

    2005-01-01

    The qualitative effects of stormwater infiltration on soil and seepage water are investigated with long term numerical modelling. The retention behaviour of different soils and materials used in infiltration devices is determined with batch and column tests. Results of the laboratory tests are adsorption isotherms which represent input data for numerical transport modelling. The long term simulations are performed with combinations of different solutions (types of roof runoff) and infiltration devices (swale and trench) under different hydrogeological conditions. The presented results contain the infiltration of low polluted roof runoff, runoff from a roof with zinc sheets and from a roof with copper sheets concerning the heavy metals zinc, copper and lead. The increase of concentrations in the infiltration body is high. For the infiltrated water, the results show a migration to groundwater only for the low adsorbing soil.

  12. NATIONAL STORMWATER CALCULATOR USER'S GUIDE ...

    Science.gov (United States)

    The National Stormwater Calculator is a simple to use tool for computing small site hydrology for any location within the US. It estimates the amount of stormwater runoff generated from a site under different development and control scenarios over a long term period of historical rainfall. The analysis takes into account local soil conditions, slope, land cover and meteorology. Different types of low impact development (LID) practices (also known as green infrastructure) can be employed to help capture and retain rainfall on-site. Future climate change scenarios taken from internationally recognized climate change projections can also be considered. The calculator provides planning level estimates of capital and maintenance costs which will allow planners and managers to evaluate and compare effectiveness and costs of LID controls.The calculator’s primary focus is informing site developers and property owners on how well they can meet a desired stormwater retention target. It can be used to answer such questions as:• What is the largest daily rainfall amount that can be captured by a site in either its pre-development, current, or post-development condition?• To what degree will storms of different magnitudes be captured on site?• What mix of LID controls can be deployed to meet a given stormwater retention target?• How well will LID controls perform under future meteorological projections made by global climate change models?• What are the relativ

  13. Physically based modelling of rainfall-runoff processes

    NARCIS (Netherlands)

    Diermanse, F.L.M.

    2001-01-01

    This PhD. research was set up to investigate the use of rainfall-runoff models for simulation of high water events in hillslope areas. First, dominant parameters for runoff production during high water events have been identified. Subsequently, the influence of antecedent conditions on runoff percen

  14. Causes of toxicity to Hyalella azteca in a stormwater management facility receiving highway runoff and snowmelt. Part II: salts, nutrients, and water quality.

    Science.gov (United States)

    Bartlett, A J; Rochfort, Q; Brown, L R; Marsalek, J

    2012-01-01

    The Terraview-Willowfield Stormwater Management Facility (TWSMF) features a tandem of stormwater management ponds, which receive inputs of multiple contaminants from highway and residential runoff. Previous research determined that benthic communities in the ponds were impacted by poor habitat quality, due to elevated sediment concentrations of metals and polycyclic aromatic hydrocarbons (PAHS), and salinity in the overlying water, but did not address seasonal changes, including those caused by the influx of contaminants with the snowmelt. In order to address this issue, water and sediment samples were collected from the TWSMF during the fall and spring, and four-week sediment toxicity tests were conducted with Hyalella azteca. The effects of metals and PAHs are discussed in a companion paper; the effects of road salt, nutrients, and water quality are discussed here. After exposure to fall samples, survival of Hyalella was reduced (64-74% of controls) at three out of four sites, but growth was not negatively affected. After exposure to spring samples, survival was 0-75% of controls at the two sites furthest downstream, and growth was significantly lower in four out of five sites when comparing Hyalella exposed to site water overlying site sediment versus control water overlying site sediment. Toxicity appeared to be related to chloride concentrations: little or no toxicity occurred in fall samples (200 mg Cl(-)/L), and significant effects on survival and growth occurred in spring samples above 1550 mg Cl(-)/L and 380 mg Cl(-)/L, respectively. Sodium chloride toxicity tests showed similar results: four-week LC50s and EC25s (growth) were 1200 and 420 mg Cl(-)/L, respectively. Although water quality and nutrients were associated with effects observed in the TWSMF, chloride from road salt was the primary cause of toxicity in this study. Chloride persists during much of the year at concentrations representing a significant threat to benthic communities in the TWSMF.

  15. Developing a stochastic conflict resolution model for urban runoff quality management: Application of info-gap and bargaining theories

    Science.gov (United States)

    Ghodsi, Seyed Hamed; Kerachian, Reza; Estalaki, Siamak Malakpour; Nikoo, Mohammad Reza; Zahmatkesh, Zahra

    2016-02-01

    In this paper, two deterministic and stochastic multilateral, multi-issue, non-cooperative bargaining methodologies are proposed for urban runoff quality management. In the proposed methodologies, a calibrated Storm Water Management Model (SWMM) is used to simulate stormwater runoff quantity and quality for different urban stormwater runoff management scenarios, which have been defined considering several Low Impact Development (LID) techniques. In the deterministic methodology, the best management scenario, representing location and area of LID controls, is identified using the bargaining model. In the stochastic methodology, uncertainties of some key parameters of SWMM are analyzed using the info-gap theory. For each water quality management scenario, robustness and opportuneness criteria are determined based on utility functions of different stakeholders. Then, to find the best solution, the bargaining model is performed considering a combination of robustness and opportuneness criteria for each scenario based on utility function of each stakeholder. The results of applying the proposed methodology in the Velenjak urban watershed located in the northeastern part of Tehran, the capital city of Iran, illustrate its practical utility for conflict resolution in urban water quantity and quality management. It is shown that the solution obtained using the deterministic model cannot outperform the result of the stochastic model considering the robustness and opportuneness criteria. Therefore, it can be concluded that the stochastic model, which incorporates the main uncertainties, could provide more reliable results.

  16. Integrated treatment and recycling of stormwater: a review of Australian practice.

    Science.gov (United States)

    Hatt, Belinda E; Deletic, Ana; Fletcher, Tim D

    2006-04-01

    With the use of water approaching, and in some cases exceeding, the limits of sustainability in many locations, there is an increasing recognition of the need to utilise stormwater for non-potable requirements, thus reducing the demand on potable sources. This paper presents a review of Australian stormwater treatment and recycling practices as well as a discussion of key lessons and identified knowledge gaps. Where possible, recommendations for overcoming these knowledge gaps are given. The review of existing stormwater recycling systems focussed primarily on the recycling of general urban runoff (runoff generated from all urban surfaces) for non-potable purposes. Regulations and guidelines specific to stormwater recycling need to be developed to facilitate effective design of such systems, and to minimise risks of failure. There is a clear need for the development of innovative techniques for the collection, treatment and storage of stormwater. Existing stormwater recycling practice is far ahead of research, in that there are no technologies designed specifically for stormwater recycling. Instead, technologies designed for general stormwater pollution control are frequently utilised, which do not guarantee the necessary reliability of treatment. Performance modelling for evaluation purposes also needs further research, so that industry can objectively assess alternative approaches. Just as many aspects of these issues may have impeded adoption of stormwater, another impediment to adoption has been the lack of a practical and widely accepted method for assessing the many financial, social and ecological costs and benefits of stormwater recycling projects against traditional alternatives. Such triple-bottom-line assessment methodologies need to be trialled on stormwater recycling projects. If the costs and benefits of recycling systems can be shown to compare favourably with the costs and benefits of conventional practices this will provide an incentive to overcome

  17. Stormwater Management Plan for the Arden Hills Army Training Site, Arden Hills, Minnesota

    Energy Technology Data Exchange (ETDEWEB)

    Carr, Adrianne E. [Argonne National Lab. (ANL), Argonne, IL (United States); Wuthrich, Kelsey K. [Argonne National Lab. (ANL), Argonne, IL (United States); Ziech, Angela M. [Argonne National Lab. (ANL), Argonne, IL (United States); Bowen, Esther E. [Argonne National Lab. (ANL), Argonne, IL (United States); Quinn, John [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-03-01

    This stormwater management plan focuses on the cantonment and training areas of the Arden Hills Army Training Site (AHATS). The plan relates the site stormwater to the regulatory framework, and it summarizes best management practices to aide site managers in promoting clean site runoff. It includes documentation for a newly developed, detailed model of stormwater flow retention for the entire AHATS property and adjacent upgradient areas. The model relies on established modeling codes integrated in a U.S. Department of Defense-sponsored software tool, the Watershed Modeling System (WMS), and it can be updated with data on changes in land use or with monitoring data.

  18. Experimental analysis and modeling of a stormwater perlite filter.

    Science.gov (United States)

    Gironás, Jorge; Adriasola, José M; Fernández, Bonifacio

    2008-06-01

    This paper presents the study of a mixed porous media composed of expanded perlite and a nonwoven needle-punched geotextile used to reduce the suspended solids load and concentration in urban runoff. Laboratory procedures were designed to quantify the suspended solids removal efficiency and variation in time of filtration rate. Different grain-size distributions of expanded perlite, diverse suspended solids concentrations, and different hydraulic and geometric conditions were tested to determine the most effective filter media. A dimensionless parameter, termed Global Performance Index (GPI), was developed to reach this objective. Measured data were also used to build a dimensional and a regression model to represent the performance of the filter media mathematically. The theory, derivation, and performance of both models are presented and compared with an existent empirical model. The dimensional model better reproduces the observations, becoming a useful tool for the design, operation, and evaluation of commercial porous media filters.

  19. Source-Flux-Fate Modelling of Priority Pollutants in Stormwater Systems

    DEFF Research Database (Denmark)

    Vezzaro, Luca

    the significant level of uncertainty affecting stormwater quality models, the identification of sources of uncertainty (based on Global Sensitivity Analysis - GSA) and quantification of model prediction bounds (based on pseudo-Bayesian methods, such as the Generalized Likelihood Uncertainty Estimation - GLUE......) are presented as crucial elements in modelling of stormwater PP. Special focus is on assessing the use of combined informal likelihood measures assigning equal weights at different model outputs (flow and quality measurements). Management of the spatially heterogeneous sources of stormwater PP requires...... a detailed catchment characterization, based on land use and the use of information stored in Geographical Information System (GIS). The analysis carried out in the thesis, which compares different characterization approaches with different level of detail, suggests in fact that this approach allows...

  20. MARKET INCENTIVES AND NONPOINT SOURCES: AN APPLICATION OF TRADABLE CREDITS TO URBAN STORMWATER MANAGEMENT

    Science.gov (United States)

    Excess stormwater runoff can cause serious pollution, habitat degradation and flooding in cities where growth in impervious surface area (such as pavement, buildings, etc.) has created a situation where stormwater runoff routinely exceeds the normal capacity of natural and constr...

  1. MARKET INCENTIVES AND NONPOINT SOURCES: AN APPLICATION OF TRADABLE CREDITS TO URBAN STORMWATER MANAGEMENT

    Science.gov (United States)

    Excess stormwater runoff can cause serious pollution, habitat degradation and flooding in cities where growth in impervious surface area (such as pavement, buildings, etc.) has created a situation where stormwater runoff routinely exceeds the normal capacity of natural and constr...

  2. Causes of toxicity to Hyalella azteca in a stormwater management facility receiving highway runoff and snowmelt. Part I: polycyclic aromatic hydrocarbons and metals.

    Science.gov (United States)

    Bartlett, A J; Rochfort, Q; Brown, L R; Marsalek, J

    2012-01-01

    The Terraview-Willowfield Stormwater Management Facility (TWSMF) receives inputs of multiple contaminants, including metals, polycyclic aromatic hydrocarbons (PAHs), road salt, and nutrients, via highway and residential runoff. Contaminant concentrations in runoff are seasonally dependent, and are typically high in early spring, coinciding with the snowmelt. In order to investigate the seasonal fluctuations of contaminant loading and related changes in toxicity to benthic invertebrates, overlying water and sediment samples were collected in the fall and spring, reflecting low and high contaminant loading, respectively, and four-week sediment toxicity tests were conducted with Hyalella azteca. The effects of metals and PAHs are discussed here; the effects of salts, nutrients, and water quality are discussed in a companion paper. Survival and growth of Hyalella after exposure to fall samples were variable: survival was significantly reduced (64-74% of controls) at three out of four sites, but there were no significant growth effects. More dramatic effects were observed after Hyalella were exposed to spring samples: survival was significantly reduced at the two sites furthest downstream (0-75% of controls), and growth was significantly lower in four out of five sites when comparing Hyalella exposed to site sediment with overlying site water versus site sediment with overlying control water. These seasonal changes in toxicity were not related to metals or PAHs: 1. levels of bioavailable metals were below those expected to cause toxicity, and 2. levels of PAHs in sediment were lowest at sites with the greatest toxicity and highest in water and sediment at sites with no toxicity. Although not associated with toxicity, some metals and PAHs exceeded probable and severe effect levels, and could be a cause for concern if contaminant bioavailability changes. Toxicity in the TWSMF appeared to be primarily associated with water-borne contaminants. The cause(s) of these effects

  3. Stormwater infiltration and the 'urban karst' - A review

    Science.gov (United States)

    Bonneau, Jeremie; Fletcher, Tim D.; Costelloe, Justin F.; Burns, Matthew J.

    2017-09-01

    The covering of native soils with impervious surfaces (e.g. roofs, roads, and pavement) prevents infiltration of rainfall into the ground, resulting in increased surface runoff and decreased groundwater recharge. When this excess water is managed using stormwater drainage systems, flow and water quality regimes of urban streams are severely altered, leading to the degradation of their ecosystems. Urban streams restoration requires alternative approaches towards stormwater management, which aim to restore the flow regime towards pre-development conditions. The practice of stormwater infiltration-achieved using a range of stormwater source-control measures (SCMs)-is central to restoring baseflow. Despite this, little is known about what happens to the infiltrated water. Current knowledge about the impact of stormwater infiltration on flow regimes was reviewed. Infiltration systems were found to be efficient at attenuating high-flow hydrology (reducing peak magnitudes and frequencies) at a range of scales (parcel, streetscape, catchment). Several modelling studies predict a positive impact of stormwater infiltration on baseflow, and empirical evidence is emerging, but the fate of infiltrated stormwater remains unclear. It is not known how infiltrated water travels along the subsurface pathways that characterise the urban environment, in particular the 'urban karst', which results from networks of human-made subsurface pathways, e.g. stormwater and sanitary sewer pipes and associated high permeability trenches. Seepage of groundwater into and around such pipes is possible, meaning some infiltrated stormwater could travel along artificial pathways. The catchment-scale ability of infiltration systems to restore groundwater recharge and baseflow is thus ambiguous. Further understanding of the fate of infiltrated stormwater is required to ensure infiltration systems deliver optimal outcomes for waterway flow regimes.

  4. Uncertainties of stormwater characteristics and removal rates of stormwater treatment facilities: implications for stormwater handling.

    Science.gov (United States)

    Langeveld, J G; Liefting, H J; Boogaard, F C

    2012-12-15

    Stormwater runoff is a major contributor to the pollution of receiving waters. This study focuses at characterising stormwater in order to be able to determine the impact of stormwater on receiving waters and to be able to select the most appropriate stormwater handling strategy. The stormwater characterisation is based on determining site mean concentrations (SMCs) and their uncertainties as well as the treatability of stormwater by monitoring specific pollutants concentration levels (TSS, COD, BOD, TKN, TP, Pb, Cu, Zn, E.coli) at three full scale stormwater treatment facilities in Arnhem, the Netherlands. This has resulted in 106 storm events being monitored at the lamella settler, 59 at the high rate sand filter and 132 at the soil filter during the 2 year monitoring period. The stormwater characteristics in Arnhem in terms of SMCs for main pollutants TSS and COD and settling velocities differ from international data. This implies that decisions for stormwater handling made on international literature data will very likely be wrong due to assuming too high concentrations of pollutants and misjudgement of the treatability of stormwater. The removal rates monitored at the full scale treatment facilities are within the expected range, with the soil filter and the sand filter having higher removal rates than the lamella settler. The full scale pilots revealed the importance of incorporating gross solids removal in the design of stormwater treatment facilities, as the gross solids determine operation and maintenance requirements.

  5. Tailoring Green Infrastructure Implementation Scenarios based on Stormwater Management Objectives

    Science.gov (United States)

    Green infrastructure (GI) refers to stormwater management practices that mimic nature by soaking up, storing, and controlling onsite. GI practices can contribute reckonable benefits towards meeting stormwater management objectives, such as runoff peak shaving, volume reduction, f...

  6. Modeling the Performance of Sand Filters for Removing Runoff Suspended Sediment

    Science.gov (United States)

    2013-11-01

    release; distribution is unlimited. Prepared for US Army Corps of Engineers Washington, DC 20314-1000 ERDC/EL CR-13-3 ii Abstract Geotextile tubes...sediments in urban stormwater runoff, and thus should be effective in removing metals in runoff from SAFRs. Porous geotextile fabric is used to hold...public release; unlimited distribution. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Geotextile tubes filled with sand are being evaluated for filter

  7. Method for assessment of stormwater treatment facilities – Synthetic road runoff addition including micro-pollutants and tracer

    DEFF Research Database (Denmark)

    Cederkvist, Karin; Jensen, Marina Bergen; Holm, Peter Engelund

    2017-01-01

    representative of runoff from roads is suggested, as well as relevant concentration ranges. The method was used for adding contaminants to three different STFs including a curbstone extension with filter soil, a dual porosity filter, and six different permeable pavements. Evaluation of the method showed......% in the dual porosity filter, stressing the importance of including a conservative tracer for correction of contaminant retention values. The method is considered useful in future treatment performance testing of STFs. The observed performance of the STFs is presented in coming papers....

  8. Progress on the improvement of urban stormwater runoff quality by bioretention%生物滞留池改善城市雨水径流水质的研究进展

    Institute of Scientific and Technical Information of China (English)

    胡爱兵; 张书函; 陈建刚

    2011-01-01

    Proper and effective control of the non-point source pollution causing by stormwater runoff has become a major challenge for many urban managers. Bioretention as one of the best management practices (BMPs) of urban stormwater could be employed for effective control the non-point source pollution. This paper summarizes the research progress of bioretention for improving urban stormwater runoff quality, and presents the associated pollutant removal mechanisms simultanly. The literature data of select field and lab studies have demonstrated that bioretention is effective for removing TSS, heavy metals, oil & grease and pathogenic bacteria from stormwater runoff, while its nutrient removal effectiveness is not stable depending on the variable local factors such as the soil composition and plant type. Finally, promising research directions of bioretention for improving stormwater runoff quality are predicted.%如何有效控制城市雨水径流所带来的面源污染已成为城市管理工作所面临的重要难题之一.作为城市暴雨最佳管理措施(BMPs)中的技术之一,生物滞留池可有效控制城市面源污染.总结了生物滞留池在改善城市雨水径流水质方面的研究进展,简要分析了生物滞留池去除污染物的机制.研究结果表明,生物滞留池对雨水径流中的总悬浮颗粒物(TSS)、重金属、油脂类及致病菌等污染物有较好的去除效果,而对N、P等营养物质的去除效果不稳定.最后,对生物滞留池改善城市雨水径流水质进一步的研究方向进行了展望.

  9. Evaluating Escherichia coli removal performance in stormwater biofilters: a preliminary modelling approach.

    Science.gov (United States)

    Chandrasena, G I; Deletic, A; McCarthy, D T

    2013-01-01

    Stormwater biofilters are not currently optimised for pathogen removal since the behaviour of these pollutants within the stormwater biofilters is poorly understood. Modelling is a common way of optimising these systems, which also provides a better understanding of the major processes that govern the pathogen removal. This paper provides an overview of a laboratory-scale study that investigated how different design and operational conditions impact pathogen removal in the stormwater biofilters. These data were then used to develop a modelling tool that can be used to optimise the design and operation of the stormwater biofilters. The model uses continuous simulations where adsorption and desorption were dominant during wet weather periods and first order die-off kinetics were significant in dry periods between the wet weather events. Relatively high Nash Sutcliffe Efficiencies (>0.5) indicate that the calibrated model is in good agreement with observed data and the optimised model parameters were comparable with values reported in the literature. The model's sensitivity is highest towards the adsorption process parameter followed by the die-off and desorption rate parameters, which implies that adsorption is the governing process of the model. Vegetation is found to have an impact on the wet weather processes since the adsorption and desorption parameters vary significantly with the different plant configurations. The model is yet to be tested against field data and needs to be improved to represent the effect of some other biofilter design configurations, such as the inclusion of the submerged zone.

  10. Mapping Stormwater Retention in the Cities: A Flexible Model for Data-Scarce Environments

    Science.gov (United States)

    Hamel, P.; Keeler, B.

    2014-12-01

    There is a growing demand for understanding and mapping urban hydrological ecosystem services, including stormwater retention for flood mitigation and water quality improvement. Progress in integrated urban water management and low impact development in Western countries increased our understanding of how grey and green infrastructure interact to enhance these services. However, valuation methods that account for a diverse group of beneficiaries are typically not made explicit in urban water management models. In addition, the lack of spatial data on the stormwater network in developing countries makes it challenging to apply state-of-the-art models needed to understand both the magnitude and spatial distribution of the stormwater retention service. To fill this gap, we designed the Urban InVEST stormwater retention model, a tool that complements the suite of InVEST software models to quantify and map ecosystem services. We present the model structure emphasizing the data requirements from a user's perspective and the representation of services and beneficiaries. We illustrate the model application with two case studies in a data-rich (New York City) and data-scarce environment. We discuss the difference in the level of information obtained when less resources (data, time, or expertise) are available, and how this affects multiple ecosystem service assessments that the tool is ultimately designed for.

  11. Comparing flow duration curve and rainfall-runoff modelling for predicting daily runoff in ungauged catchments

    Science.gov (United States)

    Zhang, Yongqiang; Vaze, Jai; Chiew, Francis H. S.; Li, Ming

    2015-06-01

    Predicting daily runoff time series in ungauged catchments is both important and challenging. For the last few decades, the rainfall-runoff (RR) modelling approach has been the method of choice. There have been very few studies reported in literature which attempt to use flow duration curve (FDC) to predict daily runoff time series. This study comprehensively compares the two approaches using an extensive dataset (228 catchments) for a large region of south-eastern Australia and provides guidelines for choosing the suitable method. For each approach we used the nearest neighbour method and two weightings - a 5-donor simple mathematical average (SA) and a 5-donor inverse-distance weighting (5-IDW) - to predict daily runoff time series. The results show that 5-IDW was noticeably better than a single donor to predict daily runoff time series, especially for the FDC approach. The RR modelling approach calibrated against daily runoff outperformed the FDC approach for predicting high flows. The FDC approach was better at predicting medium to low flows in traditional calibration against the Nash-Sutcliffe-Efficiency or Root Mean Square Error, but when calibrated against a low flow objective function, both the FDC and rainfall-runoff models performed equally well in simulating the low flows. These results indicate that both methods can be further improved to simulate daily hydrographs describing the range of flow metrics in ungauged catchments. Further studies should be carried out for improving the accuracy of predicted FDC in ungauged catchments, including improving the FDC model structure and parameter fitting.

  12. Developing an ecosystem model of a floating wetland for water quality improvement on a stormwater pond.

    Science.gov (United States)

    McAndrew, Brendan; Ahn, Changwoo

    2017-11-01

    An ecosystem model was developed to assist with designing and implementing a floating wetland (FW) for water quality management of urban stormwater ponds, focusing on nitrogen (N) removal. The model is comprised of three linked submodels: hydrology, plant growth, and nitrogen. The model was calibrated with the data that resulted from a FW constructed and implemented as part of an interdisciplinary pedagogical project on a university campus, titled "The Rain Project", which raised awareness of stormwater issues while investigating the potential application of green infrastructure for sustainable stormwater management. The FW had been deployed during the summer of 2015 (i.e., May through mid-September) on a major stormwater pond located at the center of the Fairfax Campus of George Mason University near Washington, D.C. We used the model to explore the impact of three design elements of FW (i.e., hydraulic residence time (HRT), surface area coverage, and primary productivity) on the function of FW. Model simulations showed enhanced N removal performance as HRT and surface area coverage increased. The relatively low macrophyte productivity observed indicates that, in the case of our pond and FW, N removal was very limited. The model results suggest that even full pond surface coverage would result in meager N removal (∼6%) at a HRT of one week. A FW with higher plant productivity, more representative of that reported in the literature, would require only 10% coverage to achieve similar N removal efficiency (∼7%). Therefore, macrophyte productivity appears to have a greater impact on FW performance on N removal than surface area coverage or pond HRT. The outcome of the study shows that this model, though limited in scope, may be useful in aiding the design of FW to augment the performance of degraded stormwater ponds in an effort to meet local water quality goals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Highway-runoff quality, and treatment efficiencies of a hydrodynamic-settling device and a stormwater-filtration device in Milwaukee, Wisconsin

    Science.gov (United States)

    Horwatich, Judy A.; Bannerman, Roger T.; Pearson, Robert

    2011-01-01

    The treatment efficiencies of two prefabricated stormwater-treatment devices were tested at a freeway site in a high-density urban part of Milwaukee, Wisconsin. One treatment device is categorized as a hydrodynamic-settling device (HSD), which removes pollutants by sedimentation and flotation. The other treatment device is categorized as a stormwater-filtration device (SFD), which removes pollutants by filtration and sedimentation. During runoff events, flow measurements were recorded and water-quality samples were collected at the inlet and outlet of each device. Efficiency-ratio and summation-of-load (SOL) calculations were used to estimate the treatment efficiency of each device. Event-mean concentrations and loads that were decreased by passing through the HSD include total suspended solids (TSS), suspended sediment (SS), total phosphorus (TP), total copper (TCu), and total zinc (TZn). The efficiency ratios for these constituents were 42, 57, 17, 33, and 23 percent, respectively. The SOL removal rates for these constituents were 25, 49, 10, 27, and 16 percent, respectively. Event-mean concentrations and loads that increased by passing through the HSD include chloride (Cl), total dissolved solids (TDS), and dissolved zinc (DZn). The efficiency ratios for these constituents were -347, -177, and 20 percent, respectively. Four constituents—dissolved phosphorus (DP), chemical oxygen demand (COD), total polycyclic aromatic hydrocarbon (PAH), and dissolved copper (DCu)—are not included in the list of computed efficiency ratio and SOL because the variability between sampled inlet and outlet pairs were not significantly different. Event-mean concentrations and loads that decreased by passing through the SFD include TSS, SS, TP, DCu, TCu, DZn, TZn, and COD. The efficiency ratios for these constituents were 59, 90, 40, 21, 66, 23, 66, and 18, respectively. The SOLs for these constituents were 50, 89, 37, 19, 60, 20, 65, and 21, respectively. Two constituents—DP and

  14. Hillslope soil erosion and runoff model for natural rainfall events

    Institute of Scientific and Technical Information of China (English)

    Zhanyu Zhang; Guohua Zhang; Changqing Zuo; Xiaoyu Pi

    2008-01-01

    By using the momentum theorem and water balance principle, basic equations of slope runoff were derived, soil erosion by raindrop splash and runoff were discussed and a model was established for decribing hillslope soil erosion processes. The numerical solution of the model was obtained by adopting the Preissmann format and considering the common solution-determining conditions, from which not only the runoff and soil erosion but also their processes can be described. The model was validated by ten groups of observation data of Soil Conservation Ecological Science and Technology Demonstration Park of Jiangxi Province. Comparisons show that the maximum relative error between simulation and experimental data is about 10.98% for total runoff and 15% for total erosion, 5.2% for runoff process and 6.1% for erosion process, indicating that the model is conceptually realistic and reliable and offers a feasible approach for further studies on the soil erosion process.

  15. MODELING OF STORM WATER RUNOFF FROM GREEN ROOFS

    Directory of Open Access Journals (Sweden)

    Ewa Burszta-Adamiak

    2014-10-01

    Full Text Available Apart from direct measurements, modelling of runoff from green roofs is valuable source of information about effectiveness of this type of structure from hydrological point of view. Among different type of models, the most frequently used are numerical models. They allow to assess the impact of green roofs on decrease and attenuation of runoff, reduction of peak runoff and value of water retention. This paper presents preliminary results of research on computing the rate of runoff from green roofs using GARDENIA model. The analysis has been carried out for selected rainfall events registered during measuring campaign on pilot-scale green roofs. Obtained results are promising and show good fit between observed and simulated runoff.

  16. From runoff to rainfall: inverse rainfall–runoff modelling in a high temporal resolution

    Directory of Open Access Journals (Sweden)

    M. Herrnegger

    2014-12-01

    Full Text Available This paper presents a novel technique to calculate mean areal rainfall in a high temporal resolution of 60 min on the basis of an inverse conceptual rainfall–runoff model and runoff observations. Rainfall exhibits a large spatio-temporal variability, especially in complex alpine terrain. Additionally, the density of the monitoring network in mountainous regions is low and measurements are subjected to major errors, which lead to significant uncertainties in areal rainfall estimates. The most reliable hydrological information available refers to runoff, which in the presented work is used as input for a rainfall–runoff model. Thereby a conceptual, HBV-type model is embedded in an iteration algorithm. For every time step a rainfall value is determined, which results in a simulated runoff value that corresponds to the observation. To verify the existence, uniqueness and stability of the inverse rainfall, numerical experiments with synthetic hydrographs as inputs into the inverse model are carried out successfully. The application of the inverse model with runoff observations as driving input is performed for the Krems catchment (38.4 km2, situated in the northern Austrian Alpine foothills. Compared to station observations in the proximity of the catchment, the inverse rainfall sums and time series have a similar goodness of fit, as the independent INCA rainfall analysis of Austrian Central Institute for Meteorology and Geodynamics (ZAMG. Compared to observations, the inverse rainfall estimates show larger rainfall intensities. Numerical experiments show, that cold state conditions in the inverse model do not influence the inverse rainfall estimates, when considering an adequate spin-up time. The application of the inverse model is a feasible approach to obtain improved estimates of mean areal rainfall. These can be used to enhance interpolated rainfall fields, e.g. for the estimation of rainfall correction factors, the parameterisation of

  17. Modeling tropical river runoff:A time dependent approach

    Institute of Scientific and Technical Information of China (English)

    Rashmi Nigam; Sudhir Nigam; Sushil K.Mittal

    2014-01-01

    Forecasting of rainfall and subsequent river runoff is important for many operational problems and applications related to hydrol-ogy. Modeling river runoff often requires rigorous mathematical analysis of vast historical data to arrive at reasonable conclusions. In this paper we have applied the stochastic method to characterize and predict river runoff of the perennial Kulfo River in south-ern Ethiopia. The time series analysis based auto regressive integrated moving average (ARIMA) approach is applied to mean monthly runoff data with 10 and 20 years spans. The varying length of the input runoff data is shown to influence the forecasting efficiency of the stochastic process. Preprocessing of the runoff time series data indicated that the data do not follow a seasonal pattern. Our forecasts were made using parsimonious non seasonal ARIMA models and the results were compared to actual 10-year and 20-year mean monthly runoff data of the Kulfo River. Our results indicate that river runoff forecasts based upon the 10-year data are more accurate and efficient than the model based on the 20-year time series.

  18. RAINFALL-RUNOFF MODELING IN THE TURKEY RIVER USING ...

    African Journals Online (AJOL)

    2015-01-15

    Jan 15, 2015 ... Modeling rainfall-runoff relationships in a watershed have an important role in water .... Initial estimations will improve following the development of the model. .... Resources Research Nordic Hydrology, 33 (5), 2002,33 1-346.

  19. Runoff erosion

    OpenAIRE

    Evelpidou, Niki; Cordier, Stephane; Merino, Agustin (Ed.); Figueiredo, Tomás; Centeri, Csaba

    2013-01-01

    Table of Contents PART I – THEORY OF RUNOFF EROSION CHAPTER 1 - RUNOFF EROSION – THE MECHANISMS CHAPTER 2 - LARGE SCALE APPROACHES OF RUNOFF EROSION CHAPTER 3 - MEASURING PRESENT RUNOFF EROSION CHAPTER 4 - MODELLING RUNOFF EROSION CHAPTER 5 - RUNOFF EROSION AND HUMAN SOCIETIES: THE INFLUENCE OF LAND USE AND MANAGEMENT PRACTICES ON SOIL EROSION PART II - CASE STUDIES CASE STUDIES – INTRODUCTION: RUNOFF EROSION IN MEDITERRANEAN AREA CASE STUDY 1: Soil Erosion Risk...

  20. Stormwater biofilter treatment model (MPiRe) for selected micro-pollutants.

    Science.gov (United States)

    Randelovic, Anja; Zhang, Kefeng; Jacimovic, Nenad; McCarthy, David; Deletic, Ana

    2016-02-01

    Biofiltration systems, also known as bioretentions or rain-gardens, are widely used for treatment of stormwater. In order to design them well, it is important to improve models that can predict their performance. This paper presents a rare model that can simulate removal of a wide range of micro-pollutants from stormwater by biofilters. The model is based on (1) a bucket approach for water flow simulation, and (2) advection/dispersion transport equations for pollutant transport and fate. The latter includes chemical non-equilibrium two-site model of sorption, first-order decay, and volatilization, thus is a compromise between the limited availability of data (on stormwater micro-pollutants) and the required complexity to accurately describe the nature of the phenomenon. The model was calibrated and independently validated on two field data series collected for different organic micro-pollutants at two biofilters of different design. This included data on triazines (atrazine, prometryn, and simazine), glyphosate, and chloroform during six simulated stormwater events. The data included variable and challenging biofilter operational conditions; e.g. variable inflow volumes, dry and wet period dynamics, and inflow pollutant concentrations. The model was able to simulate water flow well, with slight discrepancies being observed only during long dry periods when, presumably, soil cracking occurred. In general, the agreement between simulated and measured pollutographs was good. As with flows, the long dry periods posed a problem for water quality simulation (e.g. simazine and prometryn were difficult to model in low inflow events that followed prolonged dry periods). However, it was encouraging that pollutant transport and fate parameters estimated by the model calibration were in agreement with available literature data. This suggests that the model could probably be adopted for assessment of biofilter performance of other stormwater micro-pollutants (PAHs, phenols

  1. Runoff Simulation of Shitoukoumen Reservoir Basin Based on SWAT Model

    Institute of Scientific and Technical Information of China (English)

    XIE; Miao; LI; Hong-yan; LIU; Tie-juan; RU; Shi-rong

    2012-01-01

    [Objective]The study aimed to simulate the runoff of Shitoukoumen Reservoir basin by using SWAT model. [Method] Based on DEM elevation, land use type, soil type and hydrometeorological data, SWAT model, a distributed hydrological model was established to simulate the monthly runoff of Shitoukoumen Reservoir basin, and the years 2006 and 2010 were chosen as the calibration and validation period respectively. [Result] The simulation results indicated that SWAT model could be used to simulate the runoff of Shitoukoumen Reservoir basin, and the simulation effect was good. However, the response of the model to local rainstorm was not obvious, so that the actual runoff in June and July of 2010 was abnormally higher than the simulation value. [Conclusion] The research could provide theoretical references for the plan and management of water resources in Shitoukoumen Reservoir basin in future.

  2. Modelling surface run-off and trends analysis over India

    Science.gov (United States)

    Gupta, P. K.; Chauhan, S.; Oza, M. P.

    2016-08-01

    The present study is mainly concerned with detecting the trend of run-off over the mainland of India, during a time period of 35 years, from 1971-2005 (May-October). Rainfall, soil texture, land cover types, slope, etc., were processed and run-off modelling was done using the Natural Resources Conservation Service (NRCS) model with modifications and cell size of 5×5 km. The slope and antecedent moisture corrections were incorporated in the existing model. Trend analysis of estimated run-off was done by taking into account different analysis windows such as cell, medium and major river basins, meteorological sub-divisions and elevation zones across India. It was estimated that out of the average 1012.5 mm of rainfall over India (considering the study period of 35 years), 33.8% got converted to surface run-off. An exponential model was developed between the rainfall and the run-off that predicted the run-off with an R 2 of 0.97 and RMSE of 8.31 mm. The run-off trend analysed using the Mann-Kendall test revealed that a significant pattern exists in 22 medium, two major river basins and three meteorological sub-divisions, while there was no evidence of a statistically significant trend in the elevation zones. Among the medium river basins, the highest positive rate of change in the run-off was observed in the Kameng basin (13.6 mm/yr), while the highest negative trend was observed in the Tista upstream basin (-21.4 mm/yr). Changes in run-off provide valuable information for understanding the region's sensitivity to climatic variability.

  3. Modelling surface run-off and trends analysis over India

    Indian Academy of Sciences (India)

    P K Gupta; S Chauhan; M P Oza

    2016-08-01

    The present study is mainly concerned with detecting the trend of run-off over the mainland of India, during a time period of 35 years, from 1971–2005 May–October). Rainfall, soil texture, land cover types, slope, etc., were processed and run-off modelling was done using the Natural Resources ConservationService (NRCS) model with modifications and cell size of 5×5 km. The slope and antecedent moisture corrections were incorporated in the existing model. Trend analysis of estimated run-off was done by taking into account different analysis windows such as cell, medium and major river basins, meteorologicalsub-divisions and elevation zones across India. It was estimated that out of the average 1012.5 mm of rainfall over India (considering the study period of 35 years), 33.8% got converted to surface run-off. An exponential model was developed between the rainfall and the run-off that predicted the run-off with an $R^2$ of 0.97 and RMSE of 8.31 mm. The run-off trend analysed using the Mann–Kendall test revealed that a significant pattern exists in 22 medium, two major river basins and three meteorological subdivisions, while there was no evidence of a statistically significant trend in the elevation zones. Among the medium river basins, the highest positive rate of change in the run-off was observed in the Kameng basin (13.6 mm/yr), while the highest negative trend was observed in the Tista upstream basin (−21.4 mm/yr). Changes in run-off provide valuable information for understanding the region’s sensitivity to climatic variability.

  4. Runoff modeling of the Mara River using Satellite Observed Soil ...

    African Journals Online (AJOL)

    with European Remote Sensing (ERS) Scatterometer in modeling runoff of the Zambezi river basin. ... (2008) using Geospatial Stream Flow ... obtained for Mara River at Mara mines, Nyangores at Bomet and Amala at Mulot river gauging ...

  5. Modeling Rainfall-Runoff Response to Land Use and Land Cover Change in Rwanda (1990–2016

    Directory of Open Access Journals (Sweden)

    Fidele Karamage

    2017-02-01

    Full Text Available Stormwater runoff poses serious environmental problems and public health issues in Rwanda, a tropical country that is increasingly suffering from severe floods, landslides, soil erosion and water pollution. Using the WetSpa Extension model, this study assessed the changes in rainfall runoff depth in Rwanda from 1990 to 2016 in response to precipitation and land use changes. Our results show that Rwanda has experienced a significant conversion of natural forest and grassland to cropland and built-up areas. During the period 1990–2016, 7090.02 km2 (64.5% and 1715.26 km2 (32.1% of forest and grassland covers were lost, respectively, while the cropland and built-up areas increased by 135.3% (8503.75 km2 and 304.3% (355.02 km2, respectively. According to our estimates, the land use change effect resulted in a national mean runoff depth increase of 2.33 mm/year (0.38%. Although precipitation change affected the inter-annual fluctuation of runoff, the long-term trend of runoff was dominated by land use change. The top five districts that experienced the annual runoff depth increase (all >3.8 mm/year are Rubavu, Nyabihu, Ngororero, Gakenke, and Musanze. Their annual runoff depths increased at a rate of >3.8 mm/year during the past 27 years, due to severe deforestation (ranging from 62% to 85% and cropland expansion (ranging from 123% to 293%. These areas require high priority in runoff control using terracing in croplands and rainwater harvesting systems such as dam/reservoirs, percolation tanks, storage tanks, etc. The wet season runoff was three times higher than the dry season runoff in Rwanda; appropriate rainwater management and reservation could provide valuable irrigation water for the dry season or drought years (late rainfall onsets or early rainfall cessations. It was estimated that a reservation of 30.5% (3.99 km3 of the runoff in the wet season could meet the cropland irrigation water gap during the dry season in 2016.

  6. How does imperviousness develop and affect runoff generation in an urbanizing watershed?

    Directory of Open Access Journals (Sweden)

    Gerald Krebs

    2013-08-01

    Full Text Available Imperviousness associated with urbanization remains one of the biggest challenges in sustainable urban design. The replacement of forests, marshlands, buffers, and wetlands with impervious surfaces, strongly influences hydrological processes in urbanizing areas. This study analyzed the contribution of four constructed surfaces types – roofs, yards, roads, and an international airport – to surface runoff within a 21 km2 watershed, and presents the development over five decades (1977−2030. The land-cover model, used to assess watershed imperviousness in 2030, utilized coefficients between impervious areas generating surface runoff and the floor area, developed during the study. The conducted imperviousness analysis allowed the evaluation of land-use development impacts on the stream network, and the identification of hydrologically active areas for urban planning and stormwater management. Research revealed the importance of yard imperviousness related to suburban residential housing for stormwater runoff generation, and the impacts of transport-related imperviousness on stormwater runoff.

  7. EPA RESEARCH IN URBAN STORMWATER POLLUTION CONTROL

    Science.gov (United States)

    This state-of-the-art on the Environmental Protection Agency' s research in urban stormwater and combined sewer overflow pollution control describes the major elements of the Urban Runoff Pollution Control Program. roblem definition, users assistance tools, management alternative...

  8. EPA RESEARCH IN URBAN STORMWATER POLLUTION CONTROL

    Science.gov (United States)

    This state-of-the-art on the Environmental Protection Agency' s research in urban stormwater and combined sewer overflow pollution control describes the major elements of the Urban Runoff Pollution Control Program. roblem definition, users assistance tools, management alternative...

  9. 强化渗蓄土壤改良实验研究%Study of Soil Improvement to Enhance Stormwater Runoff Infiltration

    Institute of Scientific and Technical Information of China (English)

    刘强; 王建龙; 李俊奇

    2012-01-01

    Because of soil's poor penetrability in some cities of China,rainfall runoff is difficult to infiltrate and have retention.Two soil conditioners were manufactured: CSZ,which constituted by comstalk and zeolite;and CTS,which constituted by turf and sand.Through small-scale study,the soil conditioners' permeability amendment effect and runoff purification effect on heavy clay soil were detected.The results showed that: the soil reformed by CSZ,the stable infiltration rate range is from 2×10-5 m/s~8×10-5 m/s,the permeability is increased by about 1 130~5 030 times than the original soil,pollutant removal rate of the soil which ameliorated by CSZ for COD,TP,NH3-N,TN are 6%~25%,30%~56%,27%~49%,and 18%~33% respectively;the soil reformed by CTS,the stable infiltration rate range from 2×10-6 m/s~2×10-5 m/s,the permeability increased by about 90~1 160 times than the original soil,removal rate of COD,TP,NH3-N,TN are 88%~94%,91%~99%,91%~93% and 6%~54%.Therefore,CSZ is suitable for the soil improvement which takes water quantity control as the goal,and CTS is suitable for the soil improvement which takes water quality control as goal.The results can provide scientific support for the urban stormwater runoff's infiltration promoting and drainage reducing,rainwater utilization,waterlogging controll and green space's planning and designing in the heavy clay soil regions.%针对我国部分城市土壤渗透性能差、不利于径流雨水渗蓄减排等情况,分别以秸秆和沸石制成CSZ改良剂(conditioner of comstalk and zeolite),以泥炭和石英砂制成CTS改良剂(conditioner of turf and quartz sand),研究了上述两种改良剂对黏重土壤渗透性能改良和径流雨水水质净化效果的影响.结果表明:CSZ改良后的土壤稳定渗透速率为2×10-5~8×10-5m/s,渗透性能提高1 130~5 030倍,对COD的去除率为6%~25%,TP为30%~56%,NH3-N为27%~49%,TN为18%~33%;CTS改良后土壤稳定渗透速率为2×10-6~2

  10. Modeling of the Monthly Rainfall-Runoff Process Through Regressions

    Directory of Open Access Journals (Sweden)

    Campos-Aranda Daniel Francisco

    2014-10-01

    Full Text Available To solve the problems associated with the assessment of water resources of a river, the modeling of the rainfall-runoff process (RRP allows the deduction of runoff missing data and to extend its record, since generally the information available on precipitation is larger. It also enables the estimation of inputs to reservoirs, when their building led to the suppression of the gauging station. The simplest mathematical model that can be set for the RRP is the linear regression or curve on a monthly basis. Such a model is described in detail and is calibrated with the simultaneous record of monthly rainfall and runoff in Ballesmi hydrometric station, which covers 35 years. Since the runoff of this station has an important contribution from the spring discharge, the record is corrected first by removing that contribution. In order to do this a procedure was developed based either on the monthly average regional runoff coefficients or on nearby and similar watershed; in this case the Tancuilín gauging station was used. Both stations belong to the Partial Hydrologic Region No. 26 (Lower Rio Panuco and are located within the state of San Luis Potosi, México. The study performed indicates that the monthly regression model, due to its conceptual approach, faithfully reproduces monthly average runoff volumes and achieves an excellent approximation in relation to the dispersion, proved by calculation of the means and standard deviations.

  11. Estimating degree day factors from MODIS for snowmelt runoff modeling

    Directory of Open Access Journals (Sweden)

    Z. H. He

    2014-07-01

    Full Text Available Degree-day factors are widely used to estimate snowmelt runoff in operational hydrological models. Usually, they are calibrated on observed runoff, and sometimes on satellite snow cover data. In this paper, we propose a new method for estimating the snowmelt degree-day factor (DDFS directly from MODIS snow covered area (SCA and ground based snow depth data without calibration. Subcatchment snow volume is estimated by combining SCA and snow depths. Snow density is estimated as the ratio of observed precipitation and changes in the snow volume for days with snow accumulation. Finally, DDFS values are estimated as the ratio of changes in the snow water equivalent and degree-day temperatures for days with snow melt. We compare simulations of basin runoff and snow cover patterns using spatially variable DDFS estimated from snow data with those using spatially uniform DDFS calibrated on runoff. The runoff performances using estimated DDFS are slightly improved, and the simulated snow cover patterns are significantly more plausible. The new method may help reduce some of the runoff model parameter uncertainty by reducing the total number of calibration parameters.

  12. 模拟生物滞留池净化城市机动车道路雨水径流%Simulated Bioretention Pond for Improving Quality of Stormwater Runoff on Urban Traffic Road

    Institute of Scientific and Technical Information of China (English)

    胡爱兵; 李子富; 张书函; 陈建刚

    2012-01-01

    The rapid development of the urbanization experienced in China has led to large volume and poor quality of stormwater runoff on traffic roads. A laboratory bioretention soil column study was conducted to investigate the performance of bioretention pond for improving the quality of stormwater runoff on traffic roads. The aim of the study was to choose a reliable medium in the bioretention pond. In the nature filling state, when the nutrient content in media in bioretention pond was 5% to 10% (the content of loamy sand was 30% to 25% , and that of sand was 65% ) , NH3-N, TN, TP, COD and SS in traffic road runoff could be removed effectively.%我国城市化的快速发展致使城市机动车道路雨水径流量显著增大,雨水水质明显恶化.采用土柱模拟生物滞留池,考察了其对城市机动车道路雨水径流水质的改善效果,以确定适宜的生物滞留池填料构成.结果表明,在自然装填状态下,生物滞留池种植土壤填料中营养土的含量为5% ~10%(相应壤质土的含量为30% ~25%,砂的含量为65%)时,对雨水径流中氨氮、TN、TP、COD和SS的去除效果较好.

  13. Comparative Analysis of Uncertainties in Urban Surface Runoff Modelling

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Schaarup-Jensen, Kjeld

    2007-01-01

    In the present paper a comparison between three different surface runoff models, in the numerical urban drainage tool MOUSE, is conducted. Analysing parameter uncertainty, it is shown that the models are very sensitive with regards to the choice of hydrological parameters, when combined overflow...... analysis, further research in improved parameter assessment for surface runoff models is needed....... volumes are compared - especially when the models are uncalibrated. The occurrences of flooding and surcharge are highly dependent on both hydrological and hydrodynamic parameters. Thus, the conclusion of the paper is that if the use of model simulations is to be a reliable tool for drainage system...

  14. Evaluation of Rainfall-Runoff Models for Mediterranean Subcatchments

    Science.gov (United States)

    Cilek, A.; Berberoglu, S.; Donmez, C.

    2016-06-01

    The development and the application of rainfall-runoff models have been a corner-stone of hydrological research for many decades. The amount of rainfall and its intensity and variability control the generation of runoff and the erosional processes operating at different scales. These interactions can be greatly variable in Mediterranean catchments with marked hydrological fluctuations. The aim of the study was to evaluate the performance of rainfall-runoff model, for rainfall-runoff simulation in a Mediterranean subcatchment. The Pan-European Soil Erosion Risk Assessment (PESERA), a simplified hydrological process-based approach, was used in this study to combine hydrological surface runoff factors. In total 128 input layers derived from data set includes; climate, topography, land use, crop type, planting date, and soil characteristics, are required to run the model. Initial ground cover was estimated from the Landsat ETM data provided by ESA. This hydrological model was evaluated in terms of their performance in Goksu River Watershed, Turkey. It is located at the Central Eastern Mediterranean Basin of Turkey. The area is approximately 2000 km2. The landscape is dominated by bare ground, agricultural and forests. The average annual rainfall is 636.4mm. This study has a significant importance to evaluate different model performances in a complex Mediterranean basin. The results provided comprehensive insight including advantages and limitations of modelling approaches in the Mediterranean environment.

  15. EVALUATION OF RAINFALL-RUNOFF MODELS FOR MEDITERRANEAN SUBCATCHMENTS

    Directory of Open Access Journals (Sweden)

    A. Cilek

    2016-06-01

    Full Text Available The development and the application of rainfall-runoff models have been a corner-stone of hydrological research for many decades. The amount of rainfall and its intensity and variability control the generation of runoff and the erosional processes operating at different scales. These interactions can be greatly variable in Mediterranean catchments with marked hydrological fluctuations. The aim of the study was to evaluate the performance of rainfall-runoff model, for rainfall-runoff simulation in a Mediterranean subcatchment. The Pan-European Soil Erosion Risk Assessment (PESERA, a simplified hydrological process-based approach, was used in this study to combine hydrological surface runoff factors. In total 128 input layers derived from data set includes; climate, topography, land use, crop type, planting date, and soil characteristics, are required to run the model. Initial ground cover was estimated from the Landsat ETM data provided by ESA. This hydrological model was evaluated in terms of their performance in Goksu River Watershed, Turkey. It is located at the Central Eastern Mediterranean Basin of Turkey. The area is approximately 2000 km2. The landscape is dominated by bare ground, agricultural and forests. The average annual rainfall is 636.4mm. This study has a significant importance to evaluate different model performances in a complex Mediterranean basin. The results provided comprehensive insight including advantages and limitations of modelling approaches in the Mediterranean environment.

  16. Simulation of the hydraulic performance of highway filter drains through laboratory models and stormwater management tools.

    Science.gov (United States)

    Sañudo-Fontaneda, Luis A; Jato-Espino, Daniel; Lashford, Craig; Coupe, Stephen J

    2017-05-23

    Road drainage is one of the most relevant assets in transport infrastructure due to its inherent influence on traffic management and road safety. Highway filter drains (HFDs), also known as "French Drains", are the main drainage system currently in use in the UK, throughout 7000 km of its strategic road network. Despite being a widespread technique across the whole country, little research has been completed on their design considerations and their subsequent impact on their hydraulic performance, representing a gap in the field. Laboratory experiments have been proven to be a reliable indicator for the simulation of the hydraulic performance of stormwater best management practices (BMPs). In addition to this, stormwater management tools (SMT) have been preferentially chosen as a design tool for BMPs by practitioners from all over the world. In this context, this research aims to investigate the hydraulic performance of HFDs by comparing the results from laboratory simulation and two widely used SMT such as the US EPA's stormwater management model (SWMM) and MicroDrainage®. Statistical analyses were applied to a series of rainfall scenarios simulated, showing a high level of accuracy between the results obtained in laboratory and using SMT as indicated by the high and low values of the Nash-Sutcliffe and R (2) coefficients and root-mean-square error (RMSE) reached, which validated the usefulness of SMT to determine the hydraulic performance of HFDs.

  17. Fuzzy committees of specialised rainfall-runoff models: further enhancements

    NARCIS (Netherlands)

    Kayastha, N.; Ye, J.; Fenicia, F.; Solomatine, D.P.

    2013-01-01

    Often a single hydrological model cannot capture the details of a complex rainfall-runoff relationship, and a possibility here is building specialised models to be responsible for a particular aspect of this relationship and combining them forming a committee model. This study extends earlier work o

  18. PERFORMANCE OF STORMWATER RETENTION PONDS AND CONSTRUCTED WETLANDS IN REDUCING MICROBIAL CONCENTRATIONS

    Science.gov (United States)

    Stormwater runoff can transport high concentrations of pathogens to receiving waters. Bacteria indicator organisms, as surrogates for pathogens, are the most often reported cause of receiving water impairments. Stormwater best management practices (BMPs) are often considered effe...

  19. Modelling runoff from a Himalayan debris-covered glacier

    Directory of Open Access Journals (Sweden)

    K. Fujita

    2014-02-01

    Full Text Available Although the processes by which glacial debris-mantles alter the melting of glacier ice have been well studied, the mass balance and runoff patterns of Himalayan debris-covered glaciers and the response of these factors to climate change are not well understood. Many previous studies have addressed mechanisms of ice melt under debris mantles by applying multiplicative parameters derived from field experiments, and other studies have calculated the details of heat conduction through the debris layer. However, those approaches cannot be applied at catchment scales because debris distributions are heterogeneous and difficult to measure. Here, we establish a runoff model for a Himalayan debris-covered glacier in which the spatial distribution of the thermal properties of the debris mantle is estimated from remotely sensed multi-temporal data. We validated the model for the Tsho Rolpa Glacial Lake–Trambau Glacier basin in the Nepal Himalaya, using hydro-meteorological observations obtained for a 3.5 yr period (1993–1996. We calculated long-term averages of runoff components for the period 1980–2007 using gridded reanalysis datasets. Our calculations suggest that excess meltwater from the debris-covered area contributes significantly to the total runoff, mainly because of its location at lower elevations. Uncertainties in runoff values due to estimations of the thermal properties and albedo of the debris-covered surface were assessed to be approximately 8% of the runoff from the debris-covered area. We evaluated the sensitivities of runoff components to changes in air temperature and precipitation. As expected, warmer air temperatures increase the total runoff by increasing the melting rate; however, increased precipitation slightly reduces the total runoff, as ice melting is suppressed by the increased snow cover and associated high albedo. The response of total runoff to changing precipitation is complex because of the different responses of

  20. Discharge Water Quality Models of Storm Runoff in a Catchment

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The relationships between the water qualities of nitrogen and phosphorous contents in the discharge water and the discharge of storm runoff of an experimental catchment including terraced paddy field are analyzed based on experiment results of the catchment. By summarizing the currently related research on water quality models, the water quality models of different components of storm runoff of the catchment are presented and verified with the experiment data of water quality analyses and the corresponding discharge of the storm runoffs during 3 storms. Through estimating the specific discharge of storm runoff, the specific load of different components of nitrogen and phosphorus in the discharge water of the catchment can be forecasted by the models. It is found that the mathematical methods of linear regression are very useful for analysis of the relationship between the concentrations of nitrogen and phosphorus and the water discharge of storm runoff. It is also found that the most content of the nitrogen (75%) in the discharge water is organic, while half of the content (49%) of phosphorus in the discharge water is inorganic.

  1. National Stormwater Calculator: Low Impact Development Stormwater Control Cost Estimation Programming & Future Enhancements - Presentation

    Science.gov (United States)

    The National Stormwater Calculator (NSC) makes it easy to estimate runoff reduction when planning a new development or redevelopment site with low impact development (LID) stormwater controls. The Calculator is currently deployed as a Windows desktop application. The NSC is organ...

  2. Model-based comparison of strategies for reduction of stormwater micropollutant emissions

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Sharma, Anitha Kumari; Mikkelsen, Peter Steen

    to improve the recipient quality by reducing the fluxes of heavy metals (copper, zinc) and organic compounds (fluoranthene) to natural waters. MP sources were identified by using GIS land usage data. When comparing the different control strategies, the integrated model showed the greater benefits...... of the source-control strategy in terms of MP loads discharged in the environment and sediment accumulated in the pond. None of the simulated pollution control strategies managed to fulfil water quality criteria based on Emission Limit Values. This study highlights the great contribution that integrated models...... can provide to the management of stormwater pollution....

  3. Supporting data for “A glacier runoff extension to the precipitation runoff modeling system”

    Science.gov (United States)

    Van Beusekom, Ashley; Viger, Roland

    2017-01-01

    This product is an archive of the modeling artifacts used to produce a journal paper (Van Beusekom and Viger, 2016). The abstract for that paper follows. A module to simulate glacier runoff, PRMSglacier, was added to PRMS (Precipitation Runoff Modeling System), a distributed-parameter, physical-process hydrological simulation code. The extension does not require extensive on-glacier measurements or computational expense but still relies on physical principles over empirical relations as much as is feasible while maintaining model usability. PRMSglacier is validated on two basins in Alaska, Wolverine, and Gulkana Glacier basin, which have been studied since 1966 and have a substantial amount of data with which to test model performance over a long period of time covering a wide range of climatic and hydrologic conditions. When error in field measurements is considered, the Nash-Sutcliffe efficiencies of streamflow are 0.87 and 0.86, the absolute bias fractions of the winter mass balance simulations are 0.10 and 0.08, and the absolute bias fractions of the summer mass balances are 0.01 and 0.03, all computed over 42 years for the Wolverine and Gulkana Glacier basins, respectively. Without taking into account measurement error, the values are still within the range achieved by the more computationally expensive codes tested over shorter time periods.

  4. Towards a generic rainfall-runoff model for green roofs.

    Science.gov (United States)

    Kasmin, H; Stovin, V R; Hathway, E A

    2010-01-01

    A simple conceptual model for green roof hydrological processes is shown to reproduce monitored data, both during a storm event, and over a longer continuous simulation period. The model comprises a substrate moisture storage component and a transient storage component. Storage within the substrate represents the roof's overall stormwater retention capacity (or initial losses). Following a storm event the retention capacity is restored by evapotranspiration (ET). However, standard methods for quantifying ET do not exist. Monthly ET values are identified using four different approaches: analysis of storm event antecedent dry weather period and initial losses data; calibration of the ET parameter in a continuous simulation model; use of the Thornthwaite ET formula; and direct laboratory measurement of evaporation. There appears to be potential to adapt the Thornthwaite ET formula to provide monthly ET estimates from local temperature data. The development of a standardized laboratory test for ET will enable differences resulting from substrate characteristics to be quantified.

  5. Study on effects of storm-water detention facilities in an urbanized watershed using a distributed model

    OpenAIRE

    賈, 仰文; 倪, 广恒; 木内, 豪; 吉谷, 純一; 河原, 能久; 末次, 忠司

    2001-01-01

    A distributed hydrological model - WEP (Water and Energy transfer Process) model is improved at first by adding overland flow and storm-water detention pond's components, as well as changing the kinematic wave method into the dynamic wave method for the flow routing of main rivers to consider tidal effects. The modified model is then utilized to evaluate the effects of storm-water detention ponds and infiltration trenches in the Ebi river watershed with a grid size of 50m and a time step of 1...

  6. Runoff forecasting by artificial neural network and conventional model

    Directory of Open Access Journals (Sweden)

    A.R. Ghumman

    2011-12-01

    Full Text Available Rainfall runoff models are highly useful for water resources planning and development. In the present study rainfall–runoff model based on Artificial Neural Networks (ANNs was developed and applied on a watershed in Pakistan. The model was developed to suite the conditions in which the collected dataset is short and the quality of dataset is questionable. The results of ANN models were compared with a mathematical conceptual model. The cross validation approach was adopted for the generalization of ANN models. The precipitation used data was collected from Meteorological Department Karachi Pakistan. The results confirmed that ANN model is an important alternative to conceptual models and it can be used when the range of collected dataset is short and data is of low standard.

  7. Surface clogging process modeling of suspended solids during urban stormwater aquifer recharge

    Institute of Scientific and Technical Information of China (English)

    Zijia Wang; Xinqiang Du; Yuesuo Yang; Xueyan Ye

    2012-01-01

    Aquifer recharge,which uses urban stormwater,is an effective technique to control the negative effects of groundwater overexploitation,while clogging problems in infiltration systems remain the key restricting factor in broadening its practice.Quantitative understanding of the clogging process is still very poor.A laboratory study was conducted to understand surface physical clogging processes,with the primary aim of developing a model for predicting suspended solid clogging processes before aquifer recharge projects start.The experiments investigated the clogging characteristics of different suspended solid sizes in recharge water by using a series of one-dimensional fine quartz sand columns.The results showed that the smaller the suspended particles in recharge water,the farther the distance of movement and the larger the scope of clogging in porous media.Clogging extents in fine sand were 1 cm,for suspended particle size ranging from 0.075 to 0.0385 mm,and 2 cm,for particles less than 0.0385 mm.In addition,clogging development occurred more rapidly for smaller suspended solid particles.It took 48,42,and 36 hr respectively,for large-,medium-,and small-sized particles to reach pre-determined clogging standards.An empirical formula and iteration model for the surface clogging evolution process were derived.The verification results obtained from stormwater recharge into fine sand demonstrated that the model could reflect the real laws of the surface clogging process.

  8. Legacies in Urban Stormwater Management: A Case Study of a Gully Network in Northern Delaware

    Science.gov (United States)

    Wehner, C. E.; Claessens, L.; Santangelo, T.; Soroka, A.

    2013-12-01

    Increased stormwater runoff from urban surfaces could lead to erosion and gully formation in areas of steep topographic relief. To reduce these impacts, stormwater management practices are currently required through federal and state stormwater regulations. Before 1990, stormwater was not regulated and would often be directly routed into adjacent lands. Particularly in areas of steep terrain, this would potentially induce erosion and gully formation. This study reports on a wide-scale examination of gully formation from urban stormwater, using a model that examines the increase of runoff from impervious cover and the potential for gully formation. Here we report on a case study for an area on the University of Delaware campus. The area is located in the Piedmont region and drains into the White Clay Creek, a National Wild and Scenic River. Pre-regulation development in this area has led to the formation of a series of gullies with distinct morphological characteristics. This study examines in detail the reach-scale and contributing area controls on gully formation. We conducted a GIS analysis of the local hydrologic network, determined peak flow of each gully, developed a gully susceptibility model that we compared with the site characteristics, and sampled the sediment concentrations of the gully flow during storm events. We also characterized historical land use data and performed field observations for our analysis. We found that the development changed the hydrology of the site, altering the contributing areas of each gully. In addition, field observations revealed distinct rates of incision across gullies as well as along different sections of each gully. We also found that the gullies are still actively eroding, contributing large sediment loads to the downstream White Clay Creek. Our research provides a better understanding of the local and regional factors governing erosion and gully formation. The model that we created will help to identify sites that

  9. Storm Water Management Model (SWMM)

    Science.gov (United States)

    EPA's Storm Water Management Model (SWMM) is used throughout the world for planning, analysis and design related to stormwater runoff, combined and sanitary sewers, and other drainage systems in urban areas.

  10. Monitoring, chemical fate modelling and uncertainty assessment in combination: a tool for evaluating emission control scenarios for micropollutants in stormwater systems

    DEFF Research Database (Denmark)

    Mikkelsen, Peter Steen; Vezzaro, Luca; Birch, Heidi

    2012-01-01

    Stormwater discharges can represent significant sources of micropollutants (MP), including heavy metals and xenobiotic organic compounds that may pose a toxicity risk to aquatic ecosystems. Control of stormwater quality and reduction of MP loads is therefore necessary for a sustainable stormwater...... management in urban areas, but it is strongly hampered by the general lack of field data on these substances. A framework for combining field monitoring campaigns with dynamic MP modelling tools and statistical methods for uncertainty analysis was hence developed to estimate MP fluxes and fate in stormwater...... on land usage allowed characterizing the catchment and identifying the major potential sources of stormwater MP. Monitoring of the pond inlet and outlet, as well as sediment analyses, allowed assessing the current situation and highlighted potential risks for the downstream surface water environment...

  11. Selection of an appropriately simple storm runoff model

    Directory of Open Access Journals (Sweden)

    A. I. J. M. van Dijk

    2009-09-01

    Full Text Available Alternative conceptual storm runoff models, including several published ones, were evaluated against storm flow time series for 260 catchments in Australia (23–1902 km2. The original daily streamflow data was separated into baseflow and storm flow components and from these, event rainfall and storm flow totals were estimated. For each tested model structure, the number of free parameters was reduced in stages. The appropriate balance between simplicity and explanatory power was decided based on Aikake's Final Prediction Error Criterion and evidence of parameter equivalence. The majority of catchments showed storm recession half-times in the order of a day, with more rapid drainage in dry catchments. Overland and channel travel time did not appear to be an important driver of storm flow recession. A storm runoff model with two free parameters (one related to storm event size, the other to antecedent baseflow and a fixed initial loss of 12 mm provided the optimal model structure. The optimal model had some features similar to the Soil Conservation Service Curve Number technique, but performed an average 12 to 19% better. The non-linear relationship between event rainfall and event runoff may be associated with saturated area expansion during storms and/or the relationship between storm event size and peak rainfall intensity. Antecedent baseflow was a strong predictor of runoff response. A simple conceptual relationship between groundwater storage and saturated catchment area proved adequate and produced realistic estimates of saturated area of <0.1% for the driest and >5% for the wettest catchments.

  12. Random Modeling of Daily Rainfall and Runoff Using a Seasonal Model and Wavelet Denoising

    Directory of Open Access Journals (Sweden)

    Chien-ming Chou

    2014-01-01

    Full Text Available Instead of Fourier smoothing, this study applied wavelet denoising to acquire the smooth seasonal mean and corresponding perturbation term from daily rainfall and runoff data in traditional seasonal models, which use seasonal means for hydrological time series forecasting. The denoised rainfall and runoff time series data were regarded as the smooth seasonal mean. The probability distribution of the percentage coefficients can be obtained from calibrated daily rainfall and runoff data. For validated daily rainfall and runoff data, percentage coefficients were randomly generated according to the probability distribution and the law of linear proportion. Multiplying the generated percentage coefficient by the smooth seasonal mean resulted in the corresponding perturbation term. Random modeling of daily rainfall and runoff can be obtained by adding the perturbation term to the smooth seasonal mean. To verify the accuracy of the proposed method, daily rainfall and runoff data for the Wu-Tu watershed were analyzed. The analytical results demonstrate that wavelet denoising enhances the precision of daily rainfall and runoff modeling of the seasonal model. In addition, the wavelet denoising technique proposed in this study can obtain the smooth seasonal mean of rainfall and runoff processes and is suitable for modeling actual daily rainfall and runoff processes.

  13. A simplified model of pathogenic pollution for managing beaches ...

    African Journals Online (AJOL)

    A simplified model of pathogenic pollution for managing beaches. ... key physical processes involved in mixing and dispersion of pathogenic pollution at ... Key words: beach-water quality model, pathogenic pollution, storm-water runoff, E. coli

  14. Quantity and quality of stormwater collected from selected stormwater outfalls at industrial sites, Fort Gordon, Georgia, 2012

    Science.gov (United States)

    Nagle, Doug D.

    2013-01-01

    An assessment of the quantity and quality of stormwater runoff associated with industrial activities at Fort Gordon was conducted from January through August 2012. The assessment was provided to satisfy the requirements from a general permit that authorizes the discharge of stormwater under the National Pollutant Discharge Elimination System from a site associated with industrial activities. The stormwater quantity refers to the runoff discharge at the point and time of the runoff sampling. The study was conducted by the U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon.

  15. Regionalized rainfall-runoff model to estimate low flow indices

    Science.gov (United States)

    Garcia, Florine; Folton, Nathalie; Oudin, Ludovic

    2016-04-01

    Estimating low flow indices is of paramount importance to manage water resources and risk assessments. These indices are derived from river discharges which are measured at gauged stations. However, the lack of observations at ungauged sites bring the necessity of developing methods to estimate these low flow indices from observed discharges in neighboring catchments and from catchment characteristics. Different estimation methods exist. Regression or geostatistical methods performed on the low flow indices are the most common types of methods. Another less common method consists in regionalizing rainfall-runoff model parameters, from catchment characteristics or by spatial proximity, to estimate low flow indices from simulated hydrographs. Irstea developed GR2M-LoiEau, a conceptual monthly rainfall-runoff model, combined with a regionalized model of snow storage and melt. GR2M-LoiEau relies on only two parameters, which are regionalized and mapped throughout France. This model allows to cartography monthly reference low flow indices. The inputs data come from SAFRAN, the distributed mesoscale atmospheric analysis system, which provides daily solid and liquid precipitation and temperature data from everywhere in the French territory. To exploit fully these data and to estimate daily low flow indices, a new version of GR-LoiEau has been developed at a daily time step. The aim of this work is to develop and regionalize a GR-LoiEau model that can provide any daily, monthly or annual estimations of low flow indices, yet keeping only a few parameters, which is a major advantage to regionalize them. This work includes two parts. On the one hand, a daily conceptual rainfall-runoff model is developed with only three parameters in order to simulate daily and monthly low flow indices, mean annual runoff and seasonality. On the other hand, different regionalization methods, based on spatial proximity and similarity, are tested to estimate the model parameters and to simulate

  16. Surface clogging process modeling of suspended solid during urban stormwater aquifer recharge

    Science.gov (United States)

    Wang, Z.

    2012-04-01

    Aquifer recharge (AR), which uses urban stormwater, is an effective technique to control the negative environmental effects of groundwater over-exploitation. While AR is widely used worldwide, clogging problems in infiltration systems remain the key restricting factor in broadening its practice. At present, quantitative understanding of the clogging process is still very poor. A laboratory study was conducted to understand surface physical clogging processes, with the primary aim of developing a model for predicting suspended solid clogging process before the AR projects start. The experiments investigated the clogging characteristics of different suspended solids size in recharge water by using a series of 1-D fine quartz sand columns. The results showed that the smaller the suspended particles in recharge water, the farther the distance of movement and the larger the scope of clogging in porous media. Clogging extents in fine sand were 1 cm, with suspended particle sizes ranging from 0.075 mm to 0.0385 mm, and 2 cm, with particles less than 0.0385 mm. In addition, clogging development occurred faster for smaller suspended solid particles. It took large-, medium-, and small-sized particles 48, 42, and 36 h, respectively, to reach pre-determined clogging standards. An empirical formula and its recursive model for the surface clogging evolution process were derived based on the series of experiments. The verification results obtained by stormwater recharge into the fine sand demonstrated that the model could reflect the real conditions of surface clogging processes. Parameter sensitivity of the model was determined, and results showed that the estimated parameters in model would not cause obvious errors for clogging prediction.

  17. An analogue conceptual rainfall-runoff model for educational purposes

    Science.gov (United States)

    Herrnegger, Mathew; Riedl, Michael; Schulz, Karsten

    2016-04-01

    Conceptual rainfall-runoff models, in which runoff processes are modelled with a series of connected linear and non-linear reservoirs, remain widely applied tools in science and practice. Additionally, the concept is appreciated in teaching due to its somewhat simplicity in explaining and exploring hydrological processes of catchments. However, when a series of reservoirs are used, the model system becomes highly parametrized and complex and the traceability of the model results becomes more difficult to explain to an audience not accustomed to numerical modelling. Since normally the simulations are performed with a not visible digital code, the results are also not easily comprehensible. This contribution therefore presents a liquid analogue model, in which a conceptual rainfall-runoff model is reproduced by a physical model. This consists of different acrylic glass containers representing different storage components within a catchment, e.g. soil water or groundwater storage. The containers are equipped and connected with pipes, in which water movement represents different flow processes, e.g. surface runoff, percolation or base flow. Water from a storage container is pumped to the upper part of the model and represents effective rainfall input. The water then flows by gravity through the different pipes and storages. Valves are used for controlling the flows within the analogue model, comparable to the parameterization procedure in numerical models. Additionally, an inexpensive microcontroller-based board and sensors are used to measure storage water levels, with online visualization of the states as time series data, building a bridge between the analogue and digital world. The ability to physically witness the different flows and water levels in the storages makes the analogue model attractive to the audience. Hands-on experiments can be performed with students, in which different scenarios or catchment types can be simulated, not only with the analogue but

  18. Comparison of different uncertainty techniques in urban stormwater quantity and quality modelling

    DEFF Research Database (Denmark)

    Dotto, C. B.; Mannina, G.; Kleidorfer, M.

    2012-01-01

    is the assessment and comparison of different techniques generally used in the uncertainty assessment of the parameters of water models. This paper compares a number of these techniques: the Generalized Likelihood Uncertainty Estimation (GLUE), the Shuffled Complex Evolution Metropolis algorithm (SCEM......-UA), an approach based on a multi-objective auto-calibration (a multialgorithm, genetically adaptive multiobjective method, AMALGAM) and a Bayesian approach based on a simplified Markov Chain Monte Carlo method (implemented in the software MICA). To allow a meaningful comparison among the different uncertainty...... techniques, common criteria have been set for the likelihood formulation, defining the number of simulations, and the measure of uncertainty bounds. Moreover, all the uncertainty techniques were implemented for the same case study, in which the same stormwater quantity and quality model was used alongside...

  19. Experimental Study on Infiltrating Stormwater Runoff with Rain Garden in Xi'an,China%西安市雨水花园蓄渗雨水径流的试验研究

    Institute of Scientific and Technical Information of China (English)

    唐双成; 罗纨; 贾忠华; 袁黄春

    2012-01-01

    雨水花园是结合城市景观,以滞留和净化雨水径流为主要功能的生物滞留处理系统,能够在一定程度上减轻城市化进程对城市水文和水质的负面影响。根据在西安市雨水花园蓄渗屋面雨水径流的现场试验,确定在各种暴雨条件下,花园设计及土壤入渗能力不同时,雨水花园拦蓄雨水径流的能力以及花园溢流的时间和溢流量。结果显示,黄土具有良好的入渗能力,达到2.346m/d;在较为湿润的2011年基本没有发生溢流,汇集的雨水径流全部入渗补给了地下水。对于某一重现期的暴雨,雨水花园溢流总量受到降雨强度和历时二者叠加效果的影响。%Rain gardens are bioretention systems that are designed with urban landscaping and used for retaining and purifying urban stormwater runoff.Rain gardens can mitigate the adverse impact of urbanization on hydrology and water quality.This paper presented an experimental study on the infiltration capability of a rain garden constructed in Xi'an,China.Time and volume for overflow in the rain garden under storms of variable duration and recurrence interval were calculated.The results showed that the loess soil in Xi'an area had a good infiltration capacity,the average value of the measured infiltration rates was 2.346 m/d in the rain garden,nearly all stormwater runoff collected in the relatively wet year of 2011 infiltrated and recharged to the groundwater.For storms of a specified recurrence interval,rainfall intensity and the duration were two controlling factors that caused overflow in the rain garden.

  20. Snowmelt runoff modeling: Limitations and potential for mitigating water disputes

    Science.gov (United States)

    Kult, Jonathan; Choi, Woonsup; Keuser, Anke

    2012-04-01

    SummaryConceptual snowmelt runoff models have proven useful for estimating discharge from remote mountain basins including those spanning the various ranges of the Himalaya. Such models can provide water resource managers with fairly accurate predictions of water availability for operational purposes (e.g. irrigation and hydropower). However, these models have limited ability to address characteristic components of water disputes such as diversions, storage and withholding. Contemporary disputes between India and Pakistan surrounding the snowmelt-derived water resources of the Upper Indus Basin highlight the need for improved water balance accounting methods. We present a research agenda focused on providing refined hydrological contributions to water dispute mitigation efforts.

  1. Towards a comprehensive physically-based rainfall-runoff model

    Directory of Open Access Journals (Sweden)

    Z. Liu

    2002-01-01

    Full Text Available This paper introduces TOPKAPI (TOPographic Kinematic APproximation and Integration, a new physically-based distributed rainfall-runoff model deriving from the integration in space of the kinematic wave model. The TOPKAPI approach transforms the rainfall-runoff and runoff routing processes into three ‘structurally-similar’ non-linear reservoir differential equations describing different hydrological and hydraulic processes. The geometry of the catchment is described by a lattice of cells over which the equations are integrated to lead to a cascade of non-linear reservoirs. The parameter values of the TOPKAPI model are shown to be scale independent and obtainable from digital elevation maps, soil maps and vegetation or land use maps in terms of slope, soil permeability, roughness and topology. It can be shown, under simplifying assumptions, that the non-linear reservoirs aggregate into three reservoir cascades at the basin scale representing the soil, the surface and the drainage network, following the topographic and geomorphologic elements of the catchment, with parameter values which can be estimated directly from the small scale ones. The main advantage of this approach lies in its capability of being applied at increasing spatial scales without losing model and parameter physical interpretation. The model is foreseen to be suitable for land-use and climate change impact assessment; for extreme flood analysis, given the possibility of its extension to ungauged catchments; and last but not least as a promising tool for use with General Circulation Models (GCMs. To demonstrate the quality of the comprehensive distributed/lumped TOPKAPI approach, this paper presents a case study application to the Upper Reno river basin with an area of 1051 km2 based on a DEM grid scale of 200 m. In addition, a real-world case of applying the TOPKAPI model to the Arno river basin, with an area of 8135 km2 and using a DEM grid scale of 1000 m, for the

  2. Urban Stormwater Governance: The Need for a Paradigm Shift

    Science.gov (United States)

    Dhakal, Krishna P.; Chevalier, Lizette R.

    2016-05-01

    Traditional urban stormwater management involves rapid removal of stormwater through centralized conveyance systems of curb-gutter-pipe networks. This results in many adverse impacts on the environment including hydrological disruption, groundwater depletion, downstream flooding, receiving water quality degradation, channel erosion, and stream ecosystem damage. In order to mitigate these adverse impacts, urban stormwater managers are increasingly using green infrastructure that promote on-site infiltration, restore hydrological functions of the landscape, and reduce surface runoff. Existing stormwater governance, however, is centralized and structured to support the conventional systems. This governance approach is not suited to the emerging distributed management approach, which involves multiple stakeholders including parcel owners, government agencies, and non-governmental organizations. This incongruence between technology and governance calls for a paradigm shift in the governance from centralized and technocratic to distributed and participatory governance. This paper evaluates how five US cities have been adjusting their governance to address the discord. Finally, the paper proposes an alternative governance model, which provides a mechanism to involve stakeholders and implement distributed green infrastructure under an integrative framework.

  3. High-rate stormwater clarification with polymeric flocculant addition.

    Science.gov (United States)

    Wood, J; He, C; Rochfort, Q; Marsalek, J; Seto, P; Yang, M; Chessie, P; Kok, S

    2005-01-01

    Treatment of urban stormwater by clarification, with flocculant addition, was studied in Toronto, Canada using a pilot-scale clarifier with removable lamellar plates. Almost 90 stormwater runoff events were characterised at the study site and found fairly polluted. The previous research phase indicated good treatability of this stormwater by lamellar clarification with flocculant addition (total suspended solids, TSS, removal of 84%, at a surface load of 15 m/h), but there were concerns about cleaning plates after storm events. With the aid of numerical modelling, hydraulic improvements to the clarifier inlet zone were retrofitted in 2004 and permitted the removal of the lamellar pack without a loss in treatment efficiency. In the modified clarifier, a cationic polymeric flocculant dosage of 4 mg/L with conventional clarification provided a TSS removal of 77%, at surface loads up to 43 m/h. The use of the polymer did not increase the acute toxicity of the treated effluent. The clarifier sludge was severely polluted by several heavy metals and would require special disposal. The treatment process tested could be well applied in projects requiring intensive stormwater treatment at compact sites.

  4. Urban Stormwater Governance: The Need for a Paradigm Shift.

    Science.gov (United States)

    Dhakal, Krishna P; Chevalier, Lizette R

    2016-05-01

    Traditional urban stormwater management involves rapid removal of stormwater through centralized conveyance systems of curb-gutter-pipe networks. This results in many adverse impacts on the environment including hydrological disruption, groundwater depletion, downstream flooding, receiving water quality degradation, channel erosion, and stream ecosystem damage. In order to mitigate these adverse impacts, urban stormwater managers are increasingly using green infrastructure that promote on-site infiltration, restore hydrological functions of the landscape, and reduce surface runoff. Existing stormwater governance, however, is centralized and structured to support the conventional systems. This governance approach is not suited to the emerging distributed management approach, which involves multiple stakeholders including parcel owners, government agencies, and non-governmental organizations. This incongruence between technology and governance calls for a paradigm shift in the governance from centralized and technocratic to distributed and participatory governance. This paper evaluates how five US cities have been adjusting their governance to address the discord. Finally, the paper proposes an alternative governance model, which provides a mechanism to involve stakeholders and implement distributed green infrastructure under an integrative framework.

  5. A model library for dynamic transport and fate of micropollutants in integrated urban wastewater and stormwater systems

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Benedetti, Lorenzo; Gevaert, Veerle

    2014-01-01

    for the elaboration of pollution control strategies (including both source control and treatment options) at the small spatial scale of urban areas. Existing and well-established water quality models for the different parts of the IUWS (e.g. ASM models) are extended by adding MP fate processes. These are modelled......The increasing efforts in reducing the emission of micropollutants (MP) into the natural aquatic environment require the development of modelling tools to support the decision making process. This article presents a library of dynamic modelling tools for estimating MP fluxes within Integrated Urban...... Wastewater and Stormwater system (IUWS – including drainage network, stormwater treatment units, wastewater treatment plants, sludge treatment, and the receiving water body). The models are developed by considering the high temporal variability of the processes taking place in the IUWS, providing a basis...

  6. TRADING STORMWATER ABATEMENT CREDITS IN CINCINNATI'S SHEPHERD CREEK

    Science.gov (United States)

    The problem of stormwater runoff management grows apace with continued urbanization, yet the management tools for this growning non-profit source problem have not fully kept pace. The rapid growth of stormwater utilities around the nation is an important step toward providing an...

  7. Toward an operational tool to simulate green roof hydrological impact at the basin scale: a new version of the distributed rainfall-runoff model Multi-Hydro.

    Science.gov (United States)

    Versini, Pierre-Antoine; Gires, Auguste; Tchinguirinskaia, Ioulia; Schertzer, Daniel

    2016-10-01

    Currently widespread in new urban projects, green roofs have shown a positive impact on urban runoff at the building scale: decrease and slow-down of the peak discharge, and decrease of runoff volume. The present work aims to study their possible impact at the catchment scale, more compatible with stormwater management issues. For this purpose, a specific module dedicated to simulating the hydrological behaviour of a green roof has been developed in the distributed rainfall-runoff model (Multi-Hydro). It has been applied on a French urban catchment where most of the building roofs are flat and assumed to accept the implementation of a green roof. Catchment responses to several rainfall events covering a wide range of meteorological situations have been simulated. The simulation results show green roofs can significantly reduce runoff volume and the magnitude of peak discharge (up to 80%) depending on the rainfall event and initial saturation of the substrate. Additional tests have been made to assess the susceptibility of this response regarding both spatial distributions of green roofs and precipitation. It appears that the total area of greened roofs is more important than their locations. On the other hand, peak discharge reduction seems to be clearly dependent on spatial distribution of precipitation.

  8. A case study demonstrating analysis of stormflows, concentrations, and loads of nutrients in highway runoff and swale discharge with the Stochastic Empirical Loading and Dilution Model (SELDM)

    Science.gov (United States)

    Granato, Gregory; Jones, Susan C.

    2015-01-01

    Decisionmakers need information about the quality and quantity of stormwater runoff, the risk for adverse effects of runoff on receiving waters, and the potential effectiveness of mitigation measures to reduce these risks. The Stochastic Empirical Loading and Dilution Model (SELDM) uses Monte Carlo methods to generate stormflows, concentrations, and loads from a highway site and an upstream basin to provide needed risk-based information. SELDM was designed to help inform water-management decisions for streams and lakes receiving runoff from a highway or other land-use site. The purpose of this paper is to provide a brief description of SELDM and a hypothetical case study demonstrating the type of risk-based information that SELDM can provide. Total nitrogen (TN) and total phosphorus (TP) were selected as example constituents because nutrients are a common concern throughout the Nation and data for receiving waters, highway runoff, and the performance of best management practices (BMPs) are readily available for these constituents. 

  9. Effects of low-impact-development (LID) practices on streamflow, runoff quantity, and runoff quality in the Ipswich River Basin, Massachusetts-A Summary of field and modeling studies

    Science.gov (United States)

    Zimmerman, Marc J.; Waldron, Marcus C.; Barbaro, Jeffrey R.; Sorenson, Jason R.

    2010-01-01

    Low-impact-development (LID) approaches are intended to create, retain, or restore natural hydrologic and water-quality conditions that may be affected by human alterations. Wide-scale implementation of LID techniques may offer the possibility of improving conditions in river basins, such as the Ipswich River Basin in Massachusetts, that have run dry during the summer because of groundwater withdrawals and drought. From 2005 to 2008, the U.S. Geological Survey, in a cooperative funding agreement with the Massachusetts Department of Conservation and Recreation, monitored small-scale installations of LID enhancements designed to diminish the effects of storm runoff on the quantity and quality of surface water and groundwater. Funding for the studies also was contributed by the U.S. Environmental Protection Agency's Targeted Watersheds Grant Program through a financial assistance agreement with Massachusetts Department of Conservation and Recreation. The monitoring studies examined the effects of * replacing an impervious parking-lot surface with a porous surface on groundwater quality, * installing rain gardens and porous pavement in a neighborhood of 3 acres on the quantity and quality of stormwater runoff, and * installing a 3,000-ft2 (square-foot) green roof on the quantity and quality of rainfall-generated roof runoff. In addition to these small-scale installations, the U.S. Geological Survey's Ipswich River Basin model was used to simulate the basin-wide effects on streamflow of several changes: broad-scale implementation of LID techniques, reduced water-supply withdrawals, and water-conservation measures. Water-supply and conservation scenarios for application in model simulations were developed with the assistance of two technical advisory committees that included representatives of State agencies responsible for water resources, the U.S. Environmental Protection Agency, the U.S. Geological Survey, water suppliers, and non-governmental organizations. From June

  10. Model based historical runoff contribution from an Alpine glacier

    Science.gov (United States)

    Zoccatelli, Davide; Bonato, Paola; Carturan, Luca; Dalla Fontana, Giancarlo; De Blasi, Fabrizio; Borga, Marco

    2016-04-01

    The aim of this work is to analyze how climatic variability and glacier retreat impact the water balance of a small (8.5 km2) glaciarised catchment in the Eastern Italia Alps over a 30 year (1983-2013) period. The analysis is carried out by coupling local high quality data and a glacio-hydrological model able to simulate both the glacier and hydrology dynamics. Runoff contribution from glacier ice is related with trends in climatic variables and with glacier retreat. The area analyzed is the headwater of Noce Bianco river basin, lying in the Ortles-Cevedale group and including the La Mare glacier. During the study period the glacier area decreased from 4.7 km2 (50% basin area) to 3.47 km2 (40% basin area). In this area the following observations are available: 30 years of daily meteorological data at high elevation close to the catchment; three DTMs of the glacier, covering the entire period, which enable the calculation of the volume change and geodetic mass balance; direct glaciological mass balance observations over the period 2003-2013; discharge measurement at the catchment outlet over the period 2007-2013. The data availability and the significant shrinking of the glacier during the analyzed period make this catchment ideal for studying the hydrological impacts of glacier retreat. The semi-distributed conceptual model includes a snow and glacier accumulation and ablation module, based on temperature-radiation index and a glacier retreat model. The glacier retreat model allows to use the annual simulated glacier mass balance to update the glacier area (Huss et al., 2010). The model simulations are carried out from 1983 to 2013. We show that the model is able to capture adequately the measured daily discharge, the observed changes in glacier area and their spatial distribution. The contribution of glacier ice meltwater to annual runoff is below 10% in the first decade of simulation. This variable however showed a clear increasing trend, with peaks for single

  11. Organic Nitrogen Concentrations and Trends in Urban Stormwater: Implications for Stormwater Monitoring and Management

    Science.gov (United States)

    Lusk, M. G.; Toor, G.

    2014-12-01

    Organic nitrogen (ON) can be a significant contributor of bioavailable N to the phytoplankton and bacteria that cause eutrophication and harmful algal blooms. In urban systems, urban stormwater runoff containing ON compounds is one source of potentially bioavailable N in water bodies. However, ON characterization and concentrations in urban stormwater are rarely reported or considered for urban stormwater management. We instrumented a 13-hectare residential catchment in Florida's Tampa Bay area with an ISCO autosampler and collected storm event runoff samples at 15-minute intervals during the 2013 wet season (June to September, n =236). Our objectives were to determine the (1) relative importance of ON compared to inorganic N forms (i.e., NO3- and NH4+) in the runoff, (2) investigate temporal trends in the ON concentrations in runoff, and (3) assess how rainfall depth and intensity affect any temporal trends. Mean concentration of total N in stormwater runoff for the wet season was 1.86 mg/l, of which dissolved and particulate ON were 63%. The dominance of ON in urban stormwater runoff suggests that the ON fraction should also be targeted when stormwater control measures call for N reductions. Particulate ON (PON) displayed a strong seasonal first flush trend as season progressed from June (1.45 mg/l; n =75) to September (0.20 mg/l; n = 28), while dissolved ON (DON) did not display any seasonal trend, with mean monthly concentrations ranging from 0.36 to 0.80 mg/l. A principal component analysis using storm event N concentrations, rainfall depth, and rainfall intensity as variables showed no significant correlation, suggesting that storms of various sizes and intensities can mobilize ON. The seasonal first flush observed for PON in the wet season can provide a window of time for optimal N removal and implies that stormwater best management practices should focus on capturing plant materials earlier in the season.

  12. DEMFIL - treatment of stormwater for recreational use

    DEFF Research Database (Denmark)

    Sørud, Mai; Nielsen, Katrine; Skau Damskier, Sophie;

    2013-01-01

    Decoupling of stormwater (road runoff) in a residential area has been implemented in order to reduce flooding and to increase the hydraulic capacity of a lake with a high recreational value. The object here was to evaluate a disc filter technology in combination with a green polymer for flocculat......Decoupling of stormwater (road runoff) in a residential area has been implemented in order to reduce flooding and to increase the hydraulic capacity of a lake with a high recreational value. The object here was to evaluate a disc filter technology in combination with a green polymer...

  13. Stormwater Bioretention: Nitrogen, Phosphorous and Metal Removal by Plants

    OpenAIRE

    Rycewicz-Borecki, Malgorzata

    2015-01-01

    Stormwater runoff may contain high levels of pollutants and is regulated by the Federal National Pollution Discharge Elimination System (NPDES). Stormwater bioretention (BR) systems are often used to satisfy these regulations. BR systems collect accumulated runoff that leaches into groundwater. A greenhouse study evaluated nutrient and metal removal among plant species that are typically found growing in BR systems. A field demonstration study assessed citric acid enhanced metal bioaccumulati...

  14. [Advances in low impact development technology for urban stormwater management].

    Science.gov (United States)

    Liu, Wen; Chen, Wei-ping; Peng, Chi

    2015-06-01

    Low impact development ( LID), as an innovative technology for stormwater management, is effective to mitigate urban flooding and to detain pollutants. This paper systemically introduced the LID technology system, and summarized the reduction effects of three typical LID facilities (i.e. , bio-retention, green roof and permeable pavement) on stormwater runoff and main pollutants in recent literature, as well as research outcomes and experiences of LID technology on model simulation, cost-benefit analysis and management system. On this basis, we analyzed the problems and limitations of current LID technology studies. Finally, some suggestions about future research directions, appropriate design and scientific management were put forth. This work intended to provide scientific basis and suggestions for widespread use and standard setting of LID technology in China by referencing overseas studies.

  15. Characterization of storm runoff from selected South Carolina Department of Transportation maintenance yards

    Science.gov (United States)

    Conlon, Kevin J.; Reinhart, Peter J.

    2012-01-01

    The objective of this project is to collect sufficient stormwater water-quality and flow data to document the type, concentration, and event load of selected constituents transported from South Carolina Department of Transportation (SCDOT) maintenance yards by stormwater runoff.

  16. Zebrafish and clean water technology: assessing soil bioretention as a protective treatment for toxic urban runoff.

    Science.gov (United States)

    McIntyre, J K; Davis, J W; Incardona, J P; Stark, J D; Anulacion, B F; Scholz, N L

    2014-12-01

    Urban stormwater contains a complex mixture of contaminants that can be acutely toxic to aquatic biota. Green stormwater infrastructure (GSI) is a set of evolving technologies intended to reduce impacts on natural systems by slowing and filtering runoff. The extent to which GSI methods work as intended is usually assessed in terms of water quantity (hydrology) and quality (chemistry). Biological indicators of GSI effectiveness have received less attention, despite an overarching goal of protecting the health of aquatic species. Here we use the zebrafish (Danio rerio) experimental model to evaluate bioinfiltration as a relatively inexpensive technology for treating runoff from an urban highway with dense motor vehicle traffic. Zebrafish embryos exposed to untreated runoff (48-96h; six storm events) displayed an array of developmental abnormalities, including delayed hatching, reduced growth, pericardial edema, microphthalmia (small eyes), and reduced swim bladder inflation. Three of the six storms were acutely lethal, and sublethal toxicity was evident across all storms, even when stormwater was diluted by as much as 95% in clean water. As anticipated from exposure to cardiotoxic polycyclic aromatic hydrocarbons (PAHs), untreated runoff also caused heart failure, as indicated by circulatory stasis, pericardial edema, and looping defects. Bioretention treatment dramatically improved stormwater quality and reversed nearly all forms of developmental toxicity. The zebrafish model therefore provides a versatile experimental platform for rapidly assessing GSI effectiveness.

  17. Regionalization parameters of conceptual rainfall-runoff model

    Science.gov (United States)

    Osuch, M.

    2003-04-01

    Main goal of this study was to develop techniques for the a priori estimation parameters of hydrological model. Conceptual hydrological model CLIRUN was applied to around 50 catchment in Poland. The size of catchments range from 1 000 to 100 000 km2. The model was calibrated for a number of gauged catchments with different catchment characteristics. The parameters of model were related to different climatic and physical catchment characteristics (topography, land use, vegetation and soil type). The relationships were tested by comparing observed and simulated runoff series from the gauged catchment that were not used in the calibration. The model performance using regional parameters was promising for most of the calibration and validation catchments.

  18. Calibration of Conceptual Rainfall-Runoff Models Using Global Optimization

    Directory of Open Access Journals (Sweden)

    Chao Zhang

    2015-01-01

    Full Text Available Parameter optimization for the conceptual rainfall-runoff (CRR model has always been the difficult problem in hydrology since watershed hydrological model is high-dimensional and nonlinear with multimodal and nonconvex response surface and its parameters are obviously related and complementary. In the research presented here, the shuffled complex evolution (SCE-UA global optimization method was used to calibrate the Xinanjiang (XAJ model. We defined the ideal data and applied the method to observed data. Our results show that, in the case of ideal data, the data length did not affect the parameter optimization for the hydrological model. If the objective function was selected appropriately, the proposed method found the true parameter values. In the case of observed data, we applied the technique to different lengths of data (1, 2, and 3 years and compared the results with ideal data. We found that errors in the data and model structure lead to significant uncertainties in the parameter optimization.

  19. Analyzing runoff processes through conceptual hydrological modelling in the Upper Blue Nile basin, Ethiopia

    Directory of Open Access Journals (Sweden)

    M. Dessie

    2014-05-01

    Full Text Available Understanding runoff processes in a basin is of paramount importance for the effective planning and management of water resources, in particular in data scarce regions of the Upper Blue Nile. Hydrological models representing the underlying hydrological processes can predict river discharges from ungauged catchments and allow for an understanding of the rainfall–runoff processes in those catchments. In this paper, such a conceptual process-based hydrological model is developed and applied to the upper Gumara and Gilgel Abay catchments (both located within the Upper Blue Nile basin, the Lake Tana sub-basin to study the runoff mechanisms and rainfall–runoff processes in the basin. Topography is considered as a proxy for the variability of most of the catchment characteristics. We divided the catchments into different runoff production areas using topographic criteria. Impermeable surfaces (rock outcrops and hard soil pans, common in the Upper Blue Nile basin were considered separately in the conceptual model. Based on model results, it can be inferred that about 65% of the runoff appears in the form of interflow in the Gumara study catchment, and baseflow constitutes the larger proportion of runoff (44–48% in the Gilgel Abay catchment. Direct runoff represents a smaller fraction of the runoff in both catchments (18–19% for the Gumara, and 20% for the Gilgel Abay and most of this direct runoff is generated through infiltration excess runoff mechanism from the impermeable rocks or hard soil pans. The study reveals that the hillslopes are recharge areas (sources of interflow and deep percolation and direct runoff as saturated excess flow prevails from the flat slope areas. Overall, the model study suggests that identifying the catchments into different runoff production areas based on topography and including the impermeable rocky areas separately in the modeling process mimics well the rainfall–runoff process in the Upper Blue Nile basin

  20. Using the snowmelt runoff model to evaluate climate change effects and to compare basin runoff between New Mexico and Idaho.

    Science.gov (United States)

    The Snowmelt Runoff Model(SRM) has been developed and tested in small to large basins worldwide. SRM has been found to be very useful for understanding snowmelt processes as well as for simulating or forecasting snowmelt-derived water supplies. SRM is being used in New Mexico in a NSF-funded EPSCo...

  1. Predicting hydrological signatures in ungauged catchments using spatial interpolation, index model, and rainfall-runoff modelling

    Science.gov (United States)

    Zhang, Yongqiang; Vaze, Jai; Chiew, Francis H. S.; Teng, Jin; Li, Ming

    2014-09-01

    Understanding a catchment's behaviours in terms of its underlying hydrological signatures is a fundamental task in surface water hydrology. It can help in water resource management, catchment classification, and prediction of runoff time series. This study investigated three approaches for predicting six hydrological signatures in southeastern Australia. These approaches were (1) spatial interpolation with three weighting schemes, (2) index model that estimates hydrological signatures using catchment characteristics, and (3) classical rainfall-runoff modelling. The six hydrological signatures fell into two categories: (1) long-term aggregated signatures - annual runoff coefficient, mean of log-transformed daily runoff, and zero flow ratio, and (2) signatures obtained from daily flow metrics - concavity index, seasonality ratio of runoff, and standard deviation of log-transformed daily flow. A total of 228 unregulated catchments were selected, with half the catchments randomly selected as gauged (or donors) for model building and the rest considered as ungauged (or receivers) to evaluate performance of the three approaches. The results showed that for two long-term aggregated signatures - the log-transformed daily runoff and runoff coefficient, the index model and rainfall-runoff modelling performed similarly, and were better than the spatial interpolation methods. For the zero flow ratio, the index model was best and the rainfall-runoff modelling performed worst. The other three signatures, derived from daily flow metrics and considered to be salient flow characteristics, were best predicted by the spatial interpolation methods of inverse distance weighting (IDW) and kriging. Comparison of flow duration curves predicted by the three approaches showed that the IDW method was best. The results found here provide guidelines for choosing the most appropriate approach for predicting hydrological behaviours at large scales.

  2. Sensitivity-Based Modeling of Evaluating Surface Runoff and Sediment Load using Digital and Analog Mechanisms

    Directory of Open Access Journals (Sweden)

    Olotu Yahaya

    2014-07-01

    Full Text Available Analyses of runoff- sediment measurement and evaluation using automated and convectional runoff-meters was carried out at Meteorological and Hydrological Station of Auchi Polytechnic, Auchi using two runoff plots (ABCDa and EFGHm of area 2m 2 each, depth 0.26 m and driven into the soil to the depth of 0.13m. Runoff depths and intensities were measured from each of the positioned runoff plot. Automated runoff-meter has a measuring accuracy of ±0.001l/±0.025 mm and rainfall depth-intensity was measured using tipping-bucket rainguage during the period of 14-month of experimentation. Minimum and maximum rainfall depths of 1.2 and 190.3 mm correspond to measured runoff depths (MRo of 0.0 mm for both measurement approaches and 60.4 mm and 48.9 mm respectively. Automated runoffmeter provides precise, accurate and instantaneous result over the convectional measurement of surface runoff. Runoff measuring accuracy for automated runoff-meter from the plot (ABCDa produces R 2 = 0.99; while R 2 = 0.96 for manual evaluation in plot (EFGHm. WEPP and SWAT models were used to simulate the obtained hydrological variables from the applied measurement mechanisms. The outputs of sensitivity simulation analysis indicate that data from automated measuring systems gives a better modelling index and such could be used for running robust runoff-sediment predictive modelling technique under different reservoir sedimentation and water management scenarios.

  3. Stormwater Management Effects on Ecosystem Services: A Literature Review

    Science.gov (United States)

    Prudencio, L.; Null, S. E.

    2016-12-01

    Managing stormwater provides benefits for enhancing water supplies while reducing urban runoff. Yet, there has been little research focused on understanding how stormwater management affects ecosystem services, the benefits that ecosystems provide to humans. Garnering more knowledge of the changes to ecosystem services from stormwater management will ultimately improve management and decision-making. The objective of this research is to review and synthesize published literature on 1) ecosystem services and stormwater management and 2) changes in ecosystem services from anthropogenic impacts and climate warming, to establish a foundation for research at the intersection of ecosystems services, stormwater management, and global environmental change. We outline four research areas for ecosystem services and stormwater management that should be further explored. These four areas, named after the four types of ecosystem services, highlight context-specific research questions and human and climate change effects. We conclude that effective and sustainable stormwater management requires incorporating engineering, social, and environmental criteria to quantify benefits of provisioning, regulating, cultural, and supporting ecosystem services. Lastly, improved current and potential stormwater management policy may better support sustainable stormwater methods at the institutional level. Stormwater quality and monitoring could be improved through the use of the Clean Water Act (e.g. Total Maximum Daily Loads), the Endangered Species Act, and public health measures. Additional policies regulating groundwater quantity and quality have been and may continue to be implemented by states, encouraging sustainable and cleaner stormwater practices.

  4. Hydrologic, Social, and Economic Efficacy of Green Infrastructure Credit Programs: Toward Citizen Stormwater Management

    Science.gov (United States)

    Green, O. O.; Kertesz, R.; Rossman, L.; Shuster, W.

    2013-12-01

    Fostering 'citizen stormwater management', whereby citizens make stormwater management a part of their everyday lives, aims to improve the resilience of the urban water social-ecological system by reducing the load on the stormwater collection system through investment in natural and social capitals. A popular method of incentivizing citizen stormwater management is offering stormwater fee discounts as credits for the installation of green infrastructure onsite. Such installations, in effect, reduce the amount of impervious area by disconnecting them from the sewer system. We analyze 4 such programs (Portland OR, Cleveland OH, Fort Myers FL, and Lynchburg VA) which offer discounts to single family residences for installing rain gardens or bioinfiltration features. Findings indicate large variability in the hydrological, social, and economic efficacy of these programs. We assessed hydrologic efficacy using the Environmental Protection Agency's recently released Stormwater Calculator, a user-friendly model based on SWMM. Hydrologic efficacy was most sensitive to level of detail in administrative rules (i.e., specifics pertaining to soil drainage, slope), regional conditions (e.g., precipitation) and local conditions (e.g., soil, percent of impervious area treated). Social efficacy was measured by the accessibility of the programs to average citizens and varied from highly accessible programs, whereby municipalities had sufficient outreach efforts such that average residents could install their own green infrastructure, to programs with no outreach and contradictory rules which would require a professional engineer to navigate the process and install an eligible rain garden. Economic efficiency was largely dependent on the base stormwater fee (i.e., higher baseline bill results in higher discount and thus higher incentive to participate). From the perspective of a homeowner, they may receive a windfall (i.e., % runoff reduced < % discount), yet due to the low baseline

  5. Runoff prediction using an integrated hybrid modelling scheme

    Science.gov (United States)

    Remesan, Renji; Shamim, Muhammad Ali; Han, Dawei; Mathew, Jimson

    2009-06-01

    SummaryRainfall runoff is a very complicated process due to its nonlinear and multidimensional dynamics, and hence difficult to model. There are several options for a modeller to consider, for example: the type of input data to be used, the length of model calibration (training) data and whether or not the input data be treated as signals with different frequency bands so that they can be modelled separately. This paper describes a new hybrid modelling scheme to answer the above mentioned questions. The proposed methodology is based on a hybrid model integrating wavelet transformation, a modelling engine (Artificial Neural Network) and the Gamma Test. First, the Gamma Test is used to decide the required input data dimensions and its length. Second, the wavelet transformation decomposes the input signals into different frequency bands. Finally, a modelling engine (ANN in this study) is used to model the decomposed signals separately. The proposed scheme was tested using the Brue catchment, Southwest England, as a case study and has produced very positive results. The hybrid model outperforms all other models tested. This study has a wider implication in the hydrological modelling field since its general framework could be applied to other model combinations (e.g., model engine could be Support Vector Machines, neuro-fuzzy systems, or even a conceptual model. The signal decomposition could be carried out by Fourier transformation).

  6. Erosivity, surface runoff, and soil erosion estimation using GIS-coupled runoff-erosion model in the Mamuaba catchment, Brazil.

    Science.gov (United States)

    Marques da Silva, Richarde; Guimarães Santos, Celso Augusto; Carneiro de Lima Silva, Valeriano; Pereira e Silva, Leonardo

    2013-11-01

    This study evaluates erosivity, surface runoff generation, and soil erosion rates for Mamuaba catchment, sub-catchment of Gramame River basin (Brazil) by using the ArcView Soil and Water Assessment Tool (AvSWAT) model. Calibration and validation of the model was performed on monthly basis, and it could simulate surface runoff and soil erosion to a good level of accuracy. Daily rainfall data between 1969 and 1989 from six rain gauges were used, and the monthly rainfall erosivity of each station was computed for all the studied years. In order to evaluate the calibration and validation of the model, monthly runoff data between January 1978 and April 1982 from one runoff gauge were used as well. The estimated soil loss rates were also realistic when compared to what can be observed in the field and to results from previous studies around of catchment. The long-term average soil loss was estimated at 9.4 t ha(-1) year(-1); most of the area of the catchment (60%) was predicted to suffer from a low- to moderate-erosion risk (catchment, the soil erosion was estimated to exceed > 12 t ha(-1) year(-1). Expectedly, estimated soil loss was significantly correlated with measured rainfall and simulated surface runoff. Based on the estimated soil loss rates, the catchment was divided into four priority categories (low, moderate, high and very high) for conservation intervention. The study demonstrates that the AvSWAT model provides a useful tool for soil erosion assessment from catchments and facilitates the planning for a sustainable land management in northeastern Brazil.

  7. Optimizing selection of decentralized stormwater management strategies in urbanized regions

    Science.gov (United States)

    Yu, Z.; Montalto, F.

    2011-12-01

    A variety of decentralized stormwater options are available for implementation in urbanized regions. These strategies, which include bio-retention, porous pavement, green roof etc., vary in terms of cost, ability to reduce runoff, and site applicability. This paper explores the tradeoffs between different types of stormwater control meastures that could be applied in a typical urban study area. A nested optimization strategy first identifies the most cost-effective (e.g. runoff reduction / life cycle cost invested ) options for individual land parcel typologies, and then scales up the results with detailed attention paid to uncertainty in adoption rates, life cycle costs, and hydrologic performance. The study is performed with a custom built stochastic rainfall-runoff model (Monte Carlo techniques are used to quantify uncertainties associated with phased implementation of different strategies and different land parcel typologies under synthetic precipitation ensembles). The results are presented as a comparison of cost-effectiveness over the time span of 30 years, and state an optimized strategy on the cumulative cost-effectiveness over the period.

  8. The Wageningen Lowland Runoff Simulator (WALRUS): a lumped rainfall-runoff model for catchments with shallow groundwater

    Science.gov (United States)

    Brauer, C. C.; Teuling, A. J.; Torfs, P. J. J. F.; Uijlenhoet, R.

    2014-10-01

    We present the Wageningen Lowland Runoff Simulator (WALRUS), a novel rainfall-runoff model to fill the gap between complex, spatially distributed models which are often used in lowland catchments and simple, parametric (conceptual) models which have mostly been developed for sloping catchments. WALRUS explicitly accounts for processes that are important in lowland areas, notably (1) groundwater-unsaturated zone coupling, (2) wetness-dependent flow routes, (3) groundwater-surface water feedbacks and (4) seepage and surface water supply. WALRUS consists of a coupled groundwater-vadose zone reservoir, a quickflow reservoir and a surface water reservoir. WALRUS is suitable for operational use because it is computationally efficient and numerically stable (achieved with a flexible time step approach). In the open source model code default relations have been implemented, leaving only four parameters which require calibration. For research purposes, these defaults can easily be changed. Numerical experiments show that the implemented feedbacks have the desired effect on the system variables.

  9. Runoff Modelling in Urban Storm Drainage by Neural Networks

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Brorsen, Michael; Schaarup-Jensen, Kjeld

    1995-01-01

    network is used to compute flow or water level at selected points in the sewer system, and to forecast the flow from a small residential area. The main advantages of the neural network are the build-in self calibration procedure and high speed performance, but the neural network cannot be used to extract......A neural network is used to simulate folw and water levels in a sewer system. The calibration of th neural network is based on a few measured events and the network is validated against measureed events as well as flow simulated with the MOUSE model (Lindberg and Joergensen, 1986). The neural...... knowledge of the runoff process. The neural network was found to simulate 150 times faster than e.g. the MOUSE model....

  10. Characterizing the impact of spatiotemporal variations in stormwater infrastructure on hydrologic conditions

    Science.gov (United States)

    Jovanovic, T.; Mejia, A.; Hale, R. L.; Gironas, J. A.

    2015-12-01

    Urban stormwater infrastructure design has evolved in time, reflecting changes in stormwater policy and regulations, and in engineering design. This evolution makes urban basins heterogeneous socio-ecological-technological systems. We hypothesize that this heterogeneity creates unique impact trajectories in time and impact hotspots in space within and across cities. To explore this, we develop and implement a network hydro-engineering modeling framework based on high-resolution digital elevation and stormwater infrastructure data. The framework also accounts for climatic, soils, land use, and vegetation conditions in an urban basin, thus making it useful to study the impacts of stormwater infrastructure across cities. Here, to evaluate the framework, we apply it to urban basins in the metropolitan areas of Phoenix, Arizona. We use it to estimate different metrics to characterize the storm-event hydrologic response. We estimate both traditional metrics (e.g., peak flow, time to peak, and runoff volume) as well as new metrics (e.g., basin-scale dispersion mechanisms). We also use the dispersion mechanisms to assess the scaling characteristics of urban basins. Ultimately, we find that the proposed framework can be used to understand and characterize the impacts associated with stormwater infrastructure on hydrologic conditions within a basin. Additionally, we find that the scaling approach helps in synthesizing information but it requires further validation using additional urban basins.

  11. Economic Incentives for Stormwater Control (ISBN9781439845608)

    Science.gov (United States)

    Addressing a huge knowledge gap from a policy perspective, this book focuses on the economic tools available for stormwater runoff control. It provides case studies demonstrating the application of various incentives, such as tradable credits, fees with rebates, and auction mecha...

  12. STORMWATER FILTRATION USING MULCH AND JUTE

    Science.gov (United States)

    This study evaluated the feasibility of using readily available, low-cost natural filter naterials for stormwater (SW) treatment. Generic (hardwood) mulch and processed jute fiber were evaluated for the removal of metallic and organic pollutants from urban SW runoff samples colle...

  13. USING TRADABLE CREDITS TO MANAGE STORMWATER

    Science.gov (United States)

    Excess stormwater runoff causes degradation of urban stream habitat through conveyance of pollutants and disruption of normal stream flow regimes. Following on acceptance of tradable permits as a mechanism for reducing certain air pollutants, we propose the use of a system of tra...

  14. USING TRADABLE CREDITS TO MANAGE STORMWATER

    Science.gov (United States)

    Excess stormwater runoff causes degradation of urban stream habitat through conveyance of pollutants and disruption of normal stream flow regimes. Following on acceptance of tradable permits as a mechanism for reducing certain air pollutants, we propose the use of a system of tra...

  15. Best management practices for airport deicing stormwater.

    Science.gov (United States)

    Switzenbaum, M S; Veltman, S; Mericas, D; Wagoner, B; Schoenberg, T

    2001-06-01

    With the advent of new regulations concerning aircraft deicing and management of spent aircraft deicing fluids (ADFs), many airports now face the dual challenges of simultaneously maintaining public safety and protecting the environment. This paper provides a theoretical assessment of the potential environmental impact of stormwater runoff and offers detailed current information on alternative deicing fluid application methods and materials, collection and treatment practices.

  16. 雨洪管理模型SWMM的原理、参数和应用%Stormwater Management Model (SWMM) : Principles, Parameters and Applications

    Institute of Scientific and Technical Information of China (English)

    陈晓燕; 张娜; 吴芳芳; 贺兵

    2013-01-01

    Stormwater management model (SWMM) is a model most suitable for estimating surface runoff and its pollution load among the widely used models. SWMM has been successfully used in estimating and predicting surface runoff processes, surface runoff and pollution load during storm floods in urban areas, and planning, analyzing and designing combined and separate sewers, sewage pipes and other drainage systems. The main principles of modules of SWMM and their estimations were analyzed, and the calibration methods for main parameters and their sensitivities were summarized. It was found that the sensitive parameters in SWMM included percent of impervious area, surface infiltration capacity, width of overland flow path, depth of depression storage of impervious surface, length and internal diameter of conduit. Several existing problems in SWMM and corresponding suggestions for the future improvements were proposed.%对目前应用较广泛的地表径流污染负荷估算模型的分析表明,雨洪管理模型SWMM(Storm Water Management Model)是最适合于城市地表径流及其污染负荷研究的模型.SWMM已在国内外城市地区暴雨洪水的地表径流过程、地表径流量和污染负荷量的估算与预测,以及对合流式和分流式下水道、排污管道和其他排水系统的规划、分析、设计方面获得了成功应用.深入分析了SWMM中主要模块的基本原理和计算过程,总结了校准主要参数的方法;并对主要参数的敏感性进行了分析和总结,得出SWMM的敏感参数主要包括非渗透面积比例、地表渗透能力、坡面漫流宽度、非渗透地表洼蓄贮存深度、导管的长度和内径.最后,提出了SWMM尚存在的问题及今后的改进方向.

  17. A top-down model to generate ensembles of runoff from a large number of hillslopes

    Directory of Open Access Journals (Sweden)

    P. R. Furey

    2013-09-01

    Full Text Available We hypothesize that total hillslope water loss for a rainfall–runoff event is inversely related to a function of a lognormal random variable, based on basin- and point-scale observations taken from the 21 km2 Goodwin Creek Experimental Watershed (GCEW in Mississippi, USA. A top-down approach is used to develop a new runoff generation model both to test our physical-statistical hypothesis and to provide a method of generating ensembles of runoff from a large number of hillslopes in a basin. The model is based on the assumption that the probability distributions of a runoff/loss ratio have a space–time rescaling property. We test this assumption using streamflow and rainfall data from GCEW. For over 100 rainfall–runoff events, we find that the spatial probability distributions of a runoff/loss ratio can be rescaled to a new distribution that is common to all events. We interpret random within-event differences in runoff/loss ratios in the model to arise from soil moisture spatial variability. Observations of water loss during events in GCEW support this interpretation. Our model preserves water balance in a mean statistical sense and supports our hypothesis. As an example, we use the model to generate ensembles of runoff at a large number of hillslopes for a rainfall–runoff event in GCEW.

  18. A top-down model to generate ensembles of runoff from a large number of hillslopes

    Science.gov (United States)

    Furey, P. R.; Gupta, V. K.; Troutman, B. M.

    2013-09-01

    We hypothesize that total hillslope water loss for a rainfall-runoff event is inversely related to a function of a lognormal random variable, based on basin- and point-scale observations taken from the 21 km2 Goodwin Creek Experimental Watershed (GCEW) in Mississippi, USA. A top-down approach is used to develop a new runoff generation model both to test our physical-statistical hypothesis and to provide a method of generating ensembles of runoff from a large number of hillslopes in a basin. The model is based on the assumption that the probability distributions of a runoff/loss ratio have a space-time rescaling property. We test this assumption using streamflow and rainfall data from GCEW. For over 100 rainfall-runoff events, we find that the spatial probability distributions of a runoff/loss ratio can be rescaled to a new distribution that is common to all events. We interpret random within-event differences in runoff/loss ratios in the model to arise from soil moisture spatial variability. Observations of water loss during events in GCEW support this interpretation. Our model preserves water balance in a mean statistical sense and supports our hypothesis. As an example, we use the model to generate ensembles of runoff at a large number of hillslopes for a rainfall-runoff event in GCEW.

  19. Comparison of rainfall-runoff models for flood forecasting. Part 2: Calibration and evaluation of models

    OpenAIRE

    Bell, V. A.; Carrington, D.S.; Moore, R J

    2001-01-01

    The purpose of the project “Comparison of Rainfall-Runoff Models for Flood Forecasting” is to provide guidance to the Environment Agency on the choice of rainfall-runoff model for use in different catchments for flood forecasting purposes. A literature review of models presented in the Part 1 Report recognised that whilst there is a plethora of “brand-name” models there is much similarity between many of them. A rather small set of model functions is common to many models and they differ in t...

  20. Possibilistic uncertainty analysis of a conceptual model of snowmelt runoff

    Directory of Open Access Journals (Sweden)

    A. P. Jacquin

    2010-03-01

    Full Text Available This study presents the analysis of predictive uncertainty of a conceptual type snowmelt runoff model. The method applied uses possibilistic rather than probabilistic calculus for the evaluation of predictive uncertainty. Possibility theory is an information theory meant to model uncertainties caused by imprecise or incomplete knowledge about a real system rather than by randomness. A snow dominated catchment in the Chilean Andes is used as case study. Predictive uncertainty arising from parameter uncertainties of the watershed model is assessed. Model performance is evaluated according to several criteria, in order to define the possibility distribution of the model representations. The likelihood of the simulated glacier mass balance and snow cover are used for further assessing model credibility. Possibility distributions of the discharge estimates and prediction uncertainty bounds are subsequently derived. The results of the study indicate that the use of additional information allows a reduction of predictive uncertainty. In particular, the assessment of the simulated glacier mass balance and snow cover helps to reduce the width of the uncertainty bounds without a significant increment in the number of unbounded observations.

  1. Markov-switching model for nonstationary runoff conditioned on El Nino information

    DEFF Research Database (Denmark)

    Gelati, Emiliano; Madsen, H.; Rosbjerg, Dan

    2010-01-01

    of the climatic input. MARX allows stochastic modeling of nonstationary runoff, as runoff anomalies are described by a mixture of autoregressive models with exogenous input, each one corresponding to a climate state. We apply MARX to inflow time series of the Daule Peripa reservoir (Ecuador). El Nino Southern...

  2. Possibilistic uncertainty analysis of a conceptual model of snowmelt runoff

    Directory of Open Access Journals (Sweden)

    A. P. Jacquin

    2010-08-01

    Full Text Available This study presents the analysis of predictive uncertainty of a conceptual type snowmelt runoff model. The method applied uses possibilistic rather than probabilistic calculus for the evaluation of predictive uncertainty. Possibility theory is an information theory meant to model uncertainties caused by imprecise or incomplete knowledge about a real system rather than by randomness. A snow dominated catchment in the Chilean Andes is used as case study. Predictive uncertainty arising from parameter uncertainties of the watershed model is assessed. Model performance is evaluated according to several criteria, in order to define the possibility distribution of the parameter vector. The plausibility of the simulated glacier mass balance and snow cover are used for further constraining the model representations. Possibility distributions of the discharge estimates and prediction uncertainty bounds are subsequently derived. The results of the study indicate that the use of additional information allows a reduction of predictive uncertainty. In particular, the assessment of the simulated glacier mass balance and snow cover helps to reduce the width of the uncertainty bounds without a significant increment in the number of unbounded observations.

  3. An application of artificial intelligence for rainfall–runoff modeling

    Indian Academy of Sciences (India)

    Ali Aytek; M Asce; Murat Alp

    2008-04-01

    This study proposes an application of two techniques of artificial intelligence (AI) for rainfall–runoff modeling: the artificial neural networks (ANN) and the evolutionary computation (EC). Two different ANN techniques, the feed forward back propagation (FFBP) and generalized regression neural network (GRNN) methods are compared with one EC method, Gene Expression Programming (GEP) which is a new evolutionary algorithm that evolves computer programs. The daily hydrometeorological data of three rainfall stations and one streamflow station for Juniata River Basin in Pennsylvania state of USA are taken into consideration in the model development. Statistical parameters such as average, standard deviation, coefficient of variation, skewness, minimum and maximum values, as well as criteria such as mean square error (MSE) and determination coefficient (2) are used to measure the performance of the models. The results indicate that the proposed genetic programming (GP) formulation performs quite well compared to results obtained by ANNs and is quite practical for use. It is concluded from the results that GEP can be proposed as an alternative to ANN models.

  4. Revisiting Runoff Model Calibration: Airborne Snow Observatory Results Allow Improved Modeling Results

    Science.gov (United States)

    McGurk, B. J.; Painter, T. H.

    2014-12-01

    Deterministic snow accumulation and ablation simulation models are widely used by runoff managers throughout the world to predict runoff quantities and timing. Model fitting is typically based on matching modeled runoff volumes and timing with observed flow time series at a few points in the basin. In recent decades, sparse networks of point measurements of the mountain snowpacks have been available to compare with modeled snowpack, but the comparability of results from a snow sensor or course to model polygons of 5 to 50 sq. km is suspect. However, snowpack extent, depth, and derived snow water equivalent have been produced by the NASA/JPL Airborne Snow Observatory (ASO) mission for spring of 20013 and 2014 in the Tuolumne River basin above Hetch Hetchy Reservoir. These high-resolution snowpack data have exposed the weakness in a model calibration based on runoff alone. The U.S. Geological Survey's Precipitation Runoff Modeling System (PRMS) calibration that was based on 30-years of inflow to Hetch Hetchy produces reasonable inflow results, but modeled spatial snowpack location and water quantity diverged significantly from the weekly measurements made by ASO during the two ablation seasons. The reason is that the PRMS model has many flow paths, storages, and water transfer equations, and a calibrated outflow time series can be right for many wrong reasons. The addition of a detailed knowledge of snow extent and water content constrains the model so that it is a better representation of the actual watershed hydrology. The mechanics of recalibrating PRMS to the ASO measurements will be described, and comparisons in observed versus modeled flow for both a small subbasin and the entire Hetch Hetchy basin will be shown. The recalibrated model provided a bitter fit to the snowmelt recession, a key factor for water managers as they balance declining inflows with demand for power generation and ecosystem releases during the final months of snow melt runoff.

  5. The concept of runoff elements as a basis of scale-free approach to runoff formation modelling - the experience of the model "Hydrograph" development and implementation

    Science.gov (United States)

    Vinogradov, Yu. B.; Semenova, O.

    2009-04-01

    The concept of runoff elements used in proposed model as a base for calculating routine describing slope runoff transformation gives the opportunity to avoid the scale problem in hydrological modelling which, to our opinion, mainly refers to mathematical approaches (the framework of Navier-Stokes equations) widely used for description of water movement within the basin. River basin is a system of elementary watersheds of surface and underground ones of various layers. The topography of river basin surface conditionally can be presented by a system of the inclined surfaces each of them being an elementary slope. Within a surface elementary slope water flowing down is realized over non-channel rill system and within the underground elementary slope - over the underground drainage system. The elementary slopes and watersheds in their turn consist of a system of runoff elements - limited by micro-divides areas of the surface and underground elementary slopes and watersheds exposed with their open part to the slope non-channel or underground drainage system. Runoff elements are not the kind of idealization but they can be easily identified with the natural formations. Surface runoff elements depending on natural conditions but mainly on inclination can be measured from shares and ones up to tens of thousand square meters. Underground runoff elements can be much greater. For each runoff element there is a balance ratio (1) There is the unique nonlinear relation between W and outflow dischargeR: (2) Then, the corresponding equation of the outflow hydrograph from runoff elements of a given layer is the following: (3) Here R0 is the initial value of runoff R and S is the runoff rate (m3s-1); Δt is the computational time interval (sec) during which S is constant; a,b - hydraulic coefficients (which determine the conditions of outflow) with dimension m-3 and m3 s-1. In the general case, we assume that the number of runoff elements is proportional to the basin area F (m2

  6. Rainfall-runoff modeling for storm events in a coastal forest catchment using neural networks

    Institute of Scientific and Technical Information of China (English)

    WANG Yi; HE Bin

    2008-01-01

    The process of transformation of rainfall into runoff over a catchment is very complex and highly nonlinear and exhibits both temporal and spatial variabilities. In this article, a rainfall-runoff model using the artificial neural networks (ANN) is proposed for simulating the runoff in storm events. The study uses the data from a coastal forest catchmentlocated in Seto Inland Sea, Japan. This article studies the accuracy of the short-term rainfall forecast obtained by ANN time-series analysis techniques and using antecedent rainfall depths and stream flow as the input information. The verification results from the proposed model indicate that the approach of ANN rainfall-runoff model presented in this paper shows a reasonable agreement in rainfall-runoff modeling with high accuracy.

  7. Uncertainty in Predicted Neighborhood-Scale Green Stormwater Infrastructure Performance Informed by field monitoring of Hydrologic Abstractions

    Science.gov (United States)

    Smalls-Mantey, L.; Jeffers, S.; Montalto, F. A.

    2013-12-01

    Human alterations to the environment provide infrastructure for housing and transportation but have drastically changed local hydrology. Excess stormwater runoff from impervious surfaces generates erosion, overburdens sewer infrastructure, and can pollute receiving bodies. Increased attention to green stormwater management controls is based on the premise that some of these issues can be mitigated by capturing or slowing the flow of stormwater. However, our ability to predict actual green infrastructure facility performance using physical or statistical methods needs additional validation, and efforts to incorporate green infrastructure controls into hydrologic models are still in their infancy stages. We use more than three years of field monitoring data to derive facility specific probability density functions characterizing the hydrologic abstractions provided by a stormwater treatment wetland, streetside bioretention facility, and a green roof. The monitoring results are normalized by impervious area treated, and incorporated into a neighborhood-scale agent model allowing probabilistic comparisons of the stormwater capture outcomes associated with alternative urban greening scenarios. Specifically, we compare the uncertainty introduced into the model by facility performance (as represented by the variability in the abstraction), to that introduced by both precipitation variability, and spatial patterns of emergence of different types of green infrastructure. The modeling results are used to update a discussion about the potential effectiveness of urban green infrastructure implementation plans.

  8. Hybrid wavelet-support vector machine approach for modelling rainfall-runoff process.

    Science.gov (United States)

    Komasi, Mehdi; Sharghi, Soroush

    2016-01-01

    Because of the importance of water resources management, the need for accurate modeling of the rainfall-runoff process has rapidly grown in the past decades. Recently, the support vector machine (SVM) approach has been used by hydrologists for rainfall-runoff modeling and the other fields of hydrology. Similar to the other artificial intelligence models, such as artificial neural network (ANN) and adaptive neural fuzzy inference system, the SVM model is based on the autoregressive properties. In this paper, the wavelet analysis was linked to the SVM model concept for modeling the rainfall-runoff process of Aghchai and Eel River watersheds. In this way, the main time series of two variables, rainfall and runoff, were decomposed to multiple frequent time series by wavelet theory; then, these time series were imposed as input data on the SVM model in order to predict the runoff discharge one day ahead. The obtained results show that the wavelet SVM model can predict both short- and long-term runoff discharges by considering the seasonality effects. Also, the proposed hybrid model is relatively more appropriate than classical autoregressive ones such as ANN and SVM because it uses the multi-scale time series of rainfall and runoff data in the modeling process.

  9. Comparing projections of future changes in runoff from hydrological and biome models in ISI-MIP

    NARCIS (Netherlands)

    Davie, J.C.S.; Falloon, P.D.; Kahana, R.; Dankers, R.; Betts, R.; Portmann, F.T.; Wisser, D.; Clark, D.B.; Ito, A.; Masaki, Y.; Nishina, K.; Fekete, B.; Tessler, Z.; Wada, Y.; Liu, X.; Tang, Q.; Hagemann, S.; Stacke, T.; Pavlick, R.; Schaphoff, S.; Gosling, S.N.; Franssen, W.H.P.; Arnell, N.

    2013-01-01

    Future changes in runoff can have important implications for water resources and flooding. In this study, runoff projections from ISI-MIP (Inter-sectoral Impact Model Inter-comparison Project) simulations forced with HadGEM2-ES bias-corrected climate data under the Representative Concentration Pathw

  10. Comparing projections of future changes in runoff from hydrological and biome models in ISI-MIP

    NARCIS (Netherlands)

    Davie, J. C. S.; Falloon, P. D.; Kahana, R.; Dankers, R.; Betts, R.; Portmann, F. T.; Wisser, D.; Clark, D. B.; Ito, A.; Masaki, Y.; Nishina, K.; Fekete, B.; Tessler, Z.; Wada, Y.; Liu, X.; Tang, Q.; Hagemann, S.; Stacke, T.; Pavlick, R.; Schaphoff, S.; Gosling, S. N.; Franssen, W.; Arnell, N.

    2013-01-01

    Future changes in runoff can have important implications for water resources and flooding. In this study, runoff projections from ISI-MIP (Inter-sectoral Impact Model Intercomparison Project) simulations forced with HadGEM2-ES bias-corrected climate data under the Representative Concentration Pathwa

  11. Scale effects in Hortonian surface runoff on agricultural slopes in West Africa: Field data and models

    NARCIS (Netherlands)

    Giesen, van de N.; Stomph, T.J.; Ajayi, A.E.; Bagayoko, F.

    2011-01-01

    This article provides an overview of both experimental and modeling research carried out over the past 15 years by the authors addressing scaling effects in Hortonian surface runoff. Hortonian surface runoff occurs when rainfall intensity exceeds infiltration capacity of the soil. At three sites in

  12. Neural network emulation of a rainfall-runoff model

    Directory of Open Access Journals (Sweden)

    R. J. Abrahart

    2007-02-01

    Full Text Available The potential of an artificial neural network to perform simple non-linear hydrological transformations is examined. Four neural network models were developed to emulate different facets of a recognised non-linear hydrological transformation equation that possessed a small number of variables and contained no temporal component. The modeling process was based on a set of uniform random distributions. The cloning operation facilitated a direct comparison with the exact equation-based relationship. It also provided broader information about the power of a neural network to emulate existing equations and model non-linear relationships. Several comparisons with least squares multiple linear regression were performed. The first experiment involved a direct emulation of the Xinanjiang Rainfall-Runoff Model. The next two experiments were designed to assess the competencies of two neural solutions that were developed on a reduced number of inputs. This involved the omission and conflation of previous inputs. The final experiment used derived variables to model intrinsic but otherwise concealed internal relationships that are of hydrological interest. Two recent studies have suggested that neural solutions offer no worthwhile improvements in comparison to traditional weighted linear transfer functions for capturing the non-linear nature of hydrological relationships. Yet such fundamental properties are intrinsic aspects of catchment processes that cannot be excluded or ignored. The results from the four experiments that are reported in this paper are used to challenge the interpretations from these two earlier studies and thus further the debate with regards to the appropriateness of neural networks for hydrological modelling.

  13. Moving stormwater P management upstream (Invited)

    Science.gov (United States)

    Baker, L. A.; Hobbie, S. E.; Finlay, J. C.; Kalinosky, P.; Janke, B.

    2013-12-01

    Reducing stormwater phosphorus loading using current approaches, which focus on treatment at the end of the pipe, is unlikely to reduce P loads enough to restore nutrient-impaired urban lakes. An indication of this is that of the nearly 150 nutrient impaired lakes in the Twin Cities region, only one has been restored. We hypothesize that substantial reduction of eutrophication will require reductions of P inputs upstream from storm drains. Developing source reduction strategies will required a shift in thinking about system boundaries, moving upstream from the storm drain to the curb, and from the curb to the watershed. Our Prior Lake Street Sweeping Project, a 2-year study of enhanced street sweeping, will be used to illustrate the idea of moving the system boundary to the curb. This study showed that P load recovery from sweeping increases with both sweeping frequency and overhead tree canopy cover. For high canopy streets, coarse organic material (tree leaves; seed pods, etc.) comprised 42% of swept material. We estimate that P inputs from trees may be half of measured storm P yields in 8 urban catchments in St. Paul, MN. Moreover, the cost of removing P during autumn was often 1000/lb P for stormwater ponds. We can also move further upstream, to the watershed boundary. P inputs to urban watersheds that enter lawns include lawn fertilizer, polyphosphates added to water supplies (and hence to lawns via irrigation), and pet food (transformed to pet waste). Minnesota enacted a lawn P fertilizer restriction in 2003, but early reductions in stormwater P loads were modest, probably reflecting reduction in direct wash-off of applied fertilizer. Because urban soils are enriched in P, growing turf has continued to extract available soil P. When turf is mowed, cut grass decomposes, generating P in runoff. As soil P becomes depleted, P concentrations in lawn runoff will gradually decline. Preliminary modeling suggests that substantial reductions in P export from lawns may

  14. Two Conceptual Approaches For The Continuous Time Computation of Infiltration and Surface Runoff In Spatially Distributed Rainfall-runoff Models

    Science.gov (United States)

    Brath, A.; Crosta, G.; Frattini, P.; Montanari, A.; Moretti, G.

    Distributed rainfall-runoff models are often applied for performing hydrological sim- ulations extended to the time span of single flood events, in order to limit the compu- tational effort. The increasing availability of computing powers makes now possible to move towards standard techniques for flood hydrograph estimation based upon the application of continuous simulation distributed models. These allow to perform hy- drological analyses that would be not possible by using lumped models, such as, for instance, the assessment of the effects on river discharges of spatially distributed land- use changes. In order to perform spatially-distributed and continuous time hydrologi- cal simulations, one has to represent the infiltration process at the local scale by using schemes which are capable of simulating the soil water content redistribution during the interstorm periods. To this end, the present study aims at presenting an application of two conceptual schemes, which have been derived by modifying the event-based Green-Ampt and Curve Number infiltration models. The proposed approaches have been embedded in a spatially distributed, DEM-based, rainfall-runoff model. An ap- plication of the model is presented, that refers to a river basin located in Northern Italy.

  15. Modeling relationship between runoff and soil properties in dry-farming lands, NW Iran

    Directory of Open Access Journals (Sweden)

    A. R. Vaezi

    2010-04-01

    Full Text Available The process of transformation of rainfall into runoff over a catchment is very complex and exhibits both temporal and spatial variability. However, in a semi-arid area this variability is mainly controlled by the physical and chemical properties of the soil surface. Developing an accurate and easily-used model that can appropriately determine the runoff generation value is of strong demand. In this study a simple, an empirically based model developed to explore effect of soil properties on runoff generation. Thirty six dry-farming lands under follow conditions in a semi-arid agricultural zone in Hashtroud, NW Iran were considered to installation of runoff plots. Runoff volume was measured at down part of standard plots under natural rainfall events from March 2005 to March 2007. Results indicated that soils were mainly clay loam having 36.7% sand, 31.6% silt and 32.0% clay, and calcareous with about 13% lime. During a 2-year period, 41 natural rainfall events produced surface runoff at the plots. Runoff was negatively (R2=0.61, p<0.001 affected by soil permeability. Runoff also significantly correlated with sand, coarse sand, silt, organic matter, lime, and aggregate stability, while its relationship with very fine sand, clay, gravel and potassium was not significant. Regression analysis showed that runoff was considerably (p<0.001, R2=0.64 related to coarse sand, organic matter and lime. Lime like to coarse sand and organic matter positively correlated with soil permeability and consequently decreased runoff. This result revealed that, lime is one of the most important factors controlling runoff in soils of the semi-arid regions.

  16. A geomorphology-based ANFIS model for multi-station modeling of rainfall-runoff process

    Science.gov (United States)

    Nourani, Vahid; Komasi, Mehdi

    2013-05-01

    This paper demonstrates the potential use of Artificial Intelligence (AI) techniques for predicting daily runoff at multiple gauging stations. Uncertainty and complexity of the rainfall-runoff process due to its variability in space and time in one hand and lack of historical data on the other hand, cause difficulties in the spatiotemporal modeling of the process. In this paper, an Integrated Geomorphological Adaptive Neuro-Fuzzy Inference System (IGANFIS) model conjugated with C-means clustering algorithm was used for rainfall-runoff modeling at multiple stations of the Eel River watershed, California. The proposed model could be used for predicting runoff in the stations with lack of data or any sub-basin within the watershed because of employing the spatial and temporal variables of the sub-basins as the model inputs. This ability of the integrated model for spatiotemporal modeling of the process was examined through the cross validation technique for a station. In this way, different ANFIS structures were trained using Sugeno algorithm in order to estimate daily discharge values at different stations. In order to improve the model efficiency, the input data were then classified into some clusters by the means of fuzzy C-means (FCMs) method. The goodness-of-fit measures support the gainful use of the IGANFIS and FCM methods in spatiotemporal modeling of hydrological processes.

  17. The Wageningen Lowland Runoff Simulator (WALRUS): development of a novel parametric rainfall-runoff model using field experience

    Science.gov (United States)

    Brauer, Claudia; Torfs, Paul; Teuling, Ryan; Uijlenhoet, Remko

    2014-05-01

    We present the Wageningen Lowland Runoff Simulator (WALRUS), a novel rainfall-runoff model to fill the gap between complex, spatially distributed models for lowland catchments and simple, parametric models for mountainous catchments. From observations and experience from two Dutch field sites (the Hupsel Brook catchment and the Cabauw polder), we identified key processes for runoff generation in lowland catchments and important feedbacks between components in the hydrological system. We used this knowledge to design a parametric model which can be used all over the world in both freely draining lowland catchments and polders with controlled water levels. While using only four parameters which require calibration, WALRUS explicitly accounts for processes that are important in lowland areas: (1) Groundwater-unsaturated zone coupling: WALRUS contains one soil reservoir, which is divided effectively by the (dynamic) groundwater table into a groundwater zone and a vadose zone. The condition of this soil reservoir is described by two strongly dependent variables: the groundwater depth and the storage deficit (the effective thickness of empty pores). This implementation enables capillary rise when the top soil has dried through evapotranspiration. (2) Wetness-dependent flowroutes: The storage deficit determines the division of rain water between the soil reservoir (slow routes: infiltration, percolation and groundwater flow) and a quickflow reservoir (quick routes: drainpipe, macropore and overland flow). (3) Groundwater-surface water feedbacks: Surface water forms an explicit part of the model structure. Drainage depends on the difference between surface water level and groundwater level (rather than groundwater level alone), allowing for feedbacks and infiltration of surface water into the soil. (4) Seepage and surface water supply: Groundwater seepage and surface water supply or extraction (pumping) are added to or subtracted from the soil or surface water reservoir

  18. Century‐scale variability in global annual runoff examined using a water balance model

    National Research Council Canada - National Science Library

    McCabe, Gregory J; Wolock, David M

    2011-01-01

    A monthly water balance model (WB model) is used with CRUTS2.1 monthly temperature and precipitation data to generate time series of monthly runoff for all land areas of the globe for the period 1905 through 2002...

  19. [Local sensitivity and its stationarity analysis for urban rainfall runoff modelling].

    Science.gov (United States)

    Lin, Jie; Huang, Jin-Liang; Du, Peng-Fei; Tu, Zhen-Shun; Li, Qing-Sheng

    2010-09-01

    Sensitivity analysis of urban-runoff simulation is a crucial procedure for parameter identification and uncertainty analysis. Local sensitivity analysis using Morris screening method was carried out for urban rainfall runoff modelling based on Storm Water Management Model (SWMM). The results showed that Area, % Imperv and Dstore-Imperv are the most sensitive parameters for both total runoff volume and peak flow. Concerning total runoff volume, the sensitive indices of Area, % Imperv and Dstore-Imperv were 0.46-1.0, 0.61-1.0, -0.050(-) - 5.9, respectively; while with respect to peak runoff, they were 0.48-0.89, 0.59-0.83, 0(-) -9.6, respectively. In comparison, the most sensitive indices (Morris) for all parameters with regard to total runoff volume and peak flow appeared in the rainfall event with least rainfall; and less sensitive indices happened in the rainfall events with heavier rainfall. Furthermore, there is considerable variability in sensitive indices for each rainfall event. % Zero-Imperv's coefficient variations have the largest values among all parameters for total runoff volume and peak flow, namely 221.24% and 228.10%. On the contrary, the coefficient variations of conductivity among all parameters for both total runoff volume and peak flow are the smallest, namely 0.

  20. Modeling relationship between runoff and soil properties in dry-farming lands, NW Iran

    Science.gov (United States)

    Vaezi, A. R.; Bahrami, H. A.; Sadeghi, S. H. R.; Mahdian, M. H.

    2010-04-01

    The process of transformation of rainfall into runoff over a catchment is very complex and exhibits both temporal and spatial variability. However, in a semi-arid area this variability is mainly controlled by the physical and chemical properties of the soil surface. Developing an accurate and easily-used model that can appropriately determine the runoff generation value is of strong demand. In this study a simple, an empirically based model developed to explore effect of soil properties on runoff generation. Thirty six dry-farming lands under follow conditions in a semi-arid agricultural zone in Hashtroud, NW Iran were considered to installation of runoff plots. Runoff volume was measured at down part of standard plots under natural rainfall events from March 2005 to March 2007. Results indicated that soils were mainly clay loam having 36.7% sand, 31.6% silt and 32.0% clay, and calcareous with about 13% lime. During a 2-year period, 41 natural rainfall events produced surface runoff at the plots. Runoff was negatively (R2=0.61, pfactors controlling runoff in soils of the semi-arid regions.

  1. Mid- and long-term runoff predictions by an improved phase-space reconstruction model.

    Science.gov (United States)

    Hong, Mei; Wang, Dong; Wang, Yuankun; Zeng, Xiankui; Ge, Shanshan; Yan, Hengqian; Singh, Vijay P

    2016-07-01

    In recent years, the phase-space reconstruction method has usually been used for mid- and long-term runoff predictions. However, the traditional phase-space reconstruction method is still needs to be improved. Using the genetic algorithm to improve the phase-space reconstruction method, a new nonlinear model of monthly runoff is constructed. The new model does not rely heavily on embedding dimensions. Recognizing that the rainfall-runoff process is complex, affected by a number of factors, more variables (e.g. temperature and rainfall) are incorporated in the model. In order to detect the possible presence of chaos in the runoff dynamics, chaotic characteristics of the model are also analyzed, which shows the model can represent the nonlinear and chaotic characteristics of the runoff. The model is tested for its forecasting performance in four types of experiments using data from six hydrological stations on the Yellow River and the Yangtze River. Results show that the medium-and long-term runoff is satisfactorily forecasted at the hydrological stations. Not only is the forecasting trend accurate, but also the mean absolute percentage error is no more than 15%. Moreover, the forecast results of wet years and dry years are both good, which means that the improved model can overcome the traditional ''wet years and dry years predictability barrier,'' to some extent. The model forecasts for different regions are all good, showing the universality of the approach. Compared with selected conceptual and empirical methods, the model exhibits greater reliability and stability in the long-term runoff prediction. Our study provides a new thinking for research on the association between the monthly runoff and other hydrological factors, and also provides a new method for the prediction of the monthly runoff.

  2. Consequential environmental and economic life cycle assessment of green and gray stormwater infrastructures for combined sewer systems.

    Science.gov (United States)

    Wang, Ranran; Eckelman, Matthew J; Zimmerman, Julie B

    2013-10-01

    A consequential life cycle assessment (LCA) is conducted to evaluate the trade-offs between water quality improvements and the incremental climate, resource, and economic costs of implementing green (bioretention basin, green roof, and permeable pavement) versus gray (municipal separate stormwater sewer systems, MS4) alternatives of stormwater infrastructure expansions against a baseline combined sewer system with combined sewer overflows in a typical Northeast US watershed for typical, dry, and wet years. Results show that bioretention basins can achieve water quality improvement goals (e.g., mitigating freshwater eutrophication) for the least climate and economic costs of 61 kg CO2 eq. and $98 per kg P eq. reduction, respectively. MS4 demonstrates the minimum life cycle fossil energy use of 42 kg oil eq. per kg P eq. reduction. When integrated with the expansion in stormwater infrastructure, implementation of advanced wastewater treatment processes can further reduce the impact of stormwater runoff on aquatic environment at a minimal environmental cost (77 kg CO2 eq. per kg P eq. reduction), which provides support and valuable insights for the further development of integrated management of stormwater and wastewater. The consideration of critical model parameters (i.e., precipitation intensity, land imperviousness, and infrastructure life expectancy) highlighted the importance and implications of varying local conditions and infrastructure characteristics on the costs and benefits of stormwater management. Of particular note is that the impact of MS4 on the local aquatic environment is highly dependent on local runoff quality indicating that a combined system of green infrastructure prior to MS4 potentially provides a more cost-effective improvement to local water quality.

  3. Hydrological daily rainfall-runoff simulation with BTOPMC model and comparison with Xin'anjiang model

    Institute of Scientific and Technical Information of China (English)

    Hong-jun BAO; Li-li WANG; Zhi-jia LI; Lin-na ZHAO; Guo-ping ZHANG

    2010-01-01

    A grid-based distributed hydrological model, the Block-wise use of TOPMODEL (BTOPMC), which was developed from the original TOPMODEL, was used for hydrological daily rainfall-runoff simulation. In the BTOPMC model, the runoff is explicitly calculated on a cell-by-cell basis, and the Muskingum-Cunge flow concentration method is used. In order to test the model's applicability, the BTOPMC model and the Xin'anjiang model were applied to the simulation of a humid watershed and a semi-humid to semi-arid watershed in China. The model parameters were optimized with the Shuffle Complex Evolution (SCE-UA) method. Results show that both models can effectively simulate the daily hydrograph in humid watersheds, but that the BTOPMC model performs poorly in semi-humid to semi-arid watersheds. The excess-infiltration mechanism should be incorporated into the BTOPMC model to broaden the model's applicability.

  4. Modeling on runoff concentration caused by rainfall on hillslopes and application in Maoping slope

    Institute of Scientific and Technical Information of China (English)

    LIU Qingquan; LI Jiachun

    2006-01-01

    Based on the fact that the concentration flowlines of overland flow depend on the surface landform of hillslope, a kinematic wave model was developed for simulating runoff generation and flow concentration caused by rainfall on hillslopes. The model-simulated results agree well with the experimental observations. Applying the model to the practical case of Maoping slope, we obtained the characteristics of runoff generation and infiltration on the slope. Especially, the simulated results adequately reflected the confluent pattern of surface runoff, which offers a scientific foundation for designing the drainage engineering on the Maoping slope.

  5. BMPs in urban stormwater management in Denmark and Sweden

    DEFF Research Database (Denmark)

    Mikkelsen, Peter Steen; Viklander, M.; Linde, Jens Jørgen

    2002-01-01

    Best Management Practices (BMPs) for control of stormwater runoff include structural elemts (structural BMPs) that can be applied on the local scale (e.g. infiltration), the drainage catchment scale (e.g. ponds and treatment, or wetlands) and the receiving water scale (e.g. retrofitting of river ....... A review of recent experiences with selected stormwater BMPs in Denmark and Sweden is presented and discussed with respect to the current issues related to legislation and the forces driving future development in stormwater management.......Best Management Practices (BMPs) for control of stormwater runoff include structural elemts (structural BMPs) that can be applied on the local scale (e.g. infiltration), the drainage catchment scale (e.g. ponds and treatment, or wetlands) and the receiving water scale (e.g. retrofitting of river...

  6. Modeling urban storm rainfall runoff from diverse underlying surfaces and application for control design in Beijing.

    Science.gov (United States)

    Ouyang, Wei; Guo, Bobo; Hao, Fanghua; Huang, Haobo; Li, Junqi; Gong, Yongwei

    2012-12-30

    Managing storm rainfall runoff is paramount in semi-arid regions with urban development. In Beijing, pollution prevention in urban storm runoff and storm water utilization has been identified as the primary strategy for urban water management. In this paper, we sampled runoff during storm rainfall events and analyzed the concentration of chemical oxygen demand (COD), total suspended solids (TSS) and total phosphorus (TP) in the runoff. Furthermore, the first flush effect of storm rainfall from diverse underlying surfaces was also analyzed. With the Storm Water Management Model (SWMM), the different impervious rates of underlying surfaces during the storm runoff process were expressed. The removal rates of three typical pollutants and their interactions with precipitation and underlying surfaces were identified. From these rates, the scenarios regarding the urban storm runoff pollution loading from different designs of underlying previous rates were assessed with the SWMM. First flush effect analysis showed that the first 20% of the storm runoff should be discarded, which can help in utilizing the storm water resource. The results of this study suggest that the SWMM can express in detail the storm water pollution patterns from diverse underlying surfaces in Beijing, which significantly affected water quality. The scenario analysis demonstrated that impervious rate adjustment has the potential to reduce runoff peak and decrease pollution loading.

  7. Accounting for the Impact of Impermeable Soil Layers on Pesticide Runoff and Leaching in a Landscape Vulnerability Model

    Science.gov (United States)

    A regional-scale model that estimates landscape vulnerability of pesticide leaching and runoff (solution and particle adsorbed) underestimated runoff vulnerability and overestimated leaching vulnerability compared to measured data when applied to a gently rolling landscape in northeast Missouri. Man...

  8. Constraints of artificial neural networks for rainfall-runoff modelling: trade-offs in hydrological state representation and model evaluation

    NARCIS (Netherlands)

    Vos, de N.J.; Rientjes, T.H.M.

    2005-01-01

    The application of Artificial Neural Networks (ANNs) in rainfall-runoff modelling needs to be researched more extensively in order to appreciate and fulfil the potential of this modelling approach. This paper reports on the application of multi-layer feedforward ANNs for rainfall-runoff modelling of

  9. Modelling heterogeneous flow in the vadoze zone underneath a stormwater infiltration basin

    Science.gov (United States)

    Winiarski, T.; Lassabatere, L.; Angulo-Jaramillo, R.; Goutaland, D.

    2011-12-01

    Infiltration basins are part of the best management practices. They are aimed at infiltrating stormwater to prevent additional collection and treatment through rainwater systems. In the suburbs of Lyon (France), many of these infiltration basins were built over fluvio-glacial deposit. These basins have been the subject of research programs on vadose zone flow and fate of pollutants. This study focuses on the impact of the heterogeneity of the fluvio-glacial deposit on both flow pattern and solute transfer. A proper geological and sedimentological description is first proposed to characterize the efficient water transfer properties of the fluvio-glacial deposit at the work scale (1 ha). The local geological and sedimentological architecture of the deposit and its lithofacies were investigated locally through trenches using both particle size analysis and sedimentological approach. This information was extended to the whole work by combining several geophysical techniques, i.e. GPR, electric resistivity and seismic refraction tomography. Then water infiltration experiments were performed on each lithofacies to derive the hydrodynamic properties through BEST algorithm (Beerkan estimation of Soil Transfer properties), leading to the corresponding hydrofacies. In addition, soil-column experiments were performed to estimate hydrodispersive parameters (tracer injection) and the geochemical properties of lithofacies (injection of model pollutants). All these data were implemented into Hydrus to model flow and solute transfer through a 2D soil profile with a precise description of the hydrofacies at the basin scale (flow domain 14x2 m2). The results are highly relevant because they emphasize different types of preferential flow due to either the presence of capillary barriers, drainage layers or pipe flow, which may be responsible for the enhancement of pollutant transfer. In particular, they show that sand lenses may play an important role whereas unconnected gravels may

  10. Evaluation of Three Models for Simulating Pesticide Runoff from Irrigated Agricultural Fields.

    Science.gov (United States)

    Zhang, Xuyang; Goh, Kean S

    2015-11-01

    Three models were evaluated for their accuracy in simulating pesticide runoff at the edge of agricultural fields: Pesticide Root Zone Model (PRZM), Root Zone Water Quality Model (RZWQM), and OpusCZ. Modeling results on runoff volume, sediment erosion, and pesticide loss were compared with measurements taken from field studies. Models were also compared on their theoretical foundations and ease of use. For runoff events generated by sprinkler irrigation and rainfall, all models performed equally well with small errors in simulating water, sediment, and pesticide runoff. The mean absolute percentage errors (MAPEs) were between 3 and 161%. For flood irrigation, OpusCZ simulated runoff and pesticide mass with the highest accuracy, followed by RZWQM and PRZM, likely owning to its unique hydrological algorithm for runoff simulations during flood irrigation. Simulation results from cold model runs by OpusCZ and RZWQM using measured values for model inputs matched closely to the observed values. The MAPE ranged from 28 to 384 and 42 to 168% for OpusCZ and RZWQM, respectively. These satisfactory model outputs showed the models' abilities in mimicking reality. Theoretical evaluations indicated that OpusCZ and RZWQM use mechanistic approaches for hydrology simulation, output data on a subdaily time-step, and were able to simulate management practices and subsurface flow via tile drainage. In contrast, PRZM operates at daily time-step and simulates surface runoff using the USDA Soil Conservation Service's curve number method. Among the three models, OpusCZ and RZWQM were suitable for simulating pesticide runoff in semiarid areas where agriculture is heavily dependent on irrigation.

  11. Rainfall-Runoff Modelling using Modified NRCS-CN,RS and GIS -A Case Study

    Directory of Open Access Journals (Sweden)

    P.Sundara Kumar

    2016-03-01

    Full Text Available Study of rainfall and runoff for any area and modeling it, is one of the important aspects for planning and development of water resources. The development of water resources and its effective management plays a vital role in development of any country more particularly in India, which is an agricultural based economy. Hence it is intended to develop a model of Rainfall and runoff to a river basin and also apply the methodology to Sarada River Basin which has drainage area of 1252.99 Sq.km. The basin is situated in Vishakhapatnam district of Andhra Pradesh, India. The rainfall and runoff data has been collected from the gauging stations of the basin apart from rainfall data from nearby stations. MNRCS-CN method has been adopted to calculate runoff. Various hydrological parameters like soil information, rainfall, land use and land cover (LU/LC were considered to use in MNRCS-CN method. The depth of runoff has been computed for different land use patterns using, IRS-P4- LISS IV data for the study area. Based on the analysis, land use/land cover pattern of Sarada River Basin has been prepared. The land use/land cover patterns were also visually interpreted and digitized using ERDAS IMAGINE software. The raster data was processed in ERDAS and geo-referenced and various maps viz. LU/LC maps, drainage map, contour map, DEM (Digital elevation model have been generated apart from rainfall potential map using GIS tool. The estimated runoff using MNRCS-CN model has been simulated and compared with that of actual runoff. The performance of the model is found to be good for the data considered. The coefficient of determination R2 value for the observed runoff and that of the computed runoff is found to be more than 0.72 for the selected watershed basin

  12. 1D Runoff-runon stochastic model in the light of queueing theory : heterogeneity and connectivity

    Science.gov (United States)

    Harel, M.-A.; Mouche, E.; Ledoux, E.

    2012-04-01

    identical to the waiting time equation in a single server queue. Thanks to this theory, it is possible to accurately describe some outputs of our numerical model, notably the runoff repartition over the slope for uncorrelated exponential infiltrability distributions. Alternative formulations for the connectivity function of Allard (which cannot be predicted theoretically to our knowledge) are discussed with regard to predictability, efficiency in computation and qualification of the "near-connectedness" state of the system.

  13. Real Time Updating in Distributed Urban Rainfall Runoff Modelling

    DEFF Research Database (Denmark)

    Borup, Morten; Madsen, Henrik

    When it rains on urban areas the rainfall runoff is transported out of the city via the drainage system. Frequently, the drainage system cannot handle all the rain water, which results in problems like flooding or overflows into natural water bodies. To reduce these problems the systems...

  14. Generation of Natural Runoff Monthly Series at Ungauged Sites Using a Regional Regressive Model

    Directory of Open Access Journals (Sweden)

    Dario Pumo

    2016-05-01

    Full Text Available Many hydrologic applications require reliable estimates of runoff in river basins to face the widespread lack of data, both in time and in space. A regional method for the reconstruction of monthly runoff series is here developed and applied to Sicily (Italy. A simple modeling structure is adopted, consisting of a regression-based rainfall–runoff model with four model parameters, calibrated through a two-step procedure. Monthly runoff estimates are based on precipitation, temperature, and exploiting the autocorrelation with runoff at the previous month. Model parameters are assessed by specific regional equations as a function of easily measurable physical and climate basin descriptors. The first calibration step is aimed at the identification of a set of parameters optimizing model performances at the level of single basin. Such “optimal” sets are used at the second step, part of a regional regression analysis, to establish the regional equations for model parameters assessment as a function of basin attributes. All the gauged watersheds across the region have been analyzed, selecting 53 basins for model calibration and using the other six basins exclusively for validation. Performances, quantitatively evaluated by different statistical indexes, demonstrate relevant model ability in reproducing the observed hydrological time-series at both the monthly and coarser time resolutions. The methodology, which is easily transferable to other arid and semi-arid areas, provides a reliable tool for filling/reconstructing runoff time series at any gauged or ungauged basin of a region.

  15. Analysis of an Urban Stormwater Bioretention Management Practice in Prince William County, Virginia

    OpenAIRE

    Angelo, Suzanne

    2005-01-01

    The performance of an urban stormwater bioretention management practice in the Kingsbrooke Subdivision of Prince William County, Virginia was examined over a one-year period. Bioretention is a relatively new urban stormwater best management practice (BMP) intended to mimic the pollutant-removal characteristics of an upland forest habitat. Typical bioretention areas utilize shallow ponding and highly-infiltrative sandy soils to treat the stormwater runoff from small commercial or ...

  16. Inverse modeling of hydrologic parameters using surface flux and runoff observations in the Community Land Model

    Directory of Open Access Journals (Sweden)

    Y. Sun

    2013-04-01

    Full Text Available This study demonstrates the possibility of inverting hydrologic parameters using surface flux and runoff observations in version 4 of the Community Land Model (CLM4. Previous studies showed that surface flux and runoff calculations are sensitive to major hydrologic parameters in CLM4 over different watersheds, and illustrated the necessity and possibility of parameter calibration. Two inversion strategies, the deterministic least-square fitting and stochastic Markov-Chain Monte-Carlo (MCMC Bayesian inversion approaches, are evaluated by applying them to CLM4 at selected sites. The unknowns to be estimated include surface and subsurface runoff generation parameters and vadose zone soil water parameters. We find that using model parameters calibrated by the least-square fitting provides little improvements in the model simulations but the sampling-based stochastic inversion approaches are consistent – as more information comes in, the predictive intervals of the calibrated parameters become narrower and the misfits between the calculated and observed responses decrease. In general, parameters that are identified to be significant through sensitivity analyses and statistical tests are better calibrated than those with weak or nonlinear impacts on flux or runoff observations. Temporal resolution of observations has larger impacts on the results of inverse modeling using heat flux data than runoff data. Soil and vegetation cover have important impacts on parameter sensitivities, leading to different patterns of posterior distributions of parameters at different sites. Overall, the MCMC-Bayesian inversion approach effectively and reliably improves the simulation of CLM under different climates and environmental conditions. Bayesian model averaging of the posterior estimates with different reference acceptance probabilities can smooth the posterior distribution and provide more reliable parameter estimates, but at the expense of wider uncertainty

  17. Runoff modelling in glacierized Central Asian catchments for present-day and future climate

    OpenAIRE

    Hagg, Wilfried; Braun, L. N.; Weber, M.; Becht, M.

    2006-01-01

    A conceptual precipitation–runoff model was applied in five glacierized catchments in Central Asia. The model, which was first developed and applied in the Alps, works on a daily time step and yields good results in the more continental climate of the Tien Shan mountains for present-day climate conditions. Runoff scenarios for different climates (doubling of CO2) and glacierization conditions predict an increased flood risk as a first stage and a more complex picture after a complete glacier ...

  18. The hydrologic response of urban catchments to distributed green stormwater infrastructure

    Science.gov (United States)

    Obeid, N.; Cai, X.; Schmidt, A.; Werth, C. J.

    2013-12-01

    Proliferation of impervious surfaces in urban watersheds is a serious problem resulting in an increased risk of flooding frequency and magnitude and combined sewer overflows (CSOs). In many urban areas, green roofs are increasingly being built to minimize the impact of increased stormwater runoff, adding more complexity to the urban hydrology. Studies to assess the performance of green roofs at the watershed scale typically lack description of the physical mechanisms underlying flow in green roofs and use statistical analysis of runoff collected at the point scale and scale it up uniformly and linearly in space and time. Such simplifications are not necessarily representative of realistic conditions since green roof performance may be nonlinear. A Hydrus-1D model for an extensive green roof was calibrated and validated using continuous series of high resolution data. The model captures the properties of the engineered soil matrix and inter-event processes (i.e., drying and evapotranspiration). The model was incorporated into a stochastic watershed model, the Illinois Urban Hydrologic Model (IUHM), to assess the impact of green roofs on urban hydrology at different spatial and temporal scales. The model allows us to examine the impact of different sizes, numbers, and distributions of green roofs in the watershed and to test if a threshold exists below which the effect of green roofs at the watershed scale is not statistically significant, given the heterogeneity of hydrology and rainfall. Preliminary results show that green roofs are capable of retaining 18 - 70% of stormwater volume, reducing the peak runoff rate by 70 - 95% and delaying the onset of runoff by up to 3 hours at the site scale, depending on the antecedent soil moisture and type of storm. At the watershed scale, the impact of green roofs on total runoff at the outlet varies and depends on the density of roofs, the type of storm and inter-event period. This research contributes to impact assessment of

  19. Environmental impacts of stormwater management and pollutant discharges

    DEFF Research Database (Denmark)

    Brudler, Sarah; Arnbjerg-Nielsen, Karsten; Hauschild, Michael Zwicky

    using life cycle assessment. The inventory for the assessment is based on an extensive literature research, planning documents and expert interviews. Here, we focus on the ecotoxicity impacts: The impact over the whole life cycle of the system, excluding local emissions, is 14 mio comparative toxic...... units (CTUe). This ecotoxicity impact is mainly caused by the emission of metals. Metals are, however, also important pollutants in stormwater runoff. In Copenhagen, the emission of stormwater pollutants from runoff are found to cause additional impacts of 19 mio CTUe when discharged directly...... to freshwater. If the water first infiltrates through soil, the impacts are significantly lower (10 mio CTUe). The stormwater system itself is passive, and mainly causes impacts during construction, while runoff goes through the system constantly over 100 years, which explains the large difference in impacts...

  20. Rainfall Runoff Modelling for Cedar Creek using HEC-HMS model

    Science.gov (United States)

    Pathak, P.; Kalra, A.

    2015-12-01

    Rainfall-runoff modelling studies are carried out for the purpose of basin and river management. Different models have been effectively used to examine relationships between rainfall and runoff. Cedar Creek Watershed Basin, the largest tributary of St. Josephs River, located in northeastern Indiana, was selected as a study area. The HEC-HMS model developed by US Army Corps of Engineers was used for the hydrological modelling. The national elevation and national hydrography data was obtained from United States Geological Survey National Map Viewer and the SSURGO soil data was obtained from United States Department of Agriculture. The watershed received hypothetical uniform rainfall for a duration of 13 hours. The Soil Conservation Service Curve Number and Unit Hydrograph methods were used for simulating surface runoff. The simulation provided hydrological details about the quantity and variability of runoff in the watershed. The runoff for different curve numbers was computed for the same basin and rainfall, and it was found that outflow peaked at an earlier time with a higher value for higher curve numbers than for smaller curve numbers. It was also noticed that the impact on outflow values nearly doubled with an increase of curve number of 10 for each subbasin in the watershed. The results from the current analysis may aid water managers in effectively managing the water resources within the basin. 1 Graduate Student, Department of Civil and Environmental Engineering, Southern Illinois University Carbondale, Carbondale, Illinois, 62901-6603 2 Development Review Division, Clark County Public Works, 500 S. Grand Central Parkway, Las Vegas, NV 89155, USA

  1. Urban stormwater treatment using bioretention

    Science.gov (United States)

    Trowsdale, Sam A.; Simcock, Robyn

    2011-02-01

    SummaryUrban stormwater has negative environmental and ecological effects. Bioretention systems are starting to be used in efforts to mitigate these effects. A bioretention system receiving water from a light industrial catchment and a busy road was designed, built and monitored for changes in soil physics as well as hydrological and hydrochemical efficiency. The soils in the bioretention system were designed to have high metal removal potential and high permeability to compensate for undersized bioretention volume. The inflow hydrograph was a series of sharp peaks with little baseflow, typical of runoff from impervious surfaces. The bioretention system smoothed the hydrograph by reducing peak flow and volume for all 12 events monitored in detail. Overflow occurred in 10 events indicating the increased permeability did not fully compensate for the undersized volume. Runoff was heavily polluted with sediment and heavy metals, in particular zinc. The majority of the zinc, lead and Total Suspended Sediments were removed from the stormwater that flowed through the bioretention system, with TSS and total zinc concentrations reducing by orders of magnitude. Despite high removal efficiency, median concentrations of zinc exiting the bioretention system still exceeded ecosystem health guidelines and the bioretention system was both a source and sink of copper.

  2. Meltwater flux and runoff modeling in the abalation area of jakobshavn Isbrae, West Greenland

    Energy Technology Data Exchange (ETDEWEB)

    Mernild, Sebastian Haugard [Los Alamos National Laboratory; Chylek, Petr [Los Alamos National Laboratory; Liston, Glen [COLORADO STATE UNIV.; Steffen, Konrad [UNIV OF COLORADO

    2009-01-01

    The temporal variability in surface snow and glacier melt flux and runoff were investigated for the ablation area of lakobshavn Isbrae, West Greenland. High-resolution meteorological observations both on and outside the Greenland Ice Sheet (GrIS) were used as model input. Realistic descriptions of snow accumulation, snow and glacier-ice melt, and runoff are essential to understand trends in ice sheet surface properties and processes. SnowModel, a physically based, spatially distributed meteorological and snow-evolution modeling system was used to simulate the temporal variability of lakobshavn Isbrre accumulation and ablation processes for 2000/01-2006/07. Winter snow-depth observations and MODIS satellite-derived summer melt observations were used for model validation of accumulation and ablation. Simulations agreed well with observed values. Simulated annual surface melt varied from as low as 3.83 x 10{sup 9} m{sup 3} (2001/02) to as high as 8.64 x 10{sup 9} m{sup 3} (2004/05). Modeled surface melt occurred at elevations reaching 1,870 m a.s.l. for 2004/05, while the equilibrium line altitude (ELA) fluctuated from 990 to 1,210 m a.s.l. during the simulation period. The SnowModel meltwater retention and refreezing routines considerably reduce the amount of meltwater available as ice sheet runoff; without these routines the lakobshavn surface runoff would be overestimated by an average of 80%. From September/October through May/June no runoff events were simulated. The modeled interannual runoff variability varied from 1.81 x 10{sup 9} m{sup 3} (2001/02) to 5.21 x 10{sup 9} m{sup 3} (2004/05), yielding a cumulative runoff at the Jakobshavn glacier terminus of {approx}2.25 m w.eq. to {approx}4.5 m w.eq., respectively. The average modeled lakobshavn runoff of {approx}3.4 km{sup 3} y{sup -1} was merged with previous estimates of Jakobshavn ice discharge to quantify the freshwater flux to Illulissat Icefiord. For both runoff and ice discharge the average trends are

  3. RAINFALL-RUNOFF MODELING IN THE TURKEY RIVER USING NUMERICAL AND REGRESSION METHODS

    Directory of Open Access Journals (Sweden)

    J. Behmanesh

    2015-01-01

    Full Text Available Modeling rainfall-runoff relationships in a watershed have an important role in water resources engineering. Researchers have used numerical models for modeling rainfall-runoff process in the watershed because of non-linear nature of rainfall-runoff relationship, vast data requirement and physical models hardness. The main object of this research was to model the rainfall-runoff relationship at the Turkey River in Mississippi. In this research, two numerical models including ANN and ANFIS were used to model the rainfall-runoff process and the best model was chosen. Also, by using SPSS software, the regression equations were developed and then the best equation was selected from regression analysis. The obtained results from the numerical and regression modeling were compared each other. The comparison showed that the model obtained from ANFIS modeling was better than the model obtained from regression modeling. The results also stated that the Turkey river flow rate had a logical relationship with one and two days ago flow rate and one, two and three days ago rainfall values.

  4. RAINFALL-RUNOFF MODELING IN THE TURKEY RIVER USING NUMERICAL AND REGRESSION METHODS

    Directory of Open Access Journals (Sweden)

    J. Behmanesh

    2015-03-01

    Full Text Available Modeling rainfall-runoff relationships in a watershed have an important role in water resources engineering. Researchers have used numerical models for modeling rainfall-runoff process in the watershed because of non-linear nature of rainfall-runoff relationship, vast data requirement and physical models hardness. The main object of this research was to model the rainfall-runoff relationship at the Turkey River in Mississippi. In this research, two numerical models including ANN and ANFIS were used to model the rainfall-runoff process and the best model was chosen. Also, by using SPSS software, the regression equations were developed and then the best equation was selected from regression analysis. The obtained results from the numerical and regression modeling were compared each other. The comparison showed that the model obtained from ANFIS modeling was better than the model obtained from regression modeling. The results also stated that the Turkey river flow rate had a logical relationship with one and two days ago flow rate and one, two and three days ago rainfall values.

  5. Application of SCS Model in Estimation of Runoff from Small Watershed in Loess Plateau of China

    Institute of Scientific and Technical Information of China (English)

    LIU Xianzhao; LI Jiazhu

    2008-01-01

    Soil Conservation Service (SCS) model,developed by U.S.Soil Conservation Service in 1972,has been widely applied in the estimation of runoff from an small watershed.In this paper,based on the remote sensing geo-information data of land use and soil classification all obtained from Landsat images in 1996 and 1997 and conventional data of hydrology and meteorology,the SCS model was investigated for simulating the surface runoff for single rainstorm in Wangdonggou watershed,a typical small watershed in the Loess Plateau,located in Changwu County of Shaanxi Province of China.Wangdonggou watershed was compartmentalized into 28 sub-units according to natural draining division,and the table of curve number (CN) values fitting for Wangdonggou watershed was also presented.During the flood period from 1996 to 1997,the hydrograph of calculated runoff process using the SCS model and the hydrograph of observed runoff process coincided very well in height as well as shape,and the model was of high precision above 75%.It is indicated that the SCS model is legitimate and can be successfully used to simulate the runoff generation and the runoff process of typical small watershed based on the remote sensing geo-information in the Loess Plateau.

  6. The Wageningen Lowland Runoff Simulator (WALRUS): a Novel Open Source Rainfall-Runoff Model for Areas with Shallow Groundwater

    Science.gov (United States)

    Brauer, C.; Teuling, R.; Torfs, P.; Uijlenhoet, R.

    2014-12-01

    Recently, we developed the Wageningen Lowland Runoff Simulator (WALRUS) to fill the gap between complex, spatially distributed models which are often used in lowland regions and simple, parametric models which have mostly been developed for mountainous catchments. This parametric rainfall-runoff model can be used all over the world, both in freely draining lowland catchments and polders with controlled water levels. Here, we present the model implementation and our recent experience in training students and practitioners to use the model. WALRUS has several advantages that facilitate practical application. Firstly, WALRUS is computationally efficient, which allows for operational forecasting and uncertainty estimation by running ensembles. Secondly, the code is set-up such that it can be used by both practitioners and researchers. For direct use by practitioners, defaults are implemented for relations between model variables and for the computation of initial conditions based on discharge only, leaving only four parameters which require calibration. For research purposes, the defaults can easily be changed. Finally, an approach for flexible time steps increases numerical stability and makes model parameter values independent of time step size, which facilitates use of the model with the same parameter set for multi-year water balance studies as well as detailed analyses of individual flood peaks. The open source model code is currently implemented in R and compiled into a package. This package will be made available through the R CRAN server. A small massive open online course (MOOC) is being developed to give students, researchers and practitioners a step-by-step WALRUS-training. This course contains explanations about model elements and its advantages and limitations, as well as hands-on exercises to learn how to use WALRUS. All code, course, literature and examples will be collected on a dedicated website, which can be found via www

  7. Application of spatially varying storage capacity model for runoff parameterization in semi-arid catchment

    Institute of Scientific and Technical Information of China (English)

    Li-liang REN; Gui-zuo WANG; Fang LU; Tian-fang FANG

    2009-01-01

    This paper introduces the method of designation of water storage capacity for each grid cell within a catchment, which considers topography, vegetation and soil synthetically. For the purpose of hydrological process simulation in semi-arid regions, a spatially varying storage capacity (VSC) model was developed based on the spatial distribution of water storage capacity and the vertical hybrid runoff mechanism. To verify the applicability of the VSC model, both the VSC model and a hybrid runoff model were used to simulate daily runoff processes in the catchment upstream of the Dianzi hydrological station from 1973 to 1979. The results showed that the annual average Nash-Sutcliffe coefficient was 0.80 for the VSC model, and only 0.67 for the hybrid runoff model. The higher annual average Nash-Sutcliffe coefficient of the VSC model means that this hydrological model can better simulate daily runoff processes in semi-arid regions. Furthermore, as a distributed hydrological model, the VSC model can be applied in regional water resource management.

  8. Application of spatially varying storage capacity model for runoff parameterization in semi-arid catchment

    Directory of Open Access Journals (Sweden)

    Li-liang REN

    2009-06-01

    Full Text Available This paper introduces the method of designation of water storage capacity for each grid cell within a catchment, which considers topography, vegetation and soil synthetically. For the purpose of hydrological process simulation in semi-arid regions, a spatially varying storage capacity (VSC model was developed based on the spatial distribution of water storage capacity and the vertical hybrid runoff mechanism. To verify the applicability of the VSC model, both the VSC model and a hybrid runoff model were used to simulate daily runoff processes in the catchment upstream of the Dianzi hydrological station from 1973 to 1979. The results showed that the annual average Nash-Sutcliffe coefficient was 0.80 for the VSC model, and only 0.67 for the hybrid runoff model. The higher annual average Nash-Sutcliffe coefficient of the VSC model means that this hydrological model can better simulate daily runoff processes in semi-arid regions. Furthermore, as a distributed hydrological model, the VSC model can be applied in regional water resource management.

  9. Implementation of a Surface Runoff Model with Horton and Dunne Mechanisms into the Regional Climate Model RegCM_NCC

    Institute of Scientific and Technical Information of China (English)

    SHI Xueli; XIE Zhenghui; LIU Yiming; YANG Hongwei

    2007-01-01

    A surface runoff parameterization scheme that dynamically represents both Horton and Dunne runoff generation mechanisms within a model grid cell together with a consideration of the subgrid-scale soil heterogeneity, is implemented into the National Climate Center regional climate model (RegCM_NCC). The effects of the modified surface runoff scheme on RegCM_NCC performance are tested with an abnormal heavy rainfall process which occurred in summer 1998. Simulated results show that the model with the original surface runoff scheme (noted as CTL) basically captures the spatial pattern of precipitation, circulation and land surface variables, but generally overestimates rainfall compared to observations. The model with the new surface runoff scheme (noted as NRM) reasonably reproduces the distribution pattern of various variables and effectively diminishes the excessive precipitation in the CTL. The processes involved in the improvement of NRM-simulated rainfall may be as follows: with the new surface runoff scheme, simulated surface runoff is larger, soil moisture and evaporation (latent heat flux) are decreased, the available water into the atmosphere is decreased; correspondingly, the atmosphere is drier and rainfall is decreased through various processes. Therefore, the implementation of the new runoff scheme into the RegCM_NCC has a significant effect on results at not only the land surface, but also the overlying atmosphere.

  10. Glacier surface mass balance and freshwater runoff modeling for the entire Andes Cordillera

    Science.gov (United States)

    Mernild, Sebastian H.; Liston, Glen E.; Yde, Jacob C.

    2017-04-01

    Glacier surface mass balance (SMB) observations for the Andes Cordillera are limited and, therefore, estimates of the SMB contribution from South America to sea-level rise are highly uncertain. Here, we simulate meteorological, snow, glacier surface, and hydrological runoff conditions and trends for the Andes Cordillera (1979/80-2013/14), covering the tropical latitudes in the north down to the sub-polar latitudes in the far south, including the Northern Patagonia Ice Field (NPI) and Southern Patagonia Ice Field (SPI). SnowModel - a fully integrated energy balance, blowing-snow distribution, multi-layer snowpack, and runoff routing model - was used to simulate glacier SMBs for the Andes Cordillera. The Randolph Glacier Inventory and NASA Modern-Era Retrospective Analysis for Research and Applications products, downscaled in SnowModel, allowed us to conduct relatively high-resolution simulations. The simulated glacier SMBs were verified against independent directly-observed and satellite gravimetry and altimetry-derived SMB, indicating a good statistical agreement. For glaciers in the Andes Cordillera, the 35-year mean annual SMB was found to be -1.13 m water equivalent. For both NPI and SPI, the mean SMB was positive (where calving is the likely reason for explaining why geodetic estimates are negative). Further, the spatio-temporal freshwater river runoff patterns from individual basins, including their runoff magnitude and change, were simulated. For the Andes Cordillera rivers draining to the Pacific Ocean, 86% of the simulated runoff originated from rain, 12% from snowmelt, and 2% from ice melt, whereas, for example, for Chile, the water-source distribution was 69, 24, and 7%, respectively. Along the Andes Cordillera, the 35-year mean basin outlet-specific runoff (L s-1 km-2) showed a characteristic regional hourglass shape pattern with highest runoff in both Colombia and Ecuador and in Patagonia, and lowest runoff in the Atacama Desert area.

  11. Development of Effective Procedures for Stormwater Thermal Pollution Potential Risk Mapping

    OpenAIRE

    Martin, Clinton James

    2017-01-01

    Thermal pollution of waterbodies occurring from heated stormwater runoff in urban catchments is a growing concern among municipalities in the United States. The U.S. Environmental Protection Agency (EPA) maintains regulatory criteria for temperature of waters of the U.S. as many species of aquatic life depend on an environment that maintains water temperatures below a certain threshold. Thermal pollution from urban stormwater runoff threatens the livelihoods of cold-water fish species, like t...

  12. Stormwater Treatment Evaluation of a Constructed Floating Wetland after Two Years Operation in an Urban Catchment

    OpenAIRE

    Christopher Walker; Katharina Tondera; Terry Lucke

    2017-01-01

    Constructed Floating Wetlands (CFW) for stormwater treatment are increasingly used to treat urban runoff. However, studies of large-scale systems and the long-term evaluation of their treatment efficiency are scarce. This article presents the final results of a two-year study of the pollutant removal performance of a CFW in a stormwater pond capturing runoff from a low-residential catchment in South-East Queensland (Australia) under subtropical conditions. Although the CFW treatment area to c...

  13. A mathematical model for soil solute transfer into surface runoff as influenced by rainfall detachment.

    Science.gov (United States)

    Yang, Ting; Wang, Quanjiu; Wu, Laosheng; Zhao, Guangxu; Liu, Yanli; Zhang, Pengyu

    2016-07-01

    Nutrients transport is a main source of water pollution. Several models describing transport of soil nutrients such as potassium, phosphate and nitrate in runoff water have been developed. The objectives of this research were to describe the nutrients transport processes by considering the effect of rainfall detachment, and to evaluate the factors that have greatest influence on nutrients transport into runoff. In this study, an existing mass-conservation equation and rainfall detachment process were combined and augmented to predict runoff of nutrients in surface water in a Loess Plateau soil in Northwestern Yangling, China. The mixing depth is a function of time as a result of rainfall impact, not a constant as described in previous models. The new model was tested using two different sub-models of complete-mixing and incomplete-mixing. The complete-mixing model is more popular to use for its simplicity. It captured the runoff trends of those high adsorption nutrients, and of nutrients transport along steep slopes. While the incomplete-mixing model predicted well for the highest observed concentrations of the test nutrients. Parameters inversely estimated by the models were applied to simulate nutrients transport, results suggested that both models can be adopted to describe nutrients transport in runoff under the impact of rainfall.

  14. Rainfall-runoff model HEC-HMS in a small inhomogeneous basin

    Science.gov (United States)

    Ponížilová, Iva; Unucka, Jan; Říhová, Veronika

    2014-05-01

    The contribution focuses on the applicability of the hydrologic rainfall-runoff model HEC-HMS to verify the effect of inhomogeneities of the basin surface. The simulation of an extreme rainfall-runoff episode using the HEC-HMS model should prove the influence of basin inhomogeneity on the speed and volume of runoff and the potential of watersheds on runoff mitigation. The area of interest is situated in North Bohemia, Czech Republic. Inhomogeneity of the Robecsky stream basin is caused by different physical-geographic conditions in the basin of the main reaches of the Robecsky stream and its major left tributary which is the Bobri stream. Before their confluence, both streams have a comparable catchment area of about 130 km2. Significant differences are manifested in average altitude of the basin, basin shape, basin slope, time of concentration and the proportion of forest areas. The Bobri stream shows more extreme runoff characteristics in combination with a smaller area of forestation. Another important factor affecting runoff from the basin is the proportion of watersheds that accumulate water in the landscape and cause runoff mitigation and slowdown. To illustrate the influence of watersheds Machovo Lake on the Robecsky stream and Holansky pond on the Bobri stream were selected. Machovo Lake is the third largest watershed in the territory of the Czech Republic. Holansky pond is the largest of the system of Holansky ponds. The Robecsky stream has the lowest runoff coefficient from the entire Ploucnice basin. The lakes surface-drainage area ratio is approximately 1.7% of the total catchment area of the Robecsky stream. The rainfall-runoff model HEC-HMS was utilized for the analysis and to determine the volume of runoff the method of CN curves was used that depends on hydrological properties of soils. For schematisation of extreme runoff conditions of the basin the precipitation period from 6th to 8th August 2010 was selected. Extremeness of peak flows of the

  15. Application of snowmelt runoff model (SRM in mountainous watersheds: A review

    Directory of Open Access Journals (Sweden)

    Shalamu ABUDU

    2012-06-01

    Full Text Available The snowmelt runoff model (SRM has been widely used in simulation and forecast of streamflow in snow-dominated mountainous basins around the world. This paper presents an overall review of worldwide applications of SRM in mountainous watersheds, particularly in data-sparse watersheds of northwestern China. Issues related to proper selection of input climate variables and parameters, and determination of the snow cover area (SCA using remote sensing data in snowmelt runoff modeling are discussed through extensive review of literature. Preliminary applications of SRM in northwestern China have shown that the model accuracies are relatively acceptable although most of the watersheds lack measured hydro-meteorological data. Future research could explore the feasibility of modeling snowmelt runoff in data-sparse mountainous watersheds in northwestern China by utilizing snow and glacier cover remote sensing data, geographic information system (GIS tools, field measurements, and innovative ways of model parameterization.

  16. Long-term runoff forecasting by combining hydrological models and meteorological records

    Science.gov (United States)

    Yang, Tao-Chang; Yu, Pao-Shan; Chen, Chiang-Chi

    2005-06-01

    Reservoir operation is generally based on the inflows of the upstream catchment of the reservoir. If the arriving inflows can be forecasted, that can benefit reservoir operation and management. This study attempts to construct a long-term inflow-forecasting model by combining a continuous rainfall-runoff model with the long-term weather outlook from the Central Weather Bureau of Taiwan. The analytical results demonstrate that the continuous rainfall-runoff model has good inflow simulation performance by using 10-day meteorological and inflow records over a 33-year period for model calibration and verification. The long-term inflow forecasting during the dry season was further conducted by combining the continuous rainfall-runoff model and the long-term weather outlook, which was found to have good performance.

  17. Snowmelt runoff modeling in simulation and forecasting modes with the Martinec-Mango model

    Science.gov (United States)

    Shafer, B.; Jones, E. B.; Frick, D. M. (Principal Investigator)

    1982-01-01

    The Martinec-Rango snowmelt runoff model was applied to two watersheds in the Rio Grande basin, Colorado-the South Fork Rio Grande, a drainage encompassing 216 sq mi without reservoirs or diversions and the Rio Grande above Del Norte, a drainage encompassing 1,320 sq mi without major reservoirs. The model was successfully applied to both watersheds when run in a simulation mode for the period 1973-79. This period included both high and low runoff seasons. Central to the adaptation of the model to run in a forecast mode was the need to develop a technique to forecast the shape of the snow cover depletion curves between satellite data points. Four separate approaches were investigated-simple linear estimation, multiple regression, parabolic exponential, and type curve. Only the parabolic exponential and type curve methods were run on the South Fork and Rio Grande watersheds for the 1980 runoff season using satellite snow cover updates when available. Although reasonable forecasts were obtained in certain situations, neither method seemed ready for truly operational forecasts, possibly due to a large amount of estimated climatic data for one or two primary base stations during the 1980 season.

  18. PERSiST: a flexible rainfall-runoff modelling toolkit for use with the INCA family of models

    Science.gov (United States)

    Futter, M. N.; Erlandsson, M. A.; Butterfield, D.; Whitehead, P. G.; Oni, S. K.; Wade, A. J.

    2014-02-01

    Runoff generation processes and pathways vary widely between catchments. Credible simulations of solute and pollutant transport in surface waters are dependent on models which facilitate appropriate, catchment-specific representations of perceptual models of the runoff generation process. Here, we present a flexible, semi-distributed landscape-scale rainfall-runoff modelling toolkit suitable for simulating a broad range of user-specified perceptual models of runoff generation and stream flow occurring in different climatic regions and landscape types. PERSiST (the Precipitation, Evapotranspiration and Runoff Simulator for Solute Transport) is designed for simulating present-day hydrology; projecting possible future effects of climate or land use change on runoff and catchment water storage; and generating hydrologic inputs for the Integrated Catchments (INCA) family of models. PERSiST has limited data requirements and is calibrated using observed time series of precipitation, air temperature and runoff at one or more points in a river network. Here, we apply PERSiST to the river Thames in the UK and describe a Monte Carlo tool for model calibration, sensitivity and uncertainty analysis.

  19. Runoff prediction in a poorly gauged basin using isotope-calibrated models

    Science.gov (United States)

    Yamanaka, Tsutomu; Ma, Wenchao

    2017-01-01

    Predictions in ungauged basins have been a major challenge in hydrologic sciences, and there is still much work needed to achieve robust and reliable predictions for such basins. Here, we propose and test a novel approach for predicting runoff from poorly gauged basins using a minimum complex model calibrated with isotope data alone (i.e., without observed discharge data). The model is composed of two water-stores (soil water and groundwater) and considers their connectivity to runoff in terms of both water and isotope budgets. In a meso-scale basin in which riverbed deformations frequently occur, making automatic observation of river discharge difficult, we measured hydrogen and oxygen isotope composition (δ2H and δ18O) of precipitation and river water twice-weekly for one year. Runoff predicted by the model agreed well with that observed monthly or bimonthly. Monte Carlo simulation revealed a strong coherence between model performance in isotope simulation and runoff prediction, demonstrating that the use of isotopes as dynamic proxies of calibration targets helps reliably constrain model parameters. Our results indicate that this approach can serve as a powerful tool for prediction of runoff hydrographs, particularly for basins in which the stage-discharge relationship is highly variable.

  20. Source-Based Modeling Of Urban Stormwater Quality Response to the Selected Scenarios Combining Future Changes in Climate and Socio-Economic Factors

    Science.gov (United States)

    Borris, Matthias; Leonhardt, Günther; Marsalek, Jiri; Österlund, Heléne; Viklander, Maria

    2016-08-01

    The assessment of future trends in urban stormwater quality should be most helpful for ensuring the effectiveness of the existing stormwater quality infrastructure in the future and mitigating the associated impacts on receiving waters. Combined effects of expected changes in climate and socio-economic factors on stormwater quality were examined in two urban test catchments by applying a source-based computer model (WinSLAMM) for TSS and three heavy metals (copper, lead, and zinc) for various future scenarios. Generally, both catchments showed similar responses to the future scenarios and pollutant loads were generally more sensitive to changes in socio-economic factors (i.e., increasing traffic intensities, growth and intensification of the individual land-uses) than in the climate. Specifically, for the selected Intermediate socio-economic scenario and two climate change scenarios (RSP = 2.6 and 8.5), the TSS loads from both catchments increased by about 10 % on average, but when applying the Intermediate climate change scenario (RCP = 4.5) for two SSPs, the Sustainability and Security scenarios (SSP1 and SSP3), the TSS loads increased on average by 70 %. Furthermore, it was observed that well-designed and maintained stormwater treatment facilities targeting local pollution hotspots exhibited the potential to significantly improve stormwater quality, however, at potentially high costs. In fact, it was possible to reduce pollutant loads from both catchments under the future Sustainability scenario (on average, e.g., TSS were reduced by 20 %), compared to the current conditions. The methodology developed in this study was found useful for planning climate change adaptation strategies in the context of local conditions.

  1. The ensemble particle filter (EnPF) in rainfall-runoff models

    NARCIS (Netherlands)

    Van Delft, G.; El Serafy, G.Y.; Heemink, A.W.

    2009-01-01

    Rainfall-runoff models play a very important role in flood forecasting. However, these models contain large uncertainties caused by errors in both the model itself and the input data. Data assimilation techniques are being used to reduce these uncertainties. The ensemble Kalman filter (EnKF) and the

  2. The ensemble particle filter (EnPF) in rainfall-runoff models

    NARCIS (Netherlands)

    Van Delft, G.; El Serafy, G.Y.; Heemink, A.W.

    2009-01-01

    Rainfall-runoff models play a very important role in flood forecasting. However, these models contain large uncertainties caused by errors in both the model itself and the input data. Data assimilation techniques are being used to reduce these uncertainties. The ensemble Kalman filter (EnKF) and the

  3. Runoff of pesticides from rice fields in the Ile de Camargue (Rhone river delta, France): Field study and modeling

    Energy Technology Data Exchange (ETDEWEB)

    Comoretto, Laetitia; Arfib, Bruno; Talva, Romain; Chauvelon, Philippe; Pichaud, Marc; Chiron, Serge [Laboratoire Chimie et Environnement, Universite de Provence, Case 29, 3, Place Victor Hugo, F-13331 Marseille Cedex 3 (France); Hoehener, Patrick [Laboratoire Chimie et Environnement, Universite de Provence, Case 29, 3, Place Victor Hugo, F-13331 Marseille Cedex 3 (France)], E-mail: hoehener@up.univ-mrs.fr

    2008-02-15

    A field study on the runoff of pesticides was conducted during the cultivation period in 2004 on a hydraulically isolated rice farm of 120 ha surface with one central water outlet. Four pesticides were studied: Alphamethrin, MCPA, Oxadiazon, and Pretilachlor. Alphamethrin concentrations in runoff never exceeded 0.001 {mu}g L{sup -1}. The three other pesticides were found in concentrations between 5.2 and 28.2 {mu}g L{sup -1} in the runoff water shortly after the application and decreased thereafter. The data for MCPA compared reasonably well with predictions by an analytical runoff model, accounting for volatilization, degradation, leaching to groundwater, and sorption to soil. The runoff model estimated that runoff accounted for as much as 18-42% of mass loss for MCPA. Less runoff is observed and predicted for Oxadiazon and Pretilachlor. It was concluded that runoff from rice paddies carries important loads of dissolved pesticides to the wetlands in the Ile de Camargue, and that the model can be used to predict this runoff. - Runoff of dissolved pesticides was measured on a rice farm in the Camargue (France) and modeled with an analytical model.

  4. Response of Arctic Ocean stratification to changing river runoff in a column model

    Science.gov (United States)

    Nummelin, Aleksi; Li, Camille; Smedsrud, Lars H.

    2015-04-01

    A one-dimensional model of the atmosphere-ice-ocean column is used to study the effects of changing river runoff to the Arctic Ocean. River runoff is the largest contributor of freshwater to the Arctic and is expected to increase as the hydrological cycle accelerates due to global warming. The column model simulates the stratification of the Arctic Ocean reasonably well, capturing important features such as the fresh surface layer, the salty cold halocline, and the temperature maximum within the Atlantic Water layer. The model is run for 500 years with prescribed boundary conditions to reach steady state solutions. Increasing river runoff is found to strengthen the stratification and to produce a fresher and shallower surface mixed layer with warming (up to ˜1°C for a doubling of present-day runoff) in the Atlantic Water layer below. An important consequence is that the effect of the larger vertical temperature gradient is able to balance that of the stronger stratification and yield a close to constant vertical heat flux toward the surface. As a result, the sea ice response is small, showing only slight increase (up to ˜15 cm for a doubling of present-day runoff) in annual mean ice thickness. Limitations of the study include the idealized nature of the column model and uncertainties in the background vertical mixing within the Arctic Ocean.

  5. Sensitivity analysis of runoff modeling to statistical downscaling models in the western Mediterranean

    Science.gov (United States)

    Grouillet, Benjamin; Ruelland, Denis; Vaittinada Ayar, Pradeebane; Vrac, Mathieu

    2016-03-01

    This paper analyzes the sensitivity of a hydrological model to different methods to statistically downscale climate precipitation and temperature over four western Mediterranean basins illustrative of different hydro-meteorological situations. The comparison was conducted over a common 20-year period (1986-2005) to capture different climatic conditions in the basins. The daily GR4j conceptual model was used to simulate streamflow that was eventually evaluated at a 10-day time step. Cross-validation showed that this model is able to correctly reproduce runoff in both dry and wet years when high-resolution observed climate forcings are used as inputs. These simulations can thus be used as a benchmark to test the ability of different statistically downscaled data sets to reproduce various aspects of the hydrograph. Three different statistical downscaling models were tested: an analog method (ANALOG), a stochastic weather generator (SWG) and the cumulative distribution function-transform approach (CDFt). We used the models to downscale precipitation and temperature data from NCEP/NCAR reanalyses as well as outputs from two general circulation models (GCMs) (CNRM-CM5 and IPSL-CM5A-MR) over the reference period. We then analyzed the sensitivity of the hydrological model to the various downscaled data via five hydrological indicators representing the main features of the hydrograph. Our results confirm that using high-resolution downscaled climate values leads to a major improvement in runoff simulations in comparison to the use of low-resolution raw inputs from reanalyses or climate models. The results also demonstrate that the ANALOG and CDFt methods generally perform much better than SWG in reproducing mean seasonal streamflow, interannual runoff volumes as well as low/high flow distribution. More generally, our approach provides a guideline to help choose the appropriate statistical downscaling models to be used in climate change impact studies to minimize the range

  6. Permeable pavement and stormwater management systems: a review.

    Science.gov (United States)

    Imran, H M; Akib, Shatirah; Karim, Mohamed Rehan

    2013-01-01

    Uncontrolled stormwater runoff not only creates drainage problems and flash floods but also presents a considerable threat to water quality and the environment. These problems can, to a large extent, be reduced by a type of stormwater management approach employing permeable pavement systems (PPS) in urban, industrial and commercial areas, where frequent problems are caused by intense undrained stormwater. PPS could be an efficient solution for sustainable drainage systems, and control water security as well as renewable energy in certain cases. Considerable research has been conducted on the function of PPS and their improvement to ensure sustainable drainage systems and water quality. This paper presents a review of the use of permeable pavement for different purposes. The paper focuses on drainage systems and stormwater runoff quality from roads, driveways, rooftops and parking lots. PPS are very effective for stormwater management and water reuse. Moreover, geotextiles provide additional facilities to reduce the pollutants from infiltrate runoff into the ground, creating a suitable environment for the biodegradation process. Furthermore, recently, ground source heat pumps and PPS have been found to be an excellent combination for sustainable renewable energy. In addition, this study has identified several gaps in the present state of knowledge on PPS and indicates some research needs for future consideration.

  7. Trees and Streets as Drivers of Urban Stormwater Nutrient Pollution.

    Science.gov (United States)

    Janke, Benjamin D; Finlay, Jacques C; Hobbie, Sarah E

    2017-09-05

    Expansion of tree cover is a major management goal in cities because of the substantial benefits provided to people, and potentially to water quality through reduction of stormwater volume by interception. However, few studies have addressed the full range of potential impacts of trees on urban runoff, which includes deposition of nutrient-rich leaf litter onto streets connected to storm drains. We analyzed the influence of trees on stormwater nitrogen and phosphorus export across 19 urban watersheds in Minneapolis-St. Paul, MN, U.S.A., and at the scale of individual streets within one residential watershed. Stormwater nutrient concentrations were highly variable across watersheds and strongly related to tree canopy over streets, especially for phosphorus. Stormwater nutrient loads were primarily related to road density, the dominant control over runoff volume. Street canopy exerted opposing effects on loading, where elevated nutrient concentrations from trees near roads outweighed the weak influence of trees on runoff reduction. These results demonstrate that vegetation near streets contributes substantially to stormwater nutrient pollution, and therefore to eutrophication of urban surface waters. Urban landscape design and management that account for trees as nutrient pollution sources could improve water quality outcomes, while allowing cities to enjoy the myriad benefits of urban forests.

  8. Real time adjustment of slow changing flow components in distributed urban runoff models

    DEFF Research Database (Denmark)

    Borup, Morten; Grum, M.; Mikkelsen, Peter Steen

    2011-01-01

    . This information is then used to update the states of the hydrological model. The method is demonstrated on the 20 km2 Danish urban catchment of Ballerup, which has substantial amount of infiltration inflow after succeeding rain events, for a very rainy period of 17 days in August 2010. The results show big......In many urban runoff systems infiltrating water contributes with a substantial part of the total inflow and therefore most urban runoff modelling packages include hydrological models for simulating the infiltrating inflow. This paper presents a method for deterministic updating of the hydrological...

  9. Estimation of parameters in a distributed precipitation-runoff model for Norway

    Directory of Open Access Journals (Sweden)

    S. Beldring

    2003-01-01

    Full Text Available A distributed version of the HBV-model using 1 km2 grid cells and daily time step was used to simulate runoff from the entire land surface of Norway for the period 1961-1990. The model was sensitive to changes in small scale properties of the land surface and the climatic input data, through explicit representation of differences between model elements, and by implicit consideration of sub-grid variations in moisture status. A geographically transferable set of model parameters was determined by a multi-criteria calibration strategy, which simultaneously minimised the residuals between model simulated and observed runoff from 141 Norwegian catchments located in areas with different runoff regimes and landscape characteristics. Model discretisation units with identical landscape classification were assigned similar parameter values. Model performance was evaluated by simulating discharge from 43 independent catchments. Finally, a river routing procedure using a kinematic wave approximation to open channel flow was introduced in the model, and discharges from three additional catchments were calculated and compared with observations. The model was used to produce a map of average annual runoff for Norway for the period 1961-1990. Keywords: distributed model, multi-criteria calibration, global parameters, ungauged catchments.

  10. Modeling of hydrographs in torrent catchments by use of improved field data and adapted precipitation/runoff models

    Science.gov (United States)

    Kohl, B.; Klebinder, K.; Kirnbauer, R.; Markart, G.

    2009-04-01

    For description of runoff formation in alpine catchments still often simple runoff formulas are used on the one hand. On the other hand many precipitation / runoff models for assessment of runoff characteristics in mesoscale and microscale catchments require detailed input data and some are using algorithms which don't describe runoff processes "process-oriented". This especially applies to lumped and to some conceptual models. Fully distributed models mostly require enormous effort for determining serious catchment description parameters. As a first step into the direction of a time and cost sparing but still process based assessment of runoff development in alpine torrent catchments a two column-procedure has been developed at the BFW in cooperation with university scientists and in cooperation with the Austrian Avalanche and Torrent Control Service and the Bavarian Environmental Agency: 1) Based on the results of about 700 simulations of torrential rain on various soil vegetation complexes and land-use forms in the Eastern Alps a code of practice for assessment of surface runoff coefficients in torrential rain has been developed. By use of three indicator groups (soil conditions, sort and condition of plant cover, way and intensity of land-use / cultivation) runoff coefficients and surface roughness coefficients can be easily attributed to runoff contributing hydrological vegetation units. The big advantage: Dominant infiltration and runoff controlling processes are integrated in the assessed runoff and surface roughness coefficients. The manual is freely available under: http://bfw.ac.at/rz/bfwcms.web?dok=4342 (in German language). 2) The coefficients derived from field studies and/or GIS analysis form input parameters for the precipitation / runoff model ZEMOKOST (The runtime Method of ZEller MOdified by KOhl and STepanek), an MS-EXCEL based calculation tool which can be used with or without GIS-environment. The approach is permanently improved by addition of

  11. Green-roof as a solution to solve stormwater management issues? Assessment on a long time period at the parcel scale

    Science.gov (United States)

    Versini, P.-A.; Petrucci, G.; de Gouvello, B.

    2014-09-01

    Experimental green-roof rainfall-runoff observations have shown a positive impact on stormwater management at the building scale; with a decrease in the peak discharge and a decrease in runoff volume. This efficiency of green-roofs varies from one rainfall event to another depending on precipitation characteristics and substrate antecedent conditions. Due to this variability, currently, green-roofs are rarely officially used as a regulation tool to manage stormwater. Indeed, regulation rules governing the connection to the stormwater network are usually based on absolute threshold values that always have to be respected: maximum areal flow-rate or minimum retention volume for example. In this context, the aim of this study is to illustrate how a green-roof could represent an alternative to solve stormwater management issues, if the regulation rules were further based on statistics. For this purpose, a modelling scheme has been established at the parcel scale to simulate the hydrological response of several roof configurations: impervious, strictly regulated (in terms of areal flow-rate or retention volume), and covered by different types of green-roof matter. Simulations were carried out on a long precipitation time period (23 years) that included a large and heterogeneous set of hydrometeorological conditions. Results obtained for the different roof configurations were compared. Based on the return period of the rainfall event, the probability to respect some regulation rules (defined from real situations) was assessed. They illustrate that green-roofs reduce stormwater runoff compared to an impervious roof surface and can guarantee the respect of the regulation rules in most of the cases. Moreover, their implementation can appear more realistic than that of other infrastructures strictly complying with regulations and demanding significant storage capacity.

  12. Estimation of parameters in a distributed precipitation-runoff model for Norway

    Science.gov (United States)

    Beldring, Stein; Engeland, Kolbjørn; Roald, Lars A.; Roar Sælthun, Nils; Voksø, Astrid

    A distributed version of the HBV-model using 1 km2 grid cells and daily time step was used to simulate runoff from the entire land surface of Norway for the period 1961-1990. The model was sensitive to changes in small scale properties of the land surface and the climatic input data, through explicit representation of differences between model elements, and by implicit consideration of sub-grid variations in moisture status. A geographically transferable set of model parameters was determined by a multi-criteria calibration strategy, which simultaneously minimised the residuals between model simulated and observed runoff from 141 Norwegian catchments located in areas with different runoff regimes and landscape characteristics. Model discretisation units with identical landscape classification were assigned similar parameter values. Model performance was evaluated by simulating discharge from 43 independent catchments. Finally, a river routing procedure using a kinematic wave approximation to open channel flow was introduced in the model, and discharges from three additional catchments were calculated and compared with observations. The model was used to produce a map of average annual runoff for Norway for the period 1961-1990.

  13. A two-stage storage routing model for green roof runoff detention.

    Science.gov (United States)

    Vesuviano, Gianni; Sonnenwald, Fred; Stovin, Virginia

    2014-01-01

    Green roofs have been adopted in urban drainage systems to control the total quantity and volumetric flow rate of runoff. Modern green roof designs are multi-layered, their main components being vegetation, substrate and, in almost all cases, a separate drainage layer. Most current hydrological models of green roofs combine the modelling of the separate layers into a single process; these models have limited predictive capability for roofs not sharing the same design. An adaptable, generic, two-stage model for a system consisting of a granular substrate over a hard plastic 'egg box'-style drainage layer and fibrous protection mat is presented. The substrate and drainage layer/protection mat are modelled separately by previously verified sub-models. Controlled storm events are applied to a green roof system in a rainfall simulator. The time-series modelled runoff is compared to the monitored runoff for each storm event. The modelled runoff profiles are accurate (mean Rt(2) = 0.971), but further characterization of the substrate component is required for the model to be generically applicable to other roof configurations with different substrate.

  14. Toxicity of stormwater treatment pond sediments to Hyallela azteca (Amphipoda)

    Science.gov (United States)

    Karouna-Renier, N.K.; Sparling, D.W.

    1997-01-01

    Stormwater wetlands are created to contain runoff from human developments and are designed to retain contaminants such as heavy metals, petroleum hydrocarbons, silt, pesticides, and nutrients before the runoff enter natural waterways. Because of this design, stormwater wetlands have a potential of becoming toxic sinks to organisms utilizing the wetlands for habitat. We conducted a 10-day sediment bioassay on Hyallela azteca as part of a larger study on the possible hazards of stormwater wetlands to aquatic invertebrates. Water and sediments from 10 wetlands separated into reference, residential, commercial, and highway land uses were used. No differences in survival were observed among land use categories, possibly because the ratio of acid volatile sulfides/simultaneously extractable metals (AVS/SEM) was > 1.0 for all of the ponds tested; values > 1 in this ratio are indications that toxic metals may not be bioavailable. Survival and growth rates correlated positively with AVS.

  15. Conditioning rainfall-runoff model parameters to reduce prediction uncertainty in ungauged basins

    Science.gov (United States)

    Visessri, S.; McIntyre, N.; Maksimovic, C.

    2012-12-01

    Conditioning rainfall-runoff model parameters in ungauged catchments in Thailand presents problems common to ungauged basins involving data availability, data quality, and rainfall-runoff model suitability, which all contribute to prediction uncertainty. This paper attempts to improve the estimation of streamflow in ungauged basins and reduce associated uncertainties using the approaches of conditioning the prior parameter space. 35 catchments from the upper Ping River basin, Thailand are selected as a case study. The catchments have a range of attributes e.g. catchment sizes 20-6350 km2, elevations 632-1529 m above sea level. and annual rainfall 846-1447 mm/year. For each catchment, three indices - rainfall-runoff elasticity, base flow index and runoff coefficient - are calculated using the observed rainfall-runoff data and regression equations relating these indices to the catchment attributes are identified. Uncertainty in expected indices is defined by the regression error distribution, approximated by a Gaussian model. The IHACRES model is applied for simulating streamflow. The IHACRES parameters are randomly sampled from their presumed prior parameter space. For each sampled parameter set, the streamflow and hence the three indices are modelled. The parameter sets are conditioned on the probability distributions of the regionalised indices, allowing ensemble predictions to be made. The objective function, NSE, calculated for daily and weekly time steps from the water years 1995-2000, is used to assess model performance. Ability to capture observed streamflow and the precision of the estimate is evaluated using reliability and sharpness measures. Similarity in modelled and expected indices contributes to good objective function values. Using only the regionalised runoff coefficient to condition the model yields better NSE values compared to using either only the rainfall-runoff elasticity or only the base flow index. Conditioning on the runoff coefficient

  16. A System Dynamics Approach to Modelling the Degradation of Biochemical Oxygen Demand in A Constructed Wetland Receiving Stormwater Runoff

    Science.gov (United States)

    1995-12-01

    conventional treatment plants " are: "Constructed wetland systems (1) are relatively inexpensive to construct and operate; (2) are easy to maintain; (3) provide... macrophytes are divided into free floating and rooted forms. The rooted forms are further subdivided into emergent , floating and submerged classes...to state that "the removal of larger particles protects one of the key roles of emergent aquatic macrophytes in the wetlands which is the provision

  17. Uncertainty based modeling of rainfall-runoff: Combined differential evolution adaptive Metropolis (DREAM) and K-means clustering

    Science.gov (United States)

    Zahmatkesh, Zahra; Karamouz, Mohammad; Nazif, Sara

    2015-09-01

    Simulation of rainfall-runoff process in urban areas is of great importance considering the consequences and damages of extreme runoff events and floods. The first issue in flood hazard analysis is rainfall simulation. Large scale climate signals have been proved to be effective in rainfall simulation and prediction. In this study, an integrated scheme is developed for rainfall-runoff modeling considering different sources of uncertainty. This scheme includes three main steps of rainfall forecasting, rainfall-runoff simulation and future runoff prediction. In the first step, data driven models are developed and used to forecast rainfall using large scale climate signals as rainfall predictors. Due to high effect of different sources of uncertainty on the output of hydrologic models, in the second step uncertainty associated with input data, model parameters and model structure is incorporated in rainfall-runoff modeling and simulation. Three rainfall-runoff simulation models are developed for consideration of model conceptual (structural) uncertainty in real time runoff forecasting. To analyze the uncertainty of the model structure, streamflows generated by alternative rainfall-runoff models are combined, through developing a weighting method based on K-means clustering. Model parameters and input uncertainty are investigated using an adaptive Markov Chain Monte Carlo method. Finally, calibrated rainfall-runoff models are driven using the forecasted rainfall to predict future runoff for the watershed. The proposed scheme is employed in the case study of the Bronx River watershed, New York City. Results of uncertainty analysis of rainfall-runoff modeling reveal that simultaneous estimation of model parameters and input uncertainty significantly changes the probability distribution of the model parameters. It is also observed that by combining the outputs of the hydrological models using the proposed clustering scheme, the accuracy of runoff simulation in the

  18. Application of pesticide transport model for simulating diazinon runoff in California’s central valley

    Science.gov (United States)

    Joyce, Brian A.; Wallender, Wesley W.; Mailapalli, Damodhara R.

    2010-12-01

    Dormant spray application of pesticides to almond and other stone fruit orchards is the main source of diazinon during the winter in California's central valley. Understanding the pesticide transport and the tradeoffs associated with the various management practices is greatly facilitated by the use of physically-based contaminant transport models. In this study, performance of Joyce's et al. (2008) pesticide transport model was evaluated using experimental data collected from two ground treatments such as resident vegetation and bare soil. The model simulation results obtained in calibration and validation process were analyzed for pesticide concentration and total load. The pesticide transport model accurately predicted the pesticide concentrations and total load in the runoff from bare field and was capable of simulating chemical responses to rainfall-runoff events. In case of resident vegetation, the model results exhibited a larger range of variation than was observed in the bare soil simulations due to increased model parameterization with the addition of foliage and thatch compartments. Furthermore, the model was applied to study the effect of runoff lag time, extent of crop cover, organic content of soil and post-application irrigation on the pesticide peak concentration and total load. Based on the model results, recommendations were suggested to growers prior to implementing certain management decisions to mitigate diazinon transport in the orchard's spray runoff.

  19. Multi-criteria validation of artificial neural network rainfall-runoff modeling

    Directory of Open Access Journals (Sweden)

    R. Modarres

    2008-12-01

    Full Text Available In this study we propose a comprehensive multi-criteria validation test for rainfall-runoff modeling by artificial neural networks. This study applies 17 global statistics and 3 additional non-parametric tests to evaluate the ANNs. The weakness of global statistics for validation of ANN is demonstrated by rainfall-runoff modeling of the Plasjan Basin in the western region of the Zayandehrud watershed, Iran. Although the global statistics showed that the multi layer perceptron with 4 hidden layers (MLP4 is the best ANN for the basin comparing with other MLP networks and empirical regression model, but the non-parametric tests illustrate that neither the ANNs nor the regression model are able to reproduce the probability distribution of observed runoff in validation phase. However, the MLP4 network is the best network to reproduce the mean and variance of the observed runoff based on non-parametric tests. The performance of ANNs and empirical model was also demonstrated for low-medium and high flows. Although the MLP4 network gives the best performance among ANNs for low-medium and high flows based on different statistics but the empirical model shows better results. However, none of the models is able to simulate the frequency distribution of low-medium and high flows according to non-parametric tests. This study illustrates that the modelers should select appropriate and relevant evaluation measures from the set of existing metrics based on the particular requirements of each individual applications.

  20. Rainfall-runoff model for prediction of waterborne viral contamination in a small river catchment

    Science.gov (United States)

    Gelati, E.; Dommar, C.; Lowe, R.; Polcher, J.; Rodó, X.

    2013-12-01

    We present a lumped rainfall-runoff model aimed at providing useful information for the prediction of waterborne viral contamination in small rivers. Viral contamination of water bodies may occur because of the discharge of sewage effluents and of surface runoff over areas affected by animal waste loads. Surface runoff is caused by precipitation that cannot infiltrate due to its intensity and to antecedent soil water content. It may transport animal feces to adjacent water bodies and cause viral contamination. We model streamflow by separating it into two components: subsurface flow, which is produced by infiltrated precipitation; and surface runoff. The model estimates infiltrated and non-infiltrated precipitation and uses impulse-response functions to compute the corresponding fractions of streamflow. The developed methodologies are applied to the Glafkos river, whose catchment extends for 102 km2 and includes the city of Patra. Streamflow and precipitation observations are available at a daily time resolution. Waterborne virus concentration measurements were performed approximately every second week from the beginning of 2011 to mid 2012. Samples were taken at several locations: in river water upstream of Patras and in the urban area; in sea water at the river outlet and approximately 2 km south-west of Patras; in sewage effluents before and after treatment. The rainfall-runoff model was calibrated and validated using observed streamflow and precipitation data. The model contribution to waterborne viral contamination prediction was benchmarked by analyzing the virus concentration measurements together with the estimated surface runoff values. The presented methodology may be a first step towards the development of waterborne viral contamination alert systems. Predicting viral contamination of water bodies would benefit sectors such as water supply and tourism.

  1. Assessment of Noah land surface model with various runoff parameterizations over a Tibetan river

    Science.gov (United States)

    Zheng, Donghai; Van Der Velde, Rogier; Su, Zhongbo; Wen, Jun; Wang, Xin

    2017-02-01

    Runoff parameterizations currently adopted by the (i) Noah-MP model, (ii) Community Land Model (CLM), and (iii) CLM with variable infiltration capacity hydrology (CLM-VIC) are incorporated into the structure of Noah land surface model, and the impact of these parameterizations on the runoff simulations is investigated for a Tibetan river. Four numerical experiments are conducted with the default Noah and three aforementioned runoff parameterizations. Each experiment is forced with the same set of atmospheric forcing, vegetation, and soil parameters. In addition, the Community Earth System Model database provides the maximum surface saturated area parameter for the Noah-MP and CLM parameterizations. A single-year recurrent spin-up is adopted for the initialization of each model run to achieve equilibrium states. Comparison with discharge measurements shows that each runoff parameterization produces significant differences in the separation of total runoff into surface and subsurface components and that the soil water storage-based parameterizations (Noah and CLM-VIC) outperform the groundwater table-based parameterizations (Noah-MP and CLM) for the seasonally frozen and high-altitude Tibetan river. A parameter sensitivity experiment illustrates that this underperformance of the groundwater table-based parameterizations cannot be resolved through calibration. Further analyses demonstrate that the simulations of other surface water and energy budget components are insensitive to the selected runoff parameterizations, due to the strong control of the atmosphere on simulated land surface fluxes induced by the diurnal dependence of the roughness length for heat transfer and the large water retention capacity of the highly organic top soils over the plateau.

  2. Analysis and Modeling of Time-Correlated Characteristics of Rainfall-Runoff Similarity in the Upstream Red River Basin

    Directory of Open Access Journals (Sweden)

    Xiuli Sang

    2012-01-01

    Full Text Available We constructed a similarity model (based on Euclidean distance between rainfall and runoff to study time-correlated characteristics of rainfall-runoff similar patterns in the upstream Red River Basin and presented a detailed evaluation of the time correlation of rainfall-runoff similarity. The rainfall-runoff similarity was used to determine the optimum similarity. The results showed that a time-correlated model was found to be capable of predicting the rainfall-runoff similarity in the upstream Red River Basin in a satisfactory way. Both noised and denoised time series by thresholding the wavelet coefficients were applied to verify the accuracy of model. And the corresponding optimum similar sets obtained as the equation solution conditions showed an interesting and stable trend. On the whole, the annual mean similarity presented a gradually rising trend, for quantitatively estimating comprehensive influence of climate change and of human activities on rainfall-runoff similarity.

  3. Development of sustainable stormwater management using simulation-optimization approach under climate change

    Science.gov (United States)

    Huang, Yu-ru; Tung, Ching-pin

    2015-04-01

    Climate change had altered the hydrological processes globally with result that the extreme events have an increase in both the magnitude and the frequency. In particular, the high intensity rainfall cause the severe flooding had significantly impacted on human life and property in recently year. The traditional facility to handle runoff is the drainage system which is designed in accordance with the intensity-duration-frequency (IDF) curve. However, the flooding occurs once the drainage capacity is overwhelmed by excess stormwater. Thus the general solution are that expanding and upgrading the existing drainage system or increasing the design return period for new development areas to reduce flooding. Besides, another technique which is low impact development(LID) is regarded as more sustainable solution for stormwater management. The concept of LID is to control stormwater at the source by decentralized practices and mimic the predevelopment hydrologic conditions including storage, retention and high rate of infiltration. In contrast to conventional drainage system aims to move runoff away as quickly as possible, the LID approach attempts to keep runoff on site to reduce peak and volume of flow. The purpose of this research is to identify the most cost-effective measures for stormwater management after the analysis of the strategies combining drainage system and LID on various land use planning. The case study is a rural community in Hsinchu in Taiwan, and having residential areas, farms and pond. It is assumed that two land use layout are planned and drainage system are designed for 2-,and 5-year return period events. On the other hand, three LID technologies, namely green roof, porous pavement and rain barrel, are selected to place in the scenario of the drainage system for 2-year return period event, and the minimal peak flow is target to optimize LID placement by simulated annealing algorithm. Moreover, the design storm under climate change are derived from

  4. Cistern Performance for Stormwater Management in Camden, NJ

    Science.gov (United States)

    The Camden County Municipal Utilities Authority (CCMUA) installed cisterns at locations around the city of Camden, NJ. Cisterns provide a cost effective approach to reduce stormwater runoff volume and peak discharge. The collected water can be substituted for potable water in s...

  5. BMPs in urban stormwater management in Denmark and Sweden

    DEFF Research Database (Denmark)

    Mikkelsen, Peter Steen; Viklander, M.; Linde, Jens Jørgen;

    2002-01-01

    Best Management Practices (BMPs) for control of stormwater runoff include structural elemts (structural BMPs) that can be applied on the local scale (e.g. infiltration), the drainage catchment scale (e.g. ponds and treatment, or wetlands) and the receiving water scale (e.g. retrofitting of river ...

  6. Development of a Cell-based Model to Derive Direct Runoff Hydrographs for Ungauged Mountainous Basins

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A model to derive direct runoff hydrograph for an ungauged basin using the physical properties of the basin is presented. The basin is divided into grid cells and canal elements. Overland flow is generated from each grid cell of the basin by application of continuous effective rainfall of 1 mm/hr to the basin. The flow generated is routed through downstream grid cells and the canal elements using the kinematic wave approach. The travel time for direct runoff from each grid cell to the basin outlet is calculated and the S-curve is derived for the basin.The S-curve is used to derive the unit hydrograph of a given duration for the basin. The model, referred as Cell-basin model was applied to the Upper Kotmale Basin in Sri Lanka and the model predictions of direct runoff hydrographs for rainfall events agreed with the observations to a reasonable accuracy. Comparison of the unit hydrographs obtained from the model and from the conventional Snyder's synthetic unit hydrograph using regionalized parameters assuming the basin as an ungauged basin, with the unit hydrograph derived from the observations showed that the model predicted unit hydrograph was more suitable than that obtained by Snyder's method for Sri Lankan up country basins. Thus, the present model is a useful tool to obtain direct runoff hydrograph for ungauged basins.

  7. Evaluation of stormwater micropollutant source control and end-of-pipe control strategies using an uncertainty-calibrated integrated dynamic simulation model

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Sharma, Anitha Kumari; Ledin, Anna;

    2015-01-01

    by monitoring campaigns and to evaluate the performance of different strategies based on model simulation results. This study presents an example where six different control strategies, including both source-control and end-of-pipe treatment, were compared. The comparison focused on fluxes of heavy metals......The estimation of micropollutant (MP) fluxes in stormwater systems is a fundamental prerequisite when preparing strategies to reduce stormwater MP discharges to natural waters. Dynamic integrated models can be important tools in this step, as they can be used to integrate the limited data provided...... scenarios in terms of discharged MP fluxes, compliance with water quality criteria, and sediment accumulation. Source-control strategies obtained better results in terms of reduction of MP emissions, but all the simulated strategies failed in fulfilling the criteria based on emission limit values...

  8. Principles for urban stormwater management to protect stream ecosystems

    Science.gov (United States)

    Walsh, Christopher J.; Booth, Derek B.; Burns, Matthew J.; Fletcher, Tim D.; Hale, Rebecca L.; Hoang, Lan N.; Livingston, Grant; Rippy, Megan A.; Roy, Allison; Scoggins, Mateo; Wallace, Angela

    2016-01-01

    Urban stormwater runoff is a critical source of degradation to stream ecosystems globally. Despite broad appreciation by stream ecologists of negative effects of stormwater runoff, stormwater management objectives still typically center on flood and pollution mitigation without an explicit focus on altered hydrology. Resulting management approaches are unlikely to protect the ecological structure and function of streams adequately. We present critical elements of stormwater management necessary for protecting stream ecosystems through 5 principles intended to be broadly applicable to all urban landscapes that drain to a receiving stream: 1) the ecosystems to be protected and a target ecological state should be explicitly identified; 2) the postdevelopment balance of evapotranspiration, stream flow, and infiltration should mimic the predevelopment balance, which typically requires keeping significant runoff volume from reaching the stream; 3) stormwater control measures (SCMs) should deliver flow regimes that mimic the predevelopment regime in quality and quantity; 4) SCMs should have capacity to store rain events for all storms that would not have produced widespread surface runoff in a predevelopment state, thereby avoiding increased frequency of disturbance to biota; and 5) SCMs should be applied to all impervious surfaces in the catchment of the target stream. These principles present a range of technical and social challenges. Existing infrastructural, institutional, or governance contexts often prevent application of the principles to the degree necessary to achieve effective protection or restoration, but significant potential exists for multiple co-benefits from SCM technologies (e.g., water supply and climate-change adaptation) that may remove barriers to implementation. Our set of ideal principles for stream protection is intended as a guide for innovators who seek to develop new approaches to stormwater management rather than accept seemingly

  9. Modelling pH, alkalinity and runoff in a lakeless forested basin in southern Finland

    Energy Technology Data Exchange (ETDEWEB)

    Lepistoe, A.; Jaervi, T.; Seuna, P.

    1987-01-01

    The Swedish PULSE model, with the HBV model as the hydrological part, has been used for simulation of the pH and alkalinity of runoff. In Sweden the model has been applied with good results to forested basins that have lakes. In the present study the model was applied to a forested basin without lakes, in order to test its suitability in this case. The model was calibrated to a small (0.69 km{sup 2}) basin using a 12-year time period (1972-83;R{sup 2}=0.80 for runoff). Verification was carried out with data of the intensively monitored years 1984-85 (R{sup 2}=0.84 for runoff, R{sup 2}=0.71 for pH). The results show that the PULSE model can also be applied satisfactorily to basins without lakes. The simulation provides reference values fo use in destinguishing long term changes in the runoff water quality from natural short-term variations. 5 figures, 10 references. (author).

  10. A CN-Based Ensembled Hydrological Model for Enhanced Watershed Runoff Prediction

    Directory of Open Access Journals (Sweden)

    Muhammad Ajmal

    2016-01-01

    Full Text Available A major structural inconsistency of the traditional curve number (CN model is its dependence on an unstable fixed initial abstraction, which normally results in sudden jumps in runoff estimation. Likewise, the lack of pre-storm soil moisture accounting (PSMA procedure is another inherent limitation of the model. To circumvent those problems, we used a variable initial abstraction after ensembling the traditional CN model and a French four-parameter (GR4J model to better quantify direct runoff from ungauged watersheds. To mimic the natural rainfall-runoff transformation at the watershed scale, our new parameterization designates intrinsic parameters and uses a simple structure. It exhibited more accurate and consistent results than earlier methods in evaluating data from 39 forest-dominated watersheds, both for small and large watersheds. In addition, based on different performance evaluation indicators, the runoff reproduction results show that the proposed model produced more consistent results for dry, normal, and wet watershed conditions than the other models used in this study.

  11. A dynamic continental runoff routing model applied to the last Northern Hemisphere deglaciation

    Directory of Open Access Journals (Sweden)

    H. Goelzer

    2011-10-01

    Full Text Available We describe and evaluate a dynamical continental runoff routing model for the Northern Hemisphere that calculates the runoff pathways in response to topographic modifications due to changes in ice thickness and isostatic adjustment. The algorithm is based on the steepest gradient method and takes as simplifying assumption that depressions are filled at all times and water drains through the lowest outlet points. It also considers changes in water storage and lake drainage that become important in the presence of large ice dammed proglacial lakes. Although applicable to other scenarios as well, the model was conceived to study the routing of freshwater fluxes during the last Northern Hemisphere deglaciation. For that specific application we simulated the Northern Hemisphere ice sheets with an existing 3-D thermomechanical ice sheet model, which calculates changes in topography due to changes in ice cover and isostatic adjustment, as well as the evolution of freshwater fluxes resulting from surface ablation, iceberg calving and basal melt. The continental runoff model takes this input, calculates the drainage pathways and routes the freshwater fluxes to the surface grid points of an existing ocean model. This results in a chronology of temporally and spatially varying freshwater fluxes from the Last Glacial Maximum to the present day. We analyse the dependence of the runoff routing to grid resolution and parameters of the isostatic adjustment module of the ice sheet model.

  12. A dynamic continental runoff routing model applied to the last Northern Hemisphere deglaciation

    Directory of Open Access Journals (Sweden)

    H. Goelzer

    2012-05-01

    Full Text Available We describe and evaluate a dynamical continental runoff routing model for the Northern Hemisphere that calculates the runoff pathways in response to topographic modifications due to changes in ice thickness and isostatic adjustment. The algorithm is based on the steepest gradient method and takes as simplifying assumption that depressions are filled at all times and water drains through the lowest outlet points. It also considers changes in water storage and lake drainage in post-processing mode that become important in the presence of large ice dammed proglacial lakes. Although applicable to other scenarios as well, the model was conceived to study the routing of freshwater fluxes during the last Northern Hemisphere deglaciation. For that specific application we simulated the Northern Hemisphere ice sheets with an existing 3-D thermomechanical ice sheet model, which calculates changes in topography due to changes in ice cover and isostatic adjustment, as well as the evolution of freshwater fluxes resulting from surface ablation, iceberg calving and basal melt. The continental runoff model takes this input, calculates the drainage pathways and routes the freshwater fluxes to the surface grid points of an existing ocean model. This results in a chronology of temporally and spatially varying freshwater fluxes from the Last Glacial Maximum to the present day. We analyse the dependence of the runoff routing to grid resolution and parameters of the isostatic adjustment module of the ice sheet model.

  13. Climatic and Landscape Controls on Storage Capacity of Urban Stormwater Control Measures (SCMs): Implications for Stormwater-Stream Connectivity

    Science.gov (United States)

    Fanelli, R. M.; Prestegaard, K. L.; Palmer, M.

    2015-12-01

    Urbanization alters watershed hydrological processes; impervious surfaces increase runoff generation, while storm sewer networks increase connectivity between runoff sources and streams. Stormwater control measures (SCMs) that enhance stormwater infiltration have been proposed to mitigate these effects by functioning as stormwater sinks. Regenerative stormwater conveyances structures (RSCs) are an example of infiltration-based SCMs that are placed between storm sewer outfalls and perennial stream networks. Given their location, RSCs act as critical nodes that regulate stormwater-stream connectivity. Therefore, the storage capacity of a RSC structure may exert a major control on the frequency, duration, and magnitude of these connections. This project examined both hydrogeological and hydro-climatic factors that could influence storage capacity of RSC structures. We selected three headwater (5-48 ha) urban watersheds near Annapolis, Maryland, USA. Each watershed is drained by first-order perennial streams and has been implemented with a RSC structure. We conducted high-frequency precipitation and stream stage monitoring below the outlet of each RSC structure for a 1-year period. We also instrumented one of the RSC structures with groundwater wells to monitor changes in subsurface storage over time. Using these data, we 1) identified rainfall thresholds for RSC storage capacity exceedance; 2) quantified the frequency and duration of connectivity when the storage capacity of each RSC was exceeded; and 3) evaluated both event-scale and seasonal changes in groundwater levels within the RSC structure. Precipitation characteristics and antecedent precipitation indices influenced the frequency and duration of stormwater-stream connections. We hypothesize both infiltration limitations and storage limitations of the RSCs contributed to the temporal patterns we observed in stormwater-stream connectivity. We also observed reduced storage potential as contributing area and

  14. A multi basin SWAT model analysis of runoff and sedimentation in the Blue Nile, Ethiopia

    Directory of Open Access Journals (Sweden)

    Z. M. Easton

    2010-10-01

    Full Text Available A multi basin analysis of runoff and erosion in the Blue Nile Basin, Ethiopia was conducted to elucidate sources of runoff and sediment. Erosion is arguably the most critical problem in the Blue Nile Basin, as it limits agricultural productivity in Ethiopia, degrades benthos in the Nile, and results in sedimentation of dams in downstream countries. A modified version of the Soil and Water Assessment Tool (SWAT model was developed to predict runoff and sediment losses from the Ethiopian Blue Nile Basin. The model simulates saturation excess runoff from the landscape using a simple daily water balance coupled to a topographic wetness index in ways that are consistent with observed runoff processes in the basin. The spatial distribution of landscape erosion is thus simulated more correctly. The model was parameterized in a nested design for flow at eight and sediment at three locations in the basin. Subbasins ranged in size from 1.3 to 174 000 km2, and interestingly, the partitioning of runoff and infiltrating flow could be predicted by topographic information. Model predictions showed reasonable accuracy (Nash Sutcliffe Efficiencies ranged from 0.53–0.92 with measured data across all sites except Kessie, where the water budget could not be closed; however, the timing of flow was well captured. Runoff losses increased with rainfall during the monsoonal season and were greatest from areas with shallow soils and large contributing areas. Analysis of model results indicate that upland landscape erosion dominated sediment delivery to the main stem of the Blue Nile in the early part of the growing season when tillage occurs and before the soil was wetted up and plant cover was established. Once plant cover was established in mid August landscape erosion was negligible and sediment export was dominated by channel processes and re-suspension of landscape sediment deposited early in the growing season. These results imply that targeting small

  15. Rainfall–Runoff Simulations to Assess the Potential of SuDS for Mitigating Flooding in Highly Urbanized Catchments

    Directory of Open Access Journals (Sweden)

    Daniel Jato-Espino

    2016-01-01

    Full Text Available Sustainable Urban Drainage Systems (SuDS constitute an alternative to conventional drainage when managing stormwater in cities, reducing the impact of urbanization by decreasing the amount of runoff generated by a rainfall event. This paper shows the potential benefits of installing different types of SuDS in preventing flooding in comparison with the common urban drainage strategies consisting of sewer networks of manholes and pipes. The impact of these systems on urban water was studied using Geographic Information Systems (GIS, which are useful tools when both delineating catchments and parameterizing the elements that define a stormwater drainage system. Taking these GIS-based data as inputs, a series of rainfall–runoff simulations were run in a real catchment located in the city of Donostia (Northern Spain using stormwater computer models, in order to compare the flow rates and depths produced by a design storm before and after installing SuDS. The proposed methodology overcomes the lack of precision found in former GIS-based stormwater approaches when dealing with the modeling of highly urbanized catchments, while the results demonstrated the usefulness of these systems in reducing the volume of water generated after a rainfall event and their ability to prevent localized flooding and surcharges along the sewer network.

  16. Rainfall-Runoff Simulations to Assess the Potential of SuDS for Mitigating Flooding in Highly Urbanized Catchments.

    Science.gov (United States)

    Jato-Espino, Daniel; Charlesworth, Susanne M; Bayon, Joseba R; Warwick, Frank

    2016-01-21

    Sustainable Urban Drainage Systems (SuDS) constitute an alternative to conventional drainage when managing stormwater in cities, reducing the impact of urbanization by decreasing the amount of runoff generated by a rainfall event. This paper shows the potential benefits of installing different types of SuDS in preventing flooding in comparison with the common urban drainage strategies consisting of sewer networks of manholes and pipes. The impact of these systems on urban water was studied using Geographic Information Systems (GIS), which are useful tools when both delineating catchments and parameterizing the elements that define a stormwater drainage system. Taking these GIS-based data as inputs, a series of rainfall-runoff simulations were run in a real catchment located in the city of Donostia (Northern Spain) using stormwater computer models, in order to compare the flow rates and depths produced by a design storm before and after installing SuDS. The proposed methodology overcomes the lack of precision found in former GIS-based stormwater approaches when dealing with the modeling of highly urbanized catchments, while the results demonstrated the usefulness of these systems in reducing the volume of water generated after a rainfall event and their ability to prevent localized flooding and surcharges along the sewer network.

  17. Rainfall–Runoff Simulations to Assess the Potential of SuDS for Mitigating Flooding in Highly Urbanized Catchments

    Science.gov (United States)

    Jato-Espino, Daniel; Charlesworth, Susanne M.; Bayon, Joseba R.; Warwick, Frank

    2016-01-01

    Sustainable Urban Drainage Systems (SuDS) constitute an alternative to conventional drainage when managing stormwater in cities, reducing the impact of urbanization by decreasing the amount of runoff generated by a rainfall event. This paper shows the potential benefits of installing different types of SuDS in preventing flooding in comparison with the common urban drainage strategies consisting of sewer networks of manholes and pipes. The impact of these systems on urban water was studied using Geographic Information Systems (GIS), which are useful tools when both delineating catchments and parameterizing the elements that define a stormwater drainage system. Taking these GIS-based data as inputs, a series of rainfall–runoff simulations were run in a real catchment located in the city of Donostia (Northern Spain) using stormwater computer models, in order to compare the flow rates and depths produced by a design storm before and after installing SuDS. The proposed methodology overcomes the lack of precision found in former GIS-based stormwater approaches when dealing with the modeling of highly urbanized catchments, while the results demonstrated the usefulness of these systems in reducing the volume of water generated after a rainfall event and their ability to prevent localized flooding and surcharges along the sewer network. PMID:26805864

  18. Simulating pesticide transport in urbanized catchments: a new spatially-distributed dynamic pesticide runoff model

    Science.gov (United States)

    Tang, Ting; Seuntjens, Piet; van Griensven, Ann; Bronders, Jan

    2016-04-01

    Urban areas can significantly contribute to pesticide contamination in surface water. However, pesticide behaviours in urban areas, particularly on hard surfaces, are far less studied than those in agricultural areas. Pesticide application on hard surfaces (e.g. roadsides and walkways) is of particular concern due to the high imperviousness and therefore high pesticide runoff potential. Experimental studies have shown that pesticide behaviours on and interactions with hard surfaces are important factors controlling the pesticide runoff potential, and therefore the magnitude and timing of peak concentrations in surface water. We conceptualized pesticide behaviours on hard surfaces and incorporated the conceptualization into a new pesticide runoff model. The pesticide runoff model was implemented in a catchment hydrological model WetSpa-Python (Water and Energy Transfer between Soil, Plants and Atmosphere, Python version). The conceptualization for pesticide processes on hard surfaces accounts for the differences in pesticide behaviour on different hard surfaces. Four parameters are used to describe the partitioning and wash-off of each pesticide on hard surfaces. We tested the conceptualization using experimental dataset for five pesticides on two types of hard surfaces, namely concrete and asphalt. The conceptualization gave good performance in accounting for the wash-off pattern for the modelled pesticides and surfaces, according to quantitative evaluations using the Nash-Sutcliffe efficiency and percent bias. The resulting pesticide runoff model WetSpa-PST (WetSpa for PeSTicides) can simulate pesticides and their metabolites at the catchment scale. Overall, it includes four groups of pesticide processes, namely pesticide application, pesticide interception by plant foliage, pesticide processes on land surfaces (including partitioning, degradation and wash-off on hard surface; partitioning, dissipation, infiltration and runoff in soil) and pesticide processes in

  19. Comparative evaluation of runoff and water quality using HSPF and SWMM.

    Science.gov (United States)

    Lee, Sae-Bom; Yoon, Chun-Gyeong; Jung, Kwang Wook; Hwang, Ha Sun

    2010-01-01

    Stormwater pollution is the untreated contaminated water that drains into natural waterways from land uses within an urban catchment. Several studies have demonstrated the deterioration of water quality in receiving bodies of water caused by stormwater runoff. The data have reported that urban runoff play primary roles in degrading water quality in adjacent aquatic systems. The accurate estimation of non-pollutant loads from urban runoff and the prediction of water quality in receiving waters are important. The objective of this paper is to assess the applicability of the watershed scale hydrologic and water quality simulation models SWMM and HSPF to simulate the hydrology of a small watershed in the Han River Basin. Monitoring was performed in small scale watersheds, which is homogeneous land use. The applicability of SWMM and HSPF model was examined for small watersheds using hourly monitoring data. The results of SWMM were reasonably reflected with observed data in small scale urban area. HSPF model was effective at specifying parameters related to runoff and water quality when using hourly monitoring data. The watershed models used in this study adequately simulated watershed characteristics and are recommended to support watershed management.

  20. Comparison of several climate indices as inputs in modelling of the Baltic Sea runoff

    Energy Technology Data Exchange (ETDEWEB)

    Hanninen, J.; Vuorinen, I. [Turku Univ. (Finland). Archipelaco Research Inst.], e-mail: jari.hanninen@utu.fi

    2012-11-01

    Using Transfer function (TF) models, we have earlier presented a chain of events between changes in the North Atlantic Oscillation (NAO) and their oceanographical and ecological consequences in the Baltic Sea. Here we tested whether other climate indices as inputs would improve TF models, and our understanding of the Baltic Sea ecosystem. Besides NAO, the predictors were the Arctic Oscillation (AO), sea-level air pressures at Iceland (SLP), and wind speeds at Hoburg (Gotland). All indices produced good TF models when the total riverine runoff to the Baltic Sea was used as a modelling basis. AO was not applicable in all study areas, showing a delay of about half a year between climate and runoff events, connected with freezing and melting time of ice and snow in the northern catchment area of the Baltic Sea. NAO appeared to be most useful modelling tool as its area of applicability was the widest of the tested indices, and the time lag between climate and runoff events was the shortest. SLP and Hoburg wind speeds showed largely same results as NAO, but with smaller areal applicability. Thus AO and NAO were both mostly contributing to the general understanding of climate control of runoff events in the Baltic Sea ecosystem. (orig.)

  1. Chlorpyrifos and atrazine removal from runoff by vegetated filter strips: experiments and predictive modeling.

    Science.gov (United States)

    Poletika, N N; Coody, P N; Fox, G A; Sabbagh, G J; Dolder, S C; White, J

    2009-01-01

    Runoff volume and flow concentration are hydrological factors that limit effectiveness of vegetated filter strips (VFS) in removing pesticides from surface runoff. Empirical equations that predict VFS pesticide effectiveness based solely on physical characteristics are insufficient on the event scale because they do not completely account for hydrological processes. This research investigated the effect of drainage area ratio (i.e., the ratio of field area to VFS area) and flow concentration (i.e., uniform versus concentrated flow) on pesticide removal efficiency of a VFS and used these data to provide further field verification of a recently proposed numerical/empirical modeling procedure for predicting removal efficiency under variable flow conditions. Runoff volumes were used to simulate drainage area ratios of 15:1 and 30:1. Flow concentration was investigated based on size of the VFS by applying artificial runoff to 10% of the plot width (i.e., concentrated flow) or the full plot width (i.e., uniform flow). Artificial runoff was metered into 4.6-m long VFS plots for 90 min after a simulated rainfall of 63 mm applied over 2 h. The artificial runoff contained sediment and was dosed with chlorpyrifos and atrazine. Pesticide removal efficiency of VFS for uniform flow conditions (59% infiltration; 88% sediment removal) was 85% for chlorpyrifos and 62% for atrazine. Flow concentration reduced removal efficiencies regardless of drainage area ratio (i.e., 16% infiltration, 31% sediment removal, 21% chlorpyrifos removal, and 12% atrazine removal). Without calibration, the predictive modeling based on the integrated VFSMOD and empirical hydrologic-based pesticide trapping efficiency equation predicted atrazine and chlorpyrifos removal efficiency under uniform and concentrated flow conditions. Consideration for hydrological processes, as opposed to statistical relationships based on buffer physical characteristics, is required to adequately predict VFS pesticide trapping

  2. Modelling urban rainfall-runoff responses using an experimental, two-tiered physical modelling environment

    Science.gov (United States)

    Green, Daniel; Pattison, Ian; Yu, Dapeng

    2016-04-01

    Surface water (pluvial) flooding occurs when rainwater from intense precipitation events is unable to infiltrate into the subsurface or drain via natural or artificial drainage channels. Surface water flooding poses a serious hazard to urban areas across the world, with the UK's perceived risk appearing to have increased in recent years due to surface water flood events seeming more severe and frequent. Surface water flood risk currently accounts for 1/3 of all UK flood risk, with approximately two million people living in urban areas at risk of a 1 in 200-year flood event. Research often focuses upon using numerical modelling techniques to understand the extent, depth and severity of actual or hypothetical flood scenarios. Although much research has been conducted using numerical modelling, field data available for model calibration and validation is limited due to the complexities associated with data collection in surface water flood conditions. Ultimately, the data which numerical models are based upon is often erroneous and inconclusive. Physical models offer a novel, alternative and innovative environment to collect data within, creating a controlled, closed system where independent variables can be altered independently to investigate cause and effect relationships. A physical modelling environment provides a suitable platform to investigate rainfall-runoff processes occurring within an urban catchment. Despite this, physical modelling approaches are seldom used in surface water flooding research. Scaled laboratory experiments using a 9m2, two-tiered 1:100 physical model consisting of: (i) a low-cost rainfall simulator component able to simulate consistent, uniformly distributed (>75% CUC) rainfall events of varying intensity, and; (ii) a fully interchangeable, modular plot surface have been conducted to investigate and quantify the influence of a number of terrestrial and meteorological factors on overland flow and rainfall-runoff patterns within a modelled

  3. Multiobjective training of artificial neural networks for rainfall-runoff modeling

    NARCIS (Netherlands)

    De Vos, N.J.; Rientjes, T.H.M.

    2008-01-01

    This paper presents results on the application of various optimization algorithms for the training of artificial neural network rainfall-runoff models. Multilayered feed-forward networks for forecasting discharge from two mesoscale catchments in different climatic regions have been developed for thi

  4. Multiobjective training of artificial neural networks for rainfall-runoff modeling

    NARCIS (Netherlands)

    De Vos, N.J.; Rientjes, T.H.M.

    2008-01-01

    This paper presents results on the application of various optimization algorithms for the training of artificial neural network rainfall-runoff models. Multilayered feed-forward networks for forecasting discharge from two mesoscale catchments in different climatic regions have been developed for

  5. Impacts of Noah model physics on catchment-scale runoff simulations

    NARCIS (Netherlands)

    Zheng, D.; Velde, van der R.; Su, Z.; Wen, J.; Wang, X.; Booij, M.J.; Hoekstra, A.Y.; Lv, S.; Ek, M.B.

    2016-01-01

    Noah model physics options validated for the source region of the Yellow River (SRYR) are applied to investigate their ability in reproducing runoff at the catchment scale. Three sets of augmentations are implemented affecting descriptions of (i) turbulent and soil heat transport (Noah-H), (ii) soil

  6. Calibrating a Rainfall-Runoff and Routing Model for the Continental United States

    Science.gov (United States)

    Jankowfsky, S.; Li, S.; Assteerawatt, A.; Tillmanns, S.; Hilberts, A.

    2014-12-01

    Catastrophe risk models are widely used in the insurance industry to estimate the cost of risk. The models consist of hazard models linked to vulnerability and financial loss models. In flood risk models, the hazard model generates inundation maps. In order to develop country wide inundation maps for different return periods a rainfall-runoff and routing model is run using stochastic rainfall data. The simulated discharge and runoff is then input to a two dimensional inundation model, which produces the flood maps. In order to get realistic flood maps, the rainfall-runoff and routing models have to be calibrated with observed discharge data. The rainfall-runoff model applied here is a semi-distributed model based on the Topmodel (Beven and Kirkby, 1979) approach which includes additional snowmelt and evapotranspiration models. The routing model is based on the Muskingum-Cunge (Cunge, 1969) approach and includes the simulation of lakes and reservoirs using the linear reservoir approach. Both models were calibrated using the multiobjective NSGA-II (Deb et al., 2002) genetic algorithm with NLDAS forcing data and around 4500 USGS discharge gauges for the period from 1979-2013. Additional gauges having no data after 1979 were calibrated using CPC rainfall data. The model performed well in wetter regions and shows the difficulty of simulating areas with sinks such as karstic areas or dry areas. Beven, K., Kirkby, M., 1979. A physically based, variable contributing area model of basin hydrology. Hydrol. Sci. Bull. 24 (1), 43-69. Cunge, J.A., 1969. On the subject of a flood propagation computation method (Muskingum method), J. Hydr. Research, 7(2), 205-230. Deb, K., Pratap, A., Agarwal, S., Meyarivan, T., 2002. A fast and elitist multiobjective genetic algorithm: NSGA-II, IEEE Transactions on evolutionary computation, 6(2), 182-197.

  7. The effect of GCM biases on global runoff simulations of a land surface model

    Science.gov (United States)

    Papadimitriou, Lamprini V.; Koutroulis, Aristeidis G.; Grillakis, Manolis G.; Tsanis, Ioannis K.

    2017-09-01

    Global climate model (GCM) outputs feature systematic biases that render them unsuitable for direct use by impact models, especially for hydrological studies. To deal with this issue, many bias correction techniques have been developed to adjust the modelled variables against observations, focusing mainly on precipitation and temperature. However, most state-of-the-art hydrological models require more forcing variables, in addition to precipitation and temperature, such as radiation, humidity, air pressure, and wind speed. The biases in these additional variables can hinder hydrological simulations, but the effect of the bias of each variable is unexplored. Here we examine the effect of GCM biases on historical runoff simulations for each forcing variable individually, using the JULES land surface model set up at the global scale. Based on the quantified effect, we assess which variables should be included in bias correction procedures. To this end, a partial correction bias assessment experiment is conducted, to test the effect of the biases of six climate variables from a set of three GCMs. The effect of the bias of each climate variable individually is quantified by comparing the changes in simulated runoff that correspond to the bias of each tested variable. A methodology for the classification of the effect of biases in four effect categories (ECs), based on the magnitude and sensitivity of runoff changes, is developed and applied. Our results show that, while globally the largest changes in modelled runoff are caused by precipitation and temperature biases, there are regions where runoff is substantially affected by and/or more sensitive to radiation and humidity. Global maps of bias ECs reveal the regions mostly affected by the bias of each variable. Based on our findings, for global-scale applications, bias correction of radiation and humidity, in addition to that of precipitation and temperature, is advised. Finer spatial-scale information is also provided

  8. Rainfall runoff modelling of the Upper Ganga and Brahmaputra basins using PERSiST.

    Science.gov (United States)

    Futter, M N; Whitehead, P G; Sarkar, S; Rodda, H; Crossman, J

    2015-06-01

    There are ongoing discussions about the appropriate level of complexity and sources of uncertainty in rainfall runoff models. Simulations for operational hydrology, flood forecasting or nutrient transport all warrant different levels of complexity in the modelling approach. More complex model structures are appropriate for simulations of land-cover dependent nutrient transport while more parsimonious model structures may be adequate for runoff simulation. The appropriate level of complexity is also dependent on data availability. Here, we use PERSiST; a simple, semi-distributed dynamic rainfall-runoff modelling toolkit to simulate flows in the Upper Ganges and Brahmaputra rivers. We present two sets of simulations driven by single time series of daily precipitation and temperature using simple (A) and complex (B) model structures based on uniform and hydrochemically relevant land covers respectively. Models were compared based on ensembles of Bayesian Information Criterion (BIC) statistics. Equifinality was observed for parameters but not for model structures. Model performance was better for the more complex (B) structural representations than for parsimonious model structures. The results show that structural uncertainty is more important than parameter uncertainty. The ensembles of BIC statistics suggested that neither structural representation was preferable in a statistical sense. Simulations presented here confirm that relatively simple models with limited data requirements can be used to credibly simulate flows and water balance components needed for nutrient flux modelling in large, data-poor basins.

  9. A current precipitation index-based model for continuous daily runoff simulation in seasonally snow covered sub-arctic catchments

    Science.gov (United States)

    Akanegbu, Justice O.; Marttila, Hannu; Ronkanen, Anna-Kaisa; Kløve, Bjørn

    2017-02-01

    A new precipitation index-based model, which includes a snow accumulation and melt component, has been developed to simulate hydrology in high latitude catchments. The model couples a point snowmelt model with a current precipitation index (CPI) formulation to simulate continuous daily runoff from catchments with seasonal snow cover. A new runoff conversion factor: CT and Lf, threshold flow factor ThQ and runoff transformation function Maxbas were introduced into the CPI equation, which converts and transforms the routed daily CPI into daily runoff and maintains the daily base flow in the catchment. The model was developed using twelve sub-arctic boreal catchments located above and below the Arctic Circle in northern Finland, representing a region with considerable seasonal snow cover. The results showed that the model can adequately simulate and produce the dynamics of daily runoff from catchments where the underlying physical conditions are not known. An open-access Excel-based model is provided with this paper for daily runoff simulations. The model can be used to estimate runoff in sub-arctic regions where little data is typically available but significant changes in climate are expected, with considerable shifts in the amount and timing of snowmelt and runoff.

  10. The application of an analytical probabilistic model for estimating the rainfall-runoff reductions achieved using a rainwater harvesting system.

    Science.gov (United States)

    Kim, Hyoungjun; Han, Mooyoung; Lee, Ju Young

    2012-05-01

    Rainwater harvesting systems cannot only supplement on-site water needs, but also reduce water runoff and lessen downstream flooding. In this study, an existing analytic model for estimating the runoff in urban areas is modified to provide a more economical and effective model that can be used for describing rainwater harvesting. This model calculates the rainfall-runoff reduction by taking into account the catchment, storage tank, and infiltration facility of a water harvesting system; this calculation is based on the water balance equation, and the cumulative distribution, probability density, and average rainfall-runoff functions. This model was applied to a water harvesting system at the Seoul National University in order to verify its practicality. The derived model was useful for evaluating runoff reduction and for designing the storage tank capacity.

  11. A tale of two rain gardens: Barriers and bridges to adaptive management of urban stormwater in Cleveland, Ohio

    Science.gov (United States)

    Green infrastructure installations such as rain gardens and bioswales are increasingly regarded as viable tools to mitigate stormwater runoff at the parcel level. The use of adaptive management to implement and monitor green infrastructure projects as experimental attempts to man...

  12. BMP analysis system for watershed-based stormwater management.

    Science.gov (United States)

    Zhen, Jenny; Shoemaker, Leslie; Riverson, John; Alvi, Khalid; Cheng, Mow-Soung

    2006-01-01

    Best Management Practices (BMPs) are measures for mitigating nonpoint source (NPS) pollution caused mainly by stormwater runoff. Established urban and newly developing areas must develop cost effective means for restoring or minimizing impacts, and planning future growth. Prince George's County in Maryland, USA, a fast-growing region in the Washington, DC metropolitan area, has developed a number of tools to support analysis and decision making for stormwater management planning and design at the watershed level. These tools support watershed analysis, innovative BMPs, and optimization. Application of these tools can help achieve environmental goals and lead to significant cost savings. This project includes software development that utilizes GIS information and technology, integrates BMP processes simulation models, and applies system optimization techniques for BMP planning and selection. The system employs the ESRI ArcGIS as the platform, and provides GIS-based visualization and support for developing networks including sequences of land uses, BMPs, and stream reaches. The system also provides interfaces for BMP placement, BMP attribute data input, and decision optimization management. The system includes a stand-alone BMP simulation and evaluation module, which complements both research and regulatory nonpoint source control assessment efforts, and allows flexibility in the examining various BMP design alternatives. Process based simulation of BMPs provides a technique that is sensitive to local climate and rainfall patterns. The system incorporates a meta-heuristic optimization technique to find the most cost-effective BMP placement and implementation plan given a control target, or a fixed cost. A case study is presented to demonstrate the application of the Prince George's County system. The case study involves a highly urbanized area in the Anacostia River (a tributary to Potomac River) watershed southeast of Washington, DC. An innovative system of

  13. Modeling rainfall-runoff processes using smoothed particle hydrodynamics with mass-varied particles

    Science.gov (United States)

    Chang, Tsang-Jung; Chang, Yu-Sheng; Chang, Kao-Hua

    2016-12-01

    In this study, a novel treatment of adopting mass-varied particles in smoothed particle hydrodynamics (SPH) is proposed to solve the shallow water equations (SWEs) and model the rainfall-runoff process. Since SWEs have depth-averaged or cross-section-averaged features, there is no sufficient dimension to add rainfall particles. Thus, SPH-SWE methods have focused on modeling discharge flows in open channels or floodplains without rainfall. With the proposed treatment, the application of SPH-SWEs can be extended to rainfall-runoff processes in watersheds. First, the numerical procedures associated with using mass-varied particles in SPH-SWEs are introduced and derived. Then, numerical validations are conducted for three benchmark problems, including uniform rainfall over a 1D flat sloping channel, nonuniform rain falling over a 1D three-slope channel with different rainfall durations, and uniform rainfall over a 2D plot with complex topography. The simulated results indicate that the proposed treatment can avoid the necessity of a source term function of mass variation, and no additional particles are needed for the increase of mass. Rainfall-runoff processes can be well captured in the presence of hydraulic jumps, dry/wet bed flows, and supercritical/subcritical/transcritical flows. The proposed treatment using mass-varied particles was proven robust and reliable for modeling rainfall-runoff processes. It can provide a new alternative for investigating practical hydrological problems.

  14. Extending a rainfall-runoff model for lowland catchments from lumped to semi-distributed

    Science.gov (United States)

    Brauer, Claudia; Torfs, Paul; Teuling, Ryan; Uijlenhoet, Remko

    2016-04-01

    The Wageningen Lowland Runoff Simulator (WALRUS) is a parametric rainfall-runoff model for catchments with shallow groundwater (Brauer et al., 2014ab). WALRUS was developed using data and experience from two Dutch experimental catchments: the Hupsel Brook catchment (6.5 km2) and the Cabauw polder (0.5 km2). We identified key processes for runoff generation in lowland catchments, notably (1) groundwater-unsaturated zone coupling, (2) wetness-dependent flow routes, (3) groundwater-surface water feedbacks and (4) seepage and surface water supply, and accounted for these in the model structure. Up to now, WALRUS has been used in a lumped manner. However, water managers and researchers have expressed an interest in a semi-distributed version for application to larger catchments with varying forcing and catchment characteristics and to investigate the effect of groundwater flow within the catchment on modelled variables (e.g. groundwater depth). We combined WALRUS and a model for 2-dimensional groundwater flow into a simple modelling framework. WALRUS was already designed to cope with groundwater flow into or out of the model domain, because seepage and lateral groundwater flow are common in lowlands. In the semi-distributed version, we used this feature to couple different WALRUS elements (grid cells or subcatchments) to each other. Groundwater flow was computed using a digital elevation model, groundwater depths computed by WALRUS, soil transmissivity data and Darcy's law. Finally, we implemented a surface routing model including backwater effects, which are relevant in areas with little relief. With respect to the lumped version, the semi-distributed requires more data. Therefore, we investigated the added value of different data sources (forcing, elevation, soil, surface water) separately. We will present the rationale behind the semi-distributed model and show how the model structure compares to observations and and simulations without lateral transport. C.C. Brauer

  15. GEOGRAPHICAL INFORMATION SYSTEM, DECISION SUPPORT SYSTEMS, AND URBAN STORMWATER MANAGEMENT

    Science.gov (United States)

    The full report reviews the application of Geographic Inforamtion System (GIS) technology to the field of urban stormwater modeling. The GIS literature is reviewed in the context of its use as a spatial database for urban stormwater modeling, integration of GIS and hydroloic time...

  16. Estimation of parameters in a distributed precipitation-runoff model for Norway

    OpenAIRE

    Beldring, S.; Engeland, K; Roald, L. A.; Sælthun, N. R.; A. Voksø

    2003-01-01

    A distributed version of the HBV-model using 1 km2 grid cells and daily time step was used to simulate runoff from the entire land surface of Norway for the period 1961-1990. The model was sensitive to changes in small scale properties of the land surface and the climatic input data, through explicit representation of differences between model elements, and by implicit consideration of sub-grid variations in moisture status. A geogra...

  17. The role of observation uncertainty in the calibration of hydrologic rainfall-runoff models

    Directory of Open Access Journals (Sweden)

    T. Ghizzoni

    2007-06-01

    Full Text Available Hydrologic rainfall-runoff models are usually calibrated with reference to a limited number of recorded flood events, for which rainfall and runoff measurements are available. In this framework, model's parameters consistency depends on the number of both events and hydrograph points used for calibration, and on measurements reliability. Recently, to make users aware of application limits, major attention has been devoted to the estimation of uncertainty in hydrologic modelling. Here a simple numerical experiment is proposed, that allows the analysis of uncertainty in hydrologic rainfall-runoff modelling associated to both quantity and quality of available data.

    A distributed rainfall-runoff model based on geomorphologic concepts has been used. The experiment involves the analysis of an ensemble of model runs, and its overall set up holds if the model is to be applied in different catchments and climates, or even if a different hydrologic model is used. With reference to a set of 100 synthetic rainfall events characterized by a given rainfall volume, the effect of uncertainty in parameters calibration is studied. An artificial truth – perfect observation – is created by using the model in a known configuration. An external source of uncertainty is introduced by assuming realistic, i.e. uncertain, discharge observations to calibrate the model. The range of parameters' values able to "reproduce" the observation is studied. Finally, the model uncertainty is evaluated and discussed. The experiment gives useful indications about the number of both events and data points needed for a careful and stable calibration of a specific model, applied in a given climate and catchment. Moreover, an insight on the expected and maximum error in flood peak discharge simulations is given: errors ranging up to 40% are to be expected if parameters are calibrated on insufficient data sets.

  18. Loss Modeling with a Data-Driven Approach in Event-Based Rainfall-Runoff Analysis

    Science.gov (United States)

    Chua, L. H. C.

    2012-04-01

    Mathematical models require the estimation of rainfall abstractions for accurate predictions of runoff. Although loss models such as the constant loss and exponential loss models are commonly used, these methods are based on simplified assumptions of the physical process. A new approach based on the data driven paradigm to estimate rainfall abstractions is proposed in this paper. The proposed data driven model, based on the artificial neural network (ANN) does not make any assumptions on the loss behavior. The estimated discharge from a physically-based model, obtained from the kinematic wave (KW) model assuming zero losses, was used as the only input to the ANN. The output is the measured discharge. Thus, the ANN functions as a black-box loss model. Two sets of data were analyzed for this study. The first dataset consists of rainfall and runoff data, measured from an artificial catchment (area = 25 m2) comprising two overland planes (slope = 11%), 25m long, transversely inclined towards a rectangular channel (slope = 2%) which conveyed the flow, recorded using calibrated weigh tanks, to the outlet. Two rain gauges, each placed 6.25 m from either ends of the channel, were used to record rainfall. Data for six storm events over the period between October 2002 and December 2002 were analyzed. The second dataset was obtained from the Upper Bukit Timah catchment (area = 6.4 km2) instrumented with two rain gauges and a flow measuring station. A total of six events recorded between November 1987 and July 1988 were selected for this study. The runoff predicted by the ANN was compared with the measured runoff. In addition, results from KW models developed for both the catchments were used as a benchmark. The KW models were calibrated assuming the loss rate for an average event for each of the datasets. The results from both the ANN and KW models agreed well with the runoff measured from the artificial catchment. The KW model is expected to perform well since the catchment

  19. Characterization of chromium species in urban runoff

    DEFF Research Database (Denmark)

    Cederkvist, Karin; Jensen, Marina Bergen; Holm, Peter Engelund

    2013-01-01

    Little is known about the presence of the element Cr in its toxic hexavalent form Cr(VI) in stormwater runoff from urban areas. Most studies report only total Cr concentration, i.e., including also the nontoxic Cr(III) molecular form. The objective of this study was to evaluate a field method bas...

  20. Highway runoff quality models for the protection of environmentally sensitive areas

    Science.gov (United States)

    Trenouth, William R.; Gharabaghi, Bahram

    2016-11-01

    This paper presents novel highway runoff quality models using artificial neural networks (ANN) which take into account site-specific highway traffic and seasonal storm event meteorological factors to predict the event mean concentration (EMC) statistics and mean daily unit area load (MDUAL) statistics of common highway pollutants for the design of roadside ditch treatment systems (RDTS) to protect sensitive receiving environs. A dataset of 940 monitored highway runoff events from fourteen sites located in five countries (Canada, USA, Australia, New Zealand, and China) was compiled and used to develop ANN models for the prediction of highway runoff suspended solids (TSS) seasonal EMC statistical distribution parameters, as well as the MDUAL statistics for four different heavy metal species (Cu, Zn, Cr and Pb). TSS EMCs are needed to estimate the minimum required removal efficiency of the RDTS needed in order to improve highway runoff quality to meet applicable standards and MDUALs are needed to calculate the minimum required capacity of the RDTS to ensure performance longevity.

  1. Redox Dynamics and Oxygen Reduction Rates of Infiltrating Urban Stormwater beneath Low Impact Development (LID)

    OpenAIRE

    Mays N. Danfoura; Gurdak, Jason J.

    2016-01-01

    Low impact development (LID) best management practices (BMPs) collect, infiltrate, and treat stormwater runoff, and increase recharge to aquifers. Understanding the controls on reduction/oxidation (redox) conditions within LID BMPs is important for groundwater management because outflow from some LID BMPs can recharge aquifers and affect groundwater quality. Here we evaluate redox conditions of urban stormwater runoff in a LID infiltration trench in San Francisco, California, and quantify the re...

  2. Adjustment of rainfall estimates from weather radars using in-situ stormwater drainage sensors

    DEFF Research Database (Denmark)

    Ahm, Malte

    importance as long as the estimated flow and water levels are correct. It makes sense to investigate the possibility of adjusting weather radar data to rainfall-runoff measurements instead of rain gauge measurements in order to obtain better predictions of flow and water levels. This Ph.D. study investigates......The topic of this Ph.D. thesis is adjustment of weather radar rainfall measurements for urban drainage applications by the use of in-situ stormwater runoff measurements. It is possible to obtain the high spatiotemporal resolution rainfall data desired for advanced distributed urban drainage...... applications by the use of weather radars. Rainfall data representing the spatiotemporal distribution is a necessity for accurate modelling and real-time control of distributed urban drainage systems. Weather radar measurements are indirect measurements of the rainfall in the atmosphere, which poses some...

  3. Spatial sensitivity analysis of snow cover data in a distributed rainfall-runoff model

    Science.gov (United States)

    Berezowski, T.; Nossent, J.; Chormański, J.; Batelaan, O.

    2015-04-01

    As the availability of spatially distributed data sets for distributed rainfall-runoff modelling is strongly increasing, more attention should be paid to the influence of the quality of the data on the calibration. While a lot of progress has been made on using distributed data in simulations of hydrological models, sensitivity of spatial data with respect to model results is not well understood. In this paper we develop a spatial sensitivity analysis method for spatial input data (snow cover fraction - SCF) for a distributed rainfall-runoff model to investigate when the model is differently subjected to SCF uncertainty in different zones of the model. The analysis was focussed on the relation between the SCF sensitivity and the physical and spatial parameters and processes of a distributed rainfall-runoff model. The methodology is tested for the Biebrza River catchment, Poland, for which a distributed WetSpa model is set up to simulate 2 years of daily runoff. The sensitivity analysis uses the Latin-Hypercube One-factor-At-a-Time (LH-OAT) algorithm, which employs different response functions for each spatial parameter representing a 4 × 4 km snow zone. The results show that the spatial patterns of sensitivity can be easily interpreted by co-occurrence of different environmental factors such as geomorphology, soil texture, land use, precipitation and temperature. Moreover, the spatial pattern of sensitivity under different response functions is related to different spatial parameters and physical processes. The results clearly show that the LH-OAT algorithm is suitable for our spatial sensitivity analysis approach and that the SCF is spatially sensitive in the WetSpa model. The developed method can be easily applied to other models and other spatial data.

  4. Green roof stormwater retention: effects of roof surface, slope, and media depth.

    Science.gov (United States)

    VanWoert, Nicholaus D; Rowe, D Bradley; Andresen, Jeffrey A; Rugh, Clayton L; Fernandez, R Thomas; Xiao, Lan

    2005-01-01

    Urban areas generate considerably more stormwater runoff than natural areas of the same size due to a greater percentage of impervious surfaces that impede water infiltration. Roof surfaces account for a large portion of this impervious cover. Establishing vegetation on rooftops, known as green roofs, is one method of recovering lost green space that can aid in mitigating stormwater runoff. Two studies were performed using several roof platforms to quantify the effects of various treatments on stormwater retention. The first study used three different roof surface treatments to quantify differences in stormwater retention of a standard commercial roof with gravel ballast, an extensive green roof system without vegetation, and a typical extensive green roof with vegetation. Overall, mean percent rainfall retention ranged from 48.7% (gravel) to 82.8% (vegetated). The second study tested the influence of roof slope (2 and 6.5%) and green roof media depth (2.5, 4.0, and 6.0 cm) on stormwater retention. For all combined rain events, platforms at 2% slope with a 4-cm media depth had the greatest mean retention, 87%, although the difference from the other treatments was minimal. The combination of reduced slope and deeper media clearly reduced the total quantity of runoff. For both studies, vegetated green roof systems not only reduced the amount of stormwater runoff, they also extended its duration over a period of time beyond the actual rain event.

  5. The impacts of assimilating satellite soil moisture into a rainfall-runoff model in a semi-arid catchment

    Science.gov (United States)

    Soil moisture plays a key role in runoff generation processes. As a result, the assimilation of soil moisture observations into rainfall-runoff models is increasingly being investigated. Given the scarcity of ground-based in situ measurements, satellite soil moisture observations offer a valuable da...

  6. WEPP and ANN models for simulating soil loss and runoff in a semi-arid Mediterranean region.

    Science.gov (United States)

    Albaradeyia, Issa; Hani, Azzedine; Shahrour, Isam

    2011-09-01

    This paper presents the use of both the Water Erosion Prediction Project (WEPP) and the artificial neural network (ANN) for the prediction of runoff and soil loss in the central highland mountainous of the Palestinian territories. Analyses show that the soil erosion is highly dependent on both the rainfall depth and the rainfall event duration rather than on the rainfall intensity as mostly mentioned in the literature. The results obtained from the WEPP model for the soil loss and runoff disagree with the field data. The WEPP underestimates both the runoff and soil loss. Analyses conducted with the ANN agree well with the observation. In addition, the global network models developed using the data of all the land use type show a relatively unbiased estimation for both runoff and soil loss. The study showed that the ANN model could be used as a management tool for predicting runoff and soil loss.

  7. The sensitivity of catchment runoff models to rainfall data at different spatial scales

    Directory of Open Access Journals (Sweden)

    V. A. Bell

    2000-01-01

    Full Text Available The sensitivity of catchment runoff models to rainfall is investigated at a variety of spatial scales using data from a dense raingauge network and weather radar. These data form part of the HYREX (HYdrological Radar EXperiment dataset. They encompass records from 49 raingauges over the 135 km2 Brue catchment in south-west England together with 2 and 5 km grid-square radar data. Separate rainfall time-series for the radar and raingauge data are constructed on 2, 5 and 10 km grids, and as catchment average values, at a 15 minute time-step. The sensitivity of the catchment runoff models to these grid scales of input data is evaluated on selected convective and stratiform rainfall events. Each rainfall time-series is used to produce an ensemble of modelled hydrographs in order to investigate this sensitivity. The distributed model is shown to be sensitive to the locations of the raingauges within the catchment and hence to the spatial variability of rainfall over the catchment. Runoff sensitivity is strongest during convective rainfall when a broader spread of modelled hydrographs results, with twice the variability of that arising from stratiform rain. Sensitivity to rainfall data and model resolution is explored and, surprisingly, best performance is obtained using a lower resolution of rainfall data and model. Results from the distributed catchment model, the Simple Grid Model, are compared with those obtained from a lumped model, the PDM. Performance from the distributed model is found to be only marginally better during stratiform rain (R2 of 0.922 compared to 0.911 but significantly better during convective rain (R2 of 0.953 compared to 0.909. The improved performance from the distributed model can, in part, be accredited to the excellence of the dense raingauge network which would not be the norm for operational flood warning systems. In the final part of the paper, the effect of rainfall resolution on the performance of the 2 km distributed

  8. Assessment of rainfall-runoff modelling for climate change mitigation

    Science.gov (United States)

    Otieno, Hesbon; Han, Dawei; Woods, Ross

    2015-04-01

    Sustainable water resources management requires reliable methods for quantification of hydrological variables. This is a big challenge in developing countries, due to the problem of inadequate data as a result of sparse gauge networks. Successive occurrence of both abundance and shortage of water can arise in a catchment within the same year, with deficit situations becoming an increasingly occurring phenomenon in Kenya. This work compares the performance of two models in the Tana River catchment in Kenya, in generation of synthetic flow data. One of the models is the simpler USGS Thornthwaite monthly water balance model that uses a monthly time step and has three parameters. In order to explore alternative modelling schemes, the more complex Pitman model with 19 parameters was also applied in the catchment. It is uncertain whether the complex model (Pitman) will do better than the simple model, because a model with a large number of parameters may do well in the current system but poorly in future. To check this we have used old data (1970-1985) to calibrate the models and to validate with recent data (after 1985) to see which model is robust over time. This study is relevant and useful to water resources managers in scenario analysis for water resources management, planning and development in African countries with similar climates and catchment conditions.

  9. Spatial sensitivity analysis of snow cover data in a distributed rainfall–runoff model

    Directory of Open Access Journals (Sweden)

    T. Berezowski

    2014-10-01

    Full Text Available As the availability of spatially distributed data sets for distributed rainfall–runoff modelling is strongly growing, more attention should be paid to the influence of the quality of the data on the calibration. While a lot of progress has been made on using distributed data in simulations of hydrological models, sensitivity of spatial data with respect to model results is not well understood. In this paper we develop a spatial sensitivity analysis (SA method for snow cover fraction input data (SCF for a distributed rainfall–runoff model to investigate if the model is differently subjected to SCF uncertainty in different zones of the model. The analysis was focused on the relation between the SCF sensitivity and the physical, spatial parameters and processes of a distributed rainfall–runoff model. The methodology is tested for the Biebrza River catchment, Poland for which a distributed WetSpa model is setup to simulate two years of daily runoff. The SA uses the Latin-Hypercube One-factor-At-a-Time (LH-OAT algorithm, which uses different response functions for each 4 km × 4 km snow zone. The results show that the spatial patterns of sensitivity can be easily interpreted by co-occurrence of different environmental factors such as: geomorphology, soil texture, land-use, precipitation and temperature. Moreover, the spatial pattern of sensitivity under different response functions is related to different spatial parameters and physical processes. The results clearly show that the LH-OAT algorithm is suitable for the spatial sensitivity analysis approach and that the SCF is spatially sensitive in the WetSpa model.

  10. Energy balance and runoff modelling of glaciers in the Kongsfjord basin in northwestern Svalbard

    Science.gov (United States)

    Kohler, J.; Pramanik, A.; van Pelt, W.

    2016-12-01

    Glaciers and ice caps cover 36,000 Km2 or 60% of the land area of the Svalbard archipelago. Roughly 60% of the glaciated area drains to the ocean through tidewater glacier fronts. Runoff from tidewater glaciers is posited to have a significant impact on fjord circulation and thereby on fjord ecosystems. Ocean circulation modelling underway in the Kongsfjord system requires specification of the freshwater amounts contributed by both tidewater and land-terminating glaciers in its basin. The total basin area of Kongsfjord is 1850 km2. We use a coupled surface energy-balance and firn model (Van Pelt et al. 2015) to calculate mass balance and runoff from the Kongsfjord glaciers for the period 1969-2015. Meteorological data from the nearby station at Ny-Ålesund is used for climate forcing in the model domain, with mass balance data at four glaciers in the Kongsfjord watershed used to calibrate model parameters. Precipitation and temperature lapse rates are adjusted on the study glaciers through repeated model runs at mass balance stake locations to match observed and modelled surface mass balance. Long-term discharge measurement at two sites in this region are used to validate the modelled runoff. Spatial and temporal evolution of melt, refreezing and runoff are analyzed, along with the vertical evolution of subsurface conditions. Reference: Van Pelt, W.J.J. & J. Kohler. 2015. Modelling the long-term mass balance and firn evolution of glaciers around Kongsfjorden, Svalbard. J. Glaciol, 61(228), 731-744. Glaciers and ice caps cover 36,000 Km2 or 60% of the land area of the Svalbard archipelago. Roughly 60% of the glaciated area drains to the ocean through tidewater glacier fronts. Runoff from tidewater glaciers is posited to have a significant impact on fjord circulation and thereby on fjord ecosystems. Ocean circulation modelling underway in the Kongsfjord system requires specification of the freshwater amounts contributed by both tidewater and land-terminating glaciers

  11. Evaluating the impact of lower resolutions of digital elevation model on rainfall-runoff modeling for ungauged catchments.

    Science.gov (United States)

    Ghumman, Abul Razzaq; Al-Salamah, Ibrahim Saleh; AlSaleem, Saleem Saleh; Haider, Husnain

    2017-02-01

    Geomorphological instantaneous unit hydrograph (GIUH) usually uses geomorphologic parameters of catchment estimated from digital elevation model (DEM) for rainfall-runoff modeling of ungauged watersheds with limited data. Higher resolutions (e.g., 5 or 10 m) of DEM play an important role in the accuracy of rainfall-runoff models; however, such resolutions are expansive to obtain and require much greater efforts and time for preparation of inputs. In this research, a modeling framework is developed to evaluate the impact of lower resolutions (i.e., 30 and 90 m) of DEM on the accuracy of Clark GIUH model. Observed rainfall-runoff data of a 202-km(2) catchment in a semiarid region was used to develop direct runoff hydrographs for nine rainfall events. Geographical information system was used to process both the DEMs. Model accuracy and errors were estimated by comparing the model results with the observed data. The study found (i) high model efficiencies greater than 90% for both the resolutions, and (ii) that the efficiency of Clark GIUH model does not significantly increase by enhancing the resolution of the DEM from 90 to 30 m. Thus, it is feasible to use lower resolutions (i.e., 90 m) of DEM in the estimation of peak runoff in ungauged catchments with relatively less efforts. Through sensitivity analysis (Monte Carlo simulations), the kinematic wave parameter and stream length ratio are found to be the most significant parameters in velocity and peak flow estimations, respectively; thus, they need to be carefully estimated for calculation of direct runoff in ungauged watersheds using Clark GIUH model.

  12. Applicability of open rainfall data to event-scale urban rainfall-runoff modelling

    Science.gov (United States)

    Niemi, Tero J.; Warsta, Lassi; Taka, Maija; Hickman, Brandon; Pulkkinen, Seppo; Krebs, Gerald; Moisseev, Dmitri N.; Koivusalo, Harri; Kokkonen, Teemu

    2017-04-01

    Rainfall-runoff simulations in urban environments require meteorological input data with high temporal and spatial resolutions. The availability of precipitation data is constantly increasing due to the shift towards more open data sharing. However, the applicability of such data for urban runoff assessments is often unknown. Here, the feasibility of Finnish Meteorological Institute's open rain gauge and open weather radar data as input sources was studied by conducting Storm Water Management Model simulations at a very small (33.5 ha) urban catchment in Helsinki, Finland. In addition to the open data sources, data were also available from two research gauges, one of them located on-site, and from a research radar. The results confirmed the importance of local precipitation measurements for urban rainfall-runoff simulations, implying the suitability of open gauge data to be largely dictated by the gauge's distance from the catchment. Performance of open radar data with 5 min and 1 km2 resolution was acceptable in terms of runoff reproduction, albeit peak flows were constantly and flow volumes often underestimated. Gauge adjustment and advection interpolation were found to improve the quality of the radar data, and at least gauge adjustment should be performed when open radar data are used. Finally, utilizing dual-polarization capabilities of radars has a potential to improve rainfall estimates for high intensity storms although more research is still needed.

  13. Investigating and predicting landslides using a rainfall-runoff model in Southern Norway

    OpenAIRE

    Kråbøl, Eline Haga

    2016-01-01

    Landslides are amongst the most destructive natural hazards, causing damage to infrastructures, such as roads, railways and houses, and can, in a worst-case scenario, take lives. By studying the effect and response of rainfall using the temporal and spatial distribution of the storage and discharge, a better understanding of landslide processes and a more detailed prediction can be possible. This study employs a parameter-parsimonious rainfall-runoff model, the Distance Distribution model (DD...

  14. Users guide for distributed routing rainfall-runoff model

    Science.gov (United States)

    Dawdy, D.R.; Schaake, John C.; Alley, William M.

    1978-01-01

    A computer program of a watershed model for routing urban flood discharges through a branched system of pipes or natural channels using rainfall as input has been developed and documented. The model combines soil-moisture-accounting and rainfall-excess components developed by Dawdy and others (1972) with the kinematic-wave routing method presented by Leclerc and Schaake (1973). (Woodard-USGS)

  15. Dynamic modelling of processes in rivers affected by precipitation runoff

    DEFF Research Database (Denmark)

    Jacobsen, Judith L.

    1997-01-01

    In this thesis, models for the dynamics of oxygen and organic matter in receiving waters (such as rivers and creeks), which are affected by rain, are developed. A time series analysis framework is used, but presented with special emphasis on continuous time state space models. Also, the concept...

  16. Retrospective Analysis of Recent Flood Events With Persistent High Surface Runoff From Hydrological Modelling

    Science.gov (United States)

    Joshi, S.; Hakeem, K. Abdul; Raju, P. V.; Rao, V. V.; Yadav, A.; Diwakar, P. G.; Dadhwal, V. K.

    2014-11-01

    Floods are one of the most common and widespread disasters in India, with an estimated 40Mha of land prone to this natural disaster (National Flood Commission, India). Significant loss of property, infrastructure, livestock, public utilities resulting in large economic losses due to floods are recurrent every year in many parts of India. Flood forecasting and early warning is widely recognized and adopted as non-structural measure to lower the damages caused by the flood events. Estimating the rainfall excess that results into excessive river flow is preliminary effort in riverine flood estimation. Flood forecasting models are in general, are event based and do not fully account for successive and persistent excessive surface runoff conditions. Successive high rainfall events result in saturated soil moisture conditions, favourable for high surface runoff conditions. The present study is to explore the usefulness of hydrological model derived surface runoff, running on continuous times-step, to relate to the occurrence of flood inundation due to persistent and successive high surface runoff conditions. Variable Infiltration Capacity (VIC), a macro-scale hydrological model, was used to simulate daily runoff at systematic grid level incorporating daily meteorological data and land cover data. VIC is a physically based, semi-distributed macroscale hydrological model that represents surface and subsurface hydrologic process on spatially distributed grid cell. It explicitly represents sub-grid heterogeneity in land cover classes, taking their phenological changes into account. In this study, the model was setup for entire India using geo-spatial data available from multiple sources (NRSC, NBSS&LUP, NOAA, and IMD) and was calibrated with river discharge data from CWC at selected river basins. Using the grid-wise surface runoff estimates from the model, an algorithm was developed through a set of thresholds of successive high runoff values in order to identify grids

  17. Stormwater Impaired Watersheds

    Data.gov (United States)

    Vermont Center for Geographic Information — Stormwater impaired watersheds occuring on both the Priority Waters (Part D - Completed TMDL) and 303(d) list of waters (Part A - need TMDL) The Vermont State...

  18. Heavy metals, PAHs and toxicity in stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild

    2011-01-01

    Concentrations of 6 different heavy metals and total Polycyclic Aromatic Hydrocarbons (PAH) were determined in stormwater runoff and in the pond water of two Danish wet detention ponds. The pond water samples were analyzed for toxic effects, using the algae Selenastrum capricornutum as a test......, reducing the potential toxicity of the metal. Another catchment (residential) produced stormwater and pond water with moderate concentration of heavy metals. The pond water occasionally showed toxic effects but no correlation between heavy metals and toxicity was identified. PAHs concentrations were...... for both catchments low and no correlations between PAH concentrations in the pond and toxicity were found....

  19. Top-down methodology for rainfall-runoff modelling and evaluation of hydrological extremes

    Science.gov (United States)

    Willems, Patrick

    2014-05-01

    A top-down methodology is presented for implementation and calibration of a lumped conceptual catchment rainfall-runoff model that aims to produce high model performance (depending on the quality and availability of data) in terms of rainfall-runoff discharges for the full range from low to high discharges, including the peak and low flow extremes. The model is to be used to support water engineering applications, which most often deal with high and low flows as well as cumulative runoff volumes. With this application in mind, the paper wants to contribute to the above-mentioned problems and advancements on model evaluation, model-structure selection, the overparameterization problem and the long time the modeller needs to invest or the difficulties one encounters when building and calibrating a lumped conceptual model for a river catchment. The methodology is an empirical and step-wise technique that includes examination of the various model components step by step through a data-based analysis of response characteristics. The approach starts from a generalized lumped conceptual model structure. In this structure, only the general components of a lumped conceptual model, such as the existence of storage and routing elements, and their inter-links, are pre-defined. The detailed specifications on model equations and parameters are supported by advanced time series analysis of the empirical response between the rainfall and evapotranspiration inputs and the river flow output. Subresponses are separated and submodel components and related subsets of parameters are calibrated as independently as possible. At the same time, the model-structure identification process aims to reach parsimonious submodel-structures, and accounts for the serial dependency of runoff values, which typically is higher for low flows than for high flows. It also accounts for the heteroscedasticity and dependency of model residuals when evaluating the model performance. It is shown that this step

  20. Runoff Prediction Using an Aggregation Hydrology Model on Seulimum River Sub Watershed, Aceh Province, Indonesia

    Directory of Open Access Journals (Sweden)

    Susi Chairani

    2014-11-01

    Full Text Available The objective of the present study was to predict the runoff in Seulimeum River sub watershed by utilizing an aggregation hydrology model. The method in this research consisted of field observation, collecting data and map, testing model, and analyzing data. Some parameters were used as the inputs on the model, such as: maximum storage, actual groundwater storage, soil moisture, and the constant of soil moisture k(t. The aggregation hydrology model was tested using 3 (three statistical parameters, such as; determination coefficient (R2, biased percentage (PBIAS, and Nash-Sutcliffe coefficient (ENS. The result showed that the minimum runoff occured in 1998 was 70.22 mm and the maximum runoff occurred in 1987 was 759.12 mm. The model testing showed that the aggregation hydrology model had a good performance in predicting the discharge of Krueng Seulimemum Sub Watershed; the R2, P biased, and ENS resulted 0.92, -5.21%, and 0.90, respectively

  1. Integration of Volterra model with artificial neural networks for rainfall-runoff simulation in forested catchment of northern Iran

    Science.gov (United States)

    Kashani, Mahsa H.; Ghorbani, Mohammad Ali; Dinpashoh, Yagob; Shahmorad, Sedaghat

    2016-09-01

    Rainfall-runoff simulation is an important task in water resources management. In this study, an integrated Volterra model with artificial neural networks (IVANN) was presented to simulate the rainfall-runoff process. The proposed integrated model includes the semi-distributed forms of the Volterra and ANN models which can explore spatial variation in rainfall-runoff process without requiring physical characteristic parameters of the catchments, while taking advantage of the potential of Volterra and ANNs models in nonlinear mapping. The IVANN model was developed using hourly rainfall and runoff data pertaining to thirteen storms to study short-term responses of a forest catchment in northern Iran; and its performance was compared with that of semi-distributed integrated ANN (IANN) model and lumped Volterra model. The Volterra model was applied as a nonlinear model (second-order Volterra (SOV) model) and solved using the ordinary least square (OLS) method. The models performance were evaluated and compared using five performance criteria namely coefficient of efficiency, root mean square error, error of total volume, relative error of peak discharge and error of time for peak to arrive. Results showed that the IVANN model performs well than the other semi-distributed and lumped models to simulate the rainfall-runoff process. Comparing to the integrated models, the lumped SOV model has lower precision to simulate the rainfall-runoff process.

  2. Using Runoff Data to Calibrate the Community Land Model

    Science.gov (United States)

    Ray, J.; Hou, Z.; Huang, M.; Swiler, L.

    2014-12-01

    We present a statistical method for calibrating the Community Land Model (CLM) using streamflow observations collected between 1999 and 2008 at the outlet of two river basins from the Model Parameter Estimation Experiment (MOPEX), Oostanaula River at Resaca GA, and Walnut River at Winfield KS.. The observed streamflow shows variability over a large range of time-scales, none of which significantly dominates the others; consequently, the time-series seems noisy and is difficult to be directly used in model parameter estimation efforts without significant filtering. We perform a multi-resolution wavelet decomposition of the observed streamflow, and use the wavelet power coefficients (WPC) as the tuning data. We construct a mapping (a surrogate model) between WPC and three hydrological parameters of the CLM using a training set of 256 CLM runs. The dependence of WPC on the parameters is complex and cannot be captured using a surrogate unless the parameter combinations yield physically plausible model predictions, i.e., those that are skillful when compared to observations. Retaining only the top quartile of the runs ensures skillfulness, as measured by the RMS error between observations and CLM predictions. This "screening" of the training data yields a region (the "valid" region) in the parameter space where accurate surrogate models can be created. We construct a classifier for the "valid" region, and, in conjunction with the surrogate models for WPC, pose a Bayesian inverse problem for the three hydrological parameters. The inverse problem is solved using an adaptive Markov chain Monte Carlo (MCMC) method to construct a three-dimensional posterior distribution for the hydrological parameters. Posterior predictive tests using the surrogate model reveal that the posterior distribution is more predictive than the nominal values of the parameters, which are used as default values in the current version of CLM. The effectiveness of the inversion is then validated by

  3. Uncertainty in runoff based on Global Climate Model precipitation and temperature data – Part 2: Estimation and uncertainty of annual runoff and reservoir yield

    Directory of Open Access Journals (Sweden)

    M. C. Peel

    2014-05-01

    Full Text Available Two key sources of uncertainty in projections of future runoff for climate change impact assessments are uncertainty between Global Climate Models (GCMs and within a GCM. Within-GCM uncertainty is the variability in GCM output that occurs when running a scenario multiple times but each run has slightly different, but equally plausible, initial conditions. The limited number of runs available for each GCM and scenario combination within the Coupled Model Intercomparison Project phase 3 (CMIP3 and phase 5 (CMIP5 datasets, limits the assessment of within-GCM uncertainty. In this second of two companion papers, the primary aim is to approximate within-GCM uncertainty of monthly precipitation and temperature projections and assess its impact on modelled runoff for climate change impact assessments. A secondary aim is to assess the impact of between-GCM uncertainty on modelled runoff. Here we approximate within-GCM uncertainty by developing non-stationary stochastic replicates of GCM monthly precipitation and temperature data. These replicates are input to an off-line hydrologic model to assess the impact of within-GCM uncertainty on projected annual runoff and reservoir yield. To-date within-GCM uncertainty has received little attention in the hydrologic climate change impact literature and this analysis provides an approximation of the uncertainty in projected runoff, and reservoir yield, due to within- and between-GCM uncertainty of precipitation and temperature projections. In the companion paper, McMahon et al. (2014 sought to reduce between-GCM uncertainty by removing poorly performing GCMs, resulting in a selection of five better performing GCMs from CMIP3 for use in this paper. Here we present within- and between-GCM uncertainty results in mean annual precipitation (MAP, temperature (MAT and runoff (MAR, the standard deviation of annual precipitation (SDP and runoff (SDR and reservoir yield for five CMIP3 GCMs at 17 world-wide catchments

  4. Runoff and sediment yield modeling in a medium-size mediterranean watershed

    Directory of Open Access Journals (Sweden)

    Ossama M.M. Abdelwahab

    2013-09-01

    Full Text Available The AnnAGNPS model was used to estimate runoff, peak discharge and sediment yield at the event scale in the Carapelle watershed, a Mediterranean medium-size watershed (506 km2 located in Apulia, Southern Italy. The model was calibrated and validated using five years of runoff and sediment yield data measured at a monitoring station located at Ordona – Ponte dei Sauri Bridge. A total of 36 events was used to estimate the output of the model during the period 2007-2011, in comparison to the corresponding observations at the watershed outlet. The model performed well in predicting runoff, as was testified by the high values of the coefficients of efficiency and determination during the validation process. The peak flows predictions were satisfactory especially for the high flow events; the prediction capability of sediment yield was good, even if a slight over-estimation was observed. Finally, the model was used to evaluate the effectiveness of different Management practices (MPs on the watershed (converting wheat to forest, using vegetated streams, crop rotation corn/soybean, no tillage. While the maximum reduction in sediment yield was achieved converting wheat to forest, the best compromises between soil conservation and agriculture resulted to be crop rotations.

  5. Indicator bacteria and associated water quality constituents in stormwater and snowmelt from four urban catchments

    Science.gov (United States)

    Galfi, H.; Österlund, H.; Marsalek, J.; Viklander, M.

    2016-08-01

    Four indicator bacteria were measured in association with physico-chemical constituents and selected inorganics during rainfall, baseflow and snowmelt periods in storm sewers of four urban catchments in a northern Swedish city. The variation patterns of coliforms, Escherichia coli, enterococci and Clostridium perfringens concentrations were assessed in manually collected grab samples together with those of phosphorus, nitrogen, solids, and readings of pH, turbidity, water conductivity, temperature and flow rates to examine whether these constituents could serve as potential indicators of bacteria sources. A similar analysis was applied to variation patterns of eight selected inorganics typical for baseflow and stormwater runoff to test the feasibility of using these inorganics to distinguish between natural and anthropogenic sources of inflow into storm sewers. The monitored catchments varied in size, the degree of development, and land use. Catchment and season (i.e., rainy or snowmelt periods) specific variations were investigated for sets of individual stormwater samples by the principal component analysis (PCA) to identify the constituents with variation patterns similar to those of indicator bacteria, and to exclude the constituents with less similarity. In the reduced data set, the similarities were quantified by the clustering correlation analysis. Finally, the positive/negative relationships found between indicator bacteria and the identified associated constituent groups were described by multilinear regressions. In the order of decreasing concentrations, coliforms, E. coli and enterococci were found in the highest mean concentrations during both rainfall and snowmelt generated runoff. Compared to dry weather baseflow, concentrations of these three indicators in stormwater were 10 (snowmelt runoff) to 102 (rain runoff) times higher. C. perfringens mean concentrations were practically constant regardless of the season and catchment. The type and number of

  6. Parameter estimation in stochastic rainfall-runoff models

    DEFF Research Database (Denmark)

    Jonsdottir, Harpa; Madsen, Henrik; Palsson, Olafur Petur

    2006-01-01

    the parameters, including the noise terms. The parameter estimation method is a maximum likelihood method (ML) where the likelihood function is evaluated using a Kalman filter technique. The ML method estimates the parameters in a prediction error settings, i.e. the sum of squared prediction error is minimized....... For a comparison the parameters are also estimated by an output error method, where the sum of squared simulation error is minimized. The former methodology is optimal for short-term prediction whereas the latter is optimal for simulations. Hence, depending on the purpose it is possible to select whether...... the parameter values are optimal for simulation or prediction. The data originates from Iceland and the model is designed for Icelandic conditions, including a snow routine for mountainous areas. The model demands only two input data series, precipitation and temperature and one output data series...

  7. Runoff Modeling for a Watershed in Pothowar Region of Pakistan

    Directory of Open Access Journals (Sweden)

    Qazi Tallat Mahmood Siddiqui

    2012-07-01

    Full Text Available Floods are among the most devastating natural hazards in the world. Pakistan has big rivers and flood planning and management is mainly concentrated on riverine floods occurring during monsoon. However, flash floods in hilly and Pothowar (semi-hilly area are also common with demonstrated damage potential. This study was taken up to thoroughly investigate flood mechanism and inundation behavior in a watershed in Pothowar region by use of computer modeling with the Lai Stream as a case study. The Lai Stream Basin with an area of 235 km2 is located in northern part of Pakistan. Lai is the main stream passing through Rawalpindi city with a flood damaging history of almost once in every three years. 2001-Flood has been the largest among recorded events claiming 74 human lives, affecting 400,000 people and inflicting a capital loss of USD 0.25 billion. Thorough data analysis was performed to select most suitable data for computer modeling. The whole basin was divided in to fifteen (15 sub-basins and their respective yields were generated and subsequently incorporated in to river network of Lai Stream. Calibration was achieved successfully along the river profile with 2001 flood as target followed by the estimation of standard flood discharge for Lai stream. Thereupon useful recommendations have been made to utilize the model for mitigating flash flood events in urban/inhabited Pothowar (semi-hilly region of Pakistan in particular and world over in general.

  8. A model for assessing effects of climate change on runoff in China

    Institute of Scientific and Technical Information of China (English)

    SU Fengge; XIE Zhenghui

    2003-01-01

    A model is established for assessing the effects of climate change on runoff in China based on the land surface parameterization scheme variable infiltration capacity (VIC). The entire area of China is represented by 2604 cells with a resolution of 60 km×60 km for each cell. Forcing data, soil and vegetation parameters needed by the VIC model for the entire area of China are prepared. Daily forcing data, which are obtained from 740 stations between 1980 and 1990, are interpolated to the 60 km×60 km grid system. The VIC model is run on every grid cell over the whole China, and a routing scheme is run offline with daily input of surface runoff and drainage from the VIC to get hydrograph at basin outlets. The spatial patterns of simulated runoff and mean annual precipitation are consistent very well. The results of monthly streamflow simulations over the Huaihe and Weihe River basins indicate that there is a good agreement between the observed and simulated values, and also initially indicate the rationality and feasibility of the evaluation model.

  9. Event-based rainfall-runoff modelling of the Kelantan River Basin

    Science.gov (United States)

    Basarudin, Z.; Adnan, N. A.; Latif, A. R. A.; Tahir, W.; Syafiqah, N.

    2014-02-01

    Flood is one of the most common natural disasters in Malaysia. According to hydrologists there are many causes that contribute to flood events. The two most dominant factors are the meteorology factor (i.e climate change) and change in land use. These two factors contributed to floods in recent decade especially in the monsoonal catchment such as Malaysia. This paper intends to quantify the influence of rainfall during extreme rainfall events on the hydrological model in the Kelantan River catchment. Therefore, two dynamic inputs were used in the study: rainfall and river discharge. The extreme flood events in 2008 and 2004 were compared based on rainfall data for both years. The events were modeled via a semi-distributed HEC-HMS hydrological model. Land use change was not incorporated in the study because the study only tries to quantify rainfall changes during these two events to simulate the discharge and runoff value. Therefore, the land use data representing the year 2004 were used as inputs in the 2008 runoff model. The study managed to demonstrate that rainfall change has a significant impact to determine the peak discharge and runoff depth for the study area.

  10. Multiple linear regression models of urban runoff pollutant load and event mean concentration considering rainfall variables.

    Science.gov (United States)

    Maniquiz, Marla C; Lee, Soyoung; Kim, Lee-Hyung

    2010-01-01

    Rainfall is an important factor in estimating the event mean concentration (EMC) which is used to quantify the washed-off pollutant concentrations from non-point sources (NPSs). Pollutant loads could also be calculated using rainfall, catchment area and runoff coefficient. In this study, runoff quantity and quality data gathered from a 28-month monitoring conducted on the road and parking lot sites in Korea were evaluated using multiple linear regression (MLR) to develop equations for estimating pollutant loads and EMCs as a function of rainfall variables. The results revealed that total event rainfall and average rainfall intensity are possible predictors of pollutant loads. Overall, the models are indicators of the high uncertainties of NPSs; perhaps estimation of EMCs and loads could be accurately obtained by means of water quality sampling or a long-term monitoring is needed to gather more data that can be used for the development of estimation models.

  11. Monitoring of priority pollutants in dynamic stormwater discharges from urban areas

    DEFF Research Database (Denmark)

    Birch, Heidi

    discharges. Sorption of pollutants to particulate matter and dissolved organic carbon is important for both the toxicity of the pollutants and for removal in stormwater treatment systems. Furthermore sorption is important for sampling using the most common types of passive samplers, which are based on uptake...... campaigns. Therefore this PhD project aimed at improving monitoring programs for priority pollutants in stormwater runoff. By comparing results from a literature study and a screening campaign to the EQSs, it was found that heavy metals (especially Cu and Zn), polyaromatic hydrocarbons (PAHs), Di(2......-ethylhexyl)-phthalate (DEHP) and pesticides were the main pollutants of general concern in stormwater runoff and of concern at the studied catchment (glyphosate was found to be the most relevant pesticide in a Copenhagen setting). These priority pollutants are therefore relevant to monitor in stormwater...

  12. Impacts of Noah model physics on catchment-scale runoff simulations

    Science.gov (United States)

    Zheng, Donghai; Van der Velde, Rogier; Su, Zhongbo; Wen, Jun; Wang, Xin; Booij, Martijn J.; Hoekstra, Arjen Y.; Lv, Shihua; Zhang, Yu; Ek, Michael B.

    2016-01-01

    Noah model physics options validated for the source region of the Yellow River (SRYR) are applied to investigate their ability in reproducing runoff at the catchment scale. Three sets of augmentations are implemented affecting descriptions of (i) turbulent and soil heat transport (Noah-H), (ii) soil water flow (Noah-W), and (iii) frozen ground processes (Noah-F). Five numerical experiments are designed with the three augmented versions, a control run with default model physics and a run with all augmentations (Noah-A). Each experiment is set up with vegetation and soil parameters from Weather Research and Forecasting data set, soil organic matter content from China Soil Database, 0.1° atmospheric forcing data from Institute of Tibetan Plateau Research (Chinese Academy of Sciences), and initial equilibrium model states achieved using a single-year recurrent spin-up. In situ heat flux, soil temperature (Ts), and soil moisture (θ) profile measurements are available for point-scale assessment, whereas monthly streamflow is utilized for the catchment-scale evaluation. The comparison with point measurements shows that the augmentations invoked with Noah-H resolve issues with the heat flux and Ts simulation and Noah-W mitigates deficiencies in the θ simulation, while Noah-A yields improvements for both simulated surface energy and water budgets. In contrast, Noah-F has a minor effect. Also, at catchment scale, the best model performance is found for Noah-A leading to a base flow-dominated runoff regime, whereby the surface runoff contribution remains significant. This study highlights the need for a complete description of vertical heat and water exchanges to correctly simulate the runoff in the seasonally frozen and high-altitude SRYR at the catchment scale.

  13. Robust Initial Wetness Condition Framework of an Event-Based Rainfall–Runoff Model Using Remotely Sensed Soil Moisture

    Directory of Open Access Journals (Sweden)

    Wooyeon Sunwoo

    2017-01-01

    Full Text Available Runoff prediction in limited-data areas is vital for hydrological applications, such as the design of infrastructure and flood defenses, runoff forecasting, and water management. Rainfall–runoff models may be useful for simulation of runoff generation, particularly event-based models, which offer a practical modeling scheme because of their simplicity. However, there is a need to reduce the uncertainties related to the estimation of the initial wetness condition (IWC prior to a rainfall event. Soil moisture is one of the most important variables in rainfall–runoff modeling, and remotely sensed soil moisture is recognized as an effective way to improve the accuracy of runoff prediction. In this study, the IWC was evaluated based on remotely sensed soil moisture by using the Soil Conservation Service-Curve Number (SCS-CN method, which is one of the representative event-based models used for reducing the uncertainty of runoff prediction. Four proxy variables for the IWC were determined from the measurements of total rainfall depth (API5, ground-based soil moisture (SSMinsitu, remotely sensed surface soil moisture (SSM, and soil water index (SWI provided by the advanced scatterometer (ASCAT. To obtain a robust IWC framework, this study consists of two main parts: the validation of remotely sensed soil moisture, and the evaluation of runoff prediction using four proxy variables with a set of rainfall–runoff events in the East Asian monsoon region. The results showed an acceptable agreement between remotely sensed soil moisture (SSM and SWI and ground based soil moisture data (SSMinsitu. In the proxy variable analysis, the SWI indicated the optimal value among the proposed proxy variables. In the runoff prediction analysis considering various infiltration conditions, the SSM and SWI proxy variables significantly reduced the runoff prediction error as compared with API5 by 60% and 66%, respectively. Moreover, the proposed IWC framework with

  14. A simple rainfall-runoff model for the single and long term hydrological performance of green roofs

    DEFF Research Database (Denmark)

    Locatelli, Luca; Mark, Ole; Mikkelsen, Peter Steen

    Green roofs are being widely implemented for storm water control and runoff reduction. There is need for incorporating green roofs into urban drainage models in order to evaluate their impact. These models must have low computational costs and fine time resolution. This paper aims to develop...... a model of green roof hydrological performance. A simple conceptual model for the long term and single event hydrological performance of green roofs, shows to be capable of reproducing observed runoff measurements. The model has surface and subsurface storage components representing the overall retention...... capacity of the green roof. The runoff from the system is described by the non-linear reservoir method and the storage capacity of the green roof is continuously re-established by evapotranspiration. Runoff data from a green roof in Denmark are collected and used for parameter calibration....

  15. Assessing the benefit of snow data assimilation for runoff modeling in Alpine catchments

    Science.gov (United States)

    Griessinger, Nena; Seibert, Jan; Magnusson, Jan; Jonas, Tobias

    2016-09-01

    In Alpine catchments, snowmelt is often a major contribution to runoff. Therefore, modeling snow processes is important when concerned with flood or drought forecasting, reservoir operation and inland waterway management. In this study, we address the question of how sensitive hydrological models are to the representation of snow cover dynamics and whether the performance of a hydrological model can be enhanced by integrating data from a dedicated external snow monitoring system. As a framework for our tests we have used the hydrological model HBV (Hydrologiska Byråns Vattenbalansavdelning) in the version HBV-light, which has been applied in many hydrological studies and is also in use for operational purposes. While HBV originally follows a temperature-index approach with time-invariant calibrated degree-day factors to represent snowmelt, in this study the HBV model was modified to use snowmelt time series from an external and spatially distributed snow model as model input. The external snow model integrates three-dimensional sequential assimilation of snow monitoring data with a snowmelt model, which is also based on the temperature-index approach but uses a time-variant degree-day factor. The following three variations of this external snow model were applied: (a) the full model with assimilation of observational snow data from a dense monitoring network, (b) the same snow model but with data assimilation switched off and (c) a downgraded version of the same snow model representing snowmelt with a time-invariant degree-day factor. Model runs were conducted for 20 catchments at different elevations within Switzerland for 15 years. Our results show that at low and mid-elevations the performance of the runoff simulations did not vary considerably with the snow model version chosen. At higher elevations, however, best performance in terms of simulated runoff was obtained when using the snowmelt time series from the snow model, which utilized data assimilation

  16. Metal accumulation by plants : evaluation of the use of plants in stormwater treatment

    OpenAIRE

    Fritioff, Åsa

    2005-01-01

    Metal contaminated stormwater, i.e. surface runoff in urban areas, can be treated in percolation systems, ponds, or wetlands to prevent the release of metals into receiving waters. Plants in such systems can, for example, attenuate water flow, bind sediment, and directly accumulate metals. By these actions plants affect metal mobility. This study aimed to examine the accumulation of Zn, Cu, Cd, and Pb in roots and shoots of plant species common in stormwater areas. Furthermore, submersed plan...

  17. Multi-Site Calibration of Linear Reservoir Based Geomorphologic Rainfall-Runoff Models

    Directory of Open Access Journals (Sweden)

    Bahram Saeidifarzad

    2014-09-01

    Full Text Available Multi-site optimization of two adapted event-based geomorphologic rainfall-runoff models was presented using Non-dominated Sorting Genetic Algorithm (NSGA-II method for the South Fork Eel River watershed, California. The first model was developed based on Unequal Cascade of Reservoirs (UECR and the second model was presented as a modified version of Geomorphological Unit Hydrograph based on Nash’s model (GUHN. Two calibration strategies were considered as semi-lumped and semi-distributed for imposing (or unimposing the geomorphology relations in the models. The results of models were compared with Nash’s model. Obtained results using the observed data of two stations in the multi-site optimization framework showed reasonable efficiency values in both the calibration and the verification steps. The outcomes also showed that semi-distributed calibration of the modified GUHN model slightly outperformed other models in both upstream and downstream stations during calibration. Both calibration strategies for the developed UECR model during the verification phase showed slightly better performance in the downstream station, but in the upstream station, the modified GUHN model in the semi-lumped strategy slightly outperformed the other models. The semi-lumped calibration strategy could lead to logical lag time parameters related to the basin geomorphology and may be more suitable for data-based statistical analyses of the rainfall-runoff process.

  18. Future Changes in Surface Runoff over Korea Projected by a Regional Climate Model under A1B Scenario

    Directory of Open Access Journals (Sweden)

    Ji-Woo Lee

    2014-01-01

    Full Text Available This study assesses future change of surface runoff due to climate change over Korea using a regional climate model (RCM, namely, the Global/Regional Integrated Model System (GRIMs, Regional Model Program (RMP. The RMP is forced by future climate scenario, namely, A1B of Intergovernmental Panel on Climate Change (IPCC Fourth Assessment Report (AR4. The RMP satisfactorily reproduces the observed seasonal mean and variation of surface runoff for the current climate simulation. The distribution of monsoonal precipitation-related runoff is adequately captured by the RMP. In the future (2040–2070 simulation, it is shown that the increasing trend of temperature has significant impacts on the intra-annual runoff variation. The variability of runoff is increased in summer; moreover, the strengthened possibility of extreme occurrence is detected in the future climate. This study indicates that future climate projection, including surface runoff and its variability over Korea, can be adequately addressed on the RMP testbed. Furthermore, this study reflects that global warming affects local hydrological cycle by changing major water budget components. This study adduces that the importance of runoff should not be overlooked in regional climate studies, and more elaborate presentation of fresh-water cycle is needed to close hydrological circulation in RCMs.

  19. Modelling runoff on ceramic tile roofs using the kinematic wave equations

    Science.gov (United States)

    Silveira, Alexandre; Abrantes, João; de Lima, João; Lira, Lincoln

    2016-04-01

    Rainwater harvesting is a water saving alternative strategy that presents many advantages and can provide solutions to address major water resources problems, such as fresh water scarcity, urban stream degradation and flooding. In recent years, these problems have become global challenges, due to climatic change, population growth and increasing urbanisation. Generally, roofs are the first to come into contact with rainwater; thus, they are the best candidates for rainwater harvesting. In this context, the correct evaluation of roof runoff quantity and quality is essential to effectively design rainwater harvesting systems. Despite this, many studies usually focus on the qualitative aspects in detriment of the quantitative aspects. Laboratory studies using rainfall simulators have been widely used to investigate rainfall-runoff processes. These studies enabled a detailed exploration and systematic replication of a large range of hydrologic conditions, such as rainfall spatial and temporal characteristics, providing for a fast way to obtain precise and consistent data that can be used to calibrate and validate numerical models. This study aims to evaluate the performance of a kinematic wave based numerical model in simulating runoff on sloping roofs, by comparing the numerical results with the ones obtained from laboratory rainfall simulations on a real-scale ceramic tile roof (Lusa tiles). For all studied slopes, simulated discharge hydrographs had a good adjust to observed ones. Coefficient of determination and Nash-Sutcliffe efficiency values were close to 1.0. Particularly, peak discharges, times to peak and peak durations were very well simulated.

  20. Heavy metals, PAHs and toxicity in stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild

    2011-01-01

    Concentrations of 6 different heavy metals and total Polycyclic Aromatic Hydrocarbons (PAH) were determined in stormwater runoff and in the pond water of two Danish wet detention ponds. The pond water samples were analyzed for toxic effects, using the algae Selenastrum capricornutum as a test...... organism. Stormwater and pond water from a catchment with light industry showed high levels of heavy metals, especially zinc and copper. The pond water showed high toxic effects and copper were found to be the main toxicant. Additionally, a large part of the copper was suspected to be complex bound......, reducing the potential toxicity of the metal. Another catchment (residential) produced stormwater and pond water with moderate concentration of heavy metals. The pond water occasionally showed toxic effects but no correlation between heavy metals and toxicity was identified. PAHs concentrations were...

  1. Artful rainwater design creative ways to manage stormwater

    CERN Document Server

    Echols, Stuart

    2015-01-01

    This beautifully illustrated, comprehensive guide explains how to design creative, yet practical, landscapes that treat on-site stormwater management as an opportunity to enhance site design. Stormwater management as art? Absolutely. Rain is a resource that should be valued and celebrated, not merely treated as an urban design problem—and yet, traditional stormwater treatment methods often range from ugly to forgettable. This book shows that it’s possible to effectively manage runoff while also creating inviting, attractive landscapes. It is a must-have resource for landscape architects, urban designers, civil engineers, and architects looking to create landscapes that celebrate rain for the life-giving resource it is-- and contribute to more sustainable, healthy, and even fun, built environments.

  2. Runoff-generated debris flows: observations and modeling of surge initiation, magnitude, and frequency

    Science.gov (United States)

    Kean, Jason W.; McCoy, Scott W.; Tucker, Gregory E.; Staley, Dennis M.; Coe, Jeffrey A.

    2013-01-01

    Runoff during intense rainstorms plays a major role in generating debris flows in many alpine areas and burned steeplands. Yet compared to debris flow initiation from shallow landslides, the mechanics by which runoff generates a debris flow are less understood. To better understand debris flow initiation by surface water runoff, we monitored flow stage and rainfall associated with debris flows in the headwaters of two small catchments: a bedrock-dominated alpine basin in central Colorado (0.06 km2) and a recently burned area in southern California (0.01 km2). We also obtained video footage of debris flow initiation and flow dynamics from three cameras at the Colorado site. Stage observations at both sites display distinct patterns in debris flow surge characteristics relative to rainfall intensity (I). We observe small, quasiperiodic surges at low I; large, quasiperiodic surges at intermediate I; and a single large surge followed by small-amplitude fluctuations about a more steady high flow at high I. Video observations of surge formation lead us to the hypothesis that these flow patterns are controlled by upstream variations in channel slope, in which low-gradient sections act as “sediment capacitors,” temporarily storing incoming bed load transported by water flow and periodically releasing the accumulated sediment as a debris flow surge. To explore this hypothesis, we develop a simple one-dimensional morphodynamic model of a sediment capacitor that consists of a system of coupled equations for water flow, bed load transport, slope stability, and mass flow. This model reproduces the essential patterns in surge magnitude and frequency with rainfall intensity observed at the two field sites and provides a new framework for predicting the runoff threshold for debris flow initiation in a burned or alpine setting.

  3. Runoff of small rocky headwater catchments: Field observations and hydrological modeling

    Science.gov (United States)

    Gregoretti, C.; Degetto, M.; Bernard, M.; Crucil, G.; Pimazzoni, A.; De Vido, G.; Berti, M.; Simoni, A.; Lanzoni, S.

    2016-10-01

    In dolomitic headwater catchments, intense rainstorms of short duration produce runoff discharges that often trigger debris flows on the scree slopes at the base of rock cliffs. In order to measure these discharges, we placed a measuring facility at the outlet (elevation 1770 m a.s.l.) of a small, rocky headwater catchment (area ˜0.032 km2, average slope ˜320%) located in the Venetian Dolomites (North Eastern Italian Alps). The facility consists of an approximately rectangular basin, ending with a sharp-crested weir. Six runoff events were recorded in the period 2011-2014, providing a unique opportunity for characterizing the hydrological response of the catchment. The measured hydrographs display impulsive shapes, with an abrupt raise up to the peak, followed by a rapidly decreasing tail, until a nearly constant plateau is eventually reached. This behavior can be simulated by means of a distributed hydrological model if the excess rainfall is determined accurately. We show that using the Soil Conservation Service Curve-Number (SCS-CN) method and assuming a constant routing velocity invariably results in an underestimated peak flow and a delayed peak time. A satisfactory prediction of the impulsive hydrograph shape, including peak value and timing, is obtained only by combining the SCS-CN procedure with a simplified version of the Horton equation, and simulating runoff routing along the channel network through a matched diffusivity kinematic wave model. The robustness of the proposed methodology is tested through a comparison between simulated and observed timings of runoff or debris flow occurrence in two neighboring alpine basins.

  4. Diagnostic evaluation of distributed physically based model at the REW scale (THREW) using rainfall-runoff event analysis

    Science.gov (United States)

    Tian, F.; Sivapalan, M.; Li, H.; Hu, H.

    2007-12-01

    The importance of diagnostic analysis of hydrological models is increasingly recognized by the scientific community (M. Sivapalan, et al., 2003; H. V. Gupta, et al., 2007). Model diagnosis refers to model structures and parameters being identified not only by statistical comparison of system state variables and outputs but also by process understanding in a specific watershed. Process understanding can be gained by the analysis of observational data and model results at the specific watershed as well as through regionalization. Although remote sensing technology can provide valuable data about the inputs, state variables, and outputs of the hydrological system, observational rainfall-runoff data still constitute the most accurate, reliable, direct, and thus a basic component of hydrology related database. One critical question in model diagnostic analysis is, therefore, what signature characteristic can we extract from rainfall and runoff data. To this date only a few studies have focused on this question, such as Merz et al. (2006) and Lana-Renault et al. (2007), still none of these studies related event analysis with model diagnosis in an explicit, rigorous, and systematic manner. Our work focuses on the identification of the dominant runoff generation mechanisms from event analysis of rainfall-runoff data, including correlation analysis and analysis of timing pattern. The correlation analysis involves the identification of the complex relationship among rainfall depth, intensity, runoff coefficient, and antecedent conditions, and the timing pattern analysis aims to identify the clustering pattern of runoff events in relation to the patterns of rainfall events. Our diagnostic analysis illustrates the changing pattern of runoff generation mechanisms in the DMIP2 test watersheds located in Oklahoma region, which is also well recognized by numerical simulations based on TsingHua Representative Elementary Watershed (THREW) model. The result suggests the usefulness of

  5. Forecasting river discharge using coupled WRF-NMM meteorological model and HBV runoff model, case studies

    Science.gov (United States)

    Dekić, L.; Mihalović, A.; Jovičić, I.; Vladiković, D.; Jerinić, J.; Ivković, M.

    2012-04-01

    This paper examines two episodes of heavy rainfall and significantly increased water levels. The first case relates to the period including the beginning and the end of the third decade of June 2010 at the Kolubara river basin, where extreme rainfall led to two big flood waves on the Kolubara river, whereat water levels exceeded both regular and extraordinary flood defence and approached their historical maximum. The second case relates to the period including the end of November and the beginning of December 2010 at the Jadar river basin, where heavier precipitation caused the water levels of the basin to reach and surpass the occurrence limit (warning level). The HBV (Hydrological Bureau Waterbalance-section) rainfall/snowmelt - runoff model installed at the RHMSS uses gridded quantitative precipitation and air temperature forecast for 72 hours in advance based on meteorological weather forecast WRF-NMM mesoscale model. Nonhydrostatic Mesoscale Model (NMM) core of the Weather Research and Forecasting (WRF) system is flexible state-of-the-art numerical weather prediction model capable to describe and estimate powerful nonhydrostatic mechanism in convective clouds that cause heavy rain. The HBV model is a semi-distributed conceptual catchment model in which the spatial structure of a catchment area is not explicitly modelled. Instead, the sub-basin represents a primary modelling unit while the basin is characterised by area-elevation distribution and classification of vegetation cover and land use distributed by height zone. WRF-NMM forecast shows very good agreement with observations in terms of timing, location and amount of precipitation. They are used as input for HBV model, forecasted discharges at the output profile of the selected river basin represent model output for consideration. 1 Republic Hydrometeorological Service of Serbia

  6. Evaluating the robustness of conceptual rainfall-runoff models under climate variability in northern Tunisia

    Science.gov (United States)

    Dakhlaoui, H.; Ruelland, D.; Tramblay, Y.; Bargaoui, Z.

    2017-07-01

    To evaluate the impact of climate change on water resources at the catchment scale, not only future projections of climate are necessary but also robust rainfall-runoff models that must be fairly reliable under changing climate conditions. The aim of this study was thus to assess the robustness of three conceptual rainfall-runoff models (GR4j, HBV and IHACRES) on five basins in northern Tunisia under long-term climate variability, in the light of available future climate scenarios for this region. The robustness of the models was evaluated using a differential split sample test based on a climate classification of the observation period that simultaneously accounted for precipitation and temperature conditions. The study catchments include the main hydrographical basins in northern Tunisia, which produce most of the surface water resources in the country. A 30-year period (1970-2000) was used to capture a wide range of hydro-climatic conditions. The calibration was based on the Kling-Gupta Efficiency (KGE) criterion, while model transferability was evaluated based on the Nash-Sutcliffe efficiency criterion and volume error. The three hydrological models were shown to behave similarly under climate variability. The models simulated the runoff pattern better when transferred to wetter and colder conditions than to drier and warmer ones. It was shown that their robustness became unacceptable when climate conditions involved a decrease of more than 25% in annual precipitation and an increase of more than +1.75 °C in annual mean temperatures. The reduction in model robustness may be partly due to the climate dependence of some parameters. When compared to precipitation and temperature projections in the region, the limits of transferability obtained in this study are generally respected for short and middle term. For long term projections under the most pessimistic emission gas scenarios, the limits of transferability are generally not respected, which may hamper the

  7. Subgrid Parameterization of the Soil Moisture Storage Capacity for a Distributed Rainfall-Runoff Model

    Directory of Open Access Journals (Sweden)

    Weijian Guo

    2015-05-01

    Full Text Available Spatial variability plays an important role in nonlinear hydrologic processes. Due to the limitation of computational efficiency and data resolution, subgrid variability is usually assumed to be uniform for most grid-based rainfall-runoff models, which leads to the scale-dependence of model performances. In this paper, the scale effect on the Grid-Xinanjiang model was examined. The bias of the estimation of precipitation, runoff, evapotranspiration and soil moisture at the different grid scales, along with the scale-dependence of the effective parameters, highlights the importance of well representing the subgrid variability. This paper presents a subgrid parameterization method to incorporate the subgrid variability of the soil storage capacity, which is a key variable that controls runoff generation and partitioning in the Grid-Xinanjiang model. In light of the similar spatial pattern and physical basis, the soil storage capacity is correlated with the topographic index, whose spatial distribution can more readily be measured. A beta distribution is introduced to represent the spatial distribution of the soil storage capacity within the grid. The results derived from the Yanduhe Basin show that the proposed subgrid parameterization method can effectively correct the watershed soil storage capacity curve. Compared to the original Grid-Xinanjiang model, the model performances are quite consistent at the different grid scales when the subgrid variability is incorporated. This subgrid parameterization method reduces the recalibration necessity when the Digital Elevation Model (DEM resolution is changed. Moreover, it improves the potential for the application of the distributed model in the ungauged basin.

  8. a Empirical Modelation of Runoff in Small Watersheds Using LIDAR Data

    Science.gov (United States)

    Lopatin, J.; Hernández, J.; Galleguillos, M.; Mancilla, G.

    2013-12-01

    Hydrological models allow the simulation of water natural processes and also the quantification and prediction of the effects of human impacts in runoff behavior. However, obtaining the information that is need for applying these models can be costly in both time and resources, especially in large and difficult to access areas. The objective of this research was to integrate LiDAR data in the hydrological modeling of runoff in small watersheds, using derivated hydrologic, vegetation and topography variables. The study area includes 10 small head watersheds cover bay forest, between 2 and 16 ha, which are located in the south-central coastal range of Chile. In each of the former instantaneous rainfall and runoff flow of a total of 15 rainfall events were measured, between August 2012 and July 2013, yielding a total of 79 observations. In March 2011 a Harrier 54/G4 Dual System was used to obtain a LiDAR point cloud of discrete pulse with an average of 4.64 points per square meter. A Digital Terrain Model (DTM) of 1 meter resolution was obtained from the point cloud, and subsequently 55 topographic variables were derived, such as physical watershed parameters and morphometric features. At the same time, 30 vegetation descriptive variables were obtained directly from the point cloud and from a Digital Canopy Model (DCM). The classification and regression "Random Forest" (RF) algorithm was used to select the most important variables in predicting water height (liters), and the "Partial Least Squares Path Modeling" (PLS-PM) algorithm was used to fit a model using the selected set of variables. Four Latent variables were selected (outer model) related to: climate, topography, vegetation and runoff, where in each one was designated a group of the predictor variables selected by RF (inner model). The coefficient of determination (R2) and Goodnes-of-Fit (GoF) of the final model were obtained. The best results were found when modeling using only the upper 50th percentile of

  9. Toxicity characterization of urban stormwater with bioanalytical tools.

    Science.gov (United States)

    Tang, Janet Y M; Aryal, Rupak; Deletic, Ana; Gernjak, Wolfgang; Glenn, Eva; McCarthy, David; Escher, Beate I

    2013-10-01

    Stormwater harvesting has become an attractive alternative strategy to address the rising demand for urban water supply due to limited water sources and population growth. Nevertheless, urban stormwater is also a major source of surface water pollution. Runoff from different urban catchments with source contributions from anthropogenic activities and various land uses causes variable contaminant profiles, thus posing a challenging task for environmental monitoring and risk assessment. A thorough understanding of raw stormwater quality is essential to develop appropriate treatment facilities for potential indirect potable reuse of stormwater. While some of the key chemical components have previously been characterized, only scarce data are available on stormwater toxicity. We benchmarked stormwater samples from urban, residential and industrial sites across various Australian capital cities against samples from the entire water cycle, from sewage to drinking water. Six biological endpoints, targeting groups of chemicals with modes of toxic action of particular relevance for human and environmental health, were investigated: non-specific toxicity (Microtox and combined algae test), the specific modes of action of phytotoxicity (combined algae test), dioxin-like activity (AhR-CAFLUX), and estrogenicity (E-SCREEN), as well as reactive toxicity encompassing genotoxicity (umuC) and oxidative stress (AREc32). Non-specific toxicity was highly variable across sites. The baseline toxicity equivalent concentrations of the most polluted samples were similar to secondary treated effluent from wastewater treatment plants. Phytotoxicity results correlated well with the measured herbicide concentrations at all sites. High estrogenicity was found in two sampling events and could be related to sewage overflow. Genotoxicity, dioxin-like activity, and oxidative stress response were evident in only three of the samples where the stormwater drain was beside a heavy traffic road

  10. Modelling the impact of increasing soil sealing on runoff coefficients at regional scale: a hydropedological approach

    Directory of Open Access Journals (Sweden)

    Ungaro Fabrizio

    2014-03-01

    Full Text Available Soil sealing is the permanent covering of the land surface by buildings, infrastructures or any impermeable artificial material. Beside the loss of fertile soils with a direct impact on food security, soil sealing modifies the hydrological cycle. This can cause an increased flooding risk, due to urban development in potential risk areas and to the increased volumes of runoff. This work estimates the increase of runoff due to sealing following urbanization and land take in the plain of Emilia Romagna (Italy, using the Green and Ampt infiltration model for two rainfall return periods (20 and 200 years in two different years, 1976 and 2008. To this goal a hydropedological approach was adopted in order to characterize soil hydraulic properties via locally calibrated pedotransfer functions (PTF. PTF inputs were estimated via sequential Gaussian simulations coupled with a simple kriging with varying local means, taking into account soil type and dominant land use. Results show that in the study area an average increment of 8.4% in sealed areas due to urbanization and sprawl induces an average increment in surface runoff equal to 3.5 and 2.7% respectively for 20 and 200-years return periods, with a maximum > 20% for highly sealed coast areas.

  11. Comparing bottom-up and top-down parameterisations of a process-based runoff generation model tailored on floods

    Science.gov (United States)

    Antonetti, Manuel; Scherrer, Simon; Margreth, Michael; Zappa, Massimiliano

    2016-04-01

    Information about the spatial distribution of dominant runoff processes (DRPs) can improve flood predictions on ungauged basins, where conceptual rainfall-runoff models usually appear to be limited due to the need for calibration. For example, hydrological classifications based on DRPs can be used as regionalisation tools assuming that, once a model structure and its parameters have been identified for each DRP, they can be transferred to other areas where the same DRP occurs. Here we present a process-based runoff generation model as an event-based spin-off of the conceptual hydrological model PREVAH. The model is grid-based and consists of a specific storage system for each DRP. To unbind the parameter values from catchment-related characteristics, the runoff concentration and the flood routing are uncoupled from the runoff generation routine and simulated separately. For the model parameterisation, two contrasting approaches are applied. First, in a bottom-up approach, the parameters of the runoff generation routine are determined a priori based on the results of sprinkling experiments on 60-100 m2 hillslope plots at several grassland locations in Switzerland. The model is, then, applied on a small catchment (0.5 km2) on the Swiss Plateau, and the parameters linked to the runoff concentration are calibrated on a single heavy rainfall-runoff event. The whole system is finally verified on several nearby catchments of larger sizes (up to 430 km2) affected by different heavy rainfall events. In a second attempt, following a top-down approach, all the parameters are calibrated on the largest catchment under investigation and successively verified on three sub-catchments. Simulation results from both parameterisation techniques are finally compared with results obtained with the traditional PREVAH.

  12. Enabling high-quality observations of surface imperviousness for water runoff modelling from unmanned aerial vehicles

    Science.gov (United States)

    Tokarczyk, Piotr; Leitao, Joao Paulo; Rieckermann, Jörg; Schindler, Konrad; Blumensaat, Frank

    2015-04-01

    Modelling rainfall-runoff in urban areas is increasingly applied to support flood risk assessment particularly against the background of a changing climate and an increasing urbanization. These models typically rely on high-quality data for rainfall and surface characteristics of the area. While recent research in urban drainage has been focusing on providing spatially detailed rainfall data, the technological advances in remote sensing that ease the acquisition of detailed land-use information are less prominently discussed within the community. The relevance of such methods increase as in many parts of the globe, accurate land-use information is generally lacking, because detailed image data is unavailable. Modern unmanned air vehicles (UAVs) allow acquiring high-resolution images on a local level at comparably lower cost, performing on-demand repetitive measurements, and obtaining a degree of detail tailored for the purpose of the study. In this study, we investigate for the first time the possibility to derive high-resolution imperviousness maps for urban areas from UAV imagery and to use this information as input for urban drainage models. To do so, an automatic processing pipeline with a modern classification method is tested and applied in a state-of-the-art urban drainage modelling exercise. In a real-life case study in the area of Lucerne, Switzerland, we compare imperviousness maps generated from a consumer micro-UAV and standard large-format aerial images acquired by the Swiss national mapping agency (swisstopo). After assessing their correctness, we perform an end-to-end comparison, in which they are used as an input for an urban drainage model. Then, we evaluate the influence which different image data sources and their processing methods have on hydrological and hydraulic model performance. We analyze the surface runoff of the 307 individual sub-catchments regarding relevant attributes, such as peak runoff and volume. Finally, we evaluate the model

  13. High-quality observation of surface imperviousness for urban runoff modelling using UAV imagery

    Directory of Open Access Journals (Sweden)

    P. Tokarczyk

    2015-01-01

    Full Text Available Modelling rainfall–runoff in urban areas is increasingly applied to support flood risk assessment particularly against the background of a changing climate and an increasing urbanization. These models typically rely on high-quality data for rainfall and surface characteristics of the area. While recent research in urban drainage has been focusing on providing spatially detailed rainfall data, the technological advances in remote sensing that ease the acquisition of detailed land-use information are less prominently discussed within the community. The relevance of such methods increase as in many parts of the globe, accurate land-use information is generally lacking, because detailed image data is unavailable. Modern unmanned air vehicles (UAVs allow acquiring high-resolution images on a local level at comparably lower cost, performing on-demand repetitive measurements, and obtaining a degree of detail tailored for the purpose of the study. In this study, we investigate for the first time the possibility to derive high-resolution imperviousness maps for urban areas from UAV imagery and to use this information as input for urban drainage models. To do so, an automatic processing pipeline with a modern classification method is tested and applied in a state-of-the-art urban drainage modelling exercise. In a real-life case study in the area of Lucerne, Switzerland, we compare imperviousness maps generated from a consumer micro-UAV and standard large-format aerial images acquired by the Swiss national mapping agency (swisstopo. After assessing their correctness, we perform an end-to-end comparison, in which they are used as an input for an urban drainage model. Then, we evaluate the influence which different image data sources and their processing methods have on hydrological and hydraulic model performance. We analyze the surface runoff of the 307 individual subcatchments regarding relevant attributes, such as peak runoff and volume. Finally, we

  14. Tropical stormwater floods: a sustainable solution

    Science.gov (United States)

    Molinie, Jack; Bade, Francois; Nagau, Jimmy; Nuiro, Paul

    2017-04-01

    Stormwater management is one of the most difficult problem of urban and suburban area. The urban runoff volume related to rain intensity and surfaces properties can lead to flood. Thereby, urban flooding creates considerable infrastructure problem, economics and human damages. In tropical countries, burgeoning human population coupled with unplanned urbanization altered the natural drainage. Consequently, classical intense rain around 100 cm/h produces frequent street flooding. In our case, we study the management of intense tropical rain, by using a network of individual rain storage tanks. The study area is economical and industrial zone installed in a coastal plain , with seventy per cent of impermeable surface (roads, parking lots, building roof, …) and thirty per cent of wetland (mangrove, …). Our solution is to delay the routes and parking lots runoff to the roof one. We propose sustainable individual water storage and a real time dynamical management, which permit to control the roof water arrival in the stormwater culvert. During the remaining time, the stored rainwater can be used for domestic activities instead of the use of drinking water.

  15. High-quality observation of surface imperviousness for urban runoff modelling using UAV imagery

    Science.gov (United States)

    Tokarczyk, P.; Leitao, J. P.; Rieckermann, J.; Schindler, K.; Blumensaat, F.

    2015-10-01

    Modelling rainfall-runoff in urban areas is increasingly applied to support flood risk assessment, particularly against the background of a changing climate and an increasing urbanization. These models typically rely on high-quality data for rainfall and surface characteristics of the catchment area as model input. While recent research in urban drainage has been focusing on providing spatially detailed rainfall data, the technological advances in remote sensing that ease the acquisition of detailed land-use information are less prominently discussed within the community. The relevance of such methods increases as in many parts of the globe, accurate land-use information is generally lacking, because detailed image data are often unavailable. Modern unmanned aerial vehicles (UAVs) allow one to acquire high-resolution images on a local level at comparably lower cost, performing on-demand repetitive measurements and obtaining a degree of detail tailored for the purpose of the study. In this study, we investigate for the first time the possibility of deriving high-resolution imperviousness maps for urban areas from UAV imagery and of using this information as input for urban drainage models. To do so, an automatic processing pipeline with a modern classification method is proposed and evaluated in a state-of-the-art urban drainage modelling exercise. In a real-life case study (Lucerne, Switzerland), we compare imperviousness maps generated using a fixed-wing consumer micro-UAV and standard large-format aerial images acquired by the Swiss national mapping agency (swisstopo). After assessing their overall accuracy, we perform an end-to-end comparison, in which they are used as an input for an urban drainage model. Then, we evaluate the influence which different image data sources and their processing methods have on hydrological and hydraulic model performance. We analyse the surface runoff of the 307 individual subcatchments regarding relevant attributes, such as peak

  16. Procedures for adjusting regional regression models of urban-runoff quality using local data

    Science.gov (United States)

    Hoos, A.B.; Sisolak, J.K.

    1993-01-01

    Statistical operations termed model-adjustment procedures (MAP?s) can be used to incorporate local data into existing regression models to improve the prediction of urban-runoff quality. Each MAP is a form of regression analysis in which the local data base is used as a calibration data set. Regression coefficients are determined from the local data base, and the resulting `adjusted? regression models can then be used to predict storm-runoff quality at unmonitored sites. The response variable in the regression analyses is the observed load or mean concentration of a constituent in storm runoff for a single storm. The set of explanatory variables used in the regression analyses is different for each MAP, but always includes the predicted value of load or mean concentration from a regional regression model. The four MAP?s examined in this study were: single-factor regression against the regional model prediction, P, (termed MAP-lF-P), regression against P,, (termed MAP-R-P), regression against P, and additional local variables (termed MAP-R-P+nV), and a weighted combination of P, and a local-regression prediction (termed MAP-W). The procedures were tested by means of split-sample analysis, using data from three cities included in the Nationwide Urban Runoff Program: Denver, Colorado; Bellevue, Washington; and Knoxville, Tennessee. The MAP that provided the greatest predictive accuracy for the verification data set differed among the three test data bases and among model types (MAP-W for Denver and Knoxville, MAP-lF-P and MAP-R-P for Bellevue load models, and MAP-R-P+nV for Bellevue concentration models) and, in many cases, was not clearly indicated by the values of standard error of estimate for the calibration data set. A scheme to guide MAP selection, based on exploratory data analysis of the calibration data set, is presented and tested. The MAP?s were tested for sensitivity to the size of a calibration data set. As expected, predictive accuracy of all MAP?s for

  17. A simple model for farmland nitrogen loss to surface runoff with raindrop driven process

    Science.gov (United States)

    Tong, J.; Li, J.

    2016-12-01

    It has been widely recognized that surface runoff from the agricultural fields is an important source of non-point source pollution (NPSP). Moreover, as the agricultural country with the largest nitrogen fertilizer production, import and consumption in the world, our nation should pay greater attention to the over-application and inefficient use of nitrogen (N) fertilizer, which may cause severe pollution both in surface water and groundwater. To figure out the transfer mechanism between the soil solution and surface runoff, lots of laboratory test were conducted and related models were established in this study. But little of them was carried out in field scale since a part of variables are hard to control and some uncontrollable natural factors including rainfall intensity, temperature, wind speeds, soil spatial heterogeneity etc., may affect the field experimental results. Despite that, field tests can better reflect the mechanism of soil chemical loss to surface runoff than laboratory experiments, and the latter tend to oversimplify the environmental conditions. Therefore, a physically based, nitrogen transport model was developed and tested with so called semi-field experiments (i.e., artificial rainfall instead of natural rainfall was applied in the test). Our model integrated both raindrop driven process and diffusion effect along with the simplified nitrogen chain reactions. The established model was solved numerically through the modified Hydrus-1d source code, and the model simulations closely agree with the experimental data. Furthermore, our model indicates that the depth of the exchange layer and raindrop induced water transfer rate are two important parameters, and they have different impacts on the simulation results. The study results can provide references for preventing and controlling agricultural NPSP.

  18. Urban Stormwater Infiltration Perspectives

    DEFF Research Database (Denmark)

    Geldof, Govert; Jacobsen, Per; Fujita, Shoichi

    1994-01-01

    water management. This paper focuses on the possibilities for urban stormwater infiltration. The results of three studies are presented. The first study concerns the flooding of the Shirako River in Tokyo. It is shown that with the help of stormwater infiltration the floods can be reduced remarkably......In urban areas there are many problems with water management: combined sewer overflows, peak flows, man-induced droughts, consolidation of the soil, damage from frost penetration, etc. It is preferable to look at all these problems in relation to each other, according the concept of integrated...... shows the impact of urban stormwater infiltration on the groundwater flux in an area in the south of the Netherlands. To relate the different results from the three studies an analogy is introduced with the human body. The combination of problems results in a so-called urban hang-over. It is shown...

  19. On hydrologic similarity: A dimensionless flood frequency model using a generalized geomorphologic unit hydrograph and partial area runoff generation

    Science.gov (United States)

    Sivapalan, Murugesu; Wood, Eric F.; Beven, Keith J.

    1993-01-01

    One of the shortcomings of the original theory of the geomorphologic unit hydrograph (GUH) is that it assumes that runoff is generated uniformly from the entire catchment area. It is now recognized that in many catchments much of the runoff during storm events is produced on partial areas which usually form on narrow bands along the stream network. A storm response model that includes runoff generation on partial areas by both Hortonian and Dunne mechanisms was recently developed by the authors. In this paper a methodology for integrating this partial area runoff generation model with the GUH-based runoff routing model is presented; this leads to a generalized GUH. The generalized GUH and the storm response model are then used to estimate physically based flood frequency distributions. In most previous work the initial moisture state of the catchment had been assumed to be constant for all the storms. In this paper we relax this assumption and allow the initial moisture conditions to vary between storms. The resulting flood frequency distributions are cast in a scaled dimensionless framework where issues such as catchment scale and similarity can be conveniently addressed. A number of experiments are performed to study the sensitivity of the flood frequency response to some of the 'similarity' parameters identified in this formulation. The results indicate that one of the most important components of the derived flood frequency model relates to the specification of processes within the runoff generation model; specifically the inclusion of both saturation excess and Horton infiltration excess runoff production mechanisms. The dominance of these mechanisms over different return periods of the flood frequency distribution can significantly affect the distributional shape and confidence limits about the distribution. Comparisons with observed flood distributions seem to indicate that such mixed runoff production mechanisms influence flood distribution shape. The

  20. Estimation of Model and Parameter Uncertainty For A Distributed Rainfall-runoff Model

    Science.gov (United States)

    Engeland, K.

    The distributed rainfall-runoff model Ecomag is applied as a regional model for nine catchments in the NOPEX area in Sweden. Ecomag calculates streamflow on a daily time resolution. The posterior distribution of the model parameters is conditioned on the observed streamflow in all nine catchments, and calculated using Bayesian statistics. The distribution is estimated by Markov chain Monte Carlo (MCMC). The Bayesian method requires a definition of the likelihood of the parameters. Two alter- native formulations are used. The first formulation is a subjectively chosen objective function describing the goodness of fit between the simulated and observed streamflow as it is used in the GLUE framework. The second formulation is to use a more statis- tically correct likelihood function that describes the simulation errors. The simulation error is defined as the difference between log-transformed observed and simulated streamflows. A statistical model for the simulation errors is constructed. Some param- eters are dependent on the catchment, while others depend on climate. The statistical and the hydrological parameters are estimated simultaneously. Confidence intervals, due to the uncertainty of the Ecomag parameters, for the simulated streamflow are compared for the two likelihood functions. Confidence intervals based on the statis- tical model for the simulation errors are also calculated. The results indicate that the parameter uncertainty depends on the formulation of the likelihood function. The sub- jectively chosen likelihood function gives relatively wide confidence intervals whereas the 'statistical' likelihood function gives more narrow confidence intervals. The statis- tical model for the simulation errors indicates that the structural errors of the model are as least as important as the parameter uncertainty.

  1. Hourly runoff forecasting for flood risk management: Application of various computational intelligence models

    Science.gov (United States)

    Badrzadeh, Honey; Sarukkalige, Ranjan; Jayawardena, A. W.

    2015-10-01

    Reliable river flow forecasts play a key role in flood risk mitigation. Among different approaches of river flow forecasting, data driven approaches have become increasingly popular in recent years due to their minimum information requirements and ability to simulate nonlinear and non-stationary characteristics of hydrological processes. In this study, attempts are made to apply four different types of data driven approaches, namely traditional artificial neural networks (ANN), adaptive neuro-fuzzy inference systems (ANFIS), wavelet neural networks (WNN), and, hybrid ANFIS with multi resolution analysis using wavelets (WNF). Developed models applied for real time flood forecasting at Casino station on Richmond River, Australia which is highly prone to flooding. Hourly rainfall and runoff data were used to drive the models which have been used for forecasting with 1, 6, 12, 24, 36 and 48 h lead-time. The performance of models further improved by adding an upstream river flow data (Wiangaree station), as another effective input. All models perform satisfactorily up to 12 h lead-time. However, the hybrid wavelet-based models significantly outperforming the ANFIS and ANN models in the longer lead-time forecasting. The results confirm the robustness of the proposed structure of the hybrid models for real time runoff forecasting in the study area.

  2. Assessing the Influences of Urbanization On Dissolved Organic Nitrogen in Stormwater and a Receiving Stream

    Science.gov (United States)

    Lusk, M. G.; Toor, G.

    2013-12-01

    Nitrogen (N) is present in several forms in terrestrial and aquatic systems. In water bodies, N is present in inorganic (NH4, NO3) and organic (both dissolved and particulate) forms. Nitrogen carried via stormwater runoff or leaching from fertilized urban landscapes to water bodies can have detrimental effects on water quality because the inorganic N forms are readily available to phytoplankton. There is growing evidence that a part of the dissolved organic N (DON) may also be bioavailable to phytoplankton. DON in urban stormwater runoff, for example, has been shown to be highly bioavailable. The objective of this research is to characterize the sources and chemical fractionation of organic N in stormwater runoff from an urban residential neighborhood and in streamwater along an urban to rural gradient. We hypothesize that urban stormwater DON will be highly fractionated into labile low-molecular weight fractions and that streamwater DON will become increasingly bioavailable with increased urbanization because of shifts in vegetation patterns and hydrologic flowpaths. To test this hypothesis, we are collecting stormwater runoff from an urban neighborhood near Tampa, Florida and streamwater from both urban and rural sub-basins of the adjacent Alafia River.

  3. A characterization of Greenland Ice Sheet surface melt and runoff in contemporary reanalyses and a regional climate model

    Directory of Open Access Journals (Sweden)

    Richard eCullather

    2016-02-01

    Full Text Available For the Greenland Ice Sheet (GrIS, large-scale melt area has increased in recent years and is detectable via remote sensing, but its relation to runoff is not known. Historical, modeled melt area and runoff from Modern-Era Retrospective Analysis for Research and Applications (MERRA-Replay, the Interim Re-Analysis of the European Centre for Medium Range Weather Forecasts (ERA-I, the Climate Forecast System Reanalysis (CFSR, the Modèle Atmosphérique Régional (MAR, and the Arctic System Reanalysis (ASR are examined. These sources compare favorably with satellite-derived estimates of surface melt area for the period 2000-2012. Spatially, the models markedly disagree on the number of melt days in the interior of the southern part of the ice sheet, and on the extent of persistent melt areas in the northeastern GrIS. Temporally, the models agree on the mean seasonality of daily surface melt and on the timing of large-scale melt events in 2012. In contrast, the models disagree on the amount, seasonality, spatial distribution, and temporal variability of runoff. As compared to global reanalyses, time series from MAR indicate a lower correlation between runoff and melt area (r2 = 0.805. Runoff in MAR is much larger in the second half of the melt season for all drainage basins, while the ASR indicates larger runoff in the first half of the year. This difference in seasonality for the MAR and to an extent for the ASR provide a hysteresis in the relation between runoff and melt area, which is not found in the other models. The comparison points to a need for reliable observations of surface runoff.

  4. Bayesian uncertainty assessment of flood predictions in ungauged urban basins for conceptual rainfall-runoff models

    Science.gov (United States)

    Sikorska, A. E.; Scheidegger, A.; Banasik, K.; Rieckermann, J.

    2012-04-01

    Urbanization and the resulting land-use change strongly affect the water cycle and runoff-processes in watersheds. Unfortunately, small urban watersheds, which are most affected by urban sprawl, are mostly ungauged. This makes it intrinsically difficult to assess the consequences of urbanization. Most of all, it is unclear how to reliably assess the predictive uncertainty given the structural deficits of the applied models. In this study, we therefore investigate the uncertainty of flood predictions in ungauged urban basins from structurally uncertain rainfall-runoff models. To this end, we suggest a procedure to explicitly account for input uncertainty and model structure deficits using Bayesian statistics with a continuous-time autoregressive error model. In addition, we propose a concise procedure to derive prior parameter distributions from base data and successfully apply the methodology to an urban catchment in Warsaw, Poland. Based on our results, we are able to demonstrate that the autoregressive error model greatly helps to meet the statistical assumptions and to compute reliable prediction intervals. In our study, we found that predicted peak flows were up to 7 times higher than observations. This was reduced to 5 times with Bayesian updating, using only few discharge measurements. In addition, our analysis suggests that imprecise rainfall information and model structure deficits contribute mostly to the total prediction uncertainty. In the future, flood predictions in ungauged basins will become more important due to ongoing urbanization as well as anthropogenic and climatic changes. Thus, providing reliable measures of uncertainty is crucial to support decision making.

  5. Modelled seasonal forecasts of snow water equivalent and runoff in alpine catchments

    Science.gov (United States)

    Förster, Kristian; Hanzer, Florian; Schöber, Johannes; Huttenlau, Matthias; Achleitner, Stefan; Strasser, Ulrich

    2016-04-01

    Seasonal forecasts of water balance components are becoming increasingly important for hydrological applications. These forecasts are typically derived from coupled atmosphere-ocean climate models, which enable physically based seasonal forecasts. In mountainous regions, however, topography is complex whilst typical spatial resolutions of the climate models are still comparably coarse, i.e in the data, ridges and valleys are not represented with sufficient accuracy. Therefore, seasonal predictions of atmospheric variables require consideration of representative gradients. We present first results of seasonal forecasts and re-forecasts processed by the NCEP (National Centers for Environmental Prediction) Climate Forecast System version 2 (CFSv2). These are prepared for monthly time steps in order to be used for ensemble runs of water balance simulation using the Alpine Water balance And Runoff Estimation model (AWARE). This model has been designed for monthly seasonal predictions in ice- and snowmelt dominated catchments. The study area is the Inn catchment in Tyrol/Austria, including its headwaters in Switzerland. Results are evaluated for both anomalies of meteorological input data (temperature and precipitation), as well as balance components including snow water equivalent and runoff, both simulated with AWARE. Based on model skill evaluations derived from forecasts and observations, the model chain CFSv2 - AWARE proves helpful to analyse possible future hydrological system states of mountainous catchments with emphasis on spatio-temporal snow cover evolution.

  6. Modelling Snowmelt Runoff under Climate Change Scenarios in an Ungauged Mountainous Watershed, Northwest China

    Directory of Open Access Journals (Sweden)

    Yonggang Ma

    2013-01-01

    Full Text Available An integrated modeling system has been developed for analyzing the impact of climate change on snowmelt runoff in Kaidu Watershed, Northwest China. The system couples Hadley Centre Coupled Model version 3 (HadCM3 outputs with Snowmelt Runoff Model (SRM. The SRM was verified against observed discharge for outlet hydrological station of the watershed during the period from April to September in 2001 and generally performed well for Nash-Sutcliffe coefficient (EF and water balance coefficient (RE. The EF is approximately over 0.8, and the water balance error is lower than ± 10%, indicating reasonable prediction accuracy. The Statistical Downscaling Model (SDSM was used to downscale coarse outputs of HadCM3, and then the downscaled future climate data were used as inputs of the SRM. Four scenarios were considered for analyzing the climate change impact on snowmelt flow in the Kaidu Watershed. And the results indicated that watershed hydrology would alter under different climate change scenarios. The stream flow in spring is likely to increase with the increased mean temperature; the discharge and peck flow in summer decrease with the decreased precipitation under Scenarios 1 and 2. Moreover, the consideration of the change in cryosphere area would intensify the variability of stream flow under Scenarios 3 and 4. The modeling results provide useful decision support for water resources management.

  7. Snowmelt and runoff modelling of an Arctic hydrological basin in west Greenland

    Science.gov (United States)

    Bøggild, C. E.; Knudby, C. J.; Knudsen, M. B.; Starzer, W.

    1999-09-01

    This paper compares the performance of a conceptual modelling system and several physically-based models for predicting runoff in a large hydrological basin, Tasersuaq, in west Greenland. This basin, which is typical of many Greenland basins, is interesting because of the fast hydrological response to changing conditions. Due to the predominance of exposed bedrock surface and only minor occurrence of sediments and organic soils, there is little restraint to run-off, making the treatment of the snowmelt component of primary importance.Presently a conceptual modelling system, HBV, is applied in Greenland and also in most of the arctic regions of Scandinavia for operational forecasting. A general wish to use hydrological models for other purposes, such as to improve data collection and to gain insight into the hydrological processes has promoted interest in the more physically-based hydrological models. In this paper, two degree-day models, the Danish version of the physically-based SHE distributed hydrological modelling system (MIKE SHE) and the conceptual HBV model are compared with a new model that links MIKE SHE and a distributed energy balance model developed for this study, APUT.The HBV model performs the best overall simulation of discharge, which presently makes it most suited for general forecasting. The combination of MIKE SHE and APUT i.e. a physically based modelling system shows promising results by improving the timing of the initiation of spring flood, but does not perform as well throughout the remaining part of the snowmelt season. The modelling study shows that local parameters such as the snow depletion curve, the temporal snow albedo and perhaps also melt water storage need to be more precisely determined from field studies before physically-based modelling can be improved.

  8. Modeling Greenland ice sheet present-day and near-future runoff contribution.

    Science.gov (United States)

    Peano, Daniele; Colleoni, Florence; Masina, Simona

    2014-05-01

    The last IPCC report [AR5, IPCC] has shown an increasing contribution from Greenland melting to global sea-level over the last decade, increasing from 0.09 mm/year (period 1992-2001) to 0.59 mm/year (period 2002-2011). Given its strategic location, i.e. close to the main North Atlantic ocean convection sites, it is therefore of importance to better assess ice sheet melting and its impact on regional ocean processes. So far, runoff estimate from ice sheet has been poorly constrained (e.g. [Hanna et al., 2005], [Hanna et al., 2008]) and most of the time the few estimates comes from regional atmospheric models or general circulation models (e.g. [Edwards et al., 2013], [Fettweis et al., 2013]). Here, we present the results from the implementation of a routing scheme into the thermo-mechanical ice sheet-ice shelves model GRISLI [Ritz et al, 2001], applied to the Greenland ice sheet mass evolution over the 20th and 21st centuries. The routing scheme is based on the "multiple flow direction" developed by [Quinn et al., 1991]. We further improved this scheme by considering topographic depressions as possible "lakes" to be filled by meltwater. In this way, when a depression is filled, only the extra water is routed towards the Greenland coasts. This allow us to obtain an estimate of the total amount of freshwater reaching the ocean at each time step of the model integration, as well as a time-varying spatial distribution of the runoff along the coasts of Greenland. This routing scheme is applied in routing both surface and basal meltwater. Surface meltwater is computed by means of a PDD method [Fausto et al., 2007] on which only a fraction is considered for routing while the basal melting rate is part of the heat balance at the ice-bed interface. Runoff is simulated on a 5km x 5km horizontal grid and validation is performed over the 20th century using mean annual total precipitation and air temperature at 2 meters from Era-Interim reanalysis [Dee et al., 2011]. Near future

  9. Monitoring and Modelling Glacier Melt and Runoff on Juncal Norte Glacier, Aconcagua River Basin, Central Chile

    Science.gov (United States)

    Pellicciotti, F.; Helbing, J. F.; Araos, J.; Favier, V.; Rivera, A.; Corripio, J.; Sicart, J. M.

    2006-12-01

    Results from a recent glacio-meteorological experiment on the Juncal Norte glacier, in central Chile, are presented. Melt water is a crucial resource in the Central Andes, as it provides drinking water, water for agriculture and for industrial uses. There is also increasing competition for water use and allocation, as water demands from mining and industry are rising. Assessing water availability in this region and its relation with climatic variations is therefore crucial. The Dry Central Andes are characterised by a climatic setting different from that of the Alps and the subtropical Andes of Bolivia and Peru. Summers are very dry and stable, with precipitation close to zero and low relative humidity. Solar radiation is very intense, and plays a key role in the energy balance of snow covers and glaciers. The main aim of this study is to investigate the glacier-climate interaction in this area, with particular attention devoted to advanced modelling techniques for the spatial redistribution of meteorological variables, in order to gain an accurate picture of the ablation processes typical of these latitudes. During the ablation season 2005/2006, an extensive field campaign was conducted on the Juncal Norte glacier, aimed at monitoring the melt and runoff generation processes on this remote glacier in the dry Andes. Melt rates, runoff at the snout, meteorological variables over and near the glacier, GPS data and glacier topography were recorded over the entire ablation season. Using this extensive and accurate data set, the spatial and temporal variability of the meteorological variables that drive the melt process on the glacier is investigated, together with the process of runoff generation. An energy balance model is used to simulate melt across the glacier, and special attention is devoted to the modelling of the solar radiation energy flux. The components of the energy balance are compared with those of Alpine basins. The validity of parameterisations of the

  10. Rainfall-runoff modelling of the Okavango River catchment to assess impacts of land use change on runoff and downstream ecosystems

    Science.gov (United States)

    Milzow, Christian; Bauer-Gottwein, Peter

    2010-05-01

    The competition between human water use and ecosystem water use is one of the major challenges for water resources management at the global scale. We analyse the situation for the Okavango River basin of southern Africa. The Okavango River is representative for many large rivers throughout the developing world in that it is ungauged and poorly studied. The Okavango basin - spanning over Angola, Namibia and Botswana - represents a multi-objective problem in an international setting. Economic benefits of agricultural development and conservation of ecosystem services call for opposed actions. A semi-distributed rainfall-runoff model of the Okavango catchment is set up using the Soil and Water Assessment Tool (SWAT). The model is sufficiently physically based to simulate the impact on runoff of extent of agricultural use, crop types and management practices. Precipitation and temperature inputs are taken from datasets covering large parts of the globe. The methodology can thus easily be applied for other ungauged catchments. For temperature we use the ERA-Interim reanalysis product of the European Centre for Medium-Range Weather Forecasts and for precipitation the Famine Early Warning Systems Network data (FEWS-Net). Tropical Rainfall Measurement Mission (TRMM) data resulted in poor model performance compared to the FEWS-Net data. Presently, the upstream catchment in Angola is largely pristine and agriculture is basically restricted to dry land subsistence farming. But economic growth in Angola is likely to result in agricultural development and consequent impacts on catchment runoff. Land use scenarios that are simulated include large scale irrigated agriculture with water extractions from the river and the shallow aquifer. Climate change impacts are also studied and compared to land use change impacts. The downstream part of the basin consists of the large Okavango Wetlands, which are a biodiversity hotspot of global importance and, through tourism, an important

  11. Estimation of the possible flood discharge and volume of stormwater for designing water storage.

    Science.gov (United States)

    Kirzhner, Felix; Kadmon, Avri

    2011-01-01

    The shortage of good-quality water resources is an important issue in arid and semiarid zones. Stormwater-harvesting systems that are capable of delivering good-quality wastewater for non-potable uses while taking into account environmental and health requirements must be developed. For this reason, the availability of water resources of marginal quality, like stormwater, can be a significant contribution to the water supply. Current stormwater management practices in the world require the creation of control systems that monitor quality and quantity of the water and the development of stormwater basins to store increased runoff volumes. Public health and safety considerations should be considered. Urban and suburban development, with the creation of buildings and roads and innumerable related activities, turns rain and snow into unwitting agents of damage to our nation's waterways. This urban and suburban runoff, legally known as stormwater, is one of the most significant sources of water pollution in the world. Based on various factors like water quality, runoff flow rate and speed, and the topography involved, stormwater can be directed into basins, purification plants, or to the sea. Accurate floodplain maps are the key to better floodplain management. The aim of this work is to use geographic information systems (GIS) to monitor and control the effect of stormwater. The graphic and mapping capabilities of GIS provide strong tools for conveying information and forecasts of different storm-water flow and buildup scenarios. Analyses of hydrologic processes, rainfall simulations, and spatial patterns of water resources were performed with GIS, which means, based on integrated data set, the flow of the water was introduced into the GIS. Two cases in Israel were analyzed--the Hula Project (the Jordan River floods over the peat soil area) and the Kishon River floodplains as it existed in the Yizrael Valley.

  12. Comparing the impact of time displaced and biased precipitation estimates for online updated urban runoff models

    DEFF Research Database (Denmark)

    2013-01-01

    When an online runoff model is updated from system measurements, the requirements of the precipitation input change. Using rain gauge data as precipitation input there will be a displacement between the time when the rain hits the gauge and the time where the rain hits the actual catchment, due...... to the time it takes for the rain cell to travel from the rain gauge to the catchment. Since this time displacement is not present for system measurements the data assimilation scheme might already have updated the model to include the impact from the particular rain cell when the rain data is forced upon...... the model, which therefore will end up including the same rain twice in the model run. This paper compares forecast accuracy of updated models when using time displaced rain input to that of rain input with constant biases. This is done using a simple time-area model and historic rain series that are either...

  13. Comparison of two stochastic techniques for reliable urban runoff prediction by modeling systematic errors

    DEFF Research Database (Denmark)

    Del Giudice, Dario; Löwe, Roland; Madsen, Henrik;

    2015-01-01

    provide probabilistic predictions of wastewater discharge in a similarly reliable way, both for periods ranging from a few hours up to more than 1 week ahead of time. The EBD produces more accurate predictions on long horizons but relies on computationally heavy MCMC routines for parameter inferences......In urban rainfall-runoff, commonly applied statistical techniques for uncertainty quantification mostly ignore systematic output errors originating from simplified models and erroneous inputs. Consequently, the resulting predictive uncertainty is often unreliable. Our objective is to present two...

  14. How far can we go in hydrological modelling without any knowledge of runoff formation processes?

    Science.gov (United States)

    Ayzel, Georgy

    2016-04-01

    Hydrological modelling is a challenging scientific issue for the last 50 years and tend to be it further because of the highest level of runoff formation processes complexity at the different spatio-temporal scales. Enormous number of modelling-related papers have submitted to the top-ranked journals every year, but in this publication speed race authors have pay increasing attention to the models and data they use by itself rather than underlying watershed processes. Great community effort of the free and open-source models sharing with high availability of hydrometeorological data sources led to conceptual shifting paradigm of hydrological science to the technical-oriented direction. In the third-world countries this shifting is more clear by the reason of field studies absence and obligatory requirement of practical significance of the research supported by the government funds. As a result we get a state of hydrological modelling discipline closer to the aim of high Nash-Sutcliffe efficiency (NSE) achievement rather than watershed processes understanding. Both lumped physically-based land-surface model SWAP (Soil Water - Atmosphere - Plants) and SCE-UA (Shuffled Complex Evolution method developed at The University of Arizona) technique for robust model parameters search were used for the runoff modelling of 323 MOPEX watersheds. No one special data analysis and expert knowledge-based decisions were not performed. Median value of NSE is 0.652 and 90% of watersheds have efficiency bigger than 0.5. Thus without any information of particular features of each watershed satisfactory modelling results were obtained. To prove our conclusions we build cutting-edge conceptual rainfall-runoff model based on decision trees and adaptive boosting machine learning algorithms for the one small watershed in USA. No one special data analysis or feature engineering was not performed too. Obtained results demonstrate great model prediction power both for learning and testing

  15. Impediments and solutions to sustainable, watershed-scale urban stormwater management: lessons from Australia and the United States.

    Science.gov (United States)

    Roy, Allison H; Wenger, Seth J; Fletcher, Tim D; Walsh, Christopher J; Ladson, Anthony R; Shuster, William D; Thurston, Hale W; Brown, Rebekah R

    2008-08-01

    In urban and suburban areas, stormwater runoff is a primary stressor on surface waters. Conventional urban stormwater drainage systems often route runoff directly to streams and rivers, thus exacerbating pollutant inputs and hydrologic disturbance, and resulting in the degradation of ecosystem structure and function. Decentralized stormwater management tools, such as low impact development (LID) or water sensitive urban design (WSUD), may offer a more sustainable solution to stormwater management if implemented at a watershed scale. These tools are designed to pond, infiltrate, and harvest water at the source, encouraging evaporation, evapotranspiration, groundwater recharge, and re-use of stormwater. While there are numerous demonstrations of WSUD practices, there are few examples of widespread implementation at a watershed scale with