WorldWideScience

Sample records for stormwater retarding basins

  1. Ecohydraulic-driven real-time control of stormwater basins

    Science.gov (United States)

    Muschalla, Dirk; Vallet, Bertrand; Anctil, François; Lessard, Paul; Pelletier, Geneviève; Vanrolleghem, Peter A.

    2014-04-01

    Control of stormwater basins can be a competitive measure to improve the ecohydraulics of urban rivers by increasing the removal efficiency of particles and agglomerated contaminants like heavy metals and by decreasing hydraulic peak flows. In this paper, we present a simulation study that evaluates the potential of ecohydraulic-driven real-time control of stormwater basins to improve water quality and decrease hydraulic stress in the receiving water body. Nine different static and dynamic control scenarios were analysed based on a detailed hydraulic and quality model of an existing small urban catchment equipped with a stormwater basin at its outlet. Under dynamic control, an outlet valve was manipulated to increase retention time. The removal efficiency for suspended solids could be significantly increased by all control strategies and the hydraulic peaks were reduced by at least 50%. At the same time, overflow of the basin is avoided to prevent flooding. The developed dynamic control strategies proved to be advantageous as they provide significantly higher removal efficiency for suspended solids and a possible flexible adaptation to future demands. The findings of this study have been confirmed by field experiments.

  2. Characterising stormwater gross pollutants captured in catch basin inserts.

    Science.gov (United States)

    Alam, Md Zahanggir; Anwar, A H M Faisal; Sarker, Dipok Chandra; Heitz, Anna; Rothleitner, Craig

    2017-05-15

    The accumulation of wash-off solid waste, termed gross pollutants (GPs), in drainage systems has become a major constraint for best management practices (BMPs) of stormwater. GPs should be captured at source before the material clogs the drainage network, seals the infiltration capacity of side entry pits or affects the aquatic life in receiving waters. BMPs intended to reduce stormwater pollutants include oil and grit separators, grassed swales, vegetated filter strips, retention ponds, and catch basin inserts (CBIs) are used to remove GP at the source and have no extra land use requirement because they are typically mounted within a catch basin (e.g. side entry pits; grate or gully pits). In this study, a new type of CBI, recently developed by Urban Stormwater Technologies (UST) was studied for its performance at a site in Gosnells, Western Australia. This new type of CBI can capture pollutants down to particle sizes of 150μm while retaining its shape and pollutant capturing capacity for at least 1year. Data on GP and associated water samples were collected during monthly servicing of CBIs for one year. The main component of GPs was found to be vegetation (93%): its accumulation showed a strong relationship (r 2 =0.9) with rainfall especially during the wet season. The average accumulation of total GP load for each CBI was 384kg/ha/yr (dry mass) with the GP moisture content ranging from 24 to 52.5%. Analysis of grain sizes of GPs captured in each CBI showed similar distributions in the different CBIs. The loading rate coefficient (K) calculated from runoff and GP load showed higher K-values for CBI located near trees. The UST developed CBI in this study showed higher potential to capture GPs down to 150μm in diameter than similar CBI devices described in previous studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. The Role of Denitrification in Stormwater Detention Basin Treatment of Nitrogen.

    Science.gov (United States)

    Morse, Natalie R; McPhillips, Lauren E; Shapleigh, James P; Walter, M Todd

    2017-07-18

    The nitrogen (N) cycling dynamics of four stormwater basins, two often saturated sites ("Wet Basins") and two quick draining sites ("Dry Basins"), were monitored over a ∼ 1-year period. This study paired stormwater and greenhouse gas monitoring with microbial analyses to elucidate the mechanisms controlling N treatment. Annual dissolved inorganic N (DIN) mass reductions (inflow minus outflow) were greater in the Dry Basin than in the Wet Basin, 2.16 vs 0.75 g N m -2 yr -1 , respectively. The Dry Basin infiltrated a much larger volume of water and thus had greater DIN mass reductions, even though incoming and outgoing DIN concentrations were statistically the same for both sites. Wet Basins had higher proportions of denitrification genes and potential denitrification rates. The Wet Basin was capable of denitrifying 58% of incoming DIN, whereas the Dry Basin only denitrified 1%. These results emphasize the need for more mechanistic attention to basin design because the reductions calculated by comparing inflow and outflow loads may not be relevant at watershed scales. Denitrification is the only way to fully remove DIN from the terrestrial environment and receiving waterbodies. Consequently, at the watershed scale the Wet Basin may have better overall DIN treatment.

  4. Cyclic biogeochemical processes and nitrogen fate beneath a subtropical stormwater infiltration basin.

    Science.gov (United States)

    O'Reilly, Andrew M; Chang, Ni-Bin; Wanielista, Martin P

    2012-05-15

    A stormwater infiltration basin in north-central Florida, USA, was monitored from 2007 through 2008 to identify subsurface biogeochemical processes, with emphasis on N cycling, under the highly variable hydrologic conditions common in humid, subtropical climates. Cyclic variations in biogeochemical processes generally coincided with wet and dry hydrologic conditions. Oxidizing conditions in the subsurface persisted for about one month or less at the beginning of wet periods with dissolved O(2) and NO(3)(-) showing similar temporal patterns. Reducing conditions in the subsurface evolved during prolonged flooding of the basin. At about the same time O(2) and NO(3)(-) reduction concluded, Mn, Fe and SO(4)(2-) reduction began, with the onset of methanogenesis one month later. Reducing conditions persisted up to six months, continuing into subsequent dry periods until the next major oxidizing infiltration event. Evidence of denitrification in shallow groundwater at the site is supported by median NO(3)(-)-N less than 0.016 mg L(-1), excess N(2) up to 3 mg L(-1) progressively enriched in δ(15)N during prolonged basin flooding, and isotopically heavy δ(15)N and δ(18)O of NO(3)(-) (up to 25‰ and 15‰, respectively). Isotopic enrichment of newly infiltrated stormwater suggests denitrification was partially completed within two days. Soil and water chemistry data suggest that a biogeochemically active zone exists in the upper 1.4m of soil, where organic carbon was the likely electron donor supplied by organic matter in soil solids or dissolved in infiltrating stormwater. The cyclic nature of reducing conditions effectively controlled the N cycle, switching N fate beneath the basin from NO(3)(-) leaching to reduction in the shallow saturated zone. Results can inform design of functionalized soil amendments that could replace the native soil in a stormwater infiltration basin and mitigate potential NO(3)(-) leaching to groundwater by replicating the biogeochemical

  5. Spatial and Temporal Distribution of Polycyclic Aromatic Hydrocarbons and Heavy Metals in Stormwater Detention Basin Sediments

    Science.gov (United States)

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

    2015-12-01

    Stormwater runoff is a conduit for several pollutants such as polycyclic aromatic hydrocarbons (PAHs) into surface and ground water bodies. The control of runoff and pollutants is typically addressed by best management practices, such as retention/detention ponds. While the effectiveness of catchment basins in runoff volume reduction and removal of some contaminants has been established, very little is known about contaminant fate within these structures. Particularly in coastal regions and places with shallow groundwater tables PAH accumulation 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. Here, five stormwater catchment basins along the I-95 corridor in Rhode Island were selected based on the stormwater runoff origin and land use (industrial, urban, highway, and commercial). To study the stratification of PAHs one foot sediment cores were collected and analyzed for 17 PAHs (16 EPA parent PAH and Retene). The concentrations of PAHs in sediments of detention ponds in urban and industrial land use areas ranged from 20 μg/g to 200 μg/g. Generally higher concentrations of contaminants were found in sediments near the pond inlet and a decreasing concentration gradient is observed laterally and vertically throughout the pond. To compare stormwater ponds in various land use settings a new index based on sediment contamination, pond size and age, and catchment area will be presented. Further, it will be investigated whether BMP maintenance has to be targeted towards pollutant removal to maintain an effective stormwater treatment system.

  6. Indicators for hydraulic and pollution retention assessment of stormwater infiltration basins.

    Science.gov (United States)

    Dechesne, Magali; Barraud, Sylvie; Bardin, Jean-Pascal

    2004-07-01

    Infiltration basins are frequently used for stormwater management even though their long-term evolution is not well understood nor controlled. The two main problems encountered are clogging which compromises the hydraulic capacity of the basin and possible contamination of underlying soil and groundwater. This paper defines a framework for evaluating the hydraulic and pollution retention performance of infiltration basins in the long-term. Sets of context and performance indicators are proposed, along with two complementary modes of evaluation. Context indicators are identified in order to define the clogging and contamination states of the basins. Performance indicators are developed to assess several aspects of basin performance: drainage duration, overflow frequency, predictive life period, particle filtration and pollution trapping. Modes of evaluation include field investigation and long-term simulation modeling. Indicators are tested on five infiltration basins in suburban Lyon (France). Both context indicators and hydraulic performance indicators are reliable and their evaluation is representative of basin behavior. This is not the case for pollution retention performance indicators. Their assessment is difficult because of data quality. Field data has high uncertainties. The model is satisfactory for the hydraulic simulation and the evolution of clogging. Improvements are necessary for pollution flow simulation and the acquisition of better quality data is required.

  7. Nutrient removal using biosorption activated media: Preliminary biogeochemical assessment of an innovative stormwater infiltration basin

    International Nuclear Information System (INIS)

    O'Reilly, Andrew M.; Wanielista, Martin P.; Chang, Ni-Bin; Xuan, Zhemin; Harris, Willie G.

    2012-01-01

    Soil beneath a stormwater infiltration basin receiving runoff from a 23 ha predominantly residential watershed in north-central Florida, USA, was amended using biosorption activated media (BAM) to study the effectiveness of this technology in reducing inputs of nitrogen and phosphorus to groundwater. The functionalized soil amendment BAM consists of a 1.0:1.9:4.1 mixture (by volume) of tire crumb (to increase sorption capacity), silt and clay (to increase soil moisture retention), and sand (to promote sufficient infiltration), which was applied to develop an innovative stormwater infiltration basin utilizing nutrient reduction and flood control sub-basins. Comparison of nitrate/chloride (NO 3 − /Cl − ) ratios for the shallow groundwater indicates that prior to using BAM, NO 3 − concentrations were substantially influenced by nitrification or variations in NO 3 − input. In contrast, for the new basin utilizing BAM, NO 3 − /Cl − ratios indicate minor nitrification and NO 3 − losses with the exception of one summer sample that indicated a 45% loss. Biogeochemical indicators (denitrifier activity derived from real-time polymerase chain reaction and variations in major ions, nutrients, dissolved and soil gases, and stable isotopes) suggest that NO 3 − losses are primarily attributable to denitrification, whereas dissimilatory nitrate reduction to ammonium is a minor process. Denitrification was likely occurring intermittently in anoxic microsites in the unsaturated zone, which was enhanced by the increased soil moisture within the BAM layer and resultant reductions in surface/subsurface oxygen exchange that produced conditions conducive to increased denitrifier activity. Concentrations of total dissolved phosphorus and orthophosphate (PO 4 3− ) were reduced by more than 70% in unsaturated zone soil water, with the largest decreases in the BAM layer where sorption was the most likely mechanism for removal. Post-BAM PO 4 3− /Cl − ratios for shallow

  8. Stormwater solids removal characteristics of a catch basin insert using geotextile.

    Science.gov (United States)

    Alam, Md Zahanggir; Anwar, A H M Faisal; Heitz, Anna

    2018-03-15

    Suspended solids in urban runoff have multiple adverse environmental impacts and create a wide range of water quality problems in receiving water bodies. Geotextile filtration systems inserted within catch basins have the potential to mitigate these effects, through flow attenuation and pollutant removal. This study modelled a catch basin in a column and assessed the hydraulic and solids removal characteristics of a new type of non-woven geotextile (NWG1) in the capture of solids from stormwater runoff. The new geotextile was compared with two others readily available on the market (NWG2, NWG3). Synthetic stormwater containing TSS (200mg/L) was used with two particle size distributions of 0-180μm (P1; D 50 :106μm) and 0-300μm (P2; D 50 :150μm). The results revealed that the desired stormwater TSS concentration (soil with the larger range of particle sizes (P2) than for the soil with smaller particle sizes (P1). Geotextile fibre pattern appeared to have a significant influence on the TSS removal capacity. The NWG1 has higher permittivity than NWG3 but similar to NWG2. NWG1 could capture overall more TSS (which also resulted in earlier clogging) than NWG2 and NWG3 because of the special fibre structure of NWG1. The experimental data shows that these geotextiles may start to clog when the hydraulic conductivity reaches below 1.36×10 -5 m/s. The overall hydraulic performances of geotextiles showed that the NWG1 has better potential for use in CBIs because of its higher strength and multiple reuse capability. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Dynamics of dissolved organic carbon (DOC) through stormwater basins designed for groundwater recharge in urban area: Assessment of retention efficiency.

    Science.gov (United States)

    Mermillod-Blondin, Florian; Simon, Laurent; Maazouzi, Chafik; Foulquier, Arnaud; Delolme, Cécile; Marmonier, Pierre

    2015-09-15

    Managed aquifer recharge (MAR) has been developed in many countries to limit the risk of urban flooding and compensate for reduced groundwater recharge in urban areas. The environmental performances of MAR systems like infiltration basins depend on the efficiency of soil and vadose zone to retain stormwater-derived contaminants. However, these performances need to be finely evaluated for stormwater-derived dissolved organic matter (DOM) that can affect groundwater quality. Therefore, this study examined the performance of MAR systems to process DOM during its transfer from infiltration basins to an urban aquifer. DOM characteristics (fluorescent spectroscopic properties, biodegradable and refractory fractions of dissolved organic carbon -DOC-, consumption by micro-organisms during incubation in slow filtration sediment columns) were measured in stormwater during its transfer through three infiltration basins during a stormwater event. DOC concentrations sharply decreased from surface to the aquifer for the three MAR sites. This pattern was largely due to the retention of biodegradable DOC which was more than 75% for the three MAR sites, whereas the retention of refractory DOC was more variable and globally less important (from 18% to 61% depending on MAR site). Slow filtration column experiments also showed that DOC retention during stormwater infiltration through soil and vadose zone was mainly due to aerobic microbial consumption of the biodegradable fraction of DOC. In parallel, measurements of DOM characteristics from groundwaters influenced or not by MAR demonstrated that stormwater infiltration increased DOC quantity without affecting its quality (% of biodegradable DOC and relative aromatic carbon content -estimated by SUVA254-). The present study demonstrated that processes occurring in soil and vadose zone of MAR sites were enough efficient to limit DOC fluxes to the aquifer. Nevertheless, the enrichments of DOC concentrations measured in groundwater below

  10. 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

  11. Stormwater quality characteristics in (Dutch) urban areas and performance of settlement basins

    NARCIS (Netherlands)

    Boogaard, F.C.; Van de Ven, F.; Langeveld, J.G.; Van de Giesen, N.

    2014-01-01

    Stormwaters, flowing into storm sewers, are known to significantly increase the annual pollutant loads entering urban receiving waters and this results in significant degradation of the receiving water quality. Knowledge of the characteristics of stormwater pollution enables urban planners to

  12. Pesticides and pesticide degradation products in stormwater runoff: Sacramento River Basin, California

    Science.gov (United States)

    Domagalski, Joseph L.

    1996-01-01

    Pesticides in stormwater runoff, within the Sacramento River Basin, California, were assessed during a storm that occurred in January 1994. Two organophosphate insecticides (diazinon and methidathion), two carbamate pesticides (molinate and carbofuran), and one triazine herbicide (simazine) were detected. Organophosphate pesticide concentrations increased with the rising stage of the hydrographs; peak concentrations were measured near peak discharge. Diazinon oxon, a toxic degradation product of diazinon, made up approximately 1 to 3 percent of the diazinon load. The Feather River was the principal source of organophosphate pesticides to the Sacramento River during this storm. The concentrations of molinate and carbofuran, pesticides applied to rice fields during May and June, were relatively constant during and after the storm. Their presence in surface water was attributed to the flooding and subsequent drainage, as a management practice to degrade rice stubble prior to the next planting. A photodegradation product of molinate, 4-keto molinate, was in all samples where molinate was detected and made up approximately 50 percent of the total molinate load. Simazine, a herbicide used in orchards and to control weeds along the roadways, was detected in the storm runoff, but it was not possible to differentiate the two sources of that pesticide to the Sacramento River.

  13. Stormwater Quality Characteristics in (Dutch Urban Areas and Performance of Settlement Basins

    Directory of Open Access Journals (Sweden)

    Floris C. Boogaard

    2014-03-01

    Full Text Available Stormwaters, flowing into storm sewers, are known to significantly increase the annual pollutant loads entering urban receiving waters and this results in significant degradation of the receiving water quality. Knowledge of the characteristics of stormwater pollution enables urban planners to incorporate the most appropriate stormwater management strategies to mitigate the effects of stormwater pollution on downstream receiving waters. This requires detailed information on stormwater quality, such as pollutant types, sediment particle size distributions, and how soluble pollutants and heavy metals attach themselves to sediment particles. This study monitored stormwater pollution levels at over 150 locations throughout the Netherlands. The monitoring has been ongoing for nearly 15 years and a total of 7,652 individual events have been monitored to date. This makes the database the largest stormwater quality database in Europe. The study compared the results to those presented in contemporary international stormwater quality research literature. The study found that the pollution levels at many of the Dutch test sites did not meet the requirements of the European Water Framework Directive (WFD and Dutch Water Quality Standards. Results of the study are presented and recommendations are made on how to improve water quality with the implementation of Sustainable Urban Drainage Systems (SUDS devices.

  14. Evaluation of Street Sweeping as a Stormwater-Quality-Management Tool in Three Residential Basins in Madison, Wisconsin

    Science.gov (United States)

    Selbig, William R.; Bannerman, Roger T.

    2007-01-01

    Recent technological improvements have increased the ability of street sweepers to remove sediment and other debris from street surfaces; the effect of these technological advancements on stormwater quality is largely unknown. The U.S. Geological Survey, in cooperation with the City of Madison and the Wisconsin Department of Natural Resources, evaluated three street-sweeper technologies from 2002 through 2006. Regenerative-air, vacuum-assist, and mechanical-broom street sweepers were operated on a frequency of once per week (high frequency) in separate residential basins in Madison, Wis., to measure each sweeper's ability to not only reduce street-dirt yield but also improve the quality of stormwater runoff. A second mechanical-broom sweeper operating on a frequency of once per month (low frequency) was also evaluated to measure reductions in street-dirt yield only. A paired-basin study design was used to compare street-dirt and stormwater-quality samples during a calibration (no sweeping) and a treatment period (weekly sweeping). The basis of this paired-basin approach is that the relation between paired street-dirt and stormwater-quality loads for the control and tests basins is constant until a major change is made at one of the basins. At that time, a new relation will develop. Changes in either street-dirt and/or stormwater quality as a result of street sweeping could then be quantified by use of statistical tests. Street-dirt samples collected weekly during the calibration period and twice per week during the treatment period, once before and once after sweeping, were dried and separated into seven particle-size fractions ranging from less than 63 micrometers to greater than 2 millimeters. Street-dirt yield evaluation was based on a computed mass per unit length of pounds per curb-mile. An analysis of covariance was used to measure the significance of the effect of street sweeping at the end of the treatment period and to quantify any reduction in street

  15. 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.

  16. Occurrence of halogenated and organophosphate flame retardants in sediment and fish samples from three European river basins

    OpenAIRE

    Giulivo, Monica; Capri, Ettore; Kalogianni, Eleni; Milačič, Radmila; Majone, Bruno; Ferrari, Federico; Eljarrat, Ethel; Barceló, Damià

    2017-01-01

    Classic (polybromodiphenyl ethers, PBDEs) and emerging halogenated flame retardants (HFRs) such as decabromodiphenyl ethane (DBDPE) and halogenated norbornenes, as well as organophosphate flame retardants (OPFRs) were analysed in 52 sediments and 27 fish samples from three European river basins, namely the Evrotas (Greece), the Adige (Italy) and the Sava (Slovenia, Croatia, Bosnia and Herzegovina and Serbia). This is the first time that FR levels have been reported in these three European riv...

  17. Effects of stormwater infiltration on quality of groundwater beneath retention and detention basins

    Science.gov (United States)

    Fischer, D.; Charles, E.G.; Baehr, A.L.

    2003-01-01

    Infiltration of storm water through detention and retention basins may increase the risk of groundwater contamination, especially in areas where the soil is sandy and the water table shallow, and contaminants may not have a chance to degrade or sorb onto soil particles before reaching the saturated zone. Groundwater from 16 monitoring wells installed in basins in southern New Jersey was compared to the quality of shallow groundwater from 30 wells in areas of new-urban land use. Basin groundwater contained much lower levels of dissolved oxygen, which affected concentrations of major ions. Patterns of volatile organic compound and pesticide occurrence in basin groundwater reflected the land use in the drainage areas served by the basins, and differed from patterns in background samples, exhibiting a greater occurrence of petroleum hydrocarbons and certain pesticides. Dilution effects and volatilization likely decrease the concentration and detection frequency of certain compounds commonly found in background groundwater. High recharge rates in storm water basins may cause loading factors to be substantial even when constituent concentrations in infiltrating storm water are relatively low.

  18. Urban Mosquito Fauna in Mérida City, México: Immatures Collected from Containers and Storm-water Drains/Catch Basins

    Science.gov (United States)

    Baak-Baak, Carlos M.; Arana-Guardia, Roger; Cigarroa-Toledo, Nohemi; Puc-Tinal, María; Coba-Tún, Carlos; Rivero-Osorno, Víctor; Lavalle-Kantun, Damián; Loroño-Pino, María Alba; Machain-Williams, Carlos; Reyes-Solis, Guadalupe C.; Beaty, Barry J.; Eisen, Lars; García-Rejón, Julián E.

    2014-01-01

    We examined the species composition and temporal occurrence of immature mosquitoes in containers and storm-water drains/catch basins from November 2011 to June 2013 in Mérida City, México. A wide range of urban settings were examined, including residential premises, vacant lots, parking lots, and streets or sidewalks with storm-water drains/catch basins. In total, 111,776 specimens of 15 species were recorded. The most commonly collected species were Aedes (Stegomyia) aegypti (L.) (n = 60,961) and Culex quinquefasciatus Say (45,702), which together accounted for 95.4% of the immatures collected. These species were commonly encountered during both rainy and dry seasons, whereas most other mosquito species were collected primarily during the rainy season. Other species collected were Aedes (Howardina) cozumelensis Diaz Najera, Aedes (Ochlerotatus) taeniorhynchus (Wiedemann), Aedes (Ochlerotatus) trivittatus (Coquillett), Culex coronator Dyar and Knab, Culex interrogator Dyar and Knab, Culex lactator Dyar and Knab, Culex nigripalpus Theobald, Culex salinarius Coquillett, Culex tarsalis Coquillett, Culex thriambus Dyar, Haemagogus equinus Theobald, Limatus durhamii Theobald, and Toxorhynchites rutilus (Coquillett). The greatest number of species was recorded from vacant lots (n = 11), followed by storm-water drains/catch basins (nine) and residential premises (six). Our study demonstrated that the heterogeneous urban environment in Mérida City supports a wide range of mosquito species, many of which are nuisance biters of humans and/or capable of serving as vectors of pathogens affecting humans or domestic animals. We also briefly reviewed the medical importance of the encountered mosquito species. PMID:25429168

  19. Review on physical and chemical characterizations of contaminated sediments from urban stormwater infiltration basins within the framework of the French observatory for urban hydrology (SOERE URBIS).

    Science.gov (United States)

    El-Mufleh, Amelène; Béchet, Béatrice; Ruban, Véronique; Legret, Michel; Clozel, Blandine; Barraud, Sylvie; Gonzalez-Merchan, Carolina; Bedell, Jean-Philippe; Delolme, Cécile

    2014-04-01

    Urban stormwater infiltration basins are designed to hold runoff from impervious surfaces and allow the settling of sediments and associated pollutants. However concerns have been expressed about the environmental impacts that may be exerted by the trapped pollutants on groundwater, soils and ecosystems. In this context, sediment characterization represents a key issue for local authorities in terms of management strategies. During the last two decades, several studies were launched including either physical or chemical characterization of stormwater sediments but without real synthesis of data and methods used. Consequently, there is an important need for reviewing the current experimental techniques devoted to the physico-chemical characterization of sediment. The review is based on the outcomes of two experimental sites for which long term monitoring and data collection have been done: the Cheviré basin (near Nantes) and the Django Reinhardt basin (near Lyon). The authors summarize the studies dealing with bulk properties, pollutant contents, their potential mobility and speciation. This paper aims at promoting the significant progresses that were made through a multidisciplinary approach involving multi-scaled and combined experimental techniques.

  20. Complex interactions among nutrients, chlorophyll-a, and microcystins in three stormwater wet detention basins with floating treatment wetlands.

    Science.gov (United States)

    Hartshorn, Nicholas; Marimon, Zachary; Xuan, Zhemin; Cormier, Jessica; Chang, Ni-Bin; Wanielista, Martin

    2016-02-01

    Stormwater wet detention ponds hold a permanent pool of water and offer many beneficial uses including flood mitigation, pollution prevention, downstream erosion control, increased aesthetics, and recreational uses. Although the removal of nutrients is generally low for stormwater wet detention ponds in urban areas, floating treatment wetlands (FTWs) can be installed to offer an innovative solution toward naturally removing excess nutrients and aiding in stormwater management. To improve the stormwater reuse potential, this study assessed nutrient, microcystin, and chlorophyll-a interactions in three Florida stormwater wet detention ponds with recently implemented FTWs. Both episodic (storm events) and routine (non-storm events) sampling campaigns were carried out at the three ponds located in Ruskin, Gainesville, and Orlando. The results showed a salient negative correlation between total phosphorus and microcystin concentrations for both storm and non-storm events across all three ponds. The dominant nutrient species in correlation seemed to be total phosphorus, which correlated positively with chlorophyll-a concentrations at all ponds and sampling conditions, with the exception of Orlando non-storm events. These results showed a correlation conditional to the candidate pond and sampling conditions for microcystin and chlorophyll-a concentrations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Stormwater management and ecosystem services: a review

    Science.gov (United States)

    Prudencio, Liana; Null, Sarah E.

    2018-03-01

    Researchers and water managers have turned to green stormwater infrastructure, such as bioswales, retention basins, wetlands, rain gardens, and urban green spaces to reduce flooding, augment surface water supplies, recharge groundwater, and improve water quality. It is increasingly clear that green stormwater infrastructure not only controls stormwater volume and timing, but also promotes ecosystem services, which are the benefits that ecosystems provide to humans. Yet there has been little synthesis focused on understanding how green stormwater management affects ecosystem services. The objectives of this paper are to review and synthesize published literature on ecosystem services and green stormwater infrastructure and identify gaps in research and understanding, establishing a foundation for research at the intersection of ecosystems services and green stormwater management. We reviewed 170 publications on stormwater management and ecosystem services, and summarized the state-of-the-science categorized by the four types of ecosystem services. Major findings show that: (1) most research was conducted at the parcel-scale and should expand to larger scales to more closely understand green stormwater infrastructure impacts, (2) nearly a third of papers developed frameworks for implementing green stormwater infrastructure and highlighted barriers, (3) papers discussed ecosystem services, but less than 40% quantified ecosystem services, (4) no geographic trends emerged, indicating interest in applying green stormwater infrastructure across different contexts, (5) studies increasingly integrate engineering, physical science, and social science approaches for holistic understanding, and (6) standardizing green stormwater infrastructure terminology would provide a more cohesive field of study than the diverse and often redundant terminology currently in use. We recommend that future research provide metrics and quantify ecosystem services, integrate disciplines to

  2. Stormwater pollution treatment BMP discharge structures.

    Science.gov (United States)

    2014-03-01

    Structural best management practices (BMPs) are used to capture and treat stormwater runoff. Most structural BMPs provide treatment by filtering : runoff through a filter media or collecting it in a detention basin and slowly discharging it over an e...

  3. Role of the sedimentary structure of the urban vadose zone (URVAZO) on the transfer of heavy metals of an urban stormwater basin

    Science.gov (United States)

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

    2009-12-01

    Stormwater infiltration basins have become a common alternative practice to traditional stormwater pipe networks in urban areas. They are often built in permeable subsurface soils (Urban Vadose Zone, URVAZO), such as alluvial deposits. These sedimentary deposits are highly heterogeneous and generate preferential flow paths that may cause either rapid or non-uniform transport of contaminants at great depths. The understanding of how subsurface vadose zone heterogeneities transfer contaminant and fluid flow to the aquifer still remains a challenge in urban hydrology. Indeed, urban stormwater may contain pollutants that can contaminate either soil or groundwater. The aim of this study is to evaluate the role of the lithological heterogeneity of a glaciofluvial deposit underlying an urban infiltration basin on the link between water flow and heavy metals retention. A trench wall (14m length x 3m depth) was exposed by excavating the glaciofluvial formation. By a hydrogeophysical approach based on a sedimentary structural units and in situ hydraulic characterization (Beerkan tests), a realistic hydrostratigraphic 2D model was defined. The trench was sampled on nine vertical sections of 1.5m length, with ten samples per vertical section following each lithofacies. A total of 90 samples were analyzed. Coarse (mechanical sieving) and fine (laser diffraction) particle size distribution analysis, as well as the concentration of three replicates of Pb, Cu, Zn and organic matter (OM) was measured for each sample. The principal component analysis shows a strong correlation between metal concentration and the lithofacies. This hydrostratigraphic model was implemented in the finite element program Hydrus2D. The soil heterogeneity exerts an impact on the heterogeneity of the water content field under slightly saturated conditions, as they induce capillary barrier effects. These capillary barrier effects may generate water accumulation in some lithofacies overlying matrix

  4. Sources of phosphorus in stormwater and street dirt from two urban residential basins in Madison, Wisconsin, 1994-95

    Science.gov (United States)

    Waschbusch, Robert J.; Selbig, W.R.; Bannerman, Roger T.

    1999-01-01

    Eutrophication is a common problem for lakes in agricultural and urban areas, such as Lakes Wingra and Mendota in Madison, Wisconsin. This report describes a study to estimate the sources of phosphorus, a major contributor to eutrophication, to Lakes Wingra and Mendota from two small urban residential drainage basins. The Monroe Basin empties into Lake Wingra, and the Harper Basin into Lake Mendota. Phosphorus data were collected from streets, lawns, roofs, driveways, and parking lots (source areas) within these two basins and were used to estimate loads from each area. In addition to the samples collected from these source areas, flow-composite samples were collected at monitoring stations located at the watershed outfalls (storm sewers); discharge and rainfall also were measured. Resulting data were then used to calibrate the Source Loading and Management Model (SLAMM, version 6.3, copyright 1993, Pitt & Vorhees) for conditions in the city of Madison and determine within these basins which of the source areas are contributing the most phosphorus.

  5. Optimal design of stormwater basins with bio-sorption activated media (BAM) in karst environments - phase I : site screening and selection.

    Science.gov (United States)

    2015-12-01

    Anthropogenic activities within the Silver Springs springshed over recent decades may have contributed : to elevated nutrient concentrations in stormwater runoff and groundwater, leading to the eutrophication : of Silver Springs. To remove the nutrie...

  6. Stormwater Drainage Wells

    Science.gov (United States)

    Provides information for identifying stormwater drainage wells, learn how to comply with regulations for storm water drainage wells, and how to reduce the threat to ground water from stormwater injection wells.

  7. Stormwater Calculator (SWC) webinar

    Science.gov (United States)

    Jason Berner presents EPA’s National Stormwater Calculator developed to help support local, state and national stormwater management objectives and regulatory efforts to reduce runoff using green infrastructure practices as low impact development controls.

  8. Monitoring Stormwater Management Controls

    Science.gov (United States)

    Nationally, we are investing billions of dollars in green stormwater management but cannot provide assurances that the stormwater controls perform as intended in the long term. We need to develop a consistent set of measurements confirming that the stormwater management practice...

  9. Occurrence of classic and emerging halogenated flame retardants in sediment and sludge from Ebro and Llobregat river basins (Spain).

    Science.gov (United States)

    Barón, Enrique; Santín, Giselle; Eljarrat, Ethel; Barceló, Damià

    2014-01-30

    Classic (polybromodiphenyl ethers, PBDEs) and emerging halogenated flame retardants such as hexabromobenzene (HBB), pentabromoetilbenzene (PBEB), decabromodiphenyl ethane (DBDPE), Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603), Dechlorane 604 (Dec 604) and Dechlorane plus (DP) were analyzed in 33 sediments and 7 sludges from two Iberian river basins, Ebro and Llobregat. In sediment samples, PBDE levels ranged between nd and 44.3ng/g dw with BDE-209 being the most abundant congener. Levels of DBDPE and halogenated norbornenes ranged between nd and 31.5ng/g dw and between nq and 3.74ng/g dw, respectively. This is the first study to report halogenated norbornene levels in sediment samples from Spain. PBDE, DBDPE and halogenated norbornene levels in sludge ranged from 13 to 340, nq to 124 and 2.7 to 19ng/g dw, respectively. HBB and PBEB were not detected in any sample. Levels of classic and emerging HFRs were compared. Our results suggest that DBDPE is the most frequently used compound to replace BDE-209, whereas the use of halogenated norbornenes is still low. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. From headwaters to estuary: Distribution and fate of halogenated flame retardants (HFRs) in a river basin near the largest HFR manufacturing base in China.

    Science.gov (United States)

    Zhen, Xiaomei; Tang, Jianhui; Liu, Lin; Wang, Xinming; Li, Yanan; Xie, Zhiyong

    2018-04-15

    With the gradual phasing out of polybrominated diphenyl ethers (PBDEs), market demands for alternative halogenated flame retardants (HFRs) are increasing. The Laizhou Bay area is the biggest manufacturing base for brominated flame retardants (BFRs) in China, and the Xiaoqing River is the largest and most heavily contaminated river in this region. Water and sediment samples were collected from the headwaters to the estuary of the Xiaoqing River to investigate the distribution and fate of HFRs [i.e., PBDEs, alternative brominated flame retardants (aBFRs) and dechlorane plus (DPs). In the water samples, DPs was the most abundant flame retardant (median: 11.7ng/L), followed by decabromodiphenylethane (DBDPE) (5.92ng/L). In the sediment samples, DBDPE was the predominant flame retardant (39.5ng/g dw), followed by decabromodiphenyl ether (BDE 209) (2.81ng/g dw). The levels of DBDPE exceeded those of BDE 209 in most samples, indicating the overwhelming replacement of BDE 209 by DBDPE in this area. In the river section of this study, point source and atmospheric deposition followed by land runoff were the major factors influencing the distribution of HFRs, whereas in the estuary, riverine discharge, the estuarine maximum turbidity zone (MTZ), and hydrodynamic parameters played more important roles. Manufacturing is a significant source of contamination of the Xiaoqing River basin through atmospheric deposition and wastewater discharge. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. National Stormwater Calculator: Low Impact Development Stormwater Control Cost Estimation

    Science.gov (United States)

    Stormwater discharges continue to cause impairment of our Nation’s waterbodies. EPA has developed the National Stormwater Calculator (SWC) to help support local, state, and national stormwater management objectives to reduce runoff through infiltration and retention using green i...

  12. Uncertainties of stormwater characteristics and removal rates of stormwater treatment facilities: Implications for stormwater treatment facilities : Implications for stormwater handling

    NARCIS (Netherlands)

    J.G. Langeveld; H.J. Liefting; ir. Floris Boogaard

    2012-01-01

    This study focuses on 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

  13. EPA's National Stormwater Calculator (Poster)

    Science.gov (United States)

    This poster will demonstrate how EPA's National Stormwater Calculator works. The National Stormwater Calculator (SWC) estimates the amount of stormwater runoff generated from a site under different development and control scenarios over a long period of historical rainfall. The a...

  14. Stormwater Permits - Pending Permits

    Data.gov (United States)

    Vermont Center for Geographic Information — This layer contains pending permits by the Stormwater Management Program for impervious surfaces (operational permits) or industrial activities (MSGP). Construction...

  15. Brominated Flame Retardants: Spatial and Temporal Trends in the Environment and Biota from the Pacific Basin Countries

    Science.gov (United States)

    Brominated flame retardants (BFRs) are used as additive or reactive components in a variety of polymers including high-impact polystyrene and epoxy resins, commercial products such as computers, electronics and electrical equipment, thermal insulation, textiles and furniture foam...

  16. Effects of urban development on stormwater runoff characteristics for the Houston, Texas, metropolitan area

    Science.gov (United States)

    Liscum, Fred

    2001-01-01

    A study was done to estimate the effects of urban development in the Houston, Texas, metropolitan area on nine stormwater runoff characteristics. Three of the nine characteristics define the magnitude of stormwater runoff, and the remaining six characteristics describe the shape and duration of a storm hydrograph. Multiple linear regression was used to develop equations to estimate the nine stormwater runoff characteristics from basin and rainfall characteristics. Five basin characteristics and five rainfall characteristics were tested in the regressions to determine which basin and rainfall characteristics significantly affect stormwater runoff characteristics. Basin development factor was found to be significant in equations for eight of the nine stormwater runoff characteristics. Two sets of equations were developed, one for each of two regions based on soil type, from a database containing 1,089 storm discharge hydrographs for 42 sites compiled during 1964–89.The effects of urban development on the eight stormwater runoff characteristics were quantified by varying basin development factor in the equations and recomputing the stormwater runoff characteristics. The largest observed increase in basin development factor for region 1 (north of Buffalo Bayou) during the study resulted in corresponding increases in the characteristics that define magnitude of stormwater runoff ranging from about 40 percent (for direct runoff) to 235 percent (for peak yield); and corresponding decreases in the characteristics that describe hydrograph shape and duration ranging from about 22 percent (for direct runoff duration) to about 58 percent (for basin lag). The largest observed increase in basin development factor for region 2 (south of Buffalo Bayou) during the study resulted in corresponding increases in the characteristics that define magnitude of stormwater runoff ranging from about 33 percent (for direct runoff) to about 210 percent (for both peak flow and peak yield

  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. National Stormwater Calculator

    Science.gov (United States)

    EPA’s National Stormwater Calculator (SWC) is a desktop application that estimates the annual amount of rainwater and frequency of runoff from a specific site anywhere in the United States (including Puerto Rico).

  19. Spatial and Temporal Variation in Local Stormwater Infrastructure Use and Stormwater Management Paradigms over the 20th Century

    Directory of Open Access Journals (Sweden)

    Rebecca L. Hale

    2016-07-01

    Full Text Available Stormwater management has significant consequences for urban hydrology, water quality, and flood risk, and has changed substantially over history, but it is unknown how these paradigm shifts play out at the local scale and whether local changes in stormwater infrastructure use follow similar trajectories across cities. This research addressed: (1 How does current infrastructure use and past infrastructure transitions vary across three cities with similar biophysical and climatic contexts but different development histories? and (2 How did stormwater and flood management paradigms change from early urbanization to current day in a single city? The use of storm sewers, detention basins, and canals for stormwater management was quantified for three cities in Utah, USA, over the 20th century. Stormwater management paradigms were quantified using media content analysis of newspaper articles from historic and recent periods in Salt Lake City. Results suggest that stormwater infrastructure development is decoupled from imperviousness across cities, and that newer and smaller cities follow different trajectories of stormwater management over time. This research highlights that there is no single model of urban hydrology and that heterogeneity in urban water management over time and space reflects shifting priorities and social learning.

  20. Developing a Successful Stormwater Program: Urban Forestry and Stormwater Mitigation

    OpenAIRE

    Lake, Matthew; Korthals, Reggie

    2015-01-01

    Trees can be incorporated into a public stormwater management program, contribute to compliance with MS4 regulations, and be managed to maximize their significant stormwater benefits. Details on state and local stormwater regulatory requirements will be presented as well as the valuable relationship between urban forest management, green street concepts, and stormwater compliance. Additionally, the challenges of budgeting for urban forest management, coordinating with other departments, and s...

  1. Dissolved Pesticide Concentrations Detected in Storm-Water Runoff at Selected Sites in the San Joaquin River Basin, California, 2000-2001

    National Research Council Canada - National Science Library

    Orlando, James L; Kuivila, Kathryn M; Whitehead, Andrew

    2003-01-01

    ...) and the University of California Davis Bodega Marine Laboratory (BML) water samples were collected at three sites within the San Joaquin River Basin of California and analyzed for dissolved pesticides...

  2. Selected chemical characteristics and acute toxicity of urban stormwater, streamflow, and bed material, Maricopa County, Arizona

    Science.gov (United States)

    Lopes, T.J.; Fossum, K.D.

    1995-01-01

    Statistical analyses indicated that urban stormwater could degrade the quality of streamflow because of oil and grease, pesticides, dissolved trace metals, and ammonia in stormwater. Ammonia, lead, cadmium, and zinc are released by urban activities and accumulate in bed material. Ammonia could be from fertilizers, fecal matter, and other sources. Lead is probably from vehicles that use leaded gasoline. Cadmium and zinc could be from particulate metal in oil, brake pads, and other sources. Samples of the initial runoff from urban drainage basins appeared to be more toxic than flow-weighted composite samples, and stormwater was more harmful to fathead minnows than to Ceriodaphnia dubia. Streamflow samples from the Salt River were not toxic to either species. The sensitivity of fathead minnows to urban stormwater from most urban drainage basins indicated that the toxicants were detrimental to fish and could be present in stormwater throughout Phoenix. Results of toxicity identification evaluations indicated the toxicity was mostly due to organic constituents. Mortality, however, did not correlate with organophosphate pesticide concentrations. Surfactants and (or) other constituents leached from asphalt could be toxic. The most toxic bed-material samples were collected from an undeveloped drainage basin. Within urban-drainage basins, bed-material samples collected where stormwater accumulates appeared to be more toxic than samples collected from areas unaffected by stormwater. Mortality rates correlated with recoverable concentrations of zinc, copper, and cadmium; however these rates correlated poorly with pesticide concentrations. The bioavailability of trace metals appeared to be controlled by the adsorption properties of bed material.

  3. Literature Review of Low Impact Development for Stormwater Control

    Science.gov (United States)

    2015-05-30

    contained in the paint particles. 7 2.1.2 Ship Building and Maintenance at Dry Docks Dry docks, also known as graving docks, are narrow concrete basins...closed by gates or by caissons. A vessel may be floated into the concrete basin and the water pumped out, leaving the vessel supported by blocks...docks are impermeable surfaces that may span multiple acres, rain events can generate very large volumes of stormwater runoff, which may be heavily

  4. Replacing natural wetlands with stormwater management facilities: Biophysical and perceived social values.

    Science.gov (United States)

    Rooney, R C; Foote, L; Krogman, N; Pattison, J K; Wilson, M J; Bayley, S E

    2015-04-15

    Urban expansion replaces wetlands of natural origin with artificial stormwater management facilities. The literature suggests that efforts to mimic natural wetlands in the design of stormwater facilities can expand the provision of ecosystem services. Policy developments seek to capitalize on these improvements, encouraging developers to build stormwater wetlands in place of stormwater ponds; however, few have compared the biophysical values and social perceptions of these created wetlands to those of the natural wetlands they are replacing. We compared four types of wetlands: natural references sites, natural wetlands impacted by agriculture, created stormwater wetlands, and created stormwater ponds. We anticipated that they would exhibit a gradient in biodiversity, ecological integrity, chemical and hydrologic stress. We further anticipated that perceived values would mirror measured biophysical values. We found higher biophysical values associated with wetlands of natural origin (both reference and agriculturally impacted). The biophysical values of stormwater wetlands and stormwater ponds were lower and indistinguishable from one another. The perceived wetland values assessed by the public differed from the observed biophysical values. This has important policy implications, as the public are not likely to perceive the loss of values associated with the replacement of natural wetlands with created stormwater management facilities. We conclude that 1) agriculturally impacted wetlands provide biophysical values equivalent to those of natural wetlands, meaning that land use alone is not a great predictor of wetland value; 2) stormwater wetlands are not a substantive improvement over stormwater ponds, relative to wetlands of natural origin; 3) stormwater wetlands are poor mimics of natural wetlands, likely due to fundamental distinctions in terms of basin morphology, temporal variation in hydrology, ground water connectivity, and landscape position; 4) these

  5. Urban Stormwater Infiltration Perspectives

    DEFF Research Database (Denmark)

    Geldof, Govert; Jacobsen, Per; Fujita, Shoichi

    1994-01-01

    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...

  6. 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.

  7. Review of stormwater management practices

    OpenAIRE

    Raspati, Gema Sakti; Azrague, Kamal; Jotte, Lensa

    2017-01-01

    Actual stormwater management involves the direct removal of surface water through a series of pipes to the nearest watercourse to prevent local flooding. Due to climate change and urbanisation stormwater volumes and pollution are getting more and more important leading to significant loads of sediments, heavy metals, nutrients, oils, grease, bacteria and salt pollutants which deteriorate the receiving water bodies. Consequently, modern stormwater management should aim at both flood control an...

  8. Urban Stormwater Infiltration Perspectives

    DEFF Research Database (Denmark)

    Geldof, Govert; Jacobsen, Per; Fujita, Shoichi

    1994-01-01

    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....... The second study concerns combined sewer overflows and the discharge from treatment plants for catchments in Denmark and the Netherlands. When looking at the total yearly discharge from the combined sewer and the treatment plant, it is shown that infiltration is more effective than detention. The third study...... 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...

  9. Stormwater Drainage Manual 2008

    OpenAIRE

    Burke, Christopher B.; Burke, Thomas T.

    2008-01-01

    This manual is a comprehensive catalog of procedures, design methods and criteria, and general background information which will enable the designer to quickly learn or review the basic principles of storm drainage design. Subjects included are precipitation and hydrological cycle, runoff and its estimation, open channels, flow in gutters and inlets, stormwater storage, storm sewer system design, computer applications for computing watershed runoff, and water quality. Included in the appendic...

  10. Rain Gardens: Stormwater Infiltrating Systems

    Science.gov (United States)

    The hydrological dynamics and changes in stormwater nutrient concentrations within rain gardens were studied by introducing captured stormwater runoff to rain gardens at EPA’s Urban Water Research Facility in Edison, New Jersey. The runoff used in these experiments was collected...

  11. Impacts of Changing Climate, Hydrology and Land Use on the Stormwater Runoff of Urbanizing Central Florida

    Science.gov (United States)

    Huq, E.; Abdul-Aziz, O. I.

    2017-12-01

    We computed the historical and future storm runoff scenarios for the Shingle Creek Basin, including the growing urban centers of central Florida (e.g., City of Orlando). Storm Water Management Model (SWMM 5.1) of US EPA was used to develop a mechanistic hydrologic model for the basin by incorporating components of urban hydrology, hydroclimatological variables, and land use/cover features. The model was calibrated and validated with historical streamflow of 2004-2013 near the outlet of the Shingle Creek. The calibrated model was used to compute the sensitivities of stormwater budget to reference changes in hydroclimatological variables (rainfall and evapotranspiration) and land use/cover features (imperviousness, roughness). Basin stormwater budgets for the historical (2010s = 2004-2013) and future periods (2050s = 2030-2059; 2080s = 2070-2099) were also computed based on downscaled climatic projections of 20 GCMs-RCMs representing the coupled model intercomparison project (CMIP5), and anticipated changes in land use/cover. The sensitivity analyses indicated the dominant drivers of urban runoff in the basin. Comparative assessment of the historical and future stormwater runoff scenarios helped to locate basin areas that would be at a higher risk of future stormwater flooding. Importance of the study lies in providing valuable guidelines for managing stormwater flooding in central Florida and similar growing urban centers around the world.

  12. Pollution from Urban Stormwater Infiltration

    DEFF Research Database (Denmark)

    Mikkelsen, Peter Steen; Weyer, G.; Berry, C.

    1994-01-01

    Stormwater infiltration in urban areas gives cause for concern with regard to the risk of soil and groundwater pollution. Compared with conventional storm drainage, infiltration introduces different and widely unknown conditions governing the impacts and the fate of the pollutants......, and it is therefore difficult to assess the overall environmental impact. This paper gives a state of the art assessment of the water quality aspects of stormwater infiltration and proposes ways of managing the inherent problems. The major stormwater pollution sources are highlighted and the different processes...

  13. Stormwater TMDL Implementation Support Manual

    Science.gov (United States)

    The objective of this document is to provide support to stakeholders, who will be implementing the TMDLs, in identifying and taking actions to reduce, and ultimately fix, stormwater impairments in water bodies.

  14. Stormwater management at the ARID INEL

    International Nuclear Information System (INIS)

    Walker, E.D.

    1994-01-01

    NPDES stormwater permits are required for stormwater discharges to waters of the US (WUS). The Idaho National Engineering Laboratory (INEL) applied for coverage under a general NPDES stormwater permit because there is some potential for stormwater discharge to the Big Lost River System, which could infiltrate to groundwater. The main requirements of the permit are to prevent contaminants from coming into contact with stormwater and prevent contaminated stormwater from running off of facilities into WUS or groundwater. All INEL major facility areas have prepared and implemented stormwater pollution prevention plans (SWPPPs). The INEL also applied for coverage under a separate NPDES general permit for stormwater discharges from construction sites. An INEL Generic SWPPP for construction activities was prepared and implemented for all construction projects at the INEL

  15. Stormwater quality characteristics in (Dutch) urban areas

    NARCIS (Netherlands)

    Nick van de Giesen; Frans van de Ven; ir. Floris Boogaard; Jeroen G. Langeveld

    2014-01-01

    Stormwaters, flowing into storm sewers, are known to significantly increase the annual pollutant loads entering urban receiving waters and this results in significant degradation of the receiving water quality. Knowledge of the characteristics of stormwater pollution enables urban planners to

  16. Urban Stormwater Characterization, Control, and Treatment.

    Science.gov (United States)

    Moore, Trisha L; Rodak, Carolyn M; Vogel, Jason R

    2017-10-01

    A summary of 246 studies published in 2016 on topics related to the characterization and management of urban stormwater runoff is presented in the following review. The review is structured along three major topical areas: (1) general characterization of stormwater quantity and quality; (2) engineered systems for stormwater control and treatment, including erosion and sediment control practices, constructed stormwater ponds and wetlands, bioretention, permeable pavement, greenroofs, and rainwater harvesting and (3) watershedscale application of stormwater treatment and control practices. Common research themes and needs highlighted throughout this review include efforts to better understand stormwater transport and treatment mechanisms and their representation in models, advancements to optimize the design of stormwater control measures to meet specific hydrologic and/or water quality targets, and increasing understanding of the biophysical and social factors that influence watershed-scale implementation of low impact development and other stormwater control measures.

  17. Science in Action: National Stormwater Calculator (SWC) ...

    Science.gov (United States)

    Stormwater discharges continue to cause impairment of our Nation’s waterbodies. Regulations that require the retention and/or treatment of frequent, small storms that dominate runoff volumes and pollutant loads are becoming more common. EPA has developed the National Stormwater Calculator (SWC) to help support local, state, and national stormwater management objectives to reduce runoff through infiltration and retention using green infrastructure practices as low impact development (LID) controls. To inform the public on what the Stormwater Calculator is used for.

  18. Pollution from Urban Stormwater Infiltration

    DEFF Research Database (Denmark)

    Mikkelsen, Peter Steen; Weyer, G.; Berry, C.

    1994-01-01

    Stormwater infiltration in urban areas gives cause for concern with regard to the risk of soil and groundwater pollution. Compared with conventional storm drainage, infiltration introduces different and widely unknown conditions governing the impacts and the fate of the pollutants, and it is ther......Stormwater infiltration in urban areas gives cause for concern with regard to the risk of soil and groundwater pollution. Compared with conventional storm drainage, infiltration introduces different and widely unknown conditions governing the impacts and the fate of the pollutants......, and it is therefore difficult to assess the overall environmental impact. This paper gives a state of the art assessment of the water quality aspects of stormwater infiltration and proposes ways of managing the inherent problems. The major stormwater pollution sources are highlighted and the different processes...... operating in the soil and groundwater are described. The paper also discusses how the environmental risk of urban stormwater infiltration can be assessed, and outlines the possibilities for designing environmentally safe infiltration systems....

  19. Best management practices for nutrient and sediment retention in urban stormwater runoff.

    Science.gov (United States)

    Hogan, Dianna M; Walbridge, Mark R

    2007-01-01

    Stormwater management infrastructure is utilized in urban areas to alleviate flooding caused by decreased landscape permeability from increased impervious surface cover (ISC) construction. In this study, we examined two types of stormwater detention basins, SDB-BMPs (stormwater detention basin-best management practice), and SDB-FCs (stormwater detention basin-flood control). Both are constructed to retain peak stormwater flows for flood mitigation. However, the SDB-BMPs are also designed using basin topography and wetland vegetation to provide water quality improvement (nutrient and sediment removal and retention). The objective of this study was to compare SDB (both SDB-BMP and SDB-FC) surface soil P concentrations, P saturation, and Fe chemistry with natural riparian wetlands (RWs), using sites in Fairfax County, Virginia as a model system. The SDB-BMPs had significantly greater surface soil total P (P(t)) concentrations than the RWs and SDB-FCs (831.9 +/- 32.5 kg ha(-1), 643.3 +/- 19.1 kg ha(-1), and 652.1 +/- 18.8 kg ha(-1), respectively). The soil P sorption capacities of SDB-BMPs were similar to the RWs, and were greater than those of SDB-FCs, appearing to result in greater soil P removal and retention in SDB-BMPs compared with SDB-FCs. Increased Fe concentrations and relatively greater amounts of more crystalline forms of Fe in SDB-BMP soils suggested increased sediment deposition compared with RW and SDB-FC soils. Data suggest that SDB nutrient and sediment retention is facilitated in SDB-BMPs. When stormwater management is necessary, use of SDB-BMPs instead of SDB-FCs could foster more responsible urban development and be an appropriate mitigation action for receiving aquatic ecosystems.

  20. Photodegradation of three stormwater biocides

    DEFF Research Database (Denmark)

    Minelgaite, Greta; Nielsen, Asbjørn Haaning; Pedersen, Morten Lauge

    2017-01-01

    Photodegradation of carbendazim, diuron and terbutryn was investigated at controlled laboratory conditions under UV light and under natural sunlight. Demineralized water and two different waters from stormwater retention ponds were used. An observed decline in biocide concentration was related...... to the accumulated light energy during the degradation time. Diuron and terbutryn were degradable under UV light following 1st order degradation kinetics, while no significant decrease of carbendazim was observed throughout the duration of experiments. Photodegradation of diuron and terbutryn was slightly faster...... indicates that photodegradation is not a major process contributing to the removal of carbendazim, diuron and terbutryn in stormwater retention ponds....

  1. Green Roofs for Stormwater Management

    Science.gov (United States)

    This project evaluated green roofs as a stormwater management tool. Results indicate that the green roofs are capable of removing 40% of the annual rainfall volume from a roof through retention and evapotranspiration. Rainfall not retained by green roofs is detained, effectively...

  2. 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

  3. Best practices for quality management of stormwater pipe construction : [summary].

    Science.gov (United States)

    2014-02-01

    Although largely unseen, stormwater pipe : systems are integral and important features : of the transportation network. Stormwater : systems support the safety and integrity of : roadways by directing stormwater away from : roadway structures to disc...

  4. The role of trees in urban stormwater management

    Science.gov (United States)

    Urban impervious surfaces convert precipitation to stormwater runoff, which causes water quality and quantity problems. While traditional stormwater management has relied on gray infrastructure such as piped conveyances to collect and convey stormwater to wastewater treatment fac...

  5. Chapter 5: Quality assurance/quality control in stormwater sampling

    Science.gov (United States)

    Sampling the quality of stormwater presents unique challenges because stormwater flow is relatively short-lived with drastic variability. Furthermore, storm events often occur with little advance warning, outside conventional work hours, and under adverse weather conditions. Therefore, most stormwat...

  6. 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...

  7. Stormwater-runoff data for a highway area, Broward County, Florida

    Science.gov (United States)

    Hardee, Jack; Miller, Robert A.; Mattraw, H.C.

    1978-01-01

    Rainfall, stormwater runoff, and water-quality data are summarized for a highway area near Pompano Beach, Florida. Loads for 21 water-quality constituents were computed for the runoff from 45 storm events between April 1975 and July 1977. The size of the basin is 58.3 acres and 36 percent impervious. Stormwater runoff from urban watersheds represent an unqualified but possibly major source of contaminants to the numerous canals in south Florida. The quantification of the contaminate load from different land-use areas will assist governmental agencies involved with pollution control in evaluating alternative drainage system designs. (Woodard-USGS)

  8. NATIONAL STORMWATER CALCULATOR: LOW IMPACT DEVELOPMENT STORMWATER CONTROL COST ESTIMATION PROGRAMMING & FUTURE ENHANCEMENTS

    Science.gov (United States)

    National Stormwater Calculator: Low Impact Development Stormwater Control Cost Estimation Programming & Future EnhancementsJason Berner1; Michael Tryby1; Scott Struck2, Dan Pankani2, Marion Deerhake3, Michelle Simon11. USEPA2. GeoSyntec, Inc.3. RTI, Inc.The National Stormwater Ca...

  9. 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...

  10. Catchment-scale hydrologic implications of parcel-level stormwater management (Ohio USA)

    Science.gov (United States)

    Shuster, William; Rhea, Lee

    2013-04-01

    SummaryThe effectiveness of stormwater management strategies is a key issue affecting decision making on urban water resources management, and so proper monitoring and analysis of pilot studies must be addressed before drawing conclusions. We performed a pilot study in the suburban Shepherd Creek watershed located in Cincinnati, Ohio to evaluate the practicality of voluntary incentives for stormwater quantity reduction on privately owned suburban properties. Stream discharge and precipitation were monitored 3 years before and after implementation of the stormwater management treatments. To implement stormwater control measures, we elicited the participation of citizen landowners with two successive reverse-auctions. Auctions were held in spring 2007, and 2008, resulting in the installation of 85 rain gardens and 174 rain barrels. We demonstrated an analytic process of increasing model flexibility to determine hydrologic effectiveness of stormwater management at the sub-catchment level. A significant albeit small proportion of total variance was explained by both the effects of study period (˜69%) and treatment-vs.-control (˜7%). Precipitation-discharge relationships were synthesized in estimated unit hydrographs, which were decomposed and components tested for influence of treatments. Analysis of unit hydrograph parameters showed a weakened correlation between precipitation and discharge, and support the output from the initial model that parcel-level green infrastructure added detention capacity to treatment basins. We conclude that retrofit management of stormwater runoff quantity with green infrastructure in a small suburban catchment can be successfully initiated with novel economic incentive programs, and that these measures can impart a small, but statistically significant decrease in otherwise uncontrolled runoff volume. Given consistent monitoring data and analysis, water resource managers can use our approach as a way to estimate actual effectiveness of

  11. Assessment of retention basin volume and outlet capacity in urban ...

    Indian Academy of Sciences (India)

    - trol of pollution moved by rainfall runoff is achieved by installing outlets and small retention basins in stormwater collection systems, thereby allowing only a certain amount of rainfall water to overflow and leading the remaining to treatment ...

  12. Annual Report: 2010-2011 Storm Season Sampling For NON-DRY DOCK STORMWATER MONITORING FOR PUGET SOUND NAVAL SHIPYARD, BREMERTON, WA

    Energy Technology Data Exchange (ETDEWEB)

    Brandenberger, Jill M.; Metallo, David; Johnston, Robert K.; Gebhardt, Christine; Hsu, Larry

    2012-09-01

    This interim report summarizes the stormwater monitoring conducted for non-dry dock outfalls in both the confined industrial area and the residential areas of Naval Base Kitsap within the Puget Sound Naval Shipyard (referred to as the Shipyard). This includes the collection, analyses, and descriptive statistics for stormwater sampling conducted from November 2010 through April 2011. Seven stormwater basins within the Shipyard were sampled during at least three storm events to characterize non-dry dock stormwater discharges at selected stormwater drains located within the facility. This serves as the Phase I component of the project and Phase II is planned for the 2011-2012 storm season. These data will assist the Navy, USEPA, Ecology and other stakeholders in understanding the nature and condition of stormwater discharges from the Shipyard and inform the permitting process for new outfall discharges. The data from Phase I was compiled with current stormwater data available from the Shipyard, Sinclair/Dyes Inlet watershed, and Puget Sound in order to support technical investigations for the Draft NPDES permit. The permit would require storm event sampling at selected stormwater drains located within the Shipyard. However, the data must be considered on multiple scales to truly understand potential impairments to beneficial uses within Sinclair and Dyes Inlets.

  13. Decreasing Runoff and Increasing Stormwater Infiltration

    OpenAIRE

    Freeborn, John

    2011-01-01

    The responsibility for stormwater management is often handled on a large scale and can be fragmented between state, local, and municipal government. While the focus is typically on large developments and the storm sewers systems, each homeowner can significantly reduce the stormwater load that leaves his or her property, thereby improving surface water quality and helping to recharge groundwater reserves.

  14. Science in Action: National Stormwater Calculator (SWC)

    Science.gov (United States)

    Stormwater discharges continue to cause impairment of our Nation’s waterbodies. Regulations that require the retention and/or treatment of frequent, small storms that dominate runoff volumes and pollutant loads are becoming more common. EPA has developed the National Stormwater C...

  15. Elemental Concentrations in Urban Green Stormwater Infrastructure Soils

    Science.gov (United States)

    Michelle C. Kondo; Raghav Sharma; Alain F. Plante; Yunwen Yang; Igor Burstyn

    2016-01-01

    Green stormwater infrastructure (GSI) is designed to capture stormwater for infiltration, detention, evapotranspiration, or reuse. Soils play a key role in stormwater interception at these facilities. It is important to assess whether contamination is occurring in GSI soils because urban stormwater drainage areas often accumulate elements of concern. Soil contamination...

  16. 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.

  17. Sustainable Stormwater Management: Examining the Role of Local Planning Capacity in Mitigating Peak Surface Runoff

    Directory of Open Access Journals (Sweden)

    Hyun Woo Kim

    2016-08-01

    Full Text Available The Chesapeake Bay, the largest estuary in the United States, is rich in natural resources. Its watershed has been impacted by excessive and degraded stormwater runoff from rapid urbanization. We used an empirical approach to investigate how local planning capacity in the Chesapeake Bay watershed affected stream flow. A multiple regression analysis was employed to examine to what extent that the planning factors and other contextual variables were associated with peak runoff. Counterintuitively, we found that sub-basins included in the sample jurisdictions with a relatively high plan quality score tend to generate higher volumes of peak runoff. Results further indicate that specific geographical, basin characteristic, and biophysical factors affected mean annual peak runoff significantly. Overall, our findings highlight the importance of local planning capacity and sustainable stormwater management concepts in mitigating excessive runoff.

  18. 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.

  19. Introduction to Mental Retardation

    Science.gov (United States)

    Arc of the United States, 2004

    2004-01-01

    The purpose of this document is to define mental retardation and answer questions related to this topic. According to the American Association on Mental Retardation (AAMR), mental retardation is a disability that occurs before age 18. It is characterized by significant limitations in intellectual functioning and adaptive behaviors as expressed in…

  20. 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...

  1. An urban runoff model designed to inform stormwater management decisions.

    Science.gov (United States)

    Beck, Nicole G; Conley, Gary; Kanner, Lisa; Mathias, Margaret

    2017-05-15

    We present an urban runoff model designed for stormwater managers to quantify runoff reduction benefits of mitigation actions that has lower input data and user expertise requirements than most commonly used models. The stormwater tool to estimate load reductions (TELR) employs a semi-distributed approach, where landscape characteristics and process representation are spatially-lumped within urban catchments on the order of 100 acres (40 ha). Hydrologic computations use a set of metrics that describe a 30-year rainfall distribution, combined with well-tested algorithms for rainfall-runoff transformation and routing to generate average annual runoff estimates for each catchment. User inputs include the locations and specifications for a range of structural best management practice (BMP) types. The model was tested in a set of urban catchments within the Lake Tahoe Basin of California, USA, where modeled annual flows matched that of the observed flows within 18% relative error for 5 of the 6 catchments and had good regional performance for a suite of performance metrics. Comparisons with continuous simulation models showed an average of 3% difference from TELR predicted runoff for a range of hypothetical urban catchments. The model usually identified the dominant BMP outflow components within 5% relative error of event-based measured flow data and simulated the correct proportionality between outflow components. TELR has been implemented as a web-based platform for use by municipal stormwater managers to inform prioritization, report program benefits and meet regulatory reporting requirements (www.swtelr.com). Copyright © 2017. Published by Elsevier Ltd.

  2. Rainfall, Discharge, and Water-Quality Data During Stormwater Monitoring, July 1, 2007, to June 30, 2008; Halawa Stream Drainage Basin and the H-1 Storm Drain, Oahu, Hawaii

    Science.gov (United States)

    Presley, Todd K.; Jamison, Marcael T.J.; Young, Stacie T.M.

    2008-01-01

    Storm runoff water-quality samples were collected as part of the State of Hawaii Department of Transportation Stormwater Monitoring Program. The program is designed to assess the effects of highway runoff and urban runoff on Halawa Stream and to assess the effects from the H-1 storm drain on Manoa Stream. For this program, rainfall data were collected at three stations, continuous discharge data at four stations, and water-quality data at six stations, which include the four continuous discharge stations. This report summarizes rainfall, discharge, and water-quality data collected between July 1, 2007, and June 30, 2008. A total of 16 environmental samples were collected over two storms during July 1, 2007, to June 30, 2008, within the Halawa Stream drainage area. Samples were analyzed for total suspended solids, total dissolved solids, nutrients, chemical oxygen demand, and selected trace metals (cadmium, chromium, copper, lead, and zinc). Additionally, grab samples were analyzed for oil and grease, total petroleum hydrocarbons, fecal coliform, and biological oxygen demand. Some samples were analyzed for only a partial list of these analytes because an insufficient volume of sample was collected by the automatic samplers. Three additional quality-assurance/quality-control samples were collected concurrently with the storm samples. A total of 16 environmental samples were collected over four storms during July 1, 2007, to June 30, 2008 at the H-1 Storm Drain. All samples at this site were collected using an automatic sampler. Samples generally were analyzed for total suspended solids, nutrients, chemical oxygen demand, oil and grease, total petroleum hydrocarbons, and selected trace metals (cadmium, chromium, copper, lead, nickel, and zinc), although some samples were analyzed for only a partial list of these analytes. During the storm of January 29, 2008, 10 discrete samples were collected. Varying constituent concentrations were detected for the samples collected

  3. Monitoring micropollutants in the Swist river basin.

    Science.gov (United States)

    Christoffels, Ekkehard; Brunsch, Andrea; Wunderlich-Pfeiffer, Jens; Mertens, Franz Michael

    2016-11-01

    Micropollutant pathways were studied for the Swist river basin (Western Germany). The aim was to verify the effectiveness of a monitoring approach to detect micropollutants entering the river. In a separate sewer system, water was frequently found to be contaminated with micropollutants. Improper connections of sewage canals to the stormwater network seemed to be the cause of pollution. Wastewater treatment plants (WWTPs) exerted the largest influence on micropollutants for the receiving river. During a flu outbreak, antibiotics in the Swist stemming from WWTPs increased remarkably. Elevated levels of pharmaceuticals were measured in discharges from a combined sewer overflow (CSO). The study showed that the pharmaceutical load of a CSO was significantly reduced by advanced treatment with a retention soil filter. Painkillers, an anticonvulsant and beta blockers were the most often detected pharmaceuticals in the sewage of urban areas. Herbicides, flame retardants and industrial compounds were also observed frequently. On cropland, Chloridazon and Terbuthylazine compounds were often found in landscape runoff. Fungicides and insecticides were the most frequent positive findings in runoff from orchards. The paper shows that a coherent approach to collecting valid information regarding micropollutants and to addressing relevant pathways as a basis for appropriate management strategies could be established.

  4. San Pablo Avenue Green Stormwater Spine

    Science.gov (United States)

    Information about the SFBWQP San Pablo Avenue Green Stormwater Spine Project project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  5. 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...

  6. Wastewater dilution index partially explains observed polybrominated diphenyl ether flame retardant concentrations in osprey eggs from Columbia River Basin, 2008-2009.

    Science.gov (United States)

    Henny, Charles J; Grove, Robert A; Kaiser, James L; Johnson, Branden L; Furl, Chad V; Letcher, Robert J

    2011-06-01

    Several polybrominated biphenyl ether (PBDE) congeners were found in all 175 osprey (Pandion haliaetus) eggs collected from the Columbia River Basin between 2002 and 2009. ΣPBDE concentrations in 2008-2009 were highest in osprey eggs from the two lowest flow rivers studied; however, each river flowed through relatively large and populous metropolitan areas (Boise, Idaho and Spokane, Washington). We used the volume of Wastewater Treatment Plant (WWTP) discharge, a known source of PBDEs, as a measure of human activity at a location, and combined with river flow (both converted to millions of gallons/day) created a novel approach (an approximate Dilution Index) to relate waterborne contaminants to levels of these contaminants that reach avian eggs. This approach provided a useful understanding of the spatial osprey egg concentration patterns observed. Individual osprey egg concentrations along the Upper Willamette River co-varied with the Dilution Index, while combined egg data (geometric means) from rivers or segments of rivers showed a strong, significant relationship to the Dilution Index with one exception, the Boise River. There, we believe osprey egg concentrations were lower than expected because Boise River ospreys foraged perhaps 50-75% of the time off the river at ponds and lakes stocked with fish that contained relatively low ΣPBDE concentrations. Our limited temporal data at specific localities (2004-2009) suggests that ΣPBDE concentrations in osprey eggs peaked between 2005 and 2007, and then decreased, perhaps in response to penta- and octa-PBDE technical mixtures no longer being used in the USA after 2004. Empirical estimates of biomagnification factors (BMFs) from fish to osprey eggs were 3.76-7.52 on a wet weight (ww) basis or 4.37-11.0 lipid weight. Our earlier osprey study suggested that ΣPBDE egg concentrations >1,000 ng/g ww may reduce osprey reproductive success. Only two of the study areas sampled in 2008-2009 contained individual eggs with

  7. Toward city-scale water quality control: building a theory for smart stormwater systems

    Science.gov (United States)

    Kerkez, B.; Mullapudi, A. M.; Wong, B. P.

    2016-12-01

    Urban stormwater systems are rarely designed as actual systems. Rather, it is often assumed that individual Best Management Practices (BMPs) will add up to achieve desired watershed outcomes. Given the rise of BMPs and green infrastructure, we ask: does doing "best" at the local scale guarantee the "best" at the global scale? Existing studies suggest that the system-level performance of distributed stormwater practices may actually adversely impact watersheds by increasing downstream erosion and reducing water quality. Optimizing spatial placement may not be sufficient, however, since precipitation variability and other sources of uncertainty can drive the overall system into undesirable states. To that end, it is also important to control the temporal behavior of the system, which can be achieved by equipping stormwater elements (ponds, wetlands, basins, bioswales, etc.) with "smart" sensors and valves. Rather than building new infrastructure, this permits for existing assets to be repurposed and controlled to adapt to individual storm events. While we have learned how to build and deploy the necessary sensing and control technologies, we do not have a framework or theory that combines our knowledge of hydrology, hydraulics, water quality and control. We discuss the development of such a framework and investigate how existing water domain knowledge can be transferred into a system-theoretic context to enable real-time, city-scale stormwater control. We apply this framework to water quality control in an urban watershed in southeast Michigan, which has been heavily instrumented and retrofitted for control over the past year.

  8. The Evaluation of Stormwater Runoff

    Directory of Open Access Journals (Sweden)

    Vaidas Vinciūnas

    2011-12-01

    Full Text Available Conventional wastewater flow measurement techniques are difficult to apply for stormwater runoff. Therefore, a strong need for the new types of flow measurements is foreseen, especially in the existing urban areas. Water level was measured applying a hydrostatic level meter and flow was calculated according to typical hydraulic relationship. The theoretical flow rate was calculated based on rain gauge data from the nearest metrological station. Following gauge data, the calculated storm water runoff was almost two times higher than the measured one. Differences in flow data will lead to uncertainties in statistical reports and misunderstanding between different authorities. The measurements of storm water flows are necessary, because they are associated with emission accounts, taxes on pollution and improvements to environmental quality.Article in Lithuanian

  9. Rainfall, Discharge, and Water-Quality Data During Stormwater Monitoring, July 1, 2008, to June 30, 2009 - Halawa Stream Drainage Basin and the H-1 Storm Drain, Oahu, Hawaii

    Science.gov (United States)

    Presley, Todd K.; Jamison, Marcael T.J.

    2009-01-01

    Storm runoff water-quality samples were collected as part of the State of Hawaii Department of Transportation Stormwater Monitoring Program. The program is designed to assess the effects of highway runoff and urban runoff on Halawa Stream, and to assess the effects from the H-1 storm drain on Manoa Stream. For this program, rainfall data were collected at three stations, continuous discharge data at five stations, and water-quality data at six stations, which include the five continuous discharge stations. This report summarizes rainfall, discharge, and water-quality data collected between July 1, 2008, and June 30, 2009. Within the Halawa Stream drainage area, three storms (October 25 and December 11, 2008, and February 3, 2009) were sampled during July 1, 2008, to June 30, 2009. A total of 43 environmental samples were collected during these three storms. During the storm of October 25, 2009, 31 samples were collected and analyzed individually for metals only. The other 12 samples from the other two storms were analyzed for some or all of the following analytes: total suspended solids, total dissolved solids, nutrients, chemical oxygen demand, and selected trace metals (cadmium, chromium, copper, lead, and zinc). Additionally, grab samples were analyzed for some or all of the following analytes: oil and grease, total petroleum hydrocarbons, fecal coliform, and biological oxygen demand. Some grab and composite samples were analyzed for only a partial list of these analytes, either because samples could not be delivered to the laboratory in a timely manner, or an insufficient volume of sample was collected by the automatic samplers. Two quality-assurance/quality-control samples were collected after cleaning automatic sampler lines to verify that the sampling lines were not contaminated. Four environmental samples were collected at the H-1 Storm Drain during July 1, 2008, to June 30, 2009. An oil and grease sample and a composite sample were collected during the

  10. 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...

  11. An exploratory study of the effects of stormwater pipeline materials on transported stormwater quality.

    Science.gov (United States)

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

    2017-07-01

    Implications of three sewer pipe materials (concrete, galvanized corrugated steel, and polyvinyl chloride (PVC)) for stormwater quality were explored in laboratory experiments, in which three types of stormwater, SW1-SW3, were circulated in 0.5 m long sewer pipe sections. SW1 and SW2 represented synthetic rainwater, without and with fine street sediment added (C TSS = 150 mg/L), respectively, and SW3 was actual stormwater with the same sediment addition as SW2. Following 20-min runs, with an equivalent distance of 500 m travelled by water particles, a number of statistically significant changes in the stormwater chemistry were observed: (i) pH of all the simulated stormwaters increased in the concrete pipe (from 7.0-7.3 to 8.1-9.3), (ii) turbidity decreased in two stormwaters with sediments (SW2 and SW3) in concrete and galvanized corrugated steel pipes (by 50 and 85%, respectively), (iii) the type of stormwater affected the observed copper (Cu) concentrations, with Cu diss concentrations as high as 25.3 μg/L noted in SW3 passing through the PVC pipe, and (iv) zinc (Zn) concentrations sharply increased (Zn tot = 759-1,406 μg/L, Zn diss = 670-1,400 μg/L) due to Zn elution from the galvanized steel pipe by all three stormwaters. Such levels exceeded the applicable environmental guidelines.

  12. 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.

  13. Best practices for quality management of stormwater pipe construction.

    Science.gov (United States)

    2014-02-01

    Stormwater pipe systems are integral features of transportation construction projects. Pipe culverts : direct stormwater away from roadway structures and towards designated discharge areas. The improper : installation of a pipe culvert can result in ...

  14. Enhancing nitrogen removal in stormwater treatment facilities for transportation.

    Science.gov (United States)

    2015-01-01

    Stormwater from roadways is a point source of pollution. State DOTs must comply with Total Maximum : Daily Load (TMDL) regulations for nutrients such as nitrogen, which causes water quality impairment. Existing stormwater treatment technologies, such...

  15. Key issues for sustainable urban stormwater management.

    Science.gov (United States)

    Barbosa, A E; Fernandes, J N; David, L M

    2012-12-15

    Since ancient times, it is understood that stormwater from constructed areas should be managed somehow. Waste and pollution transported by stormwater poses quantity and quality problems, affecting public health and the quality of the environment. Sanitation infrastructures in urbanized regions have different development levels and the perception of stormwater changed considerably during the centuries and especially in recent years. Still, there is an evident worldwide heterogeneity when analyzing the lack of studies on urban stormwater conducted in some Asian or African countries. Strategies for sustainable stormwater management are needed at different decision levels (political, regional or local scale, for instance) but all of them need information and a clear understanding of the possibilities that are at stake as well as the main consequences of each decision. A sound approach to stormwater management should be flexible, based on local characteristics, and should take into consideration temporal, spatial and administrative factors and law, among other issues. Economic or technical constraints define different decision scenarios. Best Management Practices should be seen as an opportunity for development and improvement of social, educational and environmental conditions in urbanized and surrounding areas. Therefore they require an ample perspective and the participation of different stakeholders. High-quality decision needs time and a fair overview of the problem: the purpose of this document is to contribute to sustainable stormwater management, informing on the most relevant factors that should be assessed and their interaction. A flowchart has been produced and is presented, indicating the most relevant steps, processes and information that should be taken into account in urban development. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Stormwater quality modeling for upscaling MSMA stormwater management ecohydrology

    Science.gov (United States)

    Sidek, L. M.; Zainal Abidin, M. R.; Esfahani, F. Z.; Basri, H.

    2013-06-01

    Langat River is 180 km length has a total catchment area of 2,350 km2. The Langat River is classified as Class II in the upstream, and as the water flows downstream the quality degrades to Class III and IV. This degradation is caused by the rapid and uncontrolled urbanization in the contributing catchment of the river. The characteristics of the river and its contributing catchment are modeled using Model for Urban Stormwater Improvement Conceptualisation (MUSIC) in order to rehabilitate the river and enhance its Water Quality Index (WQI) to Class II. The historical rainfall data was obtained from DID for the period from 1974 to 2012. This paper presents the effects of various BMP Components on rehabilitating the water quality of the river. In addition, the minimum amount of river flow required for protection of the habitats and the river's ecology has been assessed during the dry seasons. The outcomes of this study suggest the most appropriate Best Management Practices that can be used as solutions for the river's rehabilitation. Simulations and modeling result found out that a configuration of wetlands, bio-retention systems and ponds are capable to reduce pollutants loadings such as TSS, TP and TN by 85.1%, 69.1% and 37.5% respectively

  17. Centralised urban stormwater harvesting for potable reuse.

    Science.gov (United States)

    McArdle, P; Gleeson, J; Hammond, T; Heslop, E; Holden, R; Kuczera, G

    2011-01-01

    Urban impervious areas provide a guaranteed source of runoff, especially in cities with high rainfall - this represents a source of water with low sensitivity to unfavourable climate change. Whilst the potential to reuse stormwater has long been recognised, its quality has largely limited usage to non-potable applications requiring the use of a third-pipe network, a prohibitively expensive option in established urban areas. Given recent advances in membrane filtration, this study investigates the potential of harvesting and treating stormwater to a potable standard to enable use of the potable distribution network. A case study based on the Throsby Creek catchment in Newcastle explores the issue. The high seasonally uniform rainfall provides insight into the maximum potential of such an option. Multicriterion optimisation was used to identify Pareto optimal solutions for harvesting, storing and treating stormwater. It is shown that harvesting and treating stormwater from a 13 km² catchment can produce yields ranging from 8.5 to 14.2 ML/day at costs ranging from AU$2.60/kL to AU$2.89/kL, which may become viable as the cost of traditional supply continues to grow. However, there are significant social impacts to deal with including alienation of public land for storage and community acceptance of treated stormwater.

  18. Stormwater Infrastructure and other features - Linear Features

    Data.gov (United States)

    Vermont Center for Geographic Information — This data was collected and compiled for various towns in watersheds (currently including the Missisquoi Basin, Winooski Basin, Connecticut River Basin, Lamoille...

  19. Stormwater Infrastructure and other features - Point Features

    Data.gov (United States)

    Vermont Center for Geographic Information — This data was collected and compiled for various towns in watersheds (currently including the Missisquoi Basin, Winooski Basin, Connecticut River Basin, Lamoille...

  20. Stormwater Infrastructure and other features - Area Features

    Data.gov (United States)

    Vermont Center for Geographic Information — This data was collected and compiled for various towns in watersheds (currently including the Missisquoi Basin, Winooski Basin, Connecticut River Basin, Lamoille...

  1. Mental Retardation in Perspective.

    Science.gov (United States)

    Horvath, Michael; And Others

    This monograph presents a general introduction to the history, classification, and characteristics of mental retardation. It begins with a discussion of the history of mental retardation from ancient Greece and Rome to the present. The beginnings of special education are traced to the early 19th century in Europe. Major influences in treatment of…

  2. A new service offered by rural environment to the city: stormwater reception.

    Science.gov (United States)

    Chiaradia, Enrico Antonio; Weber, Enrico; Masseroni, Daniele; Battista Bischetti, Gian; Gandolfi, Claudio

    2017-04-01

    Stormwaters are the main cause of urban floods in many urbanized areas. Historically, stormwater management practices have been focused on building infrastructures that achieve runoff attenuation through the storage of water volumes in large detention basins. However, this approach has proven to be insufficient to resolve the problem as well as it is difficult to implement in areas with a dense urban fabric. Nowadays, around the world, water managers are increasingly embracing "soft path" approaches, that aim to manage the excess of urban runoff through Green Infrastructures, where detention capacities are provided by the retention proprieties of soil and vegetation elements. Along the line of these new sustainable stormwater management practices, the aim of this study is to promote a further paradigm-shift with respect to the traditional practices i.e. to investigate the possibility to use the already existing green infrastructures of the peri-urban rural areas as reception element of the surplus of urban runoff. Many territories in Northern Italy, for example. are characterized by a high density of irrigation canals and agricultural fields that, in some cases, are isolated or pent-up inside urbanized areas. Both these elements may represent storage volumes for accumulating stormwater from urban areas. In this work, we implemented a holistic framework, based on Self Organized Map technique (SOM), with the objective to produce a spatial map of the stormwater reception level that can be provided by the rural environment. We elaborated physiographic characteristics of irrigation canals and agricultural fields through the SOM algorithm obtaining as output a series of cluster groups with the same level of receptivity. This procedure was applied on an area of 1933 km2 around the city of Milan and a map of 250x250m resolution was obtained with three different levels of stormwater reception capacity. About 50% of rural environment has a good level of reception and only 30

  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. Detection of Human Sewage in Urban Stormwater Using DNA Based Methods and Stable Isotope Analysis

    Science.gov (United States)

    McLellan, S. L.; Malet, N.; Sauer, E.; Mueller-Spitz, S.; Borchardt, M.

    2008-12-01

    Urban stormwater is a major source of fecal indicator bacteria in the Milwaukee River Basin, a major watershed draining to Lake Michigan. Much of the watershed is in highly urbanized areas and Escherichia coli (E. coli) levels have been found to be 20,000 CFU per 100 ml in the estuary leading to Lake Michigan. Aging infrastructure and illicit cross connections may allow sewage to infiltrate the stormwater system and could contribute both fecal indicator bacteria and human pathogens to these waters. We conducted extensive sampling of stormwater outfalls in the lower reaches of three major tributaries. Three outfalls along the heavily urbanized Kinnickinnick (KK) were found to have geometric mean E. coli and enterococci levels of 16,200 and 28,700 CFU/100 ml, respectively. Four outfalls along the Menomonee River, draining both suburban and urban areas, had geometric mean E. coli and enterococci levels of 14,700 and 12,800 CFU/100 ml, respectively. These seven outfalls had more than 60% of the samples positive for human specific Bacteroides genetic marker (n=46), suggesting the presence of human sources. In addition, two outfalls on Lincoln Creek, a smaller tributary of the Milwaukee River, had geometric mean E. coli and enterococci levels of 16,700 and 14,900 CFU per 100 ml, respectively. The human specific Bacteroides marker was positive in nearly 90% of the samples (n=24). Subsequent virus testing at one of these outfalls confirmed human pathogens were present with adenovirus detected at 1.3 x 10E3 genomic equivalents (ge)/L, enterovirus at 1.9 x 10E4 ge/L and G1 norovirus at 1.5 x 10E3 ge/L; these values are similar to concentrations found in sewage. Stable isotope studies were conducted in the three tributaries to investigate the relationship between delta C and delta N isotopic composition and microbiological quality of this urban freshwater system. This work is based on the premise that the organic matter of the stormwater will have a stable isotopic signature

  5. Fire retardant formulations

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to compositions where a substrate is liable to catch fire such as bituminous products, paints, carpets or the like. The invention relates to a composition comprising 40-95 weight % of a substrate to be rendered fire resistant such as bituminous material or paint......, carpets which substrate is mixed with 5-60 weight % of a fire retardant component. The invention relates to a fire retardant component comprising or being constituted of attapulgite, and a salt being a source of a blowing or expanding agent, where the attapulgite and the salt are electrostatically...... connected by mixing and subjecting the mixture of the two components to agitation. Also, the invention relates to compositions comprising 40-95 weight % of a substrate to be rendered fire resistant mixed with 5-60 weight % of a fire retardant according to claim 1 or 2, which fire retardant component...

  6. Functional nanostructured materials for stormwater runoff treatment

    DEFF Research Database (Denmark)

    Ko, Dongah

    Numerous heavy metal removal practices for stormwater runoff have been studied and applied; however, there is still room for improvement. Among these practices, adsorption has proven to be the most efficient way of removing heavy metals. Commonly used adsorbents have an innate sorption capacity i...

  7. Street tree structural differences and associated stormwater ...

    Science.gov (United States)

    Green infrastructure approaches leverage vegetation and soil to improve environmental quality. Municipal street trees are crucial components of urban green infrastructure because they provide stormwater interception benefits and other ecosystem services. Thus, it is important to understand the patterns and drivers of structural heterogeneity in urban street tree assemblages. In this study, we compared the forest structure of street trees across nine communities along both geographic and demographic gradients in metropolitan Cincinnati, Ohio, USA. Specifically, we used a two-part statistical model to compare both the proportion of sampled street segments containing zero trees, and basal area magnitude for street segments with trees. We made community-scale comparisons based on street tree management, socioeconomics, and geographic setting. Then, using modeled stormwater interception estimates from i-Tree Streets, we investigated the implications of heterogeneity in street tree assemblages for stormwater interception benefits. The forest structure of street trees varied across communities in relation to management practices, namely participation in the Tree City USA program. As a consequence of this structural difference, we observed a stark discrepancy in estimated stormwater interception between Tree City USA participants (128.7 m3/km street length) and non-participants (59.2 m3/km street length). While street tree assemblages did not vary by community poverty s

  8. Sustainability assessment of stormwater management systems

    DEFF Research Database (Denmark)

    Brudler, Sarah; Arnbjerg-Nielsen, Karsten; Ammitsøe, Christian

    We quantify ecotoxicity impacts caused by different solutions to manage stormwater using life cycle assessment. As a novelty, we include emissions of a wide range of pollutants present in runoff. These emissions turn out to be of great importance, especially in decentralized, above surface systems....

  9. Green Retrofits to Bring Jobs, Stormwater Controls

    Science.gov (United States)

    Community-based public-private partnership fostered by EPA’s Mid-Atlantic Water Protection Division is underway in Prince George’s County, Maryland, to generate “faster, cheaper, greener” controls for stormwater and benefit the local economy and community.

  10. 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...

  11. Radiation and mental retardation

    International Nuclear Information System (INIS)

    Pochin, E.E.

    1988-01-01

    A brief article discusses mental retardation in children who had been exposed to ionizing radiation in utero. The time of greatest sensitivity is between the 8th and 15th week after conception and the time of lesser sensitivity between the 16th and 25th weeks. An examination of the thresholds for exposure indicate that severe mental retardation would not result from any present environmental exposures of the public. (U.K.)

  12. Stormwater Controls for Pollutant Removal on GDOT Right-Of-Way

    Science.gov (United States)

    2012-04-11

    The Georgia Department of Transportation (GDOT) operates a large number of roadside stormwater treatment facilities to contain and treat roadside stormwater runoff. The stormwater best management practices (BMPs) were designed with an emphasis on the...

  13. Assessment of direct exposure and leaching risk from PAHs in roadway and stormwater system residuals.

    Science.gov (United States)

    Azah, Edmund; Kim, Hwidong; Townsend, Timothy

    2017-12-31

    Wastes generated from municipal cleaning activities such as street sweeping, ditch cleaning, stormwater pond maintenance, and catch basin sediment removal require appropriate management. Beneficial use of these types of waste is a good alternative to landfilling; however, there are genuine concerns about possible soil and groundwater contamination by pollutants such as polycyclic aromatic hydrocarbons (PAHs). This study assessed the potential risks associated with beneficial use of roadway and stormwater system residuals collected from 14 cities across the state of Florida, USA. Total and leachable concentrations of 16 priority PAHs in the residual samples were measured and compared to appropriate risk-based regulatory threshold values. The bioaccessibility of the PAHs found in the waste streams was also determined using in vitro gastrointestinal leaching test. Of the PAHs studied, benzo [a] pyrene measured concentrations were above appropriate risk-based regulatory threshold values for soil and groundwater, while all other detected PAHs measured concentrations were below. Benzo [a] pyrene concentration (mg/kg) in street sweepings was 1.2 times higher than residential threshold values and 6 times lower than industrial threshold values. The in vitro study found PAH bioaccessibility to range from 1.7% to 49% in six roadway and stormwater system residual samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Legacies in urban stormwater management and the effect on gully formation in a Piedmont region of the US Mid Atlantic

    Science.gov (United States)

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

    2013-12-01

    Impervious surfaces in urban areas lead to increased stormwater runoff and produce flashier hydrology which can lead to stream bank erosion and increased sediment delivery to downstream ecosystems. Since the early 1990s the EPA has enforced stormwater regulation and nowadays, practices must be implemented that minimize water quality impacts. However, legacies of stormwater management in pre-regulated areas could be an important factor in the degradation of water quality. From a larger watershed perspective there is therefore a disconnect between investments in newly developed areas where water quality deterioration is perhaps minor vs. minimal investments in pre-regulation areas where water quality deterioration is perhaps major. In this study we examine such legacies in urban stormwater management and the effect on gully formation, with the objective to identify hotspots of water quality degradation and optimal locations for reducing water quality impacts. Our research primarily focuses on older developments (pre-1990s) in the Piedmont region of the Christina River basin (CRB), a tributary of the Delaware River. Many of the streams in the CRB have impaired water quality. We used a combination of methodological approaches, including historical surveys (aerial imagery, land-use maps, stormwater design reports), field observations (WQ sampling, topographic surveys), hydrological modeling, and geospatial analysis. We developed a simple GIS-based model that predicts susceptibility for gully erosion. The model calculates runoff (using Curve Number method), performs hydrologic routing, and based on topographic indices it estimates gully susceptibility for stream reaches draining urban developments. Our results show that the gully susceptibility model produces accurate predictions, including the location of deeply incised gullies. Through geospatial analysis we also identify benefits of structural stormwater control measures and BMPs, and the role of spatial variable land

  15. Advanced instrumentation for the collection, retrieval, and processing of urban stormwater data

    Science.gov (United States)

    Robinson, Jerald B.; Bales, Jerad D.; Young, Wendi S.; ,

    1995-01-01

    The U.S. Geological Survey, in cooperation with the City of Charlotte and Mecklenburg County, North Carolina, has developed a data-collection network that uses advanced instrumentation to automatically collect, retrieve, and process urban stormwater data. Precipitation measurement and water-quality networks provide data for (1) planned watershed simulation models, (2) early warning of possible flooding, (3) computation of material export, and (4) characterization of water quality in relation to basin conditions. Advantages of advanced instrumentation include remote access to real-time data, reduced demands on and more efficient use of limited human resources, and direct importation of data into a geographical information system for display and graphic analysis.

  16. Quality of Wisconsin stormwater, 1989-94

    Science.gov (United States)

    Bannerman, Roger T.; Legg, Andrew D.; Greb, Steven R.

    1996-01-01

    Water-quality data were compiled from four urban stormwater monitoring projects conducted in Wisconsin between 1989 and 1994. These projects included monitoring in both storm-sewer pipes and urban streams. A total of 147 constitu ents were analyzed for in stormwater sampled from 10 storm-sewer pipes and four urban streams. Land uses represented by the storm-sewer watersheds included residential, commercial, industrial, and mixed. For about one-half the con stituents, at least 10 percent of the event mean con centrations exceeded the laboratory's minimum reporting limit. Detection frequencies were greater than 75 percent for many of the heavy metals and polycyclic aromatic hydrocarbons in both the storm sewer and stream samples, whereas detec tion frequencies were about 20 percent or greater for many of the pesticides in both types of sam ples. Stormwater concentrations for conventional constituents, such as suspended solids, chloride, total phosphorus, and fecal coliform bacteria were greater than minimum reporting limits almost 100 percent of the time. Concentrations of many of the constituents were high enough to say that stormwater in the storm sewers and urban streams might be contrib uting to the degradation of the streams. In this report, constituents defined as potential contami nants are those for which the laboratory minimum report limit was exceeded for at least 10 percent of the sampled storm events, and for which at least one event mean concentration exceeded an estab lished water-quality standard. Storm-sewer sam ples had event mean concentrations of lead, copper, zinc, cadmium, and silver that frequently exceeded Wisconsin's acute toxicity criteria for cold water fisheries. Wisconsin's human cancer criteria was exceeded almost 100 percent of the time for polycyclic aromatic hydrocarbons in stormwater samples from storm sewers and streams. Maximum concentrations of diazinon found in storm sewers exceeded recommended levels of diazinon. Storm

  17. Optimizing stormwater treatment practices a handbook of assessment and maintenance

    CERN Document Server

    Erickson, Andrew J; Gulliver, John S

    2013-01-01

    Optimizing Stormwater Treatment Practices: A Handbook of Assessment and Maintenance provides the information necessary for developing and operating an effective maintenance program for stormwater treatment. The book offers instructions on how to measure the level of performance of stormwater treatment practices directly and bases proposed maintenance schedules on actual performance and historical maintenance efforts and costs. The inspection methods, which are proven in the field and have been implemented successfully, are necessary as regulatory agencies are demanding evaluations of the performance of stormwater treatment practices. The authors have developed a three-tiered approach that offers readers a standard protocol for how to determine the effectiveness of stormwater treatment practices currently in place. This book also: Provides a standard protocol for how to determine the effectiveness of stormwater treatment practices Assists readers with identifying which assessment techniques to use for stormwa...

  18. Comment on “Suburban watershed nitrogen retention: Estimating the effectiveness of stormwater management structures” by Koch et al. (Elem Sci Anth 3:000063, July 2015

    Directory of Open Access Journals (Sweden)

    Christopher J. Walsh

    2015-12-01

    Full Text Available Abstract I reassess a recent analysis of uncertainty in estimates of nitrogen export from stormwater control measures, using structured expert judgment, which concluded that nitrogen export from a watershed in the Piedmont physiographic province of the Chesapeake Bay basin was an order of magnitude greater than from a watershed in the adjacent the Coastal Plain province. Re-analysis of expert responses suggests that hydrographic measurement error is a likely large source of uncertainty in N export from one of the watersheds. Mass-balance estimates of impervious runoff into stormwater drainage systems suggest that nitrogen export from the Coastal Plain watershed is an order of magnitude larger than estimated. This analysis highlights the importance of stormwater drainage infrastructure in driving the hydrology of streams in urban catchments by quarantining impervious runoff from watershed soils.

  19. Functional nanostructured materials for stormwater runoff treatment

    DEFF Research Database (Denmark)

    Ko, Dongah

    metal sorption behaviour. Although COP-63 has a moderate surface area, it demonstrated cadmium removal efficiency equivalent to highly porous activated carbon (AC), while it also exhibited 16 times faster sorption kinetics compared to AC, owing to high affinity towards disulphide and thiol functionality......Numerous heavy metal removal practices for stormwater runoff have been studied and applied; however, there is still room for improvement. Among these practices, adsorption has proven to be the most efficient way of removing heavy metals. Commonly used adsorbents have an innate sorption capacity...... in relation to high concentrations of heavy metal ions, but if they are to be used for stormwater runoff, high affinity with rapid sorption kinetics for low concentrations of heavy metals is necessary. Therefore, in this study, new types of functional nanostructured polymer sorbents for effective heavy metal...

  20. Research on Granular Media of Stormwater Sediments (On the Street and Stormwater Treatment Plants

    Directory of Open Access Journals (Sweden)

    Ginta Cholomskytė

    2011-04-01

    Full Text Available In water management, to reach optimal exploitation of stormwater net it is required to value particle size witch accumulate on the roads and ways. The sediments from stormwater sedimentation tanks, sediments from Kalvarijų street and from the industrial area (Greičiūno street 35 were taken. Was established particle size of sediments. Research showed that the biggest part of sediments 80% in sedimentation tank (Verkiai ir Karoliniškės compose the smallest parts, size – 0,25 mm. Sample from the road that particles size 0,25 compose only 25-35%. To reduce negative effect to the stormwater net exploitation it is recommended to implement street sweeping.Article in Lithuanian

  1. Crowd Sourcing to Improve Urban Stormwater Management

    Science.gov (United States)

    Minsker, B. S.; Band, L. E.; Heidari Haratmeh, B.; Law, N. L.; Leonard, L. N.; Rai, A.

    2017-12-01

    Over half of the world's population currently lives in urban areas, a number predicted to grow to 60 percent by 2030. Urban areas face unprecedented and growing challenges that threaten society's long-term wellbeing, including poverty; chronic health problems; widespread pollution and resource degradation; and increased natural disasters. These are "wicked" problems involving "systems of systems" that require unprecedented information sharing and collaboration across disciplines and organizational boundaries. Cities are recognizing that the increasing stream of data and information ("Big Data"), informatics, and modeling can support rapid advances on these challenges. Nonetheless, information technology solutions can only be effective in addressing these challenges through deeply human and systems perspectives. A stakeholder-driven approach ("crowd sourcing") is needed to develop urban systems that address multiple needs, such as parks that capture and treat stormwater while improving human and ecosystem health and wellbeing. We have developed informatics- and Cloud-based collaborative methods that enable crowd sourcing of green stormwater infrastructure (GSI: rain gardens, bioswales, trees, etc.) design and management. The methods use machine learning, social media data, and interactive design tools (called IDEAS-GI) to identify locations and features of GSI that perform best on a suite of objectives, including life cycle cost, stormwater volume reduction, and air pollution reduction. Insights will be presented on GI features that best meet stakeholder needs and are therefore most likely to improve human wellbeing and be well maintained.

  2. Using a Geographic Information System to Assess Site Suitability for Managed Aquifer Recharge using Stormwater Capture

    Science.gov (United States)

    Teo, E. K.; Harmon, R. E.; Beganskas, S.; Young, K. S.; Fisher, A. T.; Weir, W. B.; Lozano, S.

    2015-12-01

    We are completing a regional analysis of Santa Cruz and northern Monterey Counties, CA, to assess the conditions amenable to managed aquifer recharge using stormwater runoff. Communities and water supply agencies across CA are struggling to mitigate the ongoing drought and to develop secure and sustainable water supplies to support long-term municipal, agricultural, environmental and other needs. Enhanced storage of groundwater is an important part of this effort in many basins. This work is especially timely because of the recently enacted "Sustainable Groundwater Management Act" (SGMA), which requires the development of groundwater sustainability agencies and implementation of basin management plans in coming decades. Our analysis focuses specifically on the distributed collection of stormwater runoff, a water source that has typically been treated as a nuisance or waste, from drainages having an area on the order of 40-160 hectares. The first part of this project is a geographic information system (GIS) analysis using surface and subsurface data sets. Developing complete and accurate datasets across the study region required considerable effort to locate, assemble, co-register, patch, and reconcile information from many sources and scales. We have complete spatial coverage for surface data, but subsurface data is more limited in lateral extent. Sites that are most suitable for distributed stormwater capture supporting MAR have high soil infiltration capacity, are well-connected to an underlying aquifer with good transmissive and storage properties, and have space to receive MAR. Additional considerations include method of infiltration, slope, and land use and access. Based on initial consideration of surface data and slope, 7% of the complete study region appears to be "suitable or highly suitable" for MAR (in the top third of the rating system), but there is considerable spatial heterogeneity based on the distribution of shallow soils and bedrock geology.

  3. Using Agent-Based Modeling to Enhance System-Level Real-time Control of Urban Stormwater Systems

    Science.gov (United States)

    Rimer, S.; Mullapudi, A. M.; Kerkez, B.

    2017-12-01

    The ability to reduce combined-sewer overflow (CSO) events is an issue that challenges over 800 U.S. municipalities. When the volume of a combined sewer system or wastewater treatment plant is exceeded, untreated wastewater then overflows (a CSO event) into nearby streams, rivers, or other water bodies causing localized urban flooding and pollution. The likelihood and impact of CSO events has only exacerbated due to urbanization, population growth, climate change, aging infrastructure, and system complexity. Thus, there is an urgent need for urban areas to manage CSO events. Traditionally, mitigating CSO events has been carried out via time-intensive and expensive structural interventions such as retention basins or sewer separation, which are able to reduce CSO events, but are costly, arduous, and only provide a fixed solution to a dynamic problem. Real-time control (RTC) of urban drainage systems using sensor and actuator networks has served as an inexpensive and versatile alternative to traditional CSO intervention. In particular, retrofitting individual stormwater elements for sensing and automated active distributed control has been shown to significantly reduce the volume of discharge during CSO events, with some RTC models demonstrating a reduction upwards of 90% when compared to traditional passive systems. As more stormwater elements become retrofitted for RTC, system-level RTC across complete watersheds is an attainable possibility. However, when considering the diverse set of control needs of each of these individual stormwater elements, such system-level RTC becomes a far more complex problem. To address such diverse control needs, agent-based modeling is employed such that each individual stormwater element is treated as an autonomous agent with a diverse decision making capabilities. We present preliminary results and limitations of utilizing the agent-based modeling computational framework for the system-level control of diverse, interacting

  4. Hydrologic and Water-Quality Responses in Shallow Ground Water Receiving Stormwater Runoff and Potential Transport of Contaminants to Lake Tahoe, California and Nevada, 2005-07

    Science.gov (United States)

    Green, Jena M.; Thodal, Carl E.; Welborn, Toby L.

    2008-01-01

    Clarity of Lake Tahoe, California and Nevada has been decreasing due to inflows of sediment and nutrients associated with stormwater runoff. Detention basins are considered effective best management practices for mitigation of suspended sediment and nutrients associated with runoff, but effects of infiltrated stormwater on shallow ground water are not known. This report documents 2005-07 hydrogeologic conditions in a shallow aquifer and associated interactions between a stormwater-control system with nearby Lake Tahoe. Selected chemical qualities of stormwater, bottom sediment from a stormwater detention basin, ground water, and nearshore lake and interstitial water are characterized and coupled with results of a three-dimensional, finite-difference, mathematical model to evaluate responses of ground-water flow to stormwater-runoff accumulation in the stormwater-control system. The results of the ground-water flow model indicate mean ground-water discharge of 256 acre feet per year, contributing 27 pounds of phosphorus and 765 pounds of nitrogen to Lake Tahoe within the modeled area. Only 0.24 percent of this volume and nutrient load is attributed to stormwater infiltration from the detention basin. Settling of suspended nutrients and sediment, biological assimilation of dissolved nutrients, and sorption and detention of chemicals of potential concern in bottom sediment are the primary stormwater treatments achieved by the detention basins. Mean concentrations of unfiltered nitrogen and phosphorus in inflow stormwater samples compared to outflow samples show that 55 percent of nitrogen and 47 percent of phosphorus are trapped by the detention basin. Organic carbon, cadmium, copper, lead, mercury, nickel, phosphorus, and zinc in the uppermost 0.2 foot of bottom sediment from the detention basin were all at least twice as concentrated compared to sediment collected from 1.5 feet deeper. Similarly, concentrations of 28 polycyclic aromatic hydrocarbon compounds were

  5. Design of Improved Stormwater Management System for the Federal ...

    African Journals Online (AJOL)

    Stormwater management is becoming a problem in many cities due to rapid urbanization and poor infrastructure. Proper drainage system conveys stormwater from the road to a suitable disposal area. FUTA is well planned with good networks of roads. However, many of them are without functioning drains. The paper ...

  6. 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 syst...

  7. National Stormwater Calculator User's Guide – VERSION 1.1

    Science.gov (United States)

    This document is the user's guide for running EPA's National Stormwater Calculator (http://www.epa.gov/nrmrl/wswrd/wq/models/swc/). The National Stormwater Calculator is a simple to use tool for computing small site hydrology for any location within the US.

  8. The role of trees in urban stormwater management | Science ...

    Science.gov (United States)

    Urban impervious surfaces convert precipitation to stormwater runoff, which causes water quality and quantity problems. While traditional stormwater management has relied on gray infrastructure such as piped conveyances to collect and convey stormwater to wastewater treatment facilities or into surface waters, cities are exploring green infrastructure to manage stormwater at its source. Decentralized green infrastructure leverages the capabilities of soil and vegetation to infiltrate, redistribute, and otherwise store stormwater volume, with the potential to realize ancillary environmental, social, and economic benefits. To date, green infrastructure science and practice have largely focused on infiltration-based technologies that include rain gardens, bioswales, and permeable pavements. However, a narrow focus on infiltration overlooks other losses from the hydrologic cycle, and we propose that arboriculture – the cultivation of trees and other woody plants – deserves additional consideration as a stormwater control measure. Trees interact with the urban hydrologic cycle by intercepting incoming precipitation, removing water from the soil via transpiration, enhancing infiltration, and bolstering the performance of other green infrastructure technologies. However, many of these interactions are inadequately understood, particularly at spatial and temporal scales relevant to stormwater management. As such, the reliable use of trees for stormwater control depe

  9. 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...

  10. TRADING ALLOWANCES FOR STORMWATER CONTROL: HYDROLOGY AND OPPORTUNITY COSTS

    Science.gov (United States)

    Excess stormwater runoff is a serious problem in a large number of urban areas, causing flooding, water pollution, groundwater recharge deficits and ecological damage to urban streams. It has been posited that to mitigate the effects of excess stormwater runoff, policy makers cou...

  11. Modelling the fate of organic micropollutants in stormwater ponds

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Eriksson, Eva; Ledin, Anna

    2011-01-01

    Urban water managers need to estimate the potential removal of organic micropollutants (MP) in stormwater treatment systems to support MP pollution control strategies. This study documents how the potential removal of organic MP in stormwater treatment systems can be quantified by using multimedia...... 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...... 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...

  12. Management of Urban Stormwater Runoff in the Chesapeake Bay Watershed

    Science.gov (United States)

    Hogan, Dianna M.

    2008-01-01

    Urban and suburban development is associated with elevated nutrients, sediment, and other pollutants in stormwater runoff, impacting the physical and environmental health of area streams and downstream water bodies such as the Chesapeake Bay. Stormwater management facilities, also known as Best Management Practices (BMPs), are increasingly being used in urban areas to replace functions, such as flood protection and water quality improvement, originally performed by wetlands and riparian areas. Scientists from the U.S. Geological Survey (USGS) have partnered with local, academic, and other Federal agency scientists to better understand the effectiveness of different stormwater management systems with respect to Chesapeake Bay health. Management of stormwater runoff is necessary in urban areas to address flooding and water quality concerns. Improving our understanding of what stormwater management actions may be best suited for different types of developed areas could help protect the environmental health of downstream water bodies that ultimately receive runoff from urban landscapes.

  13. 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....

  14. 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.

  15. Assessing roadway contributions to stormwater flows, concentrations, and loads with the StreamStats application

    Science.gov (United States)

    Stonewall, Adam; Granato, Gregory E.; Haluska, Tana L.

    2018-01-01

    The Oregon Department of Transportation (ODOT) and other state departments of transportation need quantitative information about the percentages of different land cover categories above any given stream crossing in the state to assess and address roadway contributions to water-quality impairments and resulting total maximum daily loads. The U.S. Geological Survey, in cooperation with ODOT and the FHWA, added roadway and land cover information to the online StreamStats application to facilitate analysis of stormwater runoff contributions from different land covers. Analysis of 25 delineated basins with drainage areas of about 100 mi2 indicates the diversity of land covers in the Willamette Valley, Oregon. On average, agricultural, developed, and undeveloped land covers comprise 15%, 2.3%, and 82% of these basin areas. On average, these basins contained about 10 mi of state highways and 222 mi of non-state roads. The Stochastic Empirical Loading and Dilution Model was used with available water-quality data to simulate long-term yields of total phosphorus from highways, non-highway roadways, and agricultural, developed, and undeveloped areas. These yields were applied to land cover areas obtained from StreamStats for the Willamette River above Wilsonville, Oregon. This analysis indicated that highway yields were larger than yields from other land covers because highway runoff concentrations were higher than other land covers and the highway is fully impervious. However, the total highway area was a fraction of the other land covers. Accordingly, highway runoff mitigation measures can be effective for managing water quality locally, they may have limited effect on achieving basin-wide stormwater reduction goals.

  16. Development of multiple linear regression models for predicting the stormwater quality of urban sub-watersheds.

    Science.gov (United States)

    Arora, Amarpreet S; Reddy, Akepati S

    2014-01-01

    Stormwater management at urban sub-watershed level has been envisioned to include stormwater collection, treatment, and disposal of treated stormwater through groundwater recharging. Sizing, operation and control of the stormwater management systems require information on the quantities and characteristics of the stormwater generated. Stormwater characteristics depend upon dry spell between two successive rainfall events, intensity of rainfall and watershed characteristics. However, sampling and analysis of stormwater, spanning only few rainfall events, provides insufficient information on the characteristics. An attempt has been made in the present study to assess the stormwater characteristics through regression modeling. Stormwater of five sub-watersheds of Patiala city were sampled and analyzed. The results obtained were related with the antecedent dry periods and with the intensity of the rainfall event through regression modeling. Obtained regression models were used to assess the stormwater quality for various antecedent dry periods and rainfall event intensities.

  17. Fire and smoke retardants

    Science.gov (United States)

    Drews, M. J.

    Despite a reduction in Federal regulatory activity, research concerned with flame retardancy and smoke suppression in the private sector appears to be increasing. This trend seem related to the increased utilization of plastics for end uses which traditionally have employed metal or wood products. As a result, new markets have appeared for thermally stable and fire resistance thermoplastic materials, and this in turn has spurred research and development activity. In addition, public awareness of the dangers associated with fire has increased as a result of several highly publicized hotel and restaurant fires within the past two years. The consumers recognition of flammability characteristics as important materials property considerations has increased. The current status of fire and smoke retardant chemistry and research are summarized.

  18. Flame Retardant Epoxy Resins

    Science.gov (United States)

    Thompson, C. M.; Smith, J. G., Jr.; Connell, J. W.; Hergenrother, P. M.; Lyon, R. E.

    2004-01-01

    As part of a program to develop fire resistant exterior composite structures for future subsonic commercial aircraft, flame retardant epoxy resins are under investigation. Epoxies and their curing agents (aromatic diamines) containing phosphorus were synthesized and used to prepare epoxy formulations. Phosphorus was incorporated within the backbone of the epoxy resin and not used as an additive. The resulting cured epoxies were characterized by thermogravimetric analysis, propane torch test, elemental analysis and microscale combustion calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness of plaques of several cured formulations was determined on single-edge notched bend specimens. The chemistry and properties of these new epoxy formulations are discussed.

  19. 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

  20. Assessment of retention basin volume and outlet capacity in urban ...

    Indian Academy of Sciences (India)

    The quality of river water or other surface waters is detrimentally affected by the contaminants carried by the rainfall runoff in urban areas. The control of pollution moved by rainfall runoff is achieved by installing outlets and small retention basins in stormwater collection systems, thereby allowing only a certain amount of ...

  1. Assessment of retention basin volume and outlet capacity in urban ...

    Indian Academy of Sciences (India)

    Mehmet A Yurdusev et al. The level of contaminants transported from the cities to such water bodies is monitored by installing small retention basins in stormwater drain systems connected to the outlets. The idea here is to allow some amount of rain water to overflow from the outlets and the rest to be led either to treatment ...

  2. Price Endogeneity and Marginal Cost Effects on Incentive Compatible Stormwater Management Policies

    OpenAIRE

    Huber, Matthew C.; Willis, David B.; Hayes, John C.; Privette, Charles V., III

    2010-01-01

    Incentive based stormwater management policies offer the prospect of reducing urban stormwater runoff while increasing developer profits. An incentive compatible Stormwater Banking Program (SBP) is presented that allows developers to build at higher residential densities in exchange for including low impact stormwater Best Management Practices (BMPs) in the development’s stormwater management infrastructure. Price endogeneity presents itself when the smaller residential lots created by buildi...

  3. Methods of assessment of stormwater sediments quality

    Directory of Open Access Journals (Sweden)

    Sałata Aleksandra

    2017-01-01

    Full Text Available Concentration of heavy metal (cadmium, copper, chromium, nickel, lead and zinc in sediments collected from the stormwater treatment plant located in the urbanised catchment were investigated using geo-accumulation index and enrichment factor to determine metal accumulation and pollution status. Total metal concentrations varied widely in studied materials and the mean values were higher than their background values. The Igeo results indicate that tested sediments were uncontaminated with respect to Cd. The study area is moderately to strongly contaminated with Zn, Pb and Cu. The other elements are within the scope moderate contamination.

  4. The stormwater management manual for Malaysia

    International Nuclear Information System (INIS)

    Md Nasir Md Noh

    2006-01-01

    The government of Malaysia considers land and water as two very important natural resources. Consequently, the conservation practice of these natural resources remain top priority agenda with various laws and policies apart from manuals and guidelines available for practitioners to follow right from planning, design and implementation stages. Among the laws and regulations are national land code, land conservation act, local government act, street, drainage and building act, town and country planning act, and environmental quality act among others. In addition, stormwater management manual for Malaysia developed by department of irrigation and drainage, guidelines on the prevention and control of soil erosion and siltation in Malaysia developed by department of environment, standard specification for road works established by public works department, use of flood detention ponds as part of open space set up by department of town and country planning, and guideline for agricultural development at slope terrain published by department of agriculture are some of the established manuals and guidelines utilized around the country. The stormwater management manual for malaysia (msma) is the latest of the series of guidelines available in the country for inculcating up to date stormwater management apart from ensuring sustainable soil and water conservation practice in Malaysia. This manual has been published in 2000 and started to be utilized since 1 January 2001. Ever since msma has been widely used for the planning, design and implementation of various land development activities in the country. Among the key points highlighted in this manual are water quantity control and water quality control. Water quantity control focuses on the flash flood control technique due to the increase rate of water flowing out of developed areas while water quality control meant for the controlled of non-point source pollution generated by developed areas by contemplating on the best

  5. Retardo mental Mental retardation

    Directory of Open Access Journals (Sweden)

    Marcio M. Vasconcelos

    2004-04-01

    Full Text Available OBJETIVO: Esta revisão aborda as recentes descobertas da neurobiologia do retardo mental, enfatizando os novos recursos da citogenética, das técnicas moleculares e da neurorradiologia para esclarecer o diagnóstico. FONTES DE DADOS: O autor pesquisou o banco de dados MEDLINE da National Library of Medicine utilizando as palavras-chave "mental retardation", "developmental disability", "child" e "adolescent" em diferentes combinações, abrangendo o período de janeiro de 2000 a outubro de 2003. Também foram utilizados os bancos de dados das revistas científicas Pediatrics e New England Journal of Medicine através da palavra-chave "mental retardation". No total, o autor consultou cerca de 1.500 títulos de artigos e 500 resumos, e teve acesso direto a 150 artigos completos pertinentes. Quando oportuno, algumas referências dos artigos consultados também foram consideradas. O site Online Mendelian Inheritance in Man foi utilizado como fonte de informações em genética clínica. SÍNTESE DOS DADOS: Em outubro de 2003, o total de síndromes genéticas associadas a retardo mental chegou a 1.149. Considerando-se o conjunto das causas genéticas ou ambientais e congênitas ou adquiridas de retardo mental, a avaliação diagnóstica atual é capaz de esclarecer a etiologia em 50 a 70% dos casos. CONCLUSÕES: O autor sugere uma avaliação diagnóstica do retardo mental em etapas lógicas, visando ao uso racional dos dispendiosos recursos da citogenética, biologia molecular e neuroimagem.OBJECTIVE: This paper describes recent advances in the neurobiology of mental retardation, emphasizing new diagnostic resources provided by cytogenetics, molecular testing, and neuroimaging. SOURCES OF DATA: MEDLINE (January 2000 through October 2003, using the following key words: mental retardation, developmental disability, child, and adolescent. Search of the Pediatrics and New England Journal of Medicine websites using the key word mental retardation. The

  6. 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.

  7. 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.

  8. Stormwater contaminant loading following southern California wildfires.

    Science.gov (United States)

    Stein, Eric D; Brown, Jeffrey S; Hogue, Terri S; Burke, Megan P; Kinoshita, Alicia

    2012-11-01

    Contaminant loading associated with stormwater runoff from recently burned areas is poorly understood, despite the fact that it has the potential to affect downstream water quality. The goal of the present study is to assess regional patterns of runoff and contaminant loading from wildfires in urban fringe areas of southern California. Postfire stormwater runoff was sampled from five wildfires that each burned between 115 and 658 km(2) of natural open space between 2003 and 2009. Between two and five storm events were sampled per site over the first one to two years following the fires for basic constituents, metals, nutrients, total suspended solids, and polycyclic aromatic hydrocarbons (PAHs). Results were compared to data from 16 unburned natural areas and six developed sites. Mean copper, lead, and zinc flux (kg/km(2)) were between 112- and 736-fold higher from burned catchments and total phosphorus was up to 921-fold higher compared to unburned natural areas. Polycyclic aromatic hydrocarbon flux was four times greater from burned areas than from adjacent urban areas. Ash fallout on nearby unburned watersheds also resulted in a threefold increase in metals and PAHs. Attenuation of elevated concentration and flux values appears to be driven mainly by rainfall magnitude. Contaminant loading from burned landscapes has the potential to be a substantial contribution to the total annual load to downstream areas in the first several years following fires. Copyright © 2012 SETAC.

  9. Stormwater Priority Pollutants Versus Surface Water Quality Criteria

    DEFF Research Database (Denmark)

    Eriksson, Eva; Ledin, Anna; Baun, Anders

    2011-01-01

    Stormwater in urban areas comprises of a substantial part of the urban water cycle, dominating the flow in many small urban streams, and the pollution levels are sizeable. No stormwater quality criteria were found here and no European or national emission limit values exist. Stormwater pollutants...... however are present in levels exceeding most of the regulated surface water quality criteria and environmental quality standards. Therefore catchment characterisation is needed to chose suitable treatment prior to discharge into receiving surface waters, as the mixing may be insufficient in small streams....

  10. 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

  11. 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...... reaches), and non-structural BMPs, such as controls of chemicals or building materials, and street sweeping. The available knowledge of stormwater BMPs performance in pollution control is inconsistent and the effect of various BMPs on receiving water quality is either poorly understood, or not known....... 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....

  12. Testing of ultra-urban stormwater best management practices.

    Science.gov (United States)

    2001-01-01

    Ultra urban areas where conventional best management practices (BMPs) are neither feasible nor cost-effective present a challenge to stormwater management. Although new BMPs have been developed for such space limited environments, the field performan...

  13. Engaging Social Capital for Decentralized Urban Stormwater Management

    Science.gov (United States)

    Decentralized approaches to urban stormwater management, whereby installations of green infrastructure (e.g., rain gardens, bioswales, and constructed wetlands) are dispersed throughout a management area, are cost-effective solutions with co-benefits beyond water abatement. Inste...

  14. Catalyzing municipal stakeholder engagement for stormwater funding solutions

    Science.gov (United States)

    Stormwater runoff contributes to a range of water quality issues in coastal systems, including eutrophication, contamination of water resources, and reduced value to coastal residents. However, managing runoff sources and meeting permit requirements can be costly. Municipalities ...

  15. Cistern Performance for Stormwater Management in Camden, NJ - abstract

    Science.gov (United States)

    The Camden County Municipal Utilities Authority (CCMUA) installed different types of green infrastructure Stormwater Control Measures (SCMs) at locations around the city of Camden, NJ. The installed SCMs include cisterns. Cisterns provide a cost effective approach to reduce st...

  16. Cistern Performance for Stormwater Management in Camden, NJ - presentation

    Science.gov (United States)

    The Camden County Municipal Utilities Authority (CCMUA) installed different types of green infrastructure Stormwater Control Measures (SCMs) at locations around the city of Camden, NJ. The installed SCMs include cisterns. Cisterns provide a cost effective approach to reduce st...

  17. The effect of particle size distribution on the design of urban stormwater control measures

    Science.gov (United States)

    Selbig, William R.; Fienen, Michael N.; Horwatich, Judy A.; Bannerman, Roger T.

    2016-01-01

    An urban pollutant loading model was used to demonstrate how incorrect assumptions on the particle size distribution (PSD) in urban runoff can alter the design characteristics of stormwater control measures (SCMs) used to remove solids in stormwater. Field-measured PSD, although highly variable, is generally coarser than the widely-accepted PSD characterized by the Nationwide Urban Runoff Program (NURP). PSDs can be predicted based on environmental surrogate data. There were no appreciable differences in predicted PSD when grouped by season. Model simulations of a wet detention pond and catch basin showed a much smaller surface area is needed to achieve the same level of solids removal using the median value of field-measured PSD as compared to NURP PSD. Therefore, SCMs that used the NURP PSD in the design process could be unnecessarily oversized. The median of measured PSDs, although more site-specific than NURP PSDs, could still misrepresent the efficiency of an SCM because it may not adequately capture the variability of individual runoff events. Future pollutant loading models may account for this variability through regression with environmental surrogates, but until then, without proper site characterization, the adoption of a single PSD to represent all runoff conditions may result in SCMs that are under- or over-sized, rendering them ineffective or unnecessarily costly.

  18. Urban stormwater runoff: a new class of environmental flow problem.

    Science.gov (United States)

    Walsh, Christopher J; Fletcher, Tim D; Burns, Matthew J

    2012-01-01

    Environmental flow assessment frameworks have begun to consider changes to flow regimes resulting from land-use change. Urban stormwater runoff, which degrades streams through altered volume, pattern and quality of flow, presents a problem that challenges dominant approaches to stormwater and water resource management, and to environmental flow assessment. We used evidence of ecological response to different stormwater drainage systems to develop methods for input to environmental flow assessment. We identified the nature of hydrologic change resulting from conventional urban stormwater runoff, and the mechanisms by which such hydrologic change is prevented in streams where ecological condition has been protected. We also quantified the increase in total volume resulting from urban stormwater runoff, by comparing annual streamflow volumes from undeveloped catchments with the volumes that would run off impervious surfaces under the same rainfall regimes. In catchments with as little as 5-10% total imperviousness, conventional stormwater drainage, associated with poor in-stream ecological condition, reduces contributions to baseflows and increases the frequency and magnitude of storm flows, but in similarly impervious catchments in which streams retain good ecological condition, informal drainage to forested hillslopes, without a direct piped discharge to the stream, results in little such hydrologic change. In urbanized catchments, dispersed urban stormwater retention measures can potentially protect urban stream ecosystems by mimicking the hydrologic effects of informal drainage, if sufficient water is harvested and kept out of the stream, and if discharged water is treated to a suitable quality. Urban stormwater is a new class of environmental flow problem: one that requires reduction of a large excess volume of water to maintain riverine ecological integrity. It is the best type of problem, because solving it provides an opportunity to solve other problems such

  19. Urban stormwater runoff: a new class of environmental flow problem.

    Directory of Open Access Journals (Sweden)

    Christopher J Walsh

    Full Text Available Environmental flow assessment frameworks have begun to consider changes to flow regimes resulting from land-use change. Urban stormwater runoff, which degrades streams through altered volume, pattern and quality of flow, presents a problem that challenges dominant approaches to stormwater and water resource management, and to environmental flow assessment. We used evidence of ecological response to different stormwater drainage systems to develop methods for input to environmental flow assessment. We identified the nature of hydrologic change resulting from conventional urban stormwater runoff, and the mechanisms by which such hydrologic change is prevented in streams where ecological condition has been protected. We also quantified the increase in total volume resulting from urban stormwater runoff, by comparing annual streamflow volumes from undeveloped catchments with the volumes that would run off impervious surfaces under the same rainfall regimes. In catchments with as little as 5-10% total imperviousness, conventional stormwater drainage, associated with poor in-stream ecological condition, reduces contributions to baseflows and increases the frequency and magnitude of storm flows, but in similarly impervious catchments in which streams retain good ecological condition, informal drainage to forested hillslopes, without a direct piped discharge to the stream, results in little such hydrologic change. In urbanized catchments, dispersed urban stormwater retention measures can potentially protect urban stream ecosystems by mimicking the hydrologic effects of informal drainage, if sufficient water is harvested and kept out of the stream, and if discharged water is treated to a suitable quality. Urban stormwater is a new class of environmental flow problem: one that requires reduction of a large excess volume of water to maintain riverine ecological integrity. It is the best type of problem, because solving it provides an opportunity to solve

  20. Effects of two stormwater management methods on the quality of water in the upper Biscayne aquifer at two commercial areas in Dade County, Florida

    Science.gov (United States)

    McKenzie, D.J.; Irwin, G.A.

    1988-01-01

    This study is part of a continued effort to assess the effects of urban stormwater recharge on the water quality of the Biscayne aquifer in southeast Florida. In this report, the water-quality effects on shallow ground water resulting from stormwater disposal by exfiltration trench and grassy swale were investigated at two small commercial areas in Dade County, Florida. One study area (airport ) was located near the Miami International Airport and had a drainage area of about 10 acres overlying a sandy soil; the other study area ( free zone ) was located at the Miami International Free Trade Zone and had a drainage area of about 20 acres overlying limestone. The monitoring design for each study area consisted of seven sites and included water-quality sampling of the stormwater in the catch basin of the exfiltration trench, ground water from two wells 1 foot from the trench (trench wells), two wells 20 feet from the trench, and ground water from two wells at the swale from April 1985 through May 1986. Eleven water-quality variables (target variables) commonly found in high levels in urban stormwater runoff were used as tracers to estimate possible changes in ground-water quality that may have been caused by stormwater recharge. Comparison of the distribution of target variables indicated that the concentrations tended to be greater in the stormwater in the exfiltration trench than in water from the two wells 1 foot from the trench at both study areas. The concentration difference for several target variables was statistically significant at the 5-percent level. Lead, for example, had median concentrations of 23 and 4 micrograms per liter, respectively, in stormwater and water from the two trench wells at the airport study area, and 38 and 2 micrograms per liter, respectively, in stormwater and groundwater at the free zone. Similar reductions in concentrations between stormwater and water from the two trench wells were indicated for zinc at both study areas and also

  1. X-linked mental retardation.

    NARCIS (Netherlands)

    Ropers, H.H.; Hamel, B.C.J.

    2005-01-01

    Genetic factors have an important role in the aetiology of mental retardation. However, their contribution is often underestimated because in developed countries, severely affected patients are mainly sporadic cases and familial cases are rare. X-chromosomal mental retardation is the exception to

  2. Air quality considerations for stormwater green street design.

    Science.gov (United States)

    Shaneyfelt, Kathryn M; Anderson, Andrew R; Kumar, Prashant; Hunt, William F

    2017-12-01

    Green streets are increasingly being used as a stormwater management strategy to mitigate stormwater runoff at its source while providing other environmental and societal benefits, including connecting pedestrians to the street. Simultaneously, human exposure to particulate matter from urban transportation is of major concern worldwide due to the proximity of pedestrians, drivers, and cyclists to the emission sources. Vegetation used for stormwater treatment can help designers limit the exposure of people to air pollutants. This goal can be achieved through the deliberate placement of green streets, along with strategic planting schemes that maximize pollutant dispersion. This communication presents general design considerations for green streets that combine stormwater management and air quality goals. There is currently limited guidance on designing green streets for air quality considerations; this is the first communication to offer suggestions and advice for the design of green stormwater streets in regards to their effects on air quality. Street characteristics including (1) the width to height ratio of the street to the buildings, (2) the type of trees and their location, and (3) any prevailing winds can have an impact on pollutant concentrations within the street and along sidewalks. Vegetation within stormwater control measures has the ability to reduce particulate matter concentrations; however, it must be carefully selected and placed within the green street to promote the dispersion of air flow. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Hydrologic impact of urbanization with extensive stormwater infiltration

    DEFF Research Database (Denmark)

    Locatelli, Luca; Mark, Ole; Mikkelsen, Peter Steen

    2017-01-01

    This paper presents a novel modeling analysis of a 40-year-long dataset to examine the impact of urbanization, with widespread stormwater infiltration, on groundwater levels and the water balance of a watershed. A dataset on the hydrologic impact of urbanization with extensive stormwater infiltra......This paper presents a novel modeling analysis of a 40-year-long dataset to examine the impact of urbanization, with widespread stormwater infiltration, on groundwater levels and the water balance of a watershed. A dataset on the hydrologic impact of urbanization with extensive stormwater...... to setup, calibrate and validate a coupled MIKE SHE-MIKE URBAN groundwater model and the model is used to quantify the extent of groundwater rise as a result of the urbanization process. The modeled urbanization processes included the irrigation of new established private and public gardens, the reduction...... of evapotranspiration due to a decrease in green areas, and the development of artificial stormwater infiltration. The study demonstrates that urbanization with stormwater infiltration affects the whole catchment water balance, increasing recharge and decreasing evapotranspiration. These changes lead to a rise...

  4. Yorktowne Square condominium green roof retrofit and stormwater management plan

    Energy Technology Data Exchange (ETDEWEB)

    Perry, M.D. [Building Logics Inc., Virginia Beach, VA (United States)

    2005-07-01

    This paper provided details of a green roof retrofit and and stormwater management plan developed for the Yorktowne Square Condominiums, a 15.3 acre site located in the highly developed county of Fairfax, Virginia. The 4700 square foot green roof system was installed as the first step to implement an effective stormwater management plan. The loss of forested areas and increased impervious surfaces in the region has meant that stormwater drainage in the region is increasingly allowing trash, sediment and other pollutants to enter the Chesapeake Bay. A lightweight EnviroTech green roof system was used to address structural concerns due to the age of the buildings. The specialized modified bitumen membrane incorporated waterproofing, root barrier, water retention and drainage systems in a single layer. The Yorktowne plan will reduce the nutrient load in the Chesapeake Bay and maintain the 40 per cent nutrient reduction goal agreed to in 1987, in addition to not using pesticides, fertilizers or herbicides. Studies have shown that the living roof has increased stormwater retention by up to 80 per cent. The roof has been the subject of television shows and newspaper articles. It was concluded that Yorktowne has become a model for residential and business communities by demonstrating how green roofs and other stormwater management designs can be implemented to improve water quality, decrease erosive stormwater, and conserve resources in the Chesapeake Bay watershed. 1 fig.

  5. Beyond best management practices: pelagic biogeochemical dynamics in urban stormwater ponds.

    Science.gov (United States)

    Williams, Clayton J; Frost, Paul C; Xenopoulos, Marguerite A

    2013-09-01

    Urban stormwater ponds are considered to be a best management practice for flood control and the protection of downstream aquatic ecosystems from excess suspended solids and other contaminants. Following this, urban ponds are assumed to operate as unreactive settling basins, whereby their overall effectiveness in water treatment is strictly controlled by physical processes. However, pelagic microbial biogeochemical dynamics could be significant contributors to nutrient and carbon cycling in these small, constructed aquatic systems. In the present study, we examined pelagic biogeochemical dynamics in 26 stormwater ponds located in southern Ontario, Canada, during late summer. Initially, we tested to see if total suspended solids (TSS) concentration, which provides a measure of catchment disturbance, landscape stability, and pond performance, could be used as an indirect predictor of plankton stocks in stormwater ponds. Structural equation modeling (SEM) using TSS as a surrogate for external loading suggested that TSS was an imperfect predictor. TSS masked plankton-nutrient relationships and appeared to reflect autochthonous production moreso than external forces. When TSS was excluded, the SEM model explained a large amount of the variation in dissolved organic matter (DOM) characteristics (55-75%) but a small amount of the variation in plankton stocks (3-38%). Plankton stocks were correlated positively with particulate nutrients and extracellular enzyme activities, suggesting rapid recycling of the fixed nutrient and carbon pool with consequential effects on DOM. DOM characteristics across the ponds were mainly of autochthonous origin. Humic matter from the watershed formed a larger part of the DOM pool only in ponds with low productivity and low dissolved organic carbon concentrations. Our results suggest that in these small, high nutrient systems internal processes might outweigh the impact of the landscape on carbon cycles. Hence, the overall benefit that

  6. Spatial and Temporal Variation in Local Stormwater Infrastructure Use and Stormwater Management Paradigms over the 20th Century

    OpenAIRE

    Rebecca L. Hale

    2016-01-01

    Stormwater management has significant consequences for urban hydrology, water quality, and flood risk, and has changed substantially over history, but it is unknown how these paradigm shifts play out at the local scale and whether local changes in stormwater infrastructure use follow similar trajectories across cities. This research addressed: (1) How does current infrastructure use and past infrastructure transitions vary across three cities with similar biophysical and climatic contexts but...

  7. Synergistic benefits between stormwater management measures and a new pricing system for stormwater in the City of Hamburg.

    Science.gov (United States)

    Bertram, N P; Waldhoff, A; Bischoff, G; Ziegler, J; Meinzinger, F; Skambraks, A-K

    2017-09-01

    Hamburg is a growing metropolitan city. The increase in sealed surfaces of about 0.36% per year and the subsequent increased runoff impacts on the city's wastewater infrastructure. Further potential risks to the drainage infrastructure arise also from effects of climate change, e.g. increased intensity and frequency of heavy rainfalls. These challenges were addressed in the Rain InfraStructure Adaption (RISA) project conducted 2009-2015 by HAMBURG WASSER and the State Ministry for Environment and Energy, supported by several municipal stakeholders. RISA addressed intensifying conflicts in the context of urban development and stormwater management at that time. Major results of the project are improvements and recommendations for adequate consideration of stormwater management issues during urban planning as well as new funding mechanisms for stormwater management measures. The latter topic resulted in the introduction of a separated stormwater charge based on the amount of sealed area connected to the sewer system of each property. For both undertakings - the RISA project and the introduction of the separated stormwater charge - a novel, comprehensive, digital database was built. Today, these geographical information system (GIS)-based data offer various scale-independent analysis and information opportunities, which facilitate the day-to-day business of HAMBURG WASSER and stormwater management practice in Hamburg.

  8. Local Equilibrium and Retardation Revisited.

    Science.gov (United States)

    Hansen, Scott K; Vesselinov, Velimir V

    2018-01-01

    In modeling solute transport with mobile-immobile mass transfer (MIMT), it is common to use an advection-dispersion equation (ADE) with a retardation factor, or retarded ADE. This is commonly referred to as making the local equilibrium assumption (LEA). Assuming local equilibrium, Eulerian textbook treatments derive the retarded ADE, ostensibly exactly. However, other authors have presented rigorous mathematical derivations of the dispersive effect of MIMT, applicable even in the case of arbitrarily fast mass transfer. We resolve the apparent contradiction between these seemingly exact derivations by adopting a Lagrangian point of view. We show that local equilibrium constrains the expected time immobile, whereas the retarded ADE actually embeds a stronger, nonphysical, constraint: that all particles spend the same amount of every time increment immobile. Eulerian derivations of the retarded ADE thus silently commit the gambler's fallacy, leading them to ignore dispersion due to mass transfer that is correctly modeled by other approaches. We then present a particle tracking simulation illustrating how poor an approximation the retarded ADE may be, even when mobile and immobile plumes are continually near local equilibrium. We note that classic "LEA" (actually, retarded ADE validity) criteria test for insignificance of MIMT-driven dispersion relative to hydrodynamic dispersion, rather than for local equilibrium. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  9. December 2014 Sustainable Financing Forum for Faster, Cheaper, Greener Urban Stormwater Retrofits

    Science.gov (United States)

    December 2014 Sustainable Stormwater Financing Forum that focused on building sustainable stormwater infrastructure and economic health through Community-Based Public-Private Partnerships (CBP3s) and smart financing tools.

  10. Stormwater Management for Federal Facilities under Section 438 of the Energy Independence and Security Act

    Science.gov (United States)

    Federal agencies are required to reduce stormwater runoff from federal development and redevelopment projects to protect water resources. Options include a variety of stormwater management practices like green infrastructure or low impact development

  11. Spatial and temporal structure within moisture measurements of a stormwater control system

    Science.gov (United States)

    Moisture sensing is a mature soil research technology commonly applied to agriculture. Such sensors may be appropriated for use in novel stormwater research applications. Knowledge of moisture (with respect to space and time) in infiltration based stormwater control measures (SCM...

  12. 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...

  13. 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...

  14. Innovative Stormwater Quality Tools by SARA for Holistic Watershed Master Planning

    Science.gov (United States)

    Thomas, S. M.; Su, Y. C.; Hummel, P. R.

    2016-12-01

    Stormwater management strategies such as Best Management Practices (BMP) and Low-Impact Development (LID) have increasingly gained attention in urban runoff control, becoming vital to holistic watershed master plans. These strategies can help address existing water quality impairments and support regulatory compliance, as well as guide planning and management of future development when substantial population growth and urbanization is projected to occur. However, past efforts have been limited to qualitative planning due to the lack of suitable tools to conduct quantitative assessment. The San Antonio River Authority (SARA), with the assistance of Lockwood, Andrews & Newnam, Inc. (LAN) and AQUA TERRA Consultants (a division of RESPEC), developed comprehensive hydrodynamic and water quality models using the Hydrological Simulation Program-FORTRAN (HSPF) for several urban watersheds in the San Antonio River Basin. These models enabled watershed management to look at water quality issues on a more refined temporal and spatial scale than the limited monitoring data. They also provided a means to locate and quantify potential water quality impairments and evaluate the effects of mitigation measures. To support the models, a suite of software tools were developed. including: 1) SARA Timeseries Utility Tool for managing and processing of large model timeseries files, 2) SARA Load Reduction Tool to determine load reductions needed to achieve screening levels for each modeled constituent on a sub-basin basis, and 3) SARA Enhanced BMP Tool to determine the optimal combination of BMP types and units needed to achieve the required load reductions. Using these SARA models and tools, water quality agencies and stormwater professionals can determine the optimal combinations of BMP/LID to accomplish their goals and save substantial stormwater infrastructure and management costs. The tools can also help regulators and permittees evaluate the feasibility of achieving compliance

  15. Replacing natural wetlands with stormwater management facilities: biophysical and perceived social values

    OpenAIRE

    Rooney, R.C.; Foote, L.; Krogman, N.; Pattison, J.K.; Wilson, M.J.; Bayley, S.E.

    2015-01-01

    Urban expansion replaces wetlands of natural origin with artificial stormwater management facilities. The literature suggests that efforts to mimic natural wetlands in the design of stormwater facilities can expand the provision of ecosystem services. Policy developments seek to capitalize on these improvements, encouraging developers to build stormwater wetlands in place of stormwater ponds; however, few have compared the biophysical values and social perceptions of these created wetlands to...

  16. Facing Stormwater Management Challenges at a Southeastern Army Installation: US Army Garrison Fort Gordon

    Science.gov (United States)

    2012-05-24

    the Solution to Stormwater Pollution at Fort Gordon ~trriGffiG 01 ~~~ • Oil , grease , heavy metals and toxic chemicals from motor vehicles...etc.) into the storm drains. Sinw stormwater drains are not oonnectacl to tl’e wastewater treatment system, the polluted stormwat:er Is trcn...examples of illicit discharge materials include paint, oil , antifreeze, yancl waste, etc. These pollutants degrade water qufllity anrl threaten

  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. Stormwater wetlands can function as ecological traps for urban frogs.

    Science.gov (United States)

    Sievers, Michael; Parris, Kirsten M; Swearer, Stephen E; Hale, Robin

    2018-03-01

    Around cities, natural wetlands are rapidly being destroyed and replaced with wetlands constructed to treat stormwater. Although the intended purpose of these wetlands is to manage urban stormwater, they are inhabited by wildlife that might be exposed to contaminants. These effects will be exacerbated if animals are unable to differentiate between stormwater treatment wetlands of varying quality and some function as 'ecological traps' (i.e. habitats that animals prefer despite fitness being lower than in other habitats). To examine if urban stormwater wetlands can be ecological traps for frogs, we tested if survival, metamorphosis-related measures and predator avoidance behaviours of frogs differed within mesocosms that simulated stormwater wetlands with different contaminant levels, and paired this with a natural oviposition experiment to assess breeding-site preferences. We provide the first empirical evidence that these wetlands can function as ecological traps for frogs. Tadpoles had lower survival and were less responsive to predator olfactory cues when raised in more polluted stormwater wetlands, but also reached metamorphosis earlier and at a larger size. A greater size at metamorphosis was likely a result of increased per capita food availability due to higher mortality combined with eutrophication, although other compensatory effects such as selective-mortality removing smaller individuals from low-quality mesocosms may also explain these results. Breeding adults laid comparable numbers of eggs across wetlands with high and low contaminant levels, indicating no avoidance of the former. Since stormwater treatment wetlands are often the only available aquatic habitat in urban landscapes we need to better understand how they perform as habitats to guide management decisions that mitigate their potential ecological costs. This may include improving wetland quality so that fitness is no longer compromised, preventing colonisation by animals, altering the cues

  19. Neurotoxicity of brominated flame retardants

    Science.gov (United States)

    Polybrominated diphenyl ethers (PBDEs) have been commonly used as commercial flame retardants in a variety of products including plastics and textiles. Despite their decreasing usage worldwide, congeners continue to accumulate in the environment, including soil, dust, food, anima...

  20. Can earthworms survive fire retardants?

    Science.gov (United States)

    Beyer, W.N.; Olson, A.

    1996-01-01

    Most common fire retardants are foams or are similar to common agricultural fertilizers, such as ammonium sulfate and ammonium phosphate. Although fire retardants are widely applied to soils, we lack basic information about their toxicities to soil organisms. We measured the toxicity of five fire retardants (Firetrol LCG-R, Firetrol GTS-R, Silv-Ex Foam Concentrate, Phos-chek D-75, and Phos-chek WD-881) to earthworms using the pesticide toxicity test developed for earthworms by the European Economic Community. None was lethal at 1,000 ppm in the soil, which was suggested as a relatively high exposure under normal applications. We concluded that the fire retardants tested are relatively nontoxic to soil organisms compared with other environmental chemicals and that they probably do not reduce earthworm populations when applied under usual firefighting conditions.

  1. Effects of landscape-based green infrastructure on stormwater ...

    Science.gov (United States)

    The development of impervious surfaces in urban and suburban catchments affects their hydrological behavior by decreasing infiltration, increasing peak hydrograph response following rainfall events, and ultimately increasing the total volume of water and mass of pollutants reaching streams. These changes have deleterious effects on downstream surface waters. Consequently, strategies to mitigate these impacts are now components of contemporary urban development and stormwater management. This study evaluates the effectiveness of landscape green infrastructure (GI) in reducing stormwater runoff volumes and controlling peak flows in four subdivision-scale suburban catchments (1.88 – 12.97 acres) in Montgomery County, MD, USA. Stormwater flow rates during runoff events were measured in five minute intervals at each catchment outlet. One catchment was built with GI vegetated swales on all parcels with the goal of intercepting, conveying, and infiltrating stormwater before it enters the sewer network. The remaining catchments were constructed with traditional gray infrastructure and “end-of-pipe” best management practices (BMPs) that treat stormwater before entering streams. This study compared characteristics of rainfall-runoff events at the green and gray infrastructure sites to understand their effects on suburban hydrology. The landscape GI strategy generally reduced rainfall-runoff ratios compared to gray infrastructure because of increased infiltration, ul

  2. Influence of rainfall and catchment characteristics on urban stormwater quality.

    Science.gov (United States)

    Liu, An; Egodawatta, Prasanna; Guan, Yuntao; Goonetilleke, Ashantha

    2013-02-01

    The accuracy and reliability of urban stormwater quality modelling outcomes are important for stormwater management decision making. The commonly adopted approach where only a limited number of factors are used to predict urban stormwater quality may not adequately represent the complexity of the quality response to a rainfall event or site-to-site differences to support efficient treatment design. This paper discusses an investigation into the influence of rainfall and catchment characteristics on urban stormwater quality in order to investigate the potential areas for errors in current stormwater quality modelling practices. It was found that the influence of rainfall characteristics on pollutant wash-off is step-wise based on specific thresholds. This means that a modelling approach where the wash-off process is predicted as a continuous function of rainfall intensity and duration is not appropriate. Additionally, other than conventional catchment characteristics, namely, land use and impervious surface fraction, other catchment characteristics such as impervious area layout, urban form and site specific characteristics have an important influence on both, pollutant build-up and wash-off processes. Finally, the use of solids as a surrogate to estimate other pollutant species was found to be inappropriate. Individually considering build-up and wash-off processes for each pollutant species should be the preferred option. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. 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.

  4. 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.

  5. Group NPDES stormwater permit application: The Conoco experience

    International Nuclear Information System (INIS)

    Holler, J.D.

    1993-01-01

    The US Environmental Protection Agency (USEPA) has reported that stormwater runoff is a major cause of pollution and use impairment to waters of the nation. Diffuse pollution sources (stormwater runoff) are increasingly important as controls for industrial process dischargers. On November 16, 1990 the Federal Clean Water Act National Pollutant Discharge Elimination System (NPDES) rules governing the discharge of stormwater were published (56 FR 40948). These rules potentially affect every type of business enterprise conducting work ''associated with industrial activity.'' Dischargers of stormwater associated with industrial activity ar required to either seek coverage under a federal or state general permit using notice of intent, apply for an individual permit, or apply for a permit through a two-part group application process. Conoco, Inc. Supply and Transportation (S and T) elected the latter alternative to attempt to comply with these new evolving complex, broad-ranging permitting requirements. This paper discusses specific details of S and T's strategy, BMP designs, data acquisition activities, monitoring results, as well as economic impacts on the corporation as a result of storm water permit requirements. S and T operates approximately 170 unique wholly and jointly owned petroleum product storage and transport facilities across the nation. Approximately one-third of these facilities were subject to stormwater permit application requirements

  6. Influence of governance structure on green stormwater infrastructure investment

    Science.gov (United States)

    Hopkins, Kristina G.; Grimm, Nancy B.; York, Abigail M.

    2018-01-01

    Communities are faced with the challenge of meeting regulatory requirements mandating reductions in water pollution from stormwater and combined sewer overflows (CSO). Green stormwater infrastructure and gray stormwater infrastructure are two types of water management strategies communities can use to address water pollution. In this study, we used long-term control plans from 25 U.S. cities to synthesize: the types of gray and green infrastructure being used by communities to address combined sewer overflows; the types of goals set; biophysical characteristics of each city; and factors associated with the governance of stormwater management. These city characteristics were then used to identify common characteristics of “green leader” cities—those that dedicated >20% of the control plan budget in green infrastructure. Five “green leader” cities were identified: Milwaukee, WI, Philadelphia, PA, Syracuse, NY, New York City, NY, and Buffalo, NY. These five cities had explicit green infrastructure goals targeting the volume of stormwater or percentage of impervious cover managed by green infrastructure. Results suggested that the management scale and complexity of the management system are less important factors than the ability to harness a “policy window” to integrate green infrastructure into control plans. Two case studies—Philadelphia, PA, and Milwaukee, WI—indicated that green leader cities have a long history of building momentum for green infrastructure through a series of phases from experimentation, demonstration, and finally—in the case of Philadelphia—a full transition in the approach used to manage CSOs.

  7. Factors Influencing Stormwater Mitigation in Permeable Pavement

    Directory of Open Access Journals (Sweden)

    Chun Yan Liu

    2017-12-01

    Full Text Available Permeable pavement (PP is used worldwide to mitigate surface runoff in urban areas. Various studies have examined the factors governing the hydrologic performance of PP. However, relatively little is known about the relative importance of these governing factors and the long-term hydrologic performance of PP. This study applied numerical models—calibrated and validated using existing experimental results—to simulate hundreds of event-based and two long-term rainfall scenarios for two designs of PP. Based on the event-based simulation results, rainfall intensity, rainfall volume, thickness of the storage layer and the hydraulic conductivity of the subgrade were identified as the most influential factors in PP runoff reduction. Over the long term, PP performed significantly better in a relatively drier climate (e.g., New York, reducing nearly 90% of runoff volume compared to 70% in a relatively wetter climate (e.g., Hong Kong. The two designs of PP examined performed differently, and the difference was more apparent in the relatively wetter climate. This study generated insights that will help the design and implementation of PP to mitigate stormwater worldwide.

  8. Enlightenment from ancient Chinese urban and rural stormwater management practices.

    Science.gov (United States)

    Wu, Che; Qiao, Mengxi; Wang, Sisi

    2013-01-01

    Hundreds of years ago, the ancient Chinese implemented several outstanding projects to cope with the changing climate and violent floods. Some of these projects are still in use today. These projects evolved from the experience and knowledge accumulated through the long coexistence of people with nature. The concepts behind these ancient stormwater management practices, such as low-impact development and sustainable drainage systems, are similar to the technology applied in modern stormwater management. This paper presents the cases of the Hani Terrace in Yunnan and the Fushou drainage system of Ganzhou in Jiangxi. The ancient Chinese knowledge behind these cases is seen in the design concepts and the features of these projects. These features help us to understand better their applications in the contemporary environment. In today's more complex environment, integrating traditional and advanced philosophy with modern technologies is extremely useful in building urban and rural stormwater management systems in China.

  9. Public health effects of inadequately managed stormwater runoff.

    Science.gov (United States)

    Gaffield, Stephen J; Goo, Robert L; Richards, Lynn A; Jackson, Richard J

    2003-09-01

    This study investigated the scale of the public health risk from stormwater runoff caused by urbanization. We compiled turbidity data for municipal treated drinking water as an indication of potential risk in selected US cities and compared estimated costs of waterborne disease and preventive measures. Turbidity levels in other US cities were similar to those linked to illnesses in Milwaukee, Wis, and Philadelphia, Pa. The estimated annual cost of waterborne illness is comparable to the long-term capital investment needed for improved drinking water treatment and stormwater management. Although additional data on cost and effectiveness are needed, stormwater management to minimize runoff and associated pollution appears to make sense for protecting public health at the least cost.

  10. 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.

  11. Environmental impacts of stormwater management and pollutant discharges

    DEFF Research Database (Denmark)

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

    in runoff are one possible source of (local) environmental impacts, the stormwater management system itself is a source of emissions. Raw material extraction, construction, operation, renewal, and disposal all cause environmental impacts at a more regional or even global scale. These impacts can...... be quantified using life cycle assessment, which on the other hand usually neglects the impacts from local emissions, even though these may potentially be significant. By integrating local emissions into the assessment, we are able to quantify the total environmental impacts of stormwater management solutions....... We have tested the approach using a sub-catchment of Copenhagen. The existing stormwater management system has to be adapted to climatic changes to maintain existing flood safety levels. The environmental impacts from both local and global emissions over a period of 100 years have been quantified...

  12. A game theory analysis of green infrastructure stormwater management policies

    Science.gov (United States)

    William, Reshmina; Garg, Jugal; Stillwell, Ashlynn S.

    2017-09-01

    Green stormwater infrastructure has been demonstrated as an innovative water resources management approach that addresses multiple challenges facing urban environments. However, there is little consensus on what policy strategies can be used to best incentivize green infrastructure adoption by private landowners. Game theory, an analysis framework that has historically been under-utilized within the context of stormwater management, is uniquely suited to address this policy question. We used a cooperative game theory framework to investigate the potential impacts of different policy strategies used to incentivize green infrastructure installation. The results indicate that municipal regulation leads to the greatest reduction in pollutant loading. However, the choice of the "best" regulatory approach will depend on a variety of different factors including politics and financial considerations. Large, downstream agents have a disproportionate share of bargaining power. Results also reveal that policy impacts are highly dependent on agents' spatial position within the stormwater network, leading to important questions of social equity and environmental justice.

  13. Using game theory to analyze green stormwater infrastructure implementation policies

    Science.gov (United States)

    William, R. K.; Garg, J.; Stillwell, A. S.

    2017-12-01

    While green stormwater infrastructure is a useful approach in addressing multiple challenges facing the urban environment, little consensus exists on how to best incentivize its adoption by private landowners. Game theory, a field of study designed to model conflict and cooperation between two or more agents, is well-suited to address this policy question. We used a cooperative game theory framework to analyze the impacts of three different policy approaches frequently used to incentivize the uptake of green infrastructure by private landowners: municipal regulation, direct grants, and stormwater fees. The results indicate that municipal regulation leads to the greatest environmental benefits; however, the choice of "best" regulatory approach is dependent on a variety of different factors including political and financial considerations. Policy impacts are also highly dependent on agents' spatial positions within the stormwater network. This finding leads to important questions of social equity and environmental justice.

  14. 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

  15. Removal of stormwater particulates by disc filter technology

    DEFF Research Database (Denmark)

    Nielsen, Katrine; Mikkelsen, Peter Steen; Eriksson, Eva

    The trend in the Danish society is toward disconnection of stormwater from the combined sewers and, where needed, local treatment using the best available technologies (BAT). The aim here was to assess a fast filtration technology for removal of particulate matter in stormwater with an emphasis...... and in the size-range of 100 nm. The physical treatment of particle filtration at 10 µm was inadequate to remove the small particles identified in this project. Coagulation with a cationic coagulant and subsequently flocculation is suggested as process improvements technologies....

  16. Social construction of stormwater control measures in Melbourne and Copenhagen:

    DEFF Research Database (Denmark)

    Madsen, Herle Mo; Brown, Rebekah; Elle, Morten

    2017-01-01

    Urban stormwater systems in cities around the world are challenged by urbanization and climate change, and a range of Stormwater Control Measures (SCMs) are being implemented as solutions to these challenges. We developed a conceptual framework of technological stabilization based on Social...... differences in their application due to different physical, organizational and cultural contexts in the two cities, drought being the main driver during the past decade in Melbourne (1997–2010) and pluvial flooding in Copenhagen (2007-). In Melbourne there is currently a strong integrated understanding...

  17. 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...... reaches), and non-structural BMPs, such as controls of chemicals or building materials, and street sweeping. The available knowledge of stormwater BMPs performance in pollution control is inconsistent and the effect of various BMPs on receiving water quality is either poorly understood, or not known...

  18. Removal of stormwater particulates by disc filter technology

    DEFF Research Database (Denmark)

    Nielsen, Katrine; Mikkelsen, Peter Steen; Eriksson, Eva

    The trend in the Danish society is toward disconnection of stormwater from the combined sewers and, where needed, local treatment using the best available technologies (BAT). The aim here was to assess a fast filtration technology for removal of particulate matter in stormwater with an emphasis...... on colloidal and nanosized particles. During the project period it rained 8.5 % of the time and the average daily rainfall was 2.9 mm/day. Based on three individual storm events it was found that 95 % of the particles were

  19. Characterisation and Treatment of Nano-sized Particles, Colloids and Associated Polycyclic Aromatic Hydrocarbons in Stormwater

    DEFF Research Database (Denmark)

    Nielsen, Katrine

    . The associated pollutants will, if not removed in stormwater treatment facilities, be discharged into receiving surface waters, due to enhanced transportation exerted by the colloids and nano-sized particles. More stormwater than previously is separated from wastewater and drained to stormwater treatment.......Since little is known about the colloids and nano-sized particle-enhanced transportation of pollutants in stormwater, it has been difficult to determine their quantitative role in the total release of pollutants into receiving waters.Therefore the main purpose of this thesis has been to document the presence...... and size distribution of colloids and nano-sized particles in stormwater, as well as quantify the particle-enhanced transportation of polycyclic aromatic hydrocarbons (PAHs) in stormwater. Stormwater from five sites in Europe was collected to characterise the particulate matter, colloids and nano...

  20. Sterilization of mentally retarded persons.

    Science.gov (United States)

    Van der Merwe, J V; Roux, J P

    1987-08-01

    South Africa's Abortion and Sterilization Act No 2 (1975) authorizes sterilization for severely retarded women provided the procedure is performed in a state hospital, certified by 2 medical practitioners (1 a psychiatrist), and the parent or guardian gives informed consent. Since 1975, 152 sterilizations (140 female, 12 male) have been performed under the provisions of this Act at Pretoria's H F Verwoerd Hospital. 92% of the patients were under 20 years of age. The majority were classified as profoundly or severely retarded (74) or moderately severely retarded (68). There were 20 patients with Down's syndrome and 22 with cerebral palsy. Hysterectomy was the method of choice in the 109 women in whom menstrual hygiene was a pertinent factor; the remaining 31 women were sterilized by tubal ligation. 98% of the parents or guardians of hysterectomy acceptors surveyed were satisfied with their decision and its outcome. Several indicated their daughter was more calm, cooperative, productive, and less irritable once relieved of her menstrual periods. A multidisciplinary team approach to the decision making process and the individualization of each case are essential to protect the rights of the mentally retarded. Factors such as the psychological trauma likely to result from pregnancy and childbirth, an inability to use contraception, and unsuitability to rear a child must be demonstrated. To ensure that legislation pertaining to the sterilization of the mentally retarded does not lead to abuse, inputs from the mental health professions are required.

  1. Using a geographic information system and hillslope runoff modeling to support decision-making for managed aquifer recharge using distributed stormwater collection

    Science.gov (United States)

    Teo, E. K.; Beganskas, S.; Young, K. S.; Weir, W. B.; Harmon, R. E.; Lozano, S.; Fisher, A. T.

    2017-12-01

    Many aquifer systems in central coastal California face a triple threat of excess demand, changing land use, and a shifting climate. These last two factors can contribute to reductions in groundwater recharge. Managed aquifer recharge using distributed stormwater collection (DSC-MAR) is an adaptation technique for collecting excess stormwater runoff from hillslopes for infiltration into underlying aquifers, before that water reaches a "blue line" stream. We are developing a decision support system (DSS) that combines surface and subsurface hydrogeological data with high-resolution predictions of hillslope runoff, with specific application to Santa Cruz and northern Monterey Counties. Other studies presented at AGU will focus on the northern and southern parts of our study region (San Lorenzo River Basin, Lower Pajaro River Basin). This presentation focuses on mid-Santa Cruz County, including the Soquel-Aptos Groundwater Basin. The DSS uses a geographic information system to compile and merge data from numerous local, state, and federal sources to identify locations on the landscape where DSC-MAR may be most suitable. This requires classification of disparate data types so that they can be combined. Stormwater runoff for individual river basins in the study region was simulated using historical streamflow data for calibration and validation. Both analyses were completed with relatively fine resolution, from 10 m2 pixels for elevation to 0.1-1.0 km hydrologic response units for properties such as soil and vegetation properties. Future climate is uncertain, so we used historical data to create a catalog of dry, normal, and wet hydrologic conditions, then created synthetic future climate scenarios for simulation. The DDS shows that there are numerous regions in mid-Santa Cruz County where there is a confluence of MAR suitability and the generation of stormwater runoff that could supply recharge projects (with a nominal target of 100 ac-ft/yr of infiltration), even

  2. Missing the link: urban stormwater quality and resident behaviour

    African Journals Online (AJOL)

    model described by Grimm et al. (2000) to develop a new per- spective on conventional urban stormwater and the social system in which it is embedded. The Urban Ecology model. The Urban Ecology model views societal and ecological patterns and processes as inherently linked (Grimm et al., 2000; Collins et al., 2011).

  3. Elemental Concentrations in Urban Green Stormwater Infrastructure Soils.

    Science.gov (United States)

    Kondo, Michelle C; Sharma, Raghav; Plante, Alain F; Yang, Yunwen; Burstyn, Igor

    2016-01-01

    Green stormwater infrastructure (GSI) is designed to capture stormwater for infiltration, detention, evapotranspiration, or reuse. Soils play a key role in stormwater interception at these facilities. It is important to assess whether contamination is occurring in GSI soils because urban stormwater drainage areas often accumulate elements of concern. Soil contamination could affect hydrologic and ecosystem functions. Maintenance workers and the public may also be exposed to GSI soils. We investigated soil elemental concentrations, categorized as macro- and micronutrients, heavy metals, and other elements, at 59 GSI sites in the city of Philadelphia. Non-GSI soil samples 3 to 5 m upland of GSI sites were used for comparison. We evaluated differences in elemental composition in GSI and non-GSI soils; the comparisons were corrected for the age of GSI facility, underlying soil type, street drainage, and surrounding land use. Concentrations of Ca and I were greater than background levels at GSI sites. Although GSI facilities appear to accumulate Ca and I, these elements do not pose a significant human health risk. Elements of concern to human health, including Cd, Hg, and Pb, were either no different or were lower in GSI soils compared with non-GSI soils. However, mean values found across GSI sites were up to four times greater than soil cleanup objectives for residential use. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. Some perspectives for environmental risk assessment of urban stormwater management

    DEFF Research Database (Denmark)

    Mikkelsen, Peter Steen; Baun, Anders; Ledin, Anna

    2002-01-01

    Introduction of new technologies for disposing stormwater locally, e.g. via infiltration into the ground, implies that the 'traditional' list of key-substances is not exhaustive and consequently, consultants and authorities have difficulties deciding whether to approve new technologies for stormw...

  5. Is stormwater harvesting beneficial to urban waterway environmental flows?

    Science.gov (United States)

    Fletcher, T D; Mitchell, V G; Deletic, A; Ladson, T R; Séven, A

    2007-01-01

    Urbanization degrades the hydrology and water quality of waterways. Changes to flow regimes include increased frequency of surface runoff, increased peak flows and an increase in total runoff. At the same time, water use in many cities is approaching, and in some cases exceeding, sustainable limits. Stormwater harvesting has the potential to mitigate a number of these detrimental impacts. However, excessive harvesting of stormwater could also be detrimental to stream health. Therefore, a study was undertaken to test whether typical stormwater harvesting scenarios could meet the dual objectives of (i) supplying urban water requirements, and (ii) restoring the flow regime as close as possible to 'natural' (pre-developed). Melbourne and Brisbane, which have different climates, were used along with three land use scenarios (low, medium and high density). Modelling was undertaken for a range of flow and water quality indicators. The results show that using these typical harvesting scenarios helped to bring flow and water quality back towards their pre-developed levels. In some cases, however, harvesting resulted in an over-extraction of flow, demonstrating the need for optimizing the harvesting strategy to meet both supply and environmental flow objectives. The results show that urban stormwater harvesting is a potential strategy for achieving both water conservation and environmental flows.

  6. Missing the link: urban stormwater quality and resident behaviour ...

    African Journals Online (AJOL)

    The implication is that most residents 'miss the link' – between their actions on land, their impacts on runoff and river water quality, and, in turn, their ability to influence societal patterns and processes. Keywords: stormwater drainage, social-ecological systems, environmental impacts, human behaviour, urban ecology ...

  7. Accuracy of a stormwater monitoring program for urban landuses.

    Science.gov (United States)

    Madarang, Krish; Kang, Joo-Hyon

    2013-09-01

    This study examined the accuracy of an urban stormwater monitoring program in estimating the annual discharge load (L(T)) and the annual reduction rate by a stormwater treatment device (R(T)) for total suspended solids. A calibrated stormwater management model was used to generate the entire stormwater runoff events in one year and was used to estimate L(T) and R(T) under different monitoring strategies having limited numbers of runoff events, including random, wet season, antecedent dry days (ADD)-based, monthly, and seasonally weighted. For random monitoring, 12 storms were required to estimate the values of L(T) and R(T) with mean relative errors of 13.98 and 0.24%, respectively. Monthly monitoring had slightly greater mean relative errors compared to random monitoring. Wet season and ADD-based monitoring under- or overestimated both L(T) and R(T). Monitoring with equal numbers of storms from the wet and dry seasons best estimated L(T) and R(T).

  8. National Stormwater Calculator - Version 1.1 (Model)

    Science.gov (United States)

    EPA’s National Stormwater Calculator (SWC) is a desktop application that estimates the annual amount of rainwater and frequency of runoff from a specific site anywhere in the United States (including Puerto Rico). The SWC estimates runoff at a site based on available information ...

  9. Stormwater management the American way: why no policy transfer?

    Directory of Open Access Journals (Sweden)

    David P. Dolowitz

    2015-09-01

    Full Text Available From the 1940s until the 1980s the federal government gradually extended its authority over the structure of the American stormwater management system. The goal was to improve the water quality of the nation’s waterways by regulating the pollution loads entering the system, primarily through the use of gray infrastructure. However during the1980s the Environmental Protection Agency (EPA began to explore new approaches toward the regulation of stormwater pollution. Instead of focusing only on gray mechanisms, the EPA began developing and promoting the use of low impact development (LID techniques as an element municipal governments could use to achieve their total maxim daily load of pollutants allowable under the National Pollutant Discharge Elimination System permit system. In light of the incentive offered by the EPA for the use of LID in the management of stormwater, it should be expected to provide a perfect area to observe policy transfer between federal, state and local governments; but it does not. This article will establish why the EPA began promoting a green approach to stormwater management and why this has not led to a widespread transfer of best management practices in the ways the literatures associated with federalism and policy transfer would suggest.

  10. STORMWATER TREATMENT USING MULTI-CHAMBERED TREATMENT TRAIN

    Science.gov (United States)

    slide presentation made at this conference. MCTT developed to abate toxicants in stormwater from critical source areas Pilot-scale reductions of > 90% for toxicity, Pb, Zn, certain organic toxicants SS & COD reduced 83% & 60%, respectively Full-scale tests substantiate...

  11. Simulated Benefits of Green Infrastructure for Urban Stormwater Management under Climate Change in Different Hydroclimatic and Archetypal Urban Settings

    Science.gov (United States)

    Johnson, T. E.; Butcher, J.; Sarkar, S.; Clark, C.

    2015-12-01

    Climate change could significantly alter the occurrence and management of urban stormwater runoff quantity and quality. Responding to this challenge requires an improved understanding of potential changes together with the effectiveness of management responses for reducing impacts under range of potential future climatic conditions. Traditional gray stormwater infrastructure generally uses single-purpose, hard structures including detention basins and storm sewers to dispose of rainwater. Green infrastructure (GI) uses vegetation and soil to manage rainwater where it falls. GI has been gaining in popularity, and has been shown to provide a number of benefits for adapting to climate change including effects on stormwater quantity, quality and carbon and nutrient biogeochemical cycling. Uncertainty remains, however, due to limited understanding of GI performance in different hydroclimatic and urban settings, and in response to changes in climate. In this study we use simulation modeling to assess the impacts of climate change on both gray (wet ponds) and green infrastructure practices (green roofs, swales, bioretention) in different hydroclimatic and urban settings. Simulations were conducted using RHESSYs, a mechanistic, hydrologic and biogeochemical model, for 36 characteristic urban "archetypes" (AUSs) representing different development patterns and GI practices found in typical U.S. cities. Climate change scenarios are based on dynamically and temporally downscaled, mid-21st century climate model output from the North American Regional Climate Change Assessment Program (NARCCAP). Results suggest altered mass and energy inputs will cause changes in performance of these practices for water quantity, water quality, and carbon sequestration that vary across the country. Infrastructure design should take these potential changes into consideration.

  12. Mathematical Modeling of Fate and Transport of Aqueous Species in Stormflow Entering Infiltration Basin.

    Science.gov (United States)

    Massoudieh, A.; Sengor, S. S.; Meyer, S.; Ginn, T. R.

    2004-12-01

    The State of California is evaluating the role of passive stormwater detention facilities for the purpose of attenuating potential dissolved and suspended chemical species that may originate in roadway runoff of rainfall. The engineering design of such infiltration basins requires tools to quantify their performance as recipients of stormwater runoff from roadways, and as filters of aqueous chemical species. For this purpose a one-dimensional unsaturated flow and transport model is developed to estimate the efficiency of storm-water infiltration basins in treating roadway generated metallic and organic pollutants. Kinematic wave approximation is used along with van Genuchten water retention model to simulate water percolation thorough the infiltration basin. For metals a Langmuir type nonlinear competitive sorption isotherm is used for transport of chemicals and a kinetic reversible linear sorption model is considered for organics. The model is applied to known roadway born metallic contaminations such as copper, zinc, lead, chromium, nickel and cadmium, as well as organic species such as diazinon, diuron, ghlyphosate and pyrene, for several representative soil and precipitation condition for California within a period of five years. Representative soil parameters and precipitation patterns are extracted from frequency distributions extracted from a recent study. In addition sensitivity analysis has been done to evaluate the effect of soil property values on the performance of infiltration basins. The results can be used to evaluate the performance of infiltration basins in improving the water quality as well as being used in providing guidelines in design and maintenance of infiltration basins.

  13. Urban stormwater source control policies: why and how?

    Science.gov (United States)

    Petrucci, G.; Deroubaix, J.-F.; Tassin, B.

    2014-09-01

    Stormwater source control is becoming a common strategy for urban stormwater management in many countries. It relies on regulations or other policy instruments compelling or inciting implementation, for each new urban development, of small-scale facilities to locally store and manage stormwater. Local authorities that pioneered source control since the 1980s have already observed that small-scale facilities systematically implemented over a catchment are able to influence its hydrological behaviour. This capability is the main strength of source control, as it allows compensation for the negative effects of urbanization. Yet, it also represents its main risk: if initial decision-making is not sufficiently accurate, source control can produce long-term negative effects. Because of its current spreading, source control will acquire an increasing role as a driver of hydrological changes in urban catchments, and the directions of these changes depend on current policy-making practices. This paper presents an analysis and a critical discussion of the main objectives that policy-makers attribute to stormwater source control. The investigation is based on a sample of French case studies, completed by a literature review for international comparison. It identifies four main objectives, some typical of urban stormwater management and some more innovative: flood reduction, receiving waters protection, sustainable development, costs reduction. The discussion focuses on how current policy-making practices are able to translate these objectives in concrete policy instruments, and on which knowledge and tools could improve this process. It is shown that for some objectives, basic knowledge is available, but the creation of policy instruments which are effective at the catchment scale and adapted to local conditions is still problematic. For other objectives, substantial lacks of knowledge exist, casting doubts on long-term effectiveness of current policy instruments. Research

  14. Urban stormwater source control policies: why and how?

    Directory of Open Access Journals (Sweden)

    G. Petrucci

    2014-09-01

    Full Text Available Stormwater source control is becoming a common strategy for urban stormwater management in many countries. It relies on regulations or other policy instruments compelling or inciting implementation, for each new urban development, of small-scale facilities to locally store and manage stormwater. Local authorities that pioneered source control since the 1980s have already observed that small-scale facilities systematically implemented over a catchment are able to influence its hydrological behaviour. This capability is the main strength of source control, as it allows compensation for the negative effects of urbanization. Yet, it also represents its main risk: if initial decision-making is not sufficiently accurate, source control can produce long-term negative effects. Because of its current spreading, source control will acquire an increasing role as a driver of hydrological changes in urban catchments, and the directions of these changes depend on current policy-making practices. This paper presents an analysis and a critical discussion of the main objectives that policy-makers attribute to stormwater source control. The investigation is based on a sample of French case studies, completed by a literature review for international comparison. It identifies four main objectives, some typical of urban stormwater management and some more innovative: flood reduction, receiving waters protection, sustainable development, costs reduction. The discussion focuses on how current policy-making practices are able to translate these objectives in concrete policy instruments, and on which knowledge and tools could improve this process. It is shown that for some objectives, basic knowledge is available, but the creation of policy instruments which are effective at the catchment scale and adapted to local conditions is still problematic. For other objectives, substantial lacks of knowledge exist, casting doubts on long-term effectiveness of current policy

  15. Controls on the chemical and isotopic compositions of urban stormwater in a semiarid zone

    Science.gov (United States)

    Asaf, L.; Nativ, R.; Shain, D.; Hassan, M.; Geyer, S.

    2004-07-01

    The temporal variations in the chemical and isotopic compositions of urban stormwater under different land uses, and their dependence on physical parameters such as precipitation intensity, stormwater discharge, cumulative stormwater volumes and the size of the drainage area, were investigated in the coastal city of Ashdod, Israel. During 2000/2001 and 2001/2002, 46 stormwater events were intensively monitored for precipitation distribution and intensity at three stations across the city, and for stormwater discharge at seven stations draining 85% of the city area. Sixty-eight and 202 precipitation samples were collected and analyzed for chemical and isotopic compositions, respectively, as were 186 stormwater samples, collected from the drains during 15 of the 46 events. Land use had only a minor effect on the concentrations of major ions and trace elements. Conversely, the concentrations and variety of volatile and semi-volatile organic compounds were significantly higher in stormwater generated in the industrial area than in that draining from residential areas. Ion and trace-metal concentrations were very low (below drinking-water standards) in 97% of the stormwater samples collected from all drains. Stormwater concentrations were higher at stations draining a larger area, thereby linking concentrations to the length of the stormwater flow paths. A first-flush effect was documented on both a seasonal and event basis for both ions and trace elements. The high concentrations of fecal coliform bacteria exceeded the drinking-water standards and displayed a random pattern. The isotopic ratios of oxygen and hydrogen in the stormwater suggest very little exposure to the atmosphere, resulting in very limited fractionation. The presence of fecal coliforms, ammonium in some samples, and specific ratios of oxygen and nitrogen isotopes, suggest that although the sewer and stormwater-collection systems are separated, wastewater, possibly from overflowing sewers, contributed

  16. COLOUR LEARNING IN RETARDED CHILDREN*

    African Journals Online (AJOL)

    Tt has been observed' that mentally retarded children have. :olour preferences, preferring, for example, to pick red and yellow sweets from a multicoloured supply. Among normal nursery-school children the same 2 colours feature in tests for preference, and it has been suggested' that it might be useful to utilize these ...

  17. Genetic Counseling in Mental Retardation.

    Science.gov (United States)

    Bowen, Peter

    The task of the genetic counselor who identifies genetic causes of mental retardation and assists families to understand risk of recurrence is described. Considered are chromosomal genetic disorders such as Down's syndrome, inherited disorders such as Tay-Sachs disease, identification by testing the amniotic fluid cells (amniocentresis) in time…

  18. Non-constant retardation coefficient

    International Nuclear Information System (INIS)

    Wang Zhiming; Gu Zhijie; Yang Yue'e; Li Shushen

    2004-12-01

    Retardation coefficient is one of the important parameters used in transport models describing radionuclide migration in geological media and usually regarded as a constant in the models. The objectives of the work are to understand: (1) Whether the retardation coefficient, R d , is a constant? (2) How much effect is R d on calculated consequence if R d is not constant? (3) Is the retardation coefficient derived from distribution coefficient, k d , according to conventional equation suitable for safety assessment? The objectives are achieved through test and analysis of the test results on radionuclide migration in unsaturated loess. It can be seen from the results that retardation coefficient, R d , of 85 Sr is not constant and increases with water content, θ, under unsaturated condition. R d , of 85 Sr derived from k d according to conventional equation can not be used for safety assessment. R d , used for safety assessment should be directly measured, rather than derived from k d . It is shown from calculation that the effect of R d on calculated consequence is very considerable. (authors)

  19. Flame Retardants Used in Flexible Polyurethane Foam

    Science.gov (United States)

    The partnership project on flame retardants in furniture seeks to update the health and environmental profiles of flame-retardant chemicals that meet fire safety standards for upholstered consumer products with polyurethane foam

  20. Mental Retardation and Parenting Stress

    Directory of Open Access Journals (Sweden)

    Eleni Siamaga

    2011-01-01

    Full Text Available Backround: The presence, upbringing and looking after of a mentally retarded child in the family, can become a threat to the mental health of its parents and is the main predisposing factor of stress for the parents.Aim: The purpose of this systematic review is (a to document the contemporary research bibliography related to the stress of parents with mentally retarded children, (b to aggregate the factors and secondary parameters based on the contemporary research related to the influence of the (child’s mental retardation on the parents and (c to show an intercultural aspect regarding the presence of stress to parents with mentally retarded children.Methods: Systematic review of research articles published in scientific journals included in the international academic databases HEAL-LING, SAGE, ELSEVIER, WILSON, SCIENCEDIRECT, MEDLINE, PUBMED, PsycINFO, Cochrane, EMBASE, SCIRUS and CINAHL having as search criteria and key words the terms («parental stress and mental retardation» [MeSH], «parenting stress and persons with special needs» [MeSH], «mental retardation and family problems» [MeSH], «stress and parents» [MeSH], «parenting and stress» [MeSH], «mental delay and parents» [MeSH], «developmental disabilities and family stress» [MeSH], «intellectual handicap and parenting» [MeSH], «maternal stress and child with disabilities» [MeSH].Discussion: The review has proven that all forms of mental retardation have an important -from a statistic point of viewimpacton the parents’ mental health. Anxiety, stress and depression are common symptoms mentioned by the parents.Additionally, there are individual variables such as the husband-wife relationship, the parents’ approach to their child’s disability, the parental strategies used in order to cope with the daily life of the child’s disability and the behavioural problems of their child, all of which contribute to the increase of the level of parental stress

  1. People with Mental Retardation Are Dying, Legally.

    Science.gov (United States)

    Keyes, Denis; And Others

    1997-01-01

    Criticizes the institution of the death penalty for convicted criminals with mental retardation. Examples are given of cases in which juries were not told of the defendant's mental retardation before sentencing, and a list of defendants with mental retardation that have been executed since 1976 is provided. (CR)

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

    DEFF Research Database (Denmark)

    Birch, Heidi

    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...... the right treatment level to protect surface waters. Stormwater runoff is very dynamic both quality and quantity wise. In order to optimize the sampling of such phenomena, advanced sampling equipment is required. Such equipment is expensive, and furthermore, it is time consuming to conduct the sampling...

  3. Stormwater quality management in rail transportation--past, present and future.

    Science.gov (United States)

    Vo, Phuong Tram; Ngo, Huu Hao; Guo, Wenshan; Zhou, John L; Listowski, Andrzej; Du, Bin; Wei, Qin; Bui, Xuan Thanh

    2015-04-15

    Railways currently play an important role in sustainable transportation systems, owing to their substantial carrying capacity, environmental friendliness and land-saving advantages. Although total pollutant emissions from railway systems are far less than that of automobile vehicles, the pollution from railway operations should not be underestimated. To date, both scientific and practical papers dealing with stormwater management for rail tracks have solely focused on its drainage function. Unlike roadway transport, the potential of stormwater pollution from railway operations is currently mishandled. There have been very few studies into the impact of its operations on water quality. Hence, upon the realisation on the significance of nonpoint source pollution, stormwater management priorities should have been re-evaluated. This paper provides an examination of past and current practices of stormwater management in the railway industry, potential sources of stormwater pollution, obstacles faced in stormwater management and concludes with strategies for future management directions. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Methodology of sensitive planning and design of stormwater drainage system on urban watersheds

    Directory of Open Access Journals (Sweden)

    Milićević Dragan B.

    2017-01-01

    Full Text Available For sustainable stormwater management planning in urban areas a hierarchical approach is needed, from planning on the watershed level, to the implementation on the location level, so a comprehensive approach to planning and designing the improvement of stormwater drainage could be provided with a goal of developing a drainage system, which balances the goals of drainage efficiency maximization and minimizing the negative effects on the environment. But the watershed level, which is relevant to urban hydrology, is almost always ignored while developing stormwater management plans. This paper shows a methodology oriented towards studying of the morphology of the urban watershed in the context of sustainable stormwater management, which consist of five steps and intends to help city planners and engineers choose the right location and make a selection of the best stormwater management practices when defining a sustainable decentralized stormwater management plan.

  5. Stormwater management: adaptation and planning under climate change

    International Nuclear Information System (INIS)

    Mailhot, A.

    2009-01-01

    'Full text:' Extreme rainfall events are expected to increase in intensity and frequency in a future climate. Such a change will have an impact on the level of service provided by stormwater infrastructures since the current capacity is based on statistical analyses of past events, assuming that past conditions are representative of future climate conditions. Therefore, an increase in the intensity and frequency of extreme events will result in increasing runoff volumes and peak discharges that will more frequently exceed the capacity of current systems. For that reason, it is important to look for adaptation measures and to review design criteria in order to maintain an acceptable level of service in the long term. One important challenge related to stormwater management and climate change (CC) is related to the time scale of both the expected lifespan of some system components (that can last up to 100 years) and the horizon of the actual CC projection (50 to 100 years). Pipes currently replaced or installed may consequently experience very different climatic conditions during their lifetime and a general degradation of the level of service may be expected according to the actual CC projections. Among others, this means that the design criteria currently used must be reviewed. This paper intends to review and describe the main issues related to adaptation and planning of stormwater management infrastructures under climate change. More precisely, the following topics will be presented and discussed: 1) what are the available projections for intense rainfall events and what are the main uncertainties related to these projections? (how reliable are they?); 2) what will be the impacts of CC on stormwater management according to available projections? 3) how do we revise design criteria in a changing climate and define the level of service in a context where the return period concept is no longer valid? 4) what kind of adaptation measures can be put forward

  6. 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

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

    DEFF Research Database (Denmark)

    Vezzaro, Luca

    The increasing focus on management of stormwater Priority Pollutants (PP) enhances the role of mathematical models as support for the assessment of stormwater quality control strategies. This thesis investigates and presents modelling approaches that are suitable to simulate PP fluxes across stor...... for management of stormwater pollution. Examples in the thesis are focused on heavy metals (Cu, Zn) and selected organic substances (DEHP, Gliphosate, Pyrene, IPBC, Benzene....

  8. Modeling Tool to Quantify Metal Sources in Stormwater Discharges at Naval Facilities (NESDI Project 455)

    Science.gov (United States)

    2014-06-01

    demonstration/validation project to assess the use of the urban stormwater model Windows Source Loading and Management Model (WinSLAMM) to characterize...the urban stormwater model Windows Source Loading and Management Model (WinSlamm) to characterize sources of copper and zinc in storm runoff at Navy...are ubiquitous contaminants found in stormwater discharges in urban and industrialized areas. These contaminants originate from a variety of sources

  9. Characterizing heavy metal build-up on urban road surfaces: Implication for stormwater reuse

    Energy Technology Data Exchange (ETDEWEB)

    Liu, An [Research Centre of Environmental Engineering and Management, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen (China); Cooperative Research and Education Centre for Environmental Technology, Kyoto University–Tsinghua University, 518055 Shenzhen (China); Liu, Liang; Li, Dunzhu [Research Centre of Environmental Engineering and Management, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen (China); Guan, Yuntao, E-mail: guanyt@tsinghua.edu.cn [Research Centre of Environmental Engineering and Management, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen (China); School of Environment, Tsinghua University, Beijing 100084 (China)

    2015-05-15

    Stormwater reuse is increasingly popular in the worldwide. In terms of urban road stormwater, it commonly contains toxic pollutants such as heavy metals, which could undermine the reuse safety. The research study investigated heavy metal build-up characteristics on urban roads in a typical megacity of South China. The research outcomes show the high variability in heavy metal build-up loads among different urban road sites. The degree of traffic congestion and road surface roughness was found to exert a more significant influence on heavy metal build-up rather than traffic volume. Due to relatively higher heavy metal loads, stormwater from roads with more congested traffic conditions or rougher surfaces might be suitable for low-water-quality required activities while the stormwater from by-pass road sections could be appropriate for relatively high-water-quality required purposes since the stormwater could be relatively less polluted. Based on the research outcomes, a decision-making process for heavy metals based urban road stormwater reuse was proposed. The new finding highlights the importance to undertaking a “fit-for-purpose” road stormwater reuse strategy. Additionally, the research results can also contribute to enhancing stormwater reuse safety. - Highlights: • Heavy metal (HM) build-up varies with traffic and road surface conditions. • Traffic congestion and surface roughness exert a higher impact on HM build-up. • A “fit-for-purpose” strategy could suit urban road stormwater reuse.

  10. Effects of urban stormwater-management strategies on stream-water quantity and quality

    Science.gov (United States)

    Loperfido, J.V.; Hogan, Dianna M.

    2012-01-01

    Urbanization results in elevated stormwater runoff, greater and more intense streamflow, and increased delivery of pollutants to local streams and downstream aquatic systems such as the Chesapeake Bay. Stormwater Best Management Practices (BMPs) are used to mitigate these effects of urban land use by retaining large volumes of stormwater runoff (water quantity) and removing pollutants in the runoff (water quality). Current USGS research aims to understand how the spatial pattern and connectivity of stormwater BMPs affect water quantity and water quality in urban areas.

  11. 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 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...

  12. 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...

  13. Characterizing heavy metal build-up on urban road surfaces: Implication for stormwater reuse

    International Nuclear Information System (INIS)

    Liu, An; Liu, Liang; Li, Dunzhu; Guan, Yuntao

    2015-01-01

    Stormwater reuse is increasingly popular in the worldwide. In terms of urban road stormwater, it commonly contains toxic pollutants such as heavy metals, which could undermine the reuse safety. The research study investigated heavy metal build-up characteristics on urban roads in a typical megacity of South China. The research outcomes show the high variability in heavy metal build-up loads among different urban road sites. The degree of traffic congestion and road surface roughness was found to exert a more significant influence on heavy metal build-up rather than traffic volume. Due to relatively higher heavy metal loads, stormwater from roads with more congested traffic conditions or rougher surfaces might be suitable for low-water-quality required activities while the stormwater from by-pass road sections could be appropriate for relatively high-water-quality required purposes since the stormwater could be relatively less polluted. Based on the research outcomes, a decision-making process for heavy metals based urban road stormwater reuse was proposed. The new finding highlights the importance to undertaking a “fit-for-purpose” road stormwater reuse strategy. Additionally, the research results can also contribute to enhancing stormwater reuse safety. - Highlights: • Heavy metal (HM) build-up varies with traffic and road surface conditions. • Traffic congestion and surface roughness exert a higher impact on HM build-up. • A “fit-for-purpose” strategy could suit urban road stormwater reuse

  14. Parental Attitude Towards Mental Retardation

    Directory of Open Access Journals (Sweden)

    LEOKADIA WIATROWSKA

    2017-10-01

    Full Text Available https://doaj.org/puChild's developmental retardation is an undoubted condition for the absence of educational attainment and its unpleasant mental state. Due to the nature of multidimensional state of that, parental attitudes become relevant, as they affect the acceleration or retardation of development. Positive parental attitudes are the strong weapon for the child and his struggles on the way to an equal start and equal development opportunities. For this reason you should emphasize those factors that build the structures supporting developmental progression.An ecosystem approach to human development emphasizes each factor as relevant component for growth and expansion, without denying its own human activity and his self-determination rightblisher/metadata

  15. 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.

  16. [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.

  17. Hydrologic data for urban stormwater studies in the Dallas-Fort Worth area, Texas, 1992-94

    Science.gov (United States)

    Baldys, Stanley; Raines, T.H.; Mansfield, B.L.; Sandlin, J.T.

    1997-01-01

    This report presents precipitation and waterquality data from analyses of 210 samples collected at 30 storm-sewer outfall stations in the Dallas-Fort Worth area, Texas, during February 1992-November 1994. The data were collected to fulfill requirements mandated by the U.S. Environmental Protection Agency to the cities of Arlington, Dallas, Fort Worth, Garland, Irving, Mesquite, and Piano and to the Dallas and Fort Worth Districts of the Texas Department of Transportation to obtain a National Pollution Discharge Elimination System permit. Data were collected at storm-sewer outfall stations in drainage basins classified as singular land use, either residential, commercial, industrial, or highway. Also included are qualityassurance/quality-control data for samples collected in conjunction with the stormwater samples.

  18. Is there a specific geochemical signature of urban soils dedicated to stormwater infiltration?

    Science.gov (United States)

    Delolme, Cécile; Poulenard, Jérôme; Dorioz, Jean-Marcel; Bedell, Jean-Philippe; Winiarski, Thierry

    2014-05-01

    Stormwater infiltration devices are widely used in urban areas to recharge aquifers. They consequently store and concentrate on small surfaces, suspended particles coming from the erosion of the urban watershed carried out by stormwater are deposited at the surface of the receiving soil. This leads to a sedimentary layer that could be considered as a technosol where pedogenesis is occurring in relation with the receiving underlying soil. The knowledge related to these specific soils comes from a very small number of urban catchment. Moreover, few data are available concerning their main agronomic characteristics and the presence of others contaminants related to urban, industrial or agricultural activities. Our objective was to see if there is a generic specific geochemical signature that could characterize these technosols or if it is mostly explained by the catchment characteristics. For the first time, the surface soil of 19 infiltration basins situated in the East of Lyon were sampled in spring 2012 and chosen to represent a diversity of urban catchment typology. A mean representative surface layer sample was obtained with a mixture of 8 to 20 subsamples (depending on the basin surface) collected randomly on each basin. Numerous geochemical parameters were measured : pH, Total Organic Matter, Total Organic Carbon, carbonate content, texture, visible and infra-red spectra, phosphorus speciation, total nitrogen, total Zn, Cu, Ni, Cd, Pb, Cr, 7 pesticides, 16 PAHs, sum of 17 Dioxines, sum of the 7 indicator PCB, alkylphenols. A first analysis of the results underlines the great variability of the different parameters due to the diversity of management and design of basins. Nevertheless a stable chemical "signature" can be precised in relation to the concomitant presence of componants in rather stable proportions. We confirm that these specific urban soils are highly organic (4 to 20% dry weight) with high total PAHs and heavy metals contents with a silty texture

  19. Final report on a cold climate permeable interlocking concrete pavement test facility at the University of New Hampshire Stormwater Center.

    Science.gov (United States)

    2013-05-01

    University of New Hampshire Stormwater Center (UNHSC) completed a two year field verification study of a permeable interlocking concrete pavement (PICP) stormwater management system. The purpose of this study was to evaluate the cold climate function...

  20. Assessing the effectiveness of green infrastructure stormwater best management practices in New England at the small watershed scale.

    Science.gov (United States)

    Methods are needed to evaluate the effectiveness of existing Stormwater Best Management Practices (BMPs) and Low Impact Development and to predict the relative effectiveness of proposed stormwater management plans in maintaining the habitat and biotic integrity of streams in New ...

  1. Assessment of copper removal from highway stormwater runoff using Apatite II(TM) and compost : laboratory and field testing.

    Science.gov (United States)

    2015-03-01

    -Stormwater runoff introduces heavy metals to surface waters that are harmful to aquatic organisms, : including endangered salmon. This work evaluates Apatite II, a biogenic fish bone based adsorbent, for removing metal : from stormwater. The meta...

  2. Valuing environmental services provided by local stormwater management

    Science.gov (United States)

    Brent, Daniel A.; Gangadharan, Lata; Lassiter, Allison; Leroux, Anke; Raschky, Paul A.

    2017-06-01

    The management of stormwater runoff via distributed green infrastructures delivers a number of environmental services that go beyond the reduction of flood risk, which has been the focus of conventional stormwater systems. Not all of these services may be equally valued by the public, however. This paper estimates households' willingness to pay (WTP) for improvements in water security, stream health, recreational and amenity values, as well as reduction in flood risk and urban heat island effect. We use data from nearly 1000 personal interviews with residential homeowners in Melbourne and Sydney, Australia. Our results suggest that the WTP for the highest levels of all environmental services is A799 per household per year. WTP is mainly driven by residents valuing improvements in local stream health, exemptions in water restrictions, the prevention of flash flooding, and decreased peak urban temperatures respectively at A297, A244, A104 and A$65 per year. We further conduct a benefit transfer analysis and find that the WTP and compensating surplus are not significantly different between the study areas. Our findings provide additional support that stormwater management via green infrastructures have large nonmarket benefits and that, under certain conditions, benefit values can be transferred to different locations.

  3. Implementation of reactive and predictive real-time control strategies to optimize dry stormwater detention ponds

    Science.gov (United States)

    Gaborit, Étienne; Anctil, François; Vanrolleghem, Peter A.; Pelletier, Geneviève

    2013-04-01

    here increased the pond's TSS (and associated pollution) removal efficiency from 46% (current state) to between 70 and 90%, depending on the pond's capacity considered. The RTC strategies allow simultaneously maximizing the detention time of water, while minimizing the hydraulic shocks induced to the receiving water bodies and preventing overflow. A constraint relative to a maximum time of 4 days with water accumulated in the pond was thus respected to avoid mosquito breeding issues. The predictive control schemes (taking rainfall forecasts into consideration) can further reinforce the safety of the management strategies, even if meteorological forecasts are, of course, not error-free. With RTC, the studied pond capacity could thus have been limited to 1250 m3 instead of the 4000 m3 capacity currently used under static control. References Marsalek, J. 2005. Evolution of urban drainage: from cloaca maxima to environmental sustainability. Paper presented at Acqua e Citta, I Convegno Nazionale di Idraulica Urbana, Cent. Stud. Idraul. Urbana, Sant'Agnello di Sorrento, Italy, 28- 30 Sept. Middleton, J.R. and Barrett, M.E. 2008. Water quality performance of a batch-type stormwater detention basin. Water Environment Research, 80 (2): 172-178. Doi: http://dx.doi.org/10.2175/106143007X220842 Muschalla, D., Pelletier, G., Berrouard, É., Carpenter, J.-F., Vallet, B., and Vanrolleghem, P.A. 2009. Ecohydraulic-driven real-time control of stormwater basins. In: Proceedings 8th International Conference on Urban Drainage Modelling (8UDM), Tokyo, Japan, September 7-11. National Research Council, 1993. Managing Wastewater in Coastal Urban Areas. Washington, DC: National Academy Press. Shammaa, Y., Zhu, D.Z., Gyürék, L.L., and Labatiuk C.W. 2002. Effectiveness of dry ponds for stormwater total suspended solids removal. Canadian Journal of Civil Engineering, 29 (2): 316-324 (9). Doi: 10.1139/l02-008

  4. Water Quality of Combined Sewer Overflows, Stormwater, and Streams, Omaha, Nebraska, 2006-07

    Science.gov (United States)

    Vogel, Jason R.; Frankforter, Jill D.; Rus, David L.; Hobza, Christopher M.; Moser, Matthew T.

    2009-01-01

    The U.S. Geological Survey, in cooperation with the City of Omaha, investigated the water quality of combined sewer overflows, stormwater, and streams in the Omaha, Nebraska, area by collecting and analyzing 1,175 water samples from August 2006 through October 2007. The study area included the drainage area of Papillion Creek at Capeheart Road near Bellevue, Nebraska, which encompasses the tributary drainages of the Big and Little Papillion Creeks and Cole Creek, along with the Missouri River reach that is adjacent to Omaha. Of the 101 constituents analyzed during the study, 100 were detected in at least 1 sample during the study. Spatial and seasonal comparisons were completed for environmental samples. Measured concentrations in stream samples were compared to water-quality criteria for pollutants of concern. Finally, the mass loads of water-quality constituents in the combined sewer overflow discharges, stormwater outfalls, and streams were computed and compared. The results of the study indicate that combined sewer overflow and stormwater discharges are affecting the water quality of the streams in the Omaha area. At the Papillion Creek Basin sites, Escherichia coli densities were greater than 126 units per 100 milliliters in 99 percent of the samples (212 of 213 samples analyzed for Escherichia coli) collected during the recreational-use season from May through September (in 2006 and 2007). Escherichia coli densities in 76 percent of Missouri River samples (39 of 51 samples) were greater than 126 units per 100 milliliters in samples collected from May through September (in 2006 and 2007). None of the constituents with human health criteria for consumption of water, fish, and other aquatic organisms were detected at levels greater than the criteria in any of the samples collected during this study. Total phosphorus concentrations in water samples collected in the Papillion Creek Basin were in excess of the U.S. Environmental Protection Agency's proposed

  5. Ocular disorder in children with mental retardation.

    Science.gov (United States)

    Joshi, Rajesh Subhash; Somani, Abhishek Arun Kumar

    2013-04-01

    Ocular problems are common in mentally retarded children. Due to population growth these problems are increasing. Prevalence rate is variable from region to region. Data on ocular problems in mentally retarded school children is lacking in this region. The aim of the present study was to identify the ocular disorders in children with mental retardation attending special schools in a district and to study their relationship with the degree of retardation. A total of 241 mentally retarded school children in the age group of 6-16 years attending special schools for the mentally retarded children in a district in central India were examined by a team of ophthalmologist, psychiatrist, and a resident in ophthalmology department of a medical college. Complete ocular examination was done. Ocular problems were identified and categorized according to the intelligent quotient. One hundred and twenty four children (51.45%) had ocular problems. Strabismus (10.37%) and refractive error (20.75%) were the common ocular problems seen in this study. An association was found between the severity of mental retardation and ocular problems (P<0.005). However, no association was seen between the severity of mental retardation and strabismus and refractive error. A high prevalence of ocular problems was seen in mentally retarded school children. Children with mental retardation should undergo annual ophthalmological check up. Early detection and correction of ocular problems will prevent visual impairment in future.

  6. 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

    Danish municipalities work towards separating stormwater and sewage. But stormwater runoff may be heavily polluted and therefore it is needed to find Best Available Technologies (BAT) to source separate and treat stormwater before discharge into surface waters. The aim here was to determine...

  7. NATIONAL STORMWATER CALCULATOR USER’S GUIDE – VERSION 1.1

    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 historica...

  8. NATIONAL STORMWATER CALCULATOR USER’S GUIDE – VERSION 1.2

    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 historica...

  9. 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...

  10. TRADING ALLOWANCES FOR STORMWATER CONTROL: ACCOUNTING FOR CONTINUOUS HYDROLOGY AND OPPORTUNITY COSTS

    Science.gov (United States)

    Excess stormwater runoff is a serious problem in a large number of urban areas, causing flooding, water pollution, groundwater recharge deficits and ecological damage to urban streams. It has been posited that to mitigate the effects of excess stormwater runoff, policy makers cou...

  11. TREATMENT OF HEAVY METALS IN STORMWATER RUNOFF USING WET POND AND WETLAND MESOCOSMS

    Science.gov (United States)

    Urban stormwater runoff is being recognized as a major source of pollutants to receiving waters and a number of recent investigations have evaluated stormwater runoff quality and best management practices to minimize pollutant input to receiving waters. Particle-bound contaminant...

  12. Charging for stormwater in South Africa | Fisher-Jeffes | Water SA

    African Journals Online (AJOL)

    Municipalities across South Africa charge their citizens for potable water and sewerage. Stormwater management, however, is generally funded through municipal rates. Competition with other pressing needs frequently results in the stormwater departments being significantly under-funded – at times only receiving a tenth ...

  13. Coupling distributed stormwater collection and managed aquifer recharge: Field application and implications.

    Science.gov (United States)

    Beganskas, S; Fisher, A T

    2017-09-15

    Groundwater is increasingly important for satisfying California's growing fresh water demand. Strategies like managed aquifer recharge (MAR) can improve groundwater supplies, mitigating the negative consequences of persistent groundwater overdraft. Distributed stormwater collection (DSC)-MAR projects collect and infiltrate excess hillslope runoff before it reaches a stream, focusing on 40-400 ha drainage areas (100-1000 ac). We present results from six years of DSC-MAR operation-including high resolution analyses of precipitation, runoff generation, infiltration, and sediment transport-and discuss their implications for regional resource management. This project generated significant water supply benefit over six years, including an extended regional drought, collecting and infiltrating 5.3 × 10 5  m 3 (426 ac-ft). Runoff generation was highly sensitive to sub-daily storm frequency, duration, and intensity, and a single intense storm often accounted for a large fraction of annual runoff. Observed infiltration rates varied widely in space and time. The basin-average infiltration rate during storms was 1-3 m/d, with point-specific rates up to 8 m/d. Despite efforts to limit sediment load, 8.2 × 10 5  kg of fine-grained sediment accumulated in the infiltration basin over three years, likely reducing soil infiltration capacity. Periodic removal of accumulated material, better source control, and/or improved sediment detention could mitigate this effect in the future. Regional soil analyses can maximize DSC-MAR benefits by identifying high-infiltration capacity features and characterizing upland sediment sources. A regional network of DSC-MAR projects could increase groundwater supplies while contributing to improved groundwater quality, flood mitigation, and stakeholder engagement. Copyright © 2017 Elsevier Ltd. All rights reserved.

  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......Micropollutant monitoring in stormwater discharges is challenging because of the diversity of sources and thus large number of pollutants found in stormwater. This is further complicated by the dynamics in runoff flows and the large number of discharge points. Most passive samplers are non...... 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. Behaviour change: Trialling a novel approach to reduce industrial stormwater pollution.

    Science.gov (United States)

    Boulet, M; Ghafoori, E; Jorgensen, B S; Smith, L D G

    2017-12-15

    The evidence base for the performance and effectiveness of non-structural measures to manage stormwater pollution in industrial areas is relatively underdeveloped, despite their increased use in practice. This study aims to advance stormwater management practice and research by presenting a detailed case study of the development, implementation and evaluation of a targeted behaviour change trial that engaged small to medium industrial businesses in stormwater pollution prevention. Utilising a combination of different behaviour change strategies - including capacity building, social norms and commitment - a number of preventative stormwater pollution behaviours were changed in participating businesses. Our study provides a practice model for tackling stormwater pollution from a behavioural perspective that can be further developed by both practitioners and researchers to create effective and long-lasting change. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Sorption media for stormwater treatment - A laboratory evaluation of five low-cost media for their ability to remove metals and phosphorus from artificial stormwater

    DEFF Research Database (Denmark)

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

    2012-01-01

    states. The sorbents were tested towards phosphorus, arsenic, cadmium, chromium, copper, nickel, lead and zinc at concentration and conditions relevant for typical stormwater. The materials were tested for sorption capacity and kinetics. Desorption was tested under neutral and alkaline conditions...

  17. Stormwater management network effectiveness and implications for urban watershed function: A critical review

    Science.gov (United States)

    Jefferson, Anne J.; Bhaskar, Aditi S.; Hopkins, Kristina G.; Fanelli, Rosemary; Avellaneda, Pedro M.; McMillan, Sara K.

    2017-01-01

    Deleterious effects of urban stormwater are widely recognized. In several countries, regulations have been put into place to improve the conditions of receiving water bodies, but planning and engineering of stormwater control is typically carried out at smaller scales. Quantifying cumulative effectiveness of many stormwater control measures on a watershed scale is critical to understanding how small-scale practices translate to urban river health. We review 100 empirical and modelling studies of stormwater management effectiveness at the watershed scale in diverse physiographic settings. Effects of networks with stormwater control measures (SCMs) that promote infiltration and harvest have been more intensively studied than have detention-based SCM networks. Studies of peak flows and flow volumes are common, whereas baseflow, groundwater recharge, and evapotranspiration have received comparatively little attention. Export of nutrients and suspended sediments have been the primary water quality focus in the United States, whereas metals, particularly those associated with sediments, have received greater attention in Europe and Australia. Often, quantifying cumulative effects of stormwater management is complicated by needing to separate its signal from the signal of urbanization itself, innate watershed characteristics that lead to a range of hydrologic and water quality responses, and the varying functions of multiple types of SCMs. Biases in geographic distribution of study areas, and size and impervious surface cover of watersheds studied also limit our understanding of responses. We propose hysteretic trajectories for how watershed function responds to increasing imperviousness and stormwater management. Even where impervious area is treated with SCMs, watershed function may not be restored to its predevelopment condition because of the lack of treatment of all stormwater generated from impervious surfaces; non-additive effects of individual SCMs; and

  18. Familial mental retardation: a continuing dilemma.

    Science.gov (United States)

    Zigler, E

    1967-01-20

    The heterogeneous nature of mental retardation, as well as certain common practices of workers in the area, has resulted in a variety of conceptual am biguities. Considerable order could be brought to the area if, instead of viewing all retardates as a homogeneous group arbitrarily defined by some I.Q. score, workers would clearly distinguish between the group of retardates known to suffer from some organic defect and the larger group of retardates referred to as familial retardates. It is the etiology of familial retardation that currently constitutes the greatest mystery. A number of authorities have emphasized the need for employing recent polygenic models of inheritance in an effort to understand the familial retardate. While appreciating the importance of environment in affecting the distribution determined by genetic inheritance, these workers have argued that familial retardates are not essentially different from individuals of greater intellect, but represent, rather, the lower portion of the intellectual curve which reflects normal intellectual variability. As emphasized by the two-group approach, retardates with known physiological or organic defect are viewed as presenting a quite different etiological problem. The familial retardate, on the other hand, is seen as a perfectly normal expression of the population gene pool, of slower and more limited intellectual development than the individual of average intellect. This view generates the proposition that retardates and normals at the same general cognitive level-that is, of the same mental age-are similar in respect to their cognitive functioning. However, such a proposition runs headlong into findings that retardates and normals of the same mental age often differ in performance. Such findings have bolstered what is currently the most popular theoretical approach to retarded functioning-namely, the view that all retardates suffer from some specific defect which inheres in mental retardation and thus

  19. Potential effects of structural controls and street sweeping on stormwater loads to the lower Charles River, Massachusetts

    Science.gov (United States)

    Zarriello, Phillip J.; Breault, Robert F.; Weiskel, Peter K.

    2002-01-01

    The water quality of the lower Charles River is periodically impaired by combined sewer overflows (CSOs) and non-CSO stormwater runoff. This study examined the potential non-CSO load reductions of suspended solids, fecal coliform bacteria, total phosphorus, and total lead that could reasonably be achieved by implementation of stormwater best management practices, including both structural controls and systematic street sweeping. Structural controls were grouped by major physical or chemical process; these included infiltration-filtration (physical separation), biofiltration-bioretention (biological mechanisms), or detention-retention (physical settling). For each of these categories, upper and lower quartiles, median, and average removal efficiencies were compiled from three national databases of structural control performance. Removal efficiencies obtained indicated a wide range of performance. Removal was generally greatest for infiltration-filtration controls and suspended solids, and least for biofiltration-bioretention controls and fecal coliform bacteria. Street sweeping has received renewed interest as a water-quality control practice because of reported improvements in sweeper technology and the recognition that opportunities for implementing structural controls are limited in highly urbanized areas. The Stormwater Management Model that was developed by the U.S. Geological Survey for the lower Charles River Watershed was modified to simulate the effects of street sweeping in a single-family land-use basin. Constituent buildup and washoff variable values were calibrated to observed annual and storm-event loads. Once calibrated, the street sweeping model was applied to various permutations of four sweeper efficiencies and six sweeping frequencies that ranged from every day to once every 30 days. Reduction of constituent loads to the lower Charles River by the combined hypothetical practices of structural controls and street sweeping was estimated for a range

  20. Validation of stormwater biofilters using in-situ columns.

    Science.gov (United States)

    Zhang, Kefeng; Valognes, Valentin; Page, Declan; Deletic, Ana; McCarthy, David

    2016-02-15

    Stormwater harvesting biofilters need to be validated if the treatment is to be relied upon. Currently, full-scale challenge tests (FCTs), performed in the field, are required for their validation. This is impractical for stormwater biofilters because of their size and flow capacity. Hence, for these natural treatment systems, new tools are required as alternatives to FCT. This study describes a novel in-situ method that consists of a thin stainless steel column which can be inserted into constructed biofilters in a non-destructive manner. The in-situ columns (ISCs) were tested using a controlled field-scale biofilter where FCT is possible. Fluorescein was initially used for testing through a series of continuous applications. The results from the ISC were compared to FCT conducted under similar operational conditions. Excellent agreement was obtained for the series of continuous fluorescein experiments, demonstrating that the ISC was able to reproduce FCT results even after extended drying periods (Nash-Sutcliffe coefficient between the two data sets was 0.83-0.88), with similar plateaus, flush peaks, slopes and treatment capacities. The ISCs were then tested for three herbicides: atrazine, simazine and prometryn. While the ISC herbicide data and the FCT data typically matched well, some differences observed were linked to the different climatic conditions during the ISC (winter) and FCT tests (summer). The work showed that ISC is a promising tool to study the field performance of biofilters and could be a potential alternative to full scale challenge tests for validation of stormwater biofilters when taking into account the same inherent boundary conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Urban Stormwater Temperature Surges: A Central US Watershed Study

    Directory of Open Access Journals (Sweden)

    Sean J. Zeiger

    2015-10-01

    Full Text Available Impacts of urban land use can include increased stormwater runoff temperature (Tw leading to receiving water quality impairment. There is therefore a need to target and mitigate sources of thermal pollution in urban areas. However, complex relationships between urban development, stormwater runoff and stream water heating processes are poorly understood. A nested-scale experimental watershed study design was used to investigate stormwater runoff temperature impacts to receiving waters in a representative mixed-use urbanizing watershed of the central US. Daily maximum Tw exceeded 35.0 °C (threshold for potential mortality of warm-water biota at an urban monitoring site for a total of five days during the study period (2011–2013. Sudden increases of more than 1.0 °C within a 15 min time interval of Tw following summer thunderstorms were significantly correlated (CI = 95%; p < 0.01 to cumulative percent urban land use (r2 = 0.98; n = 29. Differences in mean Tw between monitoring sites were significantly correlated (CI = 95%; p = 0.02 to urban land use practices, stream distance and increasing discharge. The effects of the 2012 Midwest USA drought and land use on Tw were also observed with maximum Tw 4.0 °C higher at an urban monitoring site relative to a rural site for 10.5 h. The current work provides quantitative evidence of acute increases in Tw related to urban land use. Results better inform land managers wishing to create management strategies designed to preserve suitable thermal stream habitats in urbanizing watersheds.

  2. Intumescent Coatings as Fire Retardants

    Science.gov (United States)

    Parker, J. A.; Fohlen, G. M.; Sawko, P. M.; Fish, R. H.

    1970-01-01

    The development of fire-retardant coatings to protect surfaces which may be exposed to fire or extreme heat is a subject of intense interest to many industries. A fire-retardant paint has been developed which represents a new chemical approach for preparing intumescent coatings, and potentially, is very important to fire-prevention authorities. The requirements for a superior coating include ease of application, suitability to a wide variety of surfaces and finishes, and stability over an extended period of time within a broad range of ambient temperature and humidity conditions. These innovative coatings, when activated by the heat of a fire, react to form a thick, low-density, polymeric coating or char layer. Water vapor and sulphur dioxide are released during the intumescent reaction. Two fire-protection mechanisms thus become available: (1) the char layer retards the flow of heat, due to the extremely low thermal conductivity; and (2) water vapor and sulfur dioxide are released, providing fire quenching properties. Still another mechanism functions in cases where the char, by virtue of its high oxidation resistance and low thermal conductivity, reaches a sufficiently high temperature to re-radiate much of the incident heat load. The coatings consist of dispersions of selective salts of a nitro-amino-arornatic compound. Specifically, para-nitroaniline bisulfate and the ammonium salt of para-nitroaniline-ortho sulphuric acid (2-amino-5-nitrobenzenesulphuric acid) are used. Suitable vehicles are cellulose nitrate of lacquer grade, a nitrite-phenolic modified rubber, or epoxy-polysulfide copolymer. Three separate formulations have been developed. A solvent is usually employed, such as methylethyl ketone, butyl acetate, or toluene, which renders the coatings suitably thin and which evaporates after the coatings are applied. Generally, the intumescent material is treated as insoluble in the vehicle, and is ground and dispersed in the vehicle and solvent like an

  3. The Mentally Retarded Defendant-Offender.

    Science.gov (United States)

    Reichard, Cary L.; And Others

    1980-01-01

    Three conclusions were drawn regarding the majority of the states: they have not adopted a definition of mental retardation; they have litte information on the prevalence of mentally retarded imprisoned persons; and they are not providing training for judges or lawyers on this topic. (CL)

  4. Defining Mental Retardation from an Instructional Perspective.

    Science.gov (United States)

    Dever, R. B.

    1990-01-01

    A definition of mental retardation is presented to clarify perceptions of what should happen to persons with mental retardation after identification and program placement. The definition refers to the need for specific skill training and the development of independence. A rationale and six corollaries to the definition are discussed. (JDD)

  5. Body Awareness in Children with Mental Retardation

    Science.gov (United States)

    Simons, Johan; Dedroog, Inge

    2009-01-01

    The body awareness of 124 toddlers with mental retardation and of 124 children developing normally matched to them on age and gender was examined. Twenty-nine of the children with mental retardation were diagnosed as Down syndrome (DS). The "Pointing and Naming" Test of Berges and Lezine [Berges, J., & Lezine, I. (1978). "Test d'imitation de…

  6. Flame retardant cotton based highloft nonwovens

    Science.gov (United States)

    Flame retardancy has been a serious bottleneck to develop cotton blended very high specific volume bulky High loft fabrics. Alternately, newer approach to produce flame retardant cotton blended High loft fabrics must be employed that retain soft feel characteristics desirable of furnishings. Hence, ...

  7. CASE REPORT OF A MENTALLY RETARDED CHILD

    Directory of Open Access Journals (Sweden)

    Vasilka GALEVSKA

    2006-06-01

    Full Text Available Mental retardation is a complex individual and social problem. According to WHO, around 1-3 % of world population are mentally retarded people and the percentage between school children is around 2 %.The development of a mentally retarded child depends on factors related to the disability itself, all the limitations and characteristics which results from that. But, physical, psychical, educational and social development of a mentally retarded child, also, depend on other conditions, such as the family and the wider environment, their reactions, attitudes, awareness and sensitivity for special needs of the child, as well as their preparedness and possibilities to respond.At the same time, it is necessary that the mentally retarded child is detected and diagnosed in time, as well as the early start of an adequate treatment.

  8. Identification and Induction of Human, Social, and Cultural Capitals through an Experimental Approach to Stormwater Management

    Directory of Open Access Journals (Sweden)

    Hale W. Thurston

    2012-08-01

    Full Text Available 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 but faces constraints related to land access and citizen engagement. We tested a novel method of environmental management through citizen-based stormwater management on suburban private land. After a nominal induction of human capital through an education campaign, two successive (2007, 2008 reverse auctions engaged residents to voluntarily bid on installation of SWMPs on their property. Cumulatively, 81 rain gardens and 165 rain barrels were installed on approximately one-third of the 350 eligible residential properties in the watershed, resulting in an estimated 360 m3 increase in stormwater detention capacity. One surprising result was the abundance of zero dollar bids, indicating even a limited-effort human capital campaign was sufficient to enroll many participants. In addition, we used statistical methods to illustrate the significant role of social capital in forming clusters of adjacent properties that participated in bidding. This indicated that as participants shared their experiences, neighbors may have become more willing to trust the program and enroll. Significant agglomerations of participating properties may indicate a shift in neighborhood culture regarding stormwater management with positive implications for watershed health through the sustained induction of alternate capitals.

  9. "Triple-bottom-line" assessment of urban stormwater projects.

    Science.gov (United States)

    Taylor, A C; Fletcher, T D

    2006-01-01

    New guidelines have been developed and trialled in Australia to assist urban stormwater managers to assess options for projects that aim to improve urban waterway health. These guidelines help users to examine the financial, ecological and social dimensions of projects (i.e., the so-called "triple-bottom-line"). Features of the assessment process described in the guidelines include use of multi criteria analysis, input from technical experts as well as non-technical stakeholders, and provision of three alternative levels of assessment to suit stormwater managers with differing needs and resources. This paper firstly provides a background to the new guidelines and triple-bottom-line assessment. The assessment methodology promoted in the new guidelines is then briefly summarised. This methodology is compared and contrasted with European guidelines from the "SWARD" project that have been primarily developed for assessing the relative sustainability of options involving urban water supply and sewerage assets. Finally, the paper discusses how assessment methodologies that evaluate the financial, ecological and social dimensions of projects can, under some circumstances, be used to evaluate the relative progress of options for urban water management on a journey towards the widely pursued, but vaguely defined goal of "sustainable development".

  10. Stormwater Management in Urban Areas of South Korea

    Science.gov (United States)

    Memon, S. A.; Raja, O. S.; Kandhro, B.; Salim, I.; Lee, C.-H.

    2018-03-01

    In early start of monitoring, a pathway for high runoff volumes and peak flows during rainfall period towards downstream of a waterbody was provided from storm sewer network, but later on it was realized to deal with stormwater quantity and quality to develop new approaches and management techniques. In early 90’s NPS pollution issue was highlighted in korea, but only limited studies were conceded out up to the year 2000, however reasonably huge numbers of studies were directed for environmental science. After the recognition of NPS, Ministry of Environment in 1998 has introduced NPS as a major contributor in total maximum daily load management system (TPLMS) and waterbodies impairment, which is one of the guidelines of widespread water improvement strategies for main rivers. It contains a number of agendas that intention is to improve, maintain or restore the water quality in national water systems. It can be potted that stormwater management has evolved during the decades as of understanding with its impacts and it has been evolved from focusing on flood control to now incorporating control for volume, erosion and water quality, which is theoretically based on a watershed concept.

  11. Urban stormwater runoff nitrogen composition and fate in bioretention systems.

    Science.gov (United States)

    Li, Liqing; Davis, Allen P

    2014-03-18

    Multiple chemical forms of nitrogen in urban stormwater make its management challenging. Sixteen storm events were monitored and analyzed for total nitrogen (TN), particulate organic nitrogen (PON), nitrate (NO3-N), nitrite (NO2-N), ammonium (NH3-N), and dissolved organic nitrogen (DON) in stormwater runoff and in treated discharge through a conventional bioretention cell. Influent PON can be effectively removed via bioretention sedimentation/filtration, NH3-N by ion exchange/sorption, and NO2-N by oxidation. However, significant DON and NO3-N leached from the bioretention cell, resulting in only 9% net overall TN concentration reduction. Captured PON and vegetation detritus in the bioretention cell can be leached as DON or mineralized into NO3-N. The effluent N is dominated by NO3-N (46%) and DON (42%). Therefore, in addition to creating denitrification conditions for NO3-N, preventing DON leaching is also critical for effective nitrogen removal though bioretention systems. The bioretention cell exhibited a moderate mass load reduction for TN (41%), which mainly results from runoff volume reduction.

  12. Microorganisms in stormwater; a summary of recent investigations

    Science.gov (United States)

    Mallard, Gail E.

    1980-01-01

    All storm runoff contains a variety of bacteria, including total coliform, fecal coliform, and fecal streptococci, which are derived from the land over which the water flows. Most total coliform are native soil organisms, whereas the fecal coliform and fecal streptococci originate from the feces of wild and domestic animals. Urban runoff has been reported to contain pathogenic organisms, but this probably presents little direct threat to human health because the runoff is not ingested. Runoff water can, however, have other negative effects such as contamination of surface water, which may result in beach closures, or contamination of shellfish. This type of contamination is generally of short duration because indicator bacteria and pathogens die out rapidly in the aquatic environment. Similarly, bacteria and viruses deposited on soil by stormwater are inactivated by drying, competition from soil microflora, and a variety of other processes. Every storm producing runoff is unique in the number and type of microorganisms because these vary from site to site, from storm to storm, and during the course of the storm. Stormwater to be examined for microorganisms must be collected in sterile containers and processed immediately. (USGS)

  13. 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.

  14. Modelling of stormwater infiltration for stream restoration. Beder (Aarhus) case study

    DEFF Research Database (Denmark)

    Locatelli, Luca; Bockhorn, Britta; Klint, K. E.

    Stormwater management using Water Sensitive Urban Design (WSUD) is emerging as an alternative to traditional structural engineering solutions. Here stormwater infiltration is analyzed as a means for increasing the flow in a stream with unacceptably low flows during the dry season. The analyses were...... to assess the impact of stormwater runoff infiltration on (1) the water balance; (2) stream flow of the local stream Hovedgrøften; and (3) the risk of polluting the primary aquifer. The hydrogeological model was developed in a deterministic groundwater model (MIKE SHE) which was coupled dynamically...

  15. SLEEP DISORDERS IN MENTALLY RETARDED CHILDREN

    Directory of Open Access Journals (Sweden)

    I. A. Kelmanson

    2014-01-01

    Full Text Available The paper presents the study of the association between sleep disturbances and mental retardation in children. Attention is paid to the instant connection between sleep neurophysiology and intellectual progress, as well as between sleep disorders and the pathogenesis of mental retardation in children. The data on characteristic forms of sleep disturbances, including bed-time resistance, frequent night awakenings, parasomnias, abnormal sleep structure, and notably reduced REM-sleep proportion are provided. The potential role of abnormal melatonin production in the origins of sleep disturbances in children with mental retardation is discussed. Certain approaches to pharmacological and non-pharmacological corrections of sleep disorders are outlined.

  16. How field monitoring of green infrastructure stormwater practices has led to changes in North Carolina's Stormwater BMP design manual

    Science.gov (United States)

    Hunt, W. F.; Winston, R. J.

    2011-12-01

    Green Infrastructure stormwater management is comprised of many biologically-based stormwater treatment practices. Two of which, bioretention and level spreader- vegetative filter strips, have been extensively studied at over 10 different field locations across North Carolina by NC State University. The result of this research has been dramatic changes to the state of North Carolina's stormwater BMP Design Manual, which now allows a greater amount of flexibility for the design of each practice than most other design manuals. The purpose of this presentation is to present a summary of research conducted in North Carolina and associate that research with specific changes made in the state's design guidance for both bioretention (Table 1) and level spreader- vegetated filter strip systems (Table 2). Among the changes are type of vegetation, ratio of hydraulic loading, underdrainage configuration, and fill media selection. References (in print) associated with the tables are listed below: Hathaway, J.M. and W.F. Hunt. 2008. Field Evaluation of Level Spreaders in the Piedmont of North Carolina. Journal of Irrigation and Drainage Engineering, 134(4):538-542. Hunt, W.F., A.R. Jarrett, J.T. Smith, L.J. Sharkey. 2006. Evaluating Bioretention Hydrology and Nutrient Removal at Three Field Sites in North Carolina. Journal of Irrigation and Drainage Engineering, 132 (6): 600-608. Hunt, W.F., J.M. Hathaway, R.J. Winston, and S.J. Jadlocki. 2010. Runoff Volume Reduction by a Level Spreader - Vegetated Filter Strip System in Suburban Charlotte, NC. Journal of Hydrologic Engineering, 15(6): 399-503. Jones, M.P. and W.F. Hunt. 2009. Bioretention Impact on Runoff Temperature in Trout Sensitive Waters. Journal of Environmental Engineering, 135(8): 577-585. Li, H., L.J. Sharkey, W.F. Hunt, A.P. Davis. 2009. Mitigation of Impervious Surface Hydrology using Bioretention in North Carolina and Maryland. Journal of Hydrologic Engineering, 14(4): 407-415. Line, D.E. and W.F. Hunt. 2009

  17. Education of Mentally Retarded Adults

    Directory of Open Access Journals (Sweden)

    Dora Jelenc

    2000-12-01

    Full Text Available Adult education of people with severe, modest and profound mental retardation got only recently an important place in the special education theory and practice. It could be established that in this area both in the intentional as well as in the contentual field the meaningfull shift has been achieved. Today we are talking about authonomy and rights of these people to taking part in a decission-making about the way of their living, but on the other  side the fast development and changes in society are again and again compelling this people to the decisions which they are not able to put into effect and which are burdening them and making them dependent of others. This could partly be prevented by continuing education as it is also true for them that in the stage of initial education they cannot subdue everything what they would need later in their life. Next to the findings of the foreign experts this has been confirmed as well in the first our investigations in this area. Some of the findings will be presented in our paper.

  18. A, a Brominated Flame Retardant

    Directory of Open Access Journals (Sweden)

    Tomomi Takeshita

    2013-01-01

    Full Text Available Tetrabromobisphenol A (TBBPA, a brominated flame retardant, has been found to exacerbate pneumonia in respiratory syncytial virus- (RSV- infected mice. We examined the effect of Brazilian propolis (AF-08 on the exacerbation of RSV infection by TBBPA exposure in mice. Mice were fed a powdered diet mixed with 1% TBBPA alone, 0.02% AF-08 alone, or 1% TBBPA and 0.02% AF-08 for four weeks and then intranasally infected with RSV. TBBPA exposure increased the pulmonary virus titer and level of IFN-γ, a representative marker of pneumonia due to RSV infection, in the lungs of infected mice without toxicity. AF-08 was significantly effective in reducing the virus titers and IFN-γ level increased by TBBPA exposure. Also, AF-08 significantly reduced proinflammatory cytokine (TNF-α and IL-6 levels in the lungs of RSV-infected mice with TBBPA exposure, but Th2 cytokine (IL-4 and IL-10 levels were not evidently increased. Neither TBBPA exposure nor AF-08 treatment affected the anti-RSV antibody production in RSV-infected mice. In flow cytometry analysis, AF-08 seemed to be effective in reducing the ratio of pulmonary CD8a+ cells in RSV-infected mice with TBBPA exposure. TBBPA and AF-08 did not exhibit anti-RSV activity in vitro. Thus, AF-08 probably ameliorated pneumonia exacerbated by TBBPA exposure in RSV-infected mice by limiting excess cellular immune responses.

  19. Considerations for the implementation and operation of stormwater control measure (SCM) performance monitoring systems

    Science.gov (United States)

    Green infrastructure (GI) studies are needed to make informed decisions about whether or not to select GI technologies over traditional urban drainage control methods and to assist in the timing of effective maintenance. Two permeable pavement infiltration stormwater control meas...

  20. Street tree structural differences and associated stormwater benefits in metropolitan Cincinnati, Ohio, USA

    Science.gov (United States)

    Green infrastructure approaches leverage vegetation and soil to improve environmental quality. Municipal street trees are crucial components of urban green infrastructure because they provide stormwater interception benefits and other ecosystem services. Thus, it is important to ...

  1. Evaluation of Biochar to Enhance Green Infrastructure for Removal of Heavy Metals in Stormwater

    Science.gov (United States)

    The changes in the natural North American drainage system over the centuries have given rise to significant modern ecological impacts during high precipitation events. Contaminated stormwater runoff is of particular concern during these events. Urban development increases imperme...

  2. Transport, speciation, toxicity, and treatability of highway stormwater discharged to receiving waters in Louisiana.

    Science.gov (United States)

    2013-01-01

    Stormwater from transportation land uses is a complex heterogeneous mixture of particulate matter, nutrients (phosphorus and nitrogen), heavy metals, inorganic, and organic compounds with variations in flow and mass loadings by orders of magnitude du...

  3. Characterization and environmental management of stormwater runoff from road-salt storage facilities.

    Science.gov (United States)

    2004-01-01

    The objectives of this study were to assess the quantity and quality of salt-contaminated water generated from stormwater runoff at VDOT's salt storage facilities and to evaluate management/treatment alternatives to reduce costs and better protect th...

  4. Stormwater best management practices in an ultra-urban setting : selection and monitoring.

    Science.gov (United States)

    2000-05-01

    This report builds on recent FHWA manuals by expanding and presenting additional data, design criteria, and monitoring study results on : stormwater best management practices (BMPs) implemented in ultra-urban areas. An extensive literature search was...

  5. Effective post-construction best management practices (BMPs) to infiltrate and retain stormwater runoff.

    Science.gov (United States)

    2017-06-01

    Performance analyses of newly constructed linear BMPs in retaining stormwater run-off from 1 in. precipitation in : post-construction highway applications and urban areas were conducted using numerical simulations and field : observation. A series of...

  6. Perspectives on the use of green infrastructure for stormwater management in Cleveland and Milwaukee.

    Science.gov (United States)

    Keeley, Melissa; Koburger, Althea; Dolowitz, David P; Medearis, Dale; Nickel, Darla; Shuster, William

    2013-06-01

    Green infrastructure is a general term referring to the management of landscapes in ways that generate human and ecosystem benefits. Many municipalities have begun to utilize green infrastructure in efforts to meet stormwater management goals. This study examines challenges to integrating gray and green infrastructure for stormwater management, informed by interviews with practitioners in Cleveland, OH and Milwaukee WI. Green infrastructure in these cities is utilized under conditions of extreme fiscal austerity and its use presents opportunities to connect stormwater management with urban revitalization and economic recovery while planning for the effects of negative- or zero-population growth. In this context, specific challenges in capturing the multiple benefits of green infrastructure exist because the projects required to meet federally mandated stormwater management targets and the needs of urban redevelopment frequently differ in scale and location.

  7. Evaluating Use of Sub-Grade Drains with PFC for Stormwater Drainage : final report.

    Science.gov (United States)

    2017-08-01

    The overarching objective of this project is to evaluate the effectiveness of incorporated subgrade drain (usually called underdrain) in the permeable friction course (PFC) pavement to facilitate drainage of stormwater within and on the pavemen...

  8. Engaging Social Capital for Decentralized Urban Stormwater Management (Paper in Non-EPA Proceedings)

    Science.gov (United States)

    Decentralized approaches to urban stormwater management, whereby installations of green infrastructure (e.g., rain gardens, bioswales, constructed wetlands) are dispersed throughout a management area, are cost-effective solutions with co-benefits beyond just water abatement. Inst...

  9. Improving the Hydraulic Performance of Stormwater Infiltration Systems in Clay Tills

    DEFF Research Database (Denmark)

    Bockhorn, Britta

    investigations on two typical Danish clay till sites, and one modeling study with the integrated surface water and groundwater model HydroGeoSphere. The saturated hydraulic conductivity (Ksat) is the most critical soil physical parameter when it comes to sizing stormwater infiltration systems. In the first study......Many cities of the Northern Hemisphere are covered by low permeable clay tills, which pose a challenge for stormwater infiltration practices. However, clay tills are amongst the most heterogeneous types of sediments and hydraulic conductivities can vary by several orders of magnitude. This Ph...... in clay tills has potential for improving the hydraulic performance of stormwater infiltration systems. The third study was an assessment of the influence of small-scale soil physical features in clay tills on the hydraulic performance of stormwater infiltration systems based on a HydroGeoSphere model...

  10. Design methods, selection, and cost-effectiveness of stormwater quality structures

    Science.gov (United States)

    2000-11-01

    Implementation of the National Pollutant Discharge Elimination System (NPDES) and Texas Pollutant : Discharge Elimination System (TPDES) requires that the Texas Department of Transportation (TxDOT) : adopt a variety of stormwater quality measures to ...

  11. GIFMod: A Flexible Modeling Framework For Hydraulic and Water Quality Performance Assessment of Stormwater Green Infrastructure

    Science.gov (United States)

    A flexible framework has been created for modeling multi-dimensional hydrological and water quality processes within stormwater green infrastructures (GIs). The framework models a GI system using a set of blocks (spatial features) and connectors (interfaces) representing differen...

  12. Stormwater Pollution Prevention Plan TA-60 Asphalt Batch Plant Revision 2: January 2017

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, Leonard Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-01

    The Stormwater Pollution Prevention Team (PPT) is applicable to operations at the Technical Area (TA)- 60 Asphalt Batch Plant (ABP) located on Eniwetok Drive/Sigma Mesa, in Los Alamos County, New Mexico at Los Alamos National Laboratory (LANL).

  13. Stormwater Pollution Prevention Plan TA-60 Roads and Grounds Facility and Associated Sigma Mesa Staging Area

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, Leonard Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-01

    This Stormwater Pollution Prevention Plan (SWPPP) is applicable to operations at the Technical Area -60 (TA-60) Roads and Grounds Facility and Associated Sigma Mesa Staging Area off Eniwetok Drive, in Los Alamos County, New Mexico.

  14. Increasing sustainable stormwater management adaption through transdisciplinary research

    Science.gov (United States)

    Wingfield, Thea; Potter, Karen; Jones, Gareth; Spees, Jack; Macdonald, Neil

    2016-04-01

    The Ribble Rivers Trust leads a partnership of land and water management organisations that use a holistic approach to water management in the Ribble catchment. They are interested in incorporating sustainable stormwater systems, into their program of delivery with a view to ensuring that their activities to improve the environments and habitats of the catchment also contribute to reducing flood risk. A methodology, to locate interventions that would slow water within the catchment are identified; however partner buy in, institutional caution and economic barriers are felt to be hindering delivery. In response a transdisciplinary research project in which both the academics of the University of Liverpool and the practitioners of The Ribble Rivers Trust are active investigators has been established. The project aims to increase the uptake of sustainable stormwater management techniques through the analysis of the institutional, experiential and governance processes and their interactions with the physical hydrological processes governing stormwater systems. Research that is transdisciplinary must integrate academic knowledge with practitioner, local understanding and practice. Furthermore methodologies belonging to different academic fields must be blended together to collect, analyse and interpret data in order to examine complex problems through different disciplinary lenses in an integrated way. This approach has been developed in response to the complex relationships of cause and effect of contemporary inter-related economic, environmental and societal challenges. There have been a number of challenges to overcome as transdisciplinary researchers, the first and most important was to understand the different research philosophies and theoretical assumptions behind various natural science and social science research methods. Without this understanding research methodologies could be flawed and would not be effectively integrated and the data would not be

  15. Nanocellular foam with solid flame retardant

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Liang; Kelly-Rowley, Anne M.; Bunker, Shana P.; Costeux, Stephane

    2017-11-21

    Prepare nanofoam by (a) providing an aqueous solution of a flame retardant dissolved in an aqueous solvent, wherein the flame retardant is a solid at 23.degree. C. and 101 kiloPascals pressure when in neat form; (b) providing a fluid polymer composition selected from a solution of polymer dissolved in a water-miscible solvent or a latex of polymer particles in a continuous aqueous phase; (c) mixing the aqueous solution of flame retardant with the fluid polymer composition to form a mixture; (d) removing water and, if present, solvent from the mixture to produce a polymeric composition having less than 74 weight-percent flame retardant based on total polymeric composition weight; (e) compound the polymeric composition with a matrix polymer to form a matrix polymer composition; and (f) foam the matrix polymer composition into nanofoam having a porosity of at least 60 percent.

  16. Intrauterine growth retardation - small events, big consequences

    Directory of Open Access Journals (Sweden)

    Ali Syed R

    2011-09-01

    Full Text Available Abstract Intrauterine growth retardation refers to a rate of growth of a fetus that is less than normal for the growth potential of a fetus (for that particular gestational age. As one of the leading causes of perinatal mortality and morbidity, intrauterine growth retardation has immense implications for the short term and long term growth of children. It is an important public health concern in the developing countries. Health statistics encompassing parameters for maternal and child health in the Indian subcontinent have shown improvement in the past few years but they are still far from perfect. Maternal health, education and empowerment bears a strong influence on perinatal outcomes including intrauterine growth retardation and should be the primary focus of any stratagem targeted at reducing the incidence of intrauterine growth retardation. A concerted liaison of various medical and social disciplines is imperative in this regard.

  17. Retarded distances and the Doppler effect

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1992-01-01

    A relativistic transformation of the retarded distance is presented. Arguments of general nature in favour of the concept of the relativistic (radar) length leading to this formula are presented. 10 refs

  18. Agent-based assessment of stormwater re-use potential of low-impact development control facilities at the site of Vlasina Lake, Serbia.

    Science.gov (United States)

    Blagojević, Borislava; Milićević, Dragan; Potić, Olivera

    2013-01-01

    Vlasina Lake in south-east Serbia is classified as an Area of Distinct Land Use and, as such, is subject to high environmental protection standards applied in the Master Plan. Two open channels for stormwater and sediment transportation to two large detention basins with pumping stations for water evacuation into the lake were envisaged in the Master Plan. In the preliminary design, the stormwater system was quite different: wherever possible, on-site natural features were used for allocation of ponds, and drainage channels were led through existing road culverts. The applied design concept has been low impact development (LID), which led to potential blue-green corridors, recognized by project stakeholders. The paper studies the possibility of using ponds as a key element of both the LID concept and the blue-green corridors approach. For that purpose, an initial Vlasina Lake site agent-based simulation model has been created. A realistic physical model is included, and simulation results for two hypothetical climatic and socio-economic scenarios are presented. From the experience in creating the agent-based model, and based on the simulation results, recommendations are given for further work. It is shown that ponds have potential for the investigated water re-use purposes.

  19. DayWater: an Adaptive Decision Support System for Urban Stormwater Management

    OpenAIRE

    Thevenot, Daniel,

    2008-01-01

    International audience; The European DayWater project has developed a prototype of an Adaptive Decision Support System (ADSS) related to urban stormwater pollution source control. The DayWater ADSS greatly facilitates decision-making for stormwater source control, which is currently impeded by the large number of stakeholders involved and by the necessary multidisciplinary knowledge. This book presents the results of this project, providing new insights into both technical and management issu...

  20. 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...

  1. Influence of stormwater runoff on macroinvertebrates in a small urban river and a reservoir.

    Science.gov (United States)

    Gołdyn, Ryszard; Szpakowska, Barbara; Świerk, Dariusz; Domek, Piotr; Buxakowski, Jan; Dondajewska, Renata; Barałkiewicz, Danuta; Sajnóg, Adam

    2018-06-01

    The impact of stormwater on benthic macroinvertebrates was studied in two annual cycles. Five small catchments drained by stormwater sewers to a small urban river and a small and shallow reservoir situated in its course were selected. These catchments were located in residential areas with single-family houses or blocks of flats as well as industrial areas, i.e., a car factory, a glassworks and showroom as well as the parking lots of a car dealer and servicing company. In addition to the five stations situated in the vicinity of the stormwater outlets, three stations not directly influenced by stormwater were also established. Macroinvertebrates were sampled in every season, four times per year. Both abundance and biomass were assessed. Stormwater from industrial areas associated with cars, whose catchments showed a high percentage of impervious areas, had the greatest impact on benthic macroinvertebrates. This was due to a large amount of stormwater and its contamination, including heavy metals. Stormwater outflow from residential multi-family houses exerted the least influence. Macroinvertebrates in the water reservoir were found to undergo more extensive changes than those in the river. The cascade of four reservoirs resulted in a marked improvement of water quality in the river, which was confirmed by species composition, abundance and biomass of macroinvertebrates and indicators calculated on their basis for the stations below the cascade in comparison to the stations above and in the first reservoir. These reservoirs replaced constructed wetlands or other measures, which should be undertaken for stormwater management prior to its discharge into urban rivers and other water bodies. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. The Revised AAMR Definition of Mental Retardation: The MRDD Position.

    Science.gov (United States)

    Smith, J. David

    1994-01-01

    The Division on Mental Retardation and Developmental Disabilities (MRDD) of the Council for Exceptional Children adopted this position statement concerning the revised American Association on Mental Retardation (AAMR) definition of mental retardation. The position statement views the revised mental retardation definition and classification as a…

  3. Analysis of radiation polymerization of flame retarder

    International Nuclear Information System (INIS)

    Enomoto, Ichiro; Sawai, Takeshi; Ametani, Kazuo

    1990-01-01

    It was found that when vinyl phosphonate oligomer was irradiated with electron beam, the decrease of thermogravity in three steps arose. It was presumed that the first decrease of weight was due to the vaporization of water. This value is nearly constant independent of dose, but when divided irradiation was carried out, as dose increased, the decrease of weight became less. Fire damages have increased as population concentrates into cities and overcrowding occurs. To make combustible materials as well as the textile products belonging to people flame-retardant has become a social problem. The flame retarders and the method of processing which do not generate harmful gas in combustion are demanded. The practical test on making fibers flame-retardant by using radiation graft polymerization has been carried out since 1984, and the method of processing without generating harmful gas was obtained. It is necessary to elucidate the basic property of flame retarders due to irradiation for further developing the technology of flame retardation. This time, the thermogravimetric change of the flame retarders polymerized with radiation was examined. The experimental method and the results are reported. (K.I.)

  4. Mental Retardation, Poverty and Community Based Rehabilitation

    Directory of Open Access Journals (Sweden)

    Einar Helander

    2009-10-01

    Full Text Available A person with moderate mental retardation would, in a western country, be "diagnosed" early on in life. Consequently, such a child is likely to be sent for special education. Given the high level of job requirements, such a person is unlikely to be employed in the open market later in life. Mental retardation is one of the most frequent disabilities in most studies, mental retardation is found in about three percent of the population. Persons even with mild mental retardation have very large difficulties finding employment and are for this reason often deprived of opportunities for suitable and productive income generation this is why most stay poor. But disability does not only cause poverty poverty itself causes disability. This study follows an analysis, based on a review of the Swedish programme for mental retardation during the period 1930-2000. It is concluded that in Sweden a very large proportion of mild and moderate mental retardation has been eliminated though the combination of poverty alleviation with a community-based rehabilitation programme. For these situations a pro-active programme analysing and meeting the needs of the target groups should be useful as a means to achieve poverty alleviation.

  5. Characterization of Stormwater Runoff from a Light Rail Transit Area.

    Science.gov (United States)

    Sajjad, Raja Umer; Kim, Kyoung Jin; Memon, Sheeraz; Sukhbaatar, Chinzorig; Paule, Ma Cristina; Lee, Bum-Yeon; Lee, Chang-Hee

    2015-09-01

    The monitoring of stormwater runoff from Light Rail Transit (LRT) facilities is insufficient in many regions around the world. In this study, runoff quality and quantity were monitored during operational and non-operational LRT phases during 2010-2013. The event mean concentration (EMC) of pollutants showed little statistical variability during both phases. The antecedent dry day (ADD) showed a strong to moderate positive correlation with most pollutant EMCs during the non-operational phase. The existence and magnitude of the first flush from LRT runoff was found to be similar to those from other transportation land uses. The comparison of LRT runoff data with an adjacent road bridge site showed that the pollutant EMC and unit load were 2 to 9 times higher from the road bridge. It was suggested that LRT automated operation and the elevated track makes this transportation mode a viable option for the management of non-point source pollution.

  6. Balancing the Ecological Function of Residential Stormwater Ponds with Homeowner Landscaping Practices.

    Science.gov (United States)

    Monaghan, Paul; Hu, Shangchun; Hansen, Gail; Ott, Emily; Nealis, Charles; Morera, Maria

    2016-11-01

    Stormwater ponds are installed in urban developments to provide the ecosystem services of flood control and water treatment. In coastal areas, these ponds are connected to watersheds that can drain directly into protected estuaries, making their design, function, and maintenance critical to environmental protection. However, stormwater ponds in residential areas are increasingly managed as aesthetic amenities that add value to real estate rather than as engineered devices with special maintenance requirements. To help extend the life of neighborhood stormwater systems and improve ecosystem services, homeowners should follow best management practices for nutrient management and add shoreline plantings and non-invasive, beneficial aquatic plants to their ponds. This study used focus group and survey research to document the knowledge, behaviors, and attitudes of homeowners living near stormwater ponds in a master-planned community in Florida. The study was designed to use a social marketing research approach to promote Extension best practices. Findings indicate that many residents were aware of the functional components of stormwater systems and respondents' receptivity to best management practices was mediated by age, their attitudes about water quality and whether their home was adjacent to a pond. These findings can be used to target Extension audiences and improve adoption of stormwater pond best management practices for increased protection of water quality.

  7. Balancing the Ecological Function of Residential Stormwater Ponds with Homeowner Landscaping Practices

    Science.gov (United States)

    Monaghan, Paul; Hu, Shangchun; Hansen, Gail; Ott, Emily; Nealis, Charles; Morera, Maria

    2016-11-01

    Stormwater ponds are installed in urban developments to provide the ecosystem services of flood control and water treatment. In coastal areas, these ponds are connected to watersheds that can drain directly into protected estuaries, making their design, function, and maintenance critical to environmental protection. However, stormwater ponds in residential areas are increasingly managed as aesthetic amenities that add value to real estate rather than as engineered devices with special maintenance requirements. To help extend the life of neighborhood stormwater systems and improve ecosystem services, homeowners should follow best management practices for nutrient management and add shoreline plantings and non-invasive, beneficial aquatic plants to their ponds. This study used focus group and survey research to document the knowledge, behaviors, and attitudes of homeowners living near stormwater ponds in a master-planned community in Florida. The study was designed to use a social marketing research approach to promote Extension best practices. Findings indicate that many residents were aware of the functional components of stormwater systems and respondents' receptivity to best management practices was mediated by age, their attitudes about water quality and whether their home was adjacent to a pond. These findings can be used to target Extension audiences and improve adoption of stormwater pond best management practices for increased protection of water quality.

  8. Characterizing the Effects of Stormwater Mitigation on Nutrient Export and Stream Concentrations

    Science.gov (United States)

    Bell, Colin D.; McMillan, Sara K.; Clinton, Sandra M.; Jefferson, Anne J.

    2017-04-01

    Urbanization increases nutrient loading and lowers residence times for processing of reactive solutes, including nitrate, total dissolved nitrogen, orthophosphate, and dissolved organic carbon), which leads to increased stream concentrations and mass export. Stormwater control measures mitigate the impacts of urbanization, and have the potential to improve stream water quality, however the net effect instream is not well understood. We monitored two urban and two suburban watersheds in Charlotte, NC to determine if mitigation controlled the fraction of total mass export during storm, if development classification as either urban or suburban (defined by the age, density and distribution of urban development) controlled storm nutrient and carbon dynamics, and if stormwater control measures were able to change stream water chemistry. While average concentrations during stormflow were generally greater than baseflow, indicating that storms are important times of solute export, the fraction of storm-derived export was unrelated to mitigation by stormwater control measures. Development classification was generally not an important control on export of N and dissolved organic carbon. However, event mean concentrations of orthophosphate were higher at the suburban sites, possibly from greater fertilizer application. Stormwater control measures influenced instream water chemistry at only one site, which also had the greatest mitigated area, but differences between stormwater control measure outflow and stream water suggest the potential for water quality improvements. Together, results suggest stormwater control measures have the potential to decrease solute concentrations from urban runoff, but the type, location, and extent of urban development in the watershed may influence the magnitude of this effect.

  9. Impediments to integrated urban stormwater management: the need for institutional reform.

    Science.gov (United States)

    Brown, Rebekah R

    2005-09-01

    It is now well established that the traditional practice of urban stormwater management contributes to the degradation of receiving waterways, and this practice was more recently critiqued for facilitating the wastage of a valuable water resource. However, despite significant advances in alternative "integrated urban stormwater management" techniques and processes over the last 20 years, wide-scale implementation has been limited. This problem is indicative of broader institutional impediments that are beyond current concerns of strengthening technological and planning process expertise. Presented here is an analysis of the institutionalization of urban stormwater management across Sydney with the objective of scoping institutional impediments to more sustainable management approaches. The analysis reveals that the inertia with the public administration of urban stormwater inherently privileges and perpetuates traditional stormwater management practices at implementation. This inertia is characterized by historically entrained forms of technocratic institutional power and expertise, values and leadership, and structure and jurisdiction posing significant impediments to change and the realization of integrated urban stormwater management. These insights strongly point to the need for institutional change specifically directed at fostering horizontal integration of the various functions of the existing administrative regime. This would need to be underpinned with capacity-building interventions targeted at enabling a learning culture that values integration and participatory decision making. These insights also provide guideposts for assessing the institutional and capacity development needs for improving urban water management practices in other contexts.

  10. Characterizing the Effects of Stormwater Mitigation on Nutrient Export and Stream Concentrations.

    Science.gov (United States)

    Bell, Colin D; McMillan, Sara K; Clinton, Sandra M; Jefferson, Anne J

    2017-04-01

    Urbanization increases nutrient loading and lowers residence times for processing of reactive solutes, including nitrate, total dissolved nitrogen, orthophosphate, and dissolved organic carbon), which leads to increased stream concentrations and mass export. Stormwater control measures mitigate the impacts of urbanization, and have the potential to improve stream water quality, however the net effect instream is not well understood. We monitored two urban and two suburban watersheds in Charlotte, NC to determine if mitigation controlled the fraction of total mass export during storm, if development classification as either urban or suburban (defined by the age, density and distribution of urban development) controlled storm nutrient and carbon dynamics, and if stormwater control measures were able to change stream water chemistry. While average concentrations during stormflow were generally greater than baseflow, indicating that storms are important times of solute export, the fraction of storm-derived export was unrelated to mitigation by stormwater control measures. Development classification was generally not an important control on export of N and dissolved organic carbon. However, event mean concentrations of orthophosphate were higher at the suburban sites, possibly from greater fertilizer application. Stormwater control measures influenced instream water chemistry at only one site, which also had the greatest mitigated area, but differences between stormwater control measure outflow and stream water suggest the potential for water quality improvements. Together, results suggest stormwater control measures have the potential to decrease solute concentrations from urban runoff, but the type, location, and extent of urban development in the watershed may influence the magnitude of this effect.

  11. 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.

  12. 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

  13. Enhanced Stormwater Contaminant Removal Using Tree Filters And Modified Sorbents

    Science.gov (United States)

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

    2012-12-01

    Stormwater runoff, particularly in urban areas, contains several groups of contaminants that negatively impact surface- and groundwater quality if left untreated. Contaminants in runoff are often addressed by structural best management practices (BMP) that capture and treat runoff before discharging it. Many BMPs, 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, three materials (red cedar wood chips, expanded shale, and crushed concrete) 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 of the three materials investigated, wood chips exhibit the highest sorption capacity for QAS, making this material favorable for treating bacteria, while at the same time attenuating PAHs by sorption processes. In case of AgNP amendments to wood, less uptake and more desorption from the wood matrix was observed. Relative to wood, expanded shale and crushed concrete exhibited less affinity for QAS (results for AgNPs are pending). Currently, batch isotherm and unsaturated flow column studies are under way to determine the performance of the amended materials with regard to removal of bacteria, nutrients, heavy metals, and PAH from artificially contaminated runoff. In this presentation, the contaminant removal efficiency of all 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.

  14. Stormwater loadings of antibiotic resistance genes in an urban stream.

    Science.gov (United States)

    Garner, Emily; Benitez, Romina; von Wagoner, Emily; Sawyer, Richard; Schaberg, Erin; Hession, W Cully; Krometis, Leigh-Anne H; Badgley, Brian D; Pruden, Amy

    2017-10-15

    Antibiotic resistance presents a critical public health challenge and the transmission of antibiotic resistance via environmental pathways continues to gain attention. Factors driving the spread of antibiotic resistance genes (ARGs) in surface water and sources of ARGs in urban stormwater have not been well-characterized. In this study, five ARGs (sul1, sul2, tet(O), tet(W), and erm(F)) were quantified throughout the duration of three storm runoff events in an urban inland stream. Storm loads of all five ARGs were significantly greater than during equivalent background periods. Neither fecal indicator bacteria measured (E. coli or enterococci) was significantly correlated with sul1, sul2, or erm(F), regardless of whether ARG concentration was absolute or normalized to 16S rRNA levels. Both E. coli and enterococci were correlated with the tetracycline resistance genes, tet(O) and tet(W). Next-generation shotgun metagenomic sequencing was conducted to more thoroughly characterize the resistome (i.e., full complement of ARGs) and profile the occurrence of all ARGs described in current databases in storm runoff in order to inform future watershed monitoring and management. Between 37 and 121 different ARGs were detected in each stream sample, though the ARG profiles differed among storms. This study establishes that storm-driven transport of ARGs comprises a considerable fraction of overall downstream loadings and broadly characterizes the urban stormwater resistome to identify potential marker ARGs indicative of impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. (Dahomey) Basin

    African Journals Online (AJOL)

    Timothy Ademakinwa

    13 km maximum width in the onshore at the basin axis along Nigerian and Republic of Benin boundary. This narrows westwards and eastwards to about 5 km (Coker and Ejedawe, 1987; Coker,. 2002). Detailed geology, evolution, stratigraphy and hydrocarbon occurrence of the basin have been described by Jones and ...

  17. Adapting the social-ecological system framework for urban stormwater management: the case of green infrastructure adoption

    OpenAIRE

    Carli D. Flynn; Cliff I. Davidson

    2016-01-01

    Stormwater management has long been a critical societal and environmental challenge for communities. An increasing number of municipalities are turning to novel approaches such as green infrastructure to develop more sustainable stormwater management systems. However, there is a need to better understand the technological decision-making processes that lead to specific outcomes within urban stormwater governance systems. We used the social-ecological system (SES) framework to build a classifi...

  18. Linking collection of stormwater runoff to managed aquifer recharge using a geographic information system and hydrologic modeling

    Science.gov (United States)

    Teo, E. K.; Young, K. S.; Beganskas, S.; Fisher, A. T.; Lozano, S.; Weir, W. B.; Harmon, R. E.

    2016-12-01

    We are completing a regional analysis of Santa Cruz and northern Monterey Counties, CA to assess conditions for using distributed stormwater collection to support managed aquifer recharge (DSC-MAR). DSC-MAR constitutes an important component in a portfolio of innovative techniques being developed in order to improve groundwater management and to adapt to prolonged drought and changes in climate and anthropogenic water demands by increasing recharge during and soon after winter precipitation events, the season when excess water is most abundant. Our analyses focus specifically on the distributed collection of stormwater runoff, a source that has historically been treated as a nuisance, with the goal of infiltrating ≥100 ac-ft/yr within individual projects. The first part of this project is a spatial analysis, using a geographic information system to combine surface and subsurface data. There is complete spatial coverage for most surface data (elevation, soil and bedrock properties, land use) for the full study region ( 1,400 km2), but subsurface data (aquifer distribution, properties, and storage space) are available for only 43% of the region. Sites that are most suitable for DSC-MAR have high soil infiltration capacity, are well-connected to an underlying aquifer with good transmissive and storage properties, and have space to receive water. Based on surface data, 35% of the region is suitable for MAR (480 km2). In contrast, 14% of the area for which both surface and subsurface datasets are available is suitable for MAR (84 km2). We have assessed the availability of hillslope runoff for collection in support of MAR using a distributed hydrologic model (PRMS) and a catalog of historical, high-resolution climate data. In the simulations, enclosed topographic basins are divided into hydrologic response units (HRUs) having an area of 25 to 250 acres (0.1 to 1 km2). Simulations of the San Lorenzo River Basin (SLRB), northern Santa Cruz County, suggest that during

  19. The necessity of the integral way of stormwater planning and management with a focus to the city of Pirot

    Directory of Open Access Journals (Sweden)

    Milićević Dragan B.

    2015-01-01

    Full Text Available The paper presents problems of stormwater drainage on urban areas, with a focus on the city of Pirot. In the city of Pirot drainage problems have previously been addressed inadequately, the traditional way, based on collecting all stormwater from the city area by combined sewer system and its drainage to the neares recipient, not taking into account the city growth and urbanisation. The paper shows the importance of integral way of stormwater planning and management in the urban areas and gives a summary of the methods and procedures for control of stormwater runoff on urban areas.

  20. Using Value-Focused Thinking to Evaluate the Use of Innovative Stormwater Management Technologies on Air Force Installations

    National Research Council Canada - National Science Library

    Falcone, Jeffrey T

    2007-01-01

    .... It also prevents contaminants from being naturally filtered out of stormwater flows. As a result, centralized conveyance systems can cause flooding, erosion, and terrestrial/aquatic habitat degradation...

  1. Intrauterine radiation exposures and mental retardation

    International Nuclear Information System (INIS)

    Miller, R.W.

    1988-01-01

    Small head size and mental retardation have been known as effects of intrauterine exposure to ionizing radiation since the 1920s. In the 1950s, studies of Japanese atomic-bomb survivors revealed that at 4-17 wk of gestation, the greater the dose, the smaller the brain (and head size), and that beginning at 0.5 Gy (50 rad) in Hiroshima, mental retardation increased in frequency with increasing dose. No other excess of birth defects was observed. Otake and Schull (1984) pointed out that the period of susceptibility to mental retardation coincided with that for proliferation and migration of neuronal elements from near the cerebral ventricles to the cortex. Mental retardation could be the result of interference with this process. Their analysis indicated that exposures at 8-15 wk to 0.01-0.02 Gy (1-2 rad) doubled the frequency of severe mental retardation. This estimate was based on small numbers of mentally retarded atomic-bomb survivors. Although nuclear accidents have occurred recently, new cases will hopefully be too rare to provide further information about the risk of mental retardation. It may be possible, however, to learn about lesser impairment. New psychometric tests may be helpful in detecting subtle deficits in intelligence or neurodevelopmental function. One such test is PEERAMID, which is being used in schools to identify learning disabilities due, for example, to deficits in attention, short- or long-term memory, or in sequencing information. This and other tests could be applied in evaluating survivors of intrauterine exposure to various doses of ionizing radiation. The results could change our understanding of the safety of low-dose exposures

  2. Intrauterine radiation exposures and mental retardation

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.W.

    1988-08-01

    Small head size and mental retardation have been known as effects of intrauterine exposure to ionizing radiation since the 1920s. In the 1950s, studies of Japanese atomic-bomb survivors revealed that at 4-17 wk of gestation, the greater the dose, the smaller the brain (and head size), and that beginning at 0.5 Gy (50 rad) in Hiroshima, mental retardation increased in frequency with increasing dose. No other excess of birth defects was observed. Otake and Schull (1984) pointed out that the period of susceptibility to mental retardation coincided with that for proliferation and migration of neuronal elements from near the cerebral ventricles to the cortex. Mental retardation could be the result of interference with this process. Their analysis indicated that exposures at 8-15 wk to 0.01-0.02 Gy (1-2 rad) doubled the frequency of severe mental retardation. This estimate was based on small numbers of mentally retarded atomic-bomb survivors. Although nuclear accidents have occurred recently, new cases will hopefully be too rare to provide further information about the risk of mental retardation. It may be possible, however, to learn about lesser impairment. New psychometric tests may be helpful in detecting subtle deficits in intelligence or neurodevelopmental function. One such test is PEERAMID, which is being used in schools to identify learning disabilities due, for example, to deficits in attention, short- or long-term memory, or in sequencing information. This and other tests could be applied in evaluating survivors of intrauterine exposure to various doses of ionizing radiation. The results could change our understanding of the safety of low-dose exposures.

  3. Applying a regional hydrology model to evaluate locations for groundwater replenishment with hillslope runoff under different climate and land use scenarios in an agricultural basin, central coastal California

    Science.gov (United States)

    Beganskas, S.; Young, K. S.; Fisher, A. T.; Lozano, S.; Harmon, R. E.; Teo, E. K.

    2017-12-01

    We are applying a regional hydrology model, Precipitation-Runoff Modeling System (PRMS), to evaluate locations for groundwater replenishment with hillslope runoff in the Pajaro Valley Groundwater Basin (PVGB), central coastal California. Stormwater managed aquifer recharge (MAR) projects collect hillslope runoff before it reaches a stream and infiltrate it into underlying aquifers, improving groundwater supply. The PVGB is a developed agricultural basin where groundwater provides >85% of water for irrigation and municipal needs; stormwater-MAR projects are being considered to address chronic overdraft and saltwater intrusion. We are applying PRMS to assess on a subwatershed scale (10-100 ha; 25-250 acres) where adequate runoff is generated to supply stormwater-MAR in coincidence with suitable conditions for infiltration and recharge. Data from active stormwater-MAR projects in the PVGB provide ground truth for model results. We are also examining how basinwide hydrology responds to changing land use and climate, and the potential implications for future water management. To prepare extensive input files for PRMS models, we developed ArcGIS and Python tools to delineate a topographic model grid and incorporate high-resolution soil, vegetation, and other physical data into each grid region; we also developed tools to analyze and visualize model output. Using historic climate records, we generated dry, normal, and wet climate scenarios, defined as having approximately 25th, 50th, and 75th percentile annual rainfall, respectively. We also generated multiple land use scenarios by replacing developed areas with native vegetation. Preliminary results indicate that many parts of the PVGB generate significant runoff and have suitable infiltration/recharge conditions. Reducing basinwide overdraft by 10% would require collecting less than 5% of total hillslope runoff, even during the dry scenario; this demonstrates that stormwater-MAR could be an effective water management

  4. Effect of Disc Filtration with and without Addition of Flocculent on Nano- and Micro-Particles and Their Associated Polycyclic Aromatic Hydrocarbons in Stormwater

    DEFF Research Database (Denmark)

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

    2015-01-01

    Many municipalities in Denmark and around Europe currently work towards separating stormwater and sewage. In existing urban areas this may imply disconnecting stormwater from the old combined sewer systems suffering from hydraulic overloading and discharging directly to nearby surface waters...

  5. Assessment of Pollutant Removal Efficiency and Drainage Capacity in Stormwater Biofilters

    Science.gov (United States)

    Carroll, S. J.; Mills, H.; Reagan, A.; Triassi, M.; Bauer, S.; Matiasek, S. J.; Libby, R.; Meddings, C.

    2016-12-01

    Urban stormwater runoff contributes to flooding and impacts water quality with increased sediment and pollutant loads. Biofilters are vegetated filtration systems designed to mitigate stormwater by enhancing infiltration, sedimentation, contaminant sorption and uptake. Despite the rapid implementation of biofilters as stormwater management solutions, their performance is mainly evaluated in terms of flood reduction while their pollutant removal efficiency is rarely assessed. We investigated the effect of biofilter composition on drainage capacity and individual pollutant removal in test columns. Triplicate columns consisted of layers of pebbles, fine sand, filtration mix (test variable), mulch, lava rock and Santa Barbara sedges. The filtration mix was one of five combinations of coarse sand and local loam soil ranging from 100% sand to 100% soil. Consistent with differences in pore size distribution, hydraulic conductivity values were lowest in 100% soil biofilters (3.0 ± 0.6 mm/h) and highest in the 100% sand biofilters (22.7 ± 4.2 mm/h). A synthetic mixture of nutrients, metals, and salts in proportions representative of stormwater composition was applied to the test columns. Biofilters removed over 98% of dissolved copper, nickel, and zinc, and at least 67% of dissolved lead, even when applying synthetic runoff with metal concentrations three orders of magnitude larger than in actual stormwater. In addition, biofilters oxygenated, neutralized, and decreased the turbidity of stormwater. Ammonium was quantitatively removed from synthetic runoff (97-100%), while nitrate and phosphate were poorly retained (48-64%) or even leached from sand biofilters. This study demonstrated that, while decreasing drainage capacity, adding even a small proportion of native soil to the filtration media significantly increases pollutant removal of biofilters. With proper consideration of the filtration mixture, biofiltration systems can effectively remediate urban stormwater.

  6. Integral stormwater management master plan and design in an ecological community.

    Science.gov (United States)

    Che, Wu; Zhao, Yang; Yang, Zheng; Li, Junqi; Shi, Man

    2014-09-01

    Urban stormwater runoff nearly discharges directly into bodies of water through gray infrastructure in China, such as sewers, impermeable ditches, and pump stations. As urban flooding, water shortage, and other environment problems become serious, integrated water environment management is becoming increasingly complex and challenging. At more than 200ha, the Oriental Sun City community is a large retirement community located in the eastern side of Beijing. During the beginning of its construction, the project faced a series of serious water environment crises such as eutrophication, flood risk, water shortage, and high maintenance costs. To address these issues, an integral stormwater management master plan was developed based on the concept of low impact development (LID). A large number of LID and green stormwater infrastructure (GSI) approaches were designed and applied in the community to replace traditional stormwater drainage systems completely. These approaches mainly included bioretention (which captured nearly 85th percentile volume of the annual runoff in the site, nearly 5.4×10(5)m(3) annually), swales (which functioned as a substitute for traditional stormwater pipes), waterscapes, and stormwater wetlands. Finally, a stormwater system plan was proposed by integrating with the gray water system, landscape planning, an architectural master plan, and related consultations that supported the entire construction period. After more than 10 years of planning, designing, construction, and operation, Oriental Sun City has become one of the earliest modern large-scale LID communities in China. Moreover, the project not only addressed the crisis efficiently and effectively, but also yielded economic and ecological benefits. Copyright © 2014. Published by Elsevier B.V.

  7. Urban Stormwater Quality: Linking Pesticide Variability To Our Sustainable Water Future

    Science.gov (United States)

    Rippy, M.; Deletic, A.; Gernjak, W.

    2015-12-01

    Climate change and global population growth demand creative, multidisciplinary, and multi-benefit approaches for sustaining adequate fresh water resources and protecting ecosystem health. Currently, a driving factor of aquatic ecosystem degradation (stormwater) is also one of the largest untapped urban freshwater resources. This suggests that ecosystem protection and potable water security might both be achieved via treating and capturing stormwater for human use (e.g., potable substitution). The viability of such a scheme, however, depends on 1) initial stormwater quality (e.g., the contaminants present and their associated human/environmental health risks), 2) the spatial and temporal variability of contaminants in stormwater, and 3) the capacity of existing technologies to treat those contaminants to fit for purpose standards. Here we present results from a four year study of urban stormwater conducted across ten catchments and four states in Australia that addresses these three issues relative to stormwater pesticides. In total, 19 pesticides were detected across all sites and times. In general, pesticide concentrations were lower than has been reported in other countries, including the United States, Canada and Europe. This is reflected in few exceedences of public health (< 1%) and aquatic ecosystem standards (0% for invertebrates and fish, < 1% for algae and plants). Interestingly, pesticide patterns were found to be stable across seasons, and years, but varied across catchments. These catchment-specific fingerprints may reflect preferential commercial product use, as they map closely to co-occurrence patterns in registered Australian products. Importantly, the presence of catchment-specific pesticide variability has clear management implications; namely, urban stormwater must be managed at the catchment level and target local contaminant suites in order to best achieve desired human use and environmental protection standards.

  8. Flame-retardant carbon nanotube films

    Science.gov (United States)

    Janas, Dawid; Rdest, Monika; Koziol, Krzysztof K. K.

    2017-07-01

    We have demonstrated fire-retardancy properties of a polymer matrix-free CNT film for the first time. As compared with classical fire-retardant materials such as Kevlar, Twaron or Nomex, the CNT film showed a spectrum of advantages. The material is lightweight, flexible and well-adherent to even the most complicated shapes. The results have showed that by using CNTs for fire-retardancy we can extend the operational time almost two-fold, what makes CNTs a much better protection than the solutions employed nowadays. We believe that among other great properties of CNT, their macroscopic assemblies such as CNT films show significant potential for becoming a fire protective coating, which exhibits high performance in not sustaining fire.

  9. 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

  10. Water management during climate change using aquifer storage and recovery of stormwater in a dunefield in western Saudi Arabia

    KAUST Repository

    Lopez Valencia, Oliver Miguel

    2014-07-28

    An average of less than 50 mm yr-1 of rainfall occurs in the hyperarid region of central Western Saudi Arabia. Climate change is projected to create greater variation in rainfall accumulation with more intense rainfall and flood events and longer duration droughts. To manage climate change and variability in ephemeral stream basins, dams are being constructed across wadi channels to capture stormwater, but a large percentage of this stored water is lost to evaporation. A dam/reservoir system located in Wadi Al Murwani in Western Saudi Arabia was recently constructed and is expected to contain a maximum stored water volume of 150 million m3. A hydrologic assessment of a dunefield lying 45 km downstream was conducted to evaluate its potential use for aquifer storage and recovery of the reservoir water. A 110 m elevation difference between the base of the dam and the upper level of the dunefield occurs, allowing conveyance of the water from the reservoir to the dunefield storage site by gravity feed without pumping, making the recharge system extremely energy efficient. Aquifer storage and recovery coupled with dams would allow water management during extreme droughts and climate change and has widespread potential application in arid regions. 2014 IOP Publishing Ltd.

  11. Assessment of public health risk associated with viral contamination in harvested urban stormwater for domestic applications

    International Nuclear Information System (INIS)

    Lim, Keah-Ying; Hamilton, Andrew J.; Jiang, Sunny C.

    2015-01-01

    Capturing stormwater is becoming a new standard for sustainable urban stormwater management, which can be used to supplement water supply portfolios in water-stressed cities. The key advantage of harvesting stormwater is to use low impact development (LID) systems for treatment to meet water quality requirement for non-potable uses. However, the lack of scientific studies to validate the safety of such practice has limited its adoption. Microbial hazards in stormwater, especially human viruses, represent the primary public health threat. Using adenovirus and norovirus as target pathogens, we investigated the viral health risk associated with a generic scenario of urban stormwater harvesting practice and its application for three non-potable uses: 1) toilet flushing, 2) showering, and 3) food-crop irrigation. The Quantitative Microbial Risk Assessment (QMRA) results showed that food-crop irrigation has the highest annual viral infection risk (median range: 6.8 × 10 −4 –9.7 × 10 −1 per-person-per-year or pppy), followed by showering (3.6 × 10 −7 –4.3 × 10 −2 pppy), and toilet flushing (1.1 × 10 −7 –1.3 × 10 −4 pppy). Disease burden of each stormwater use was ranked in the same order as its viral infection risk: food-crop irrigation > showering > toilet flushing. The median and 95th percentile risk values of toilet-flushing using treated stormwater are below U.S. EPA annual risk benchmark of ≤ 10 −4 pppy, whereas the disease burdens of both toilet-flushing and showering are within the WHO recommended disease burdens of ≤ 10 −6 DALYs pppy. However, the acceptability of showering risk interpreted based on the U.S. EPA and WHO benchmarks is in disagreement. These results confirm the safety of stormwater application in toilet flushing, but call for further research to fill the data gaps in risk modeling as well as risk benchmarks. - Highlights: • Human health risks for three non-potable uses of treated stormwater are modeled. • Crop

  12. Assessment of public health risk associated with viral contamination in harvested urban stormwater for domestic applications

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Keah-Ying [Department of Civil and Environmental Engineering, University of California, Irvine, CA 92617-2175 (United States); Hamilton, Andrew J. [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Dookie Campus, Currawa, VIC 3647 (Australia); Federation University Australia, Mt Helen Campus, VIC 3353 (Australia); Jiang, Sunny C., E-mail: sjiang@uci.edu [Department of Civil and Environmental Engineering, University of California, Irvine, CA 92617-2175 (United States)

    2015-08-01

    Capturing stormwater is becoming a new standard for sustainable urban stormwater management, which can be used to supplement water supply portfolios in water-stressed cities. The key advantage of harvesting stormwater is to use low impact development (LID) systems for treatment to meet water quality requirement for non-potable uses. However, the lack of scientific studies to validate the safety of such practice has limited its adoption. Microbial hazards in stormwater, especially human viruses, represent the primary public health threat. Using adenovirus and norovirus as target pathogens, we investigated the viral health risk associated with a generic scenario of urban stormwater harvesting practice and its application for three non-potable uses: 1) toilet flushing, 2) showering, and 3) food-crop irrigation. The Quantitative Microbial Risk Assessment (QMRA) results showed that food-crop irrigation has the highest annual viral infection risk (median range: 6.8 × 10{sup −4}–9.7 × 10{sup −1} per-person-per-year or pppy), followed by showering (3.6 × 10{sup −7}–4.3 × 10{sup −2} pppy), and toilet flushing (1.1 × 10{sup −7}–1.3 × 10{sup −4} pppy). Disease burden of each stormwater use was ranked in the same order as its viral infection risk: food-crop irrigation > showering > toilet flushing. The median and 95th percentile risk values of toilet-flushing using treated stormwater are below U.S. EPA annual risk benchmark of ≤ 10{sup −4} pppy, whereas the disease burdens of both toilet-flushing and showering are within the WHO recommended disease burdens of ≤ 10{sup −6} DALYs pppy. However, the acceptability of showering risk interpreted based on the U.S. EPA and WHO benchmarks is in disagreement. These results confirm the safety of stormwater application in toilet flushing, but call for further research to fill the data gaps in risk modeling as well as risk benchmarks. - Highlights: • Human health risks for three non-potable uses of treated

  13. Effect of aquifer storage and recovery (ASR) on recovered stormwater quality variability.

    Science.gov (United States)

    Page, D W; Peeters, L; Vanderzalm, J; Barry, K; Gonzalez, D

    2017-06-15

    Aquifer Storage and Recovery (ASR) is increasingly being considered as a means of reusing urban stormwater to supplement available urban water resources. Storage of stormwater in an aquifer has been shown to affect water quality but it has also been claimed that storage will also decrease the stormwater quality variability making for improved predictability and management. This study is the first to document the changes in stormwater quality variability as a result of subsurface storage at four full scale ASR sites using advanced statistical techniques. New methods to examine water quality are required as data is often highly left censored and so traditional measures of variability such as the coefficient of variation are inappropriate. It was observed that for some water quality parameters (most notably E. coli) there was a marked improvement of water quality and a significant decrease in variability at all sites. This means that aquifer storage prior to engineered treatment systems may be advantageous in terms of system design to avoid over engineering. For other parameters such as metal(loids)s and nutrients the trend was less clear due to the numerous processes occurring during storage leading to an increase in variability, especially for geogenic metals and metalloids such as iron and arsenic. Depending upon the specific water quality parameters and end use, use of ASR may not have a dampening effect on stormwater quality variability. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Christopher Walker

    2017-09-01

    Full Text Available 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 catchment ratio was only 0.14%, the results demonstrated a significant removal of both Total Suspended Solids (TSS and Total Phosphorus (TP from the stormwater inflows by the CFW. The efficiency ratios for TSS and TP were 81% and 52%, respectively. While the removal rate for total nitrogen was not significant for the CFW evaluated in this study, the ER was still 17%. However, the ERs for nitrate and nitrogen oxide were both 47%. The study results suggest that it may be possible to increase the pollution removal performance of the CFW by upsizing the system and including intermittent re-aeration zones in the surrounding stormwater pond. The results of this research study clearly demonstrate that CFW can be an effective treatment solution for the removal of pollution from urban stormwater runoff.

  15. Green Roof for Stormwater Management in a Highly Urbanized Area: The Case of Seoul, Korea

    Directory of Open Access Journals (Sweden)

    Muhammad Shafique

    2018-02-01

    Full Text Available Urbanization changes natural pervious surfaces to hard, impervious surfaces such as roads, buildings and roofs. These modifications significantly affect the natural hydrologic cycle by increasing stormwater runoff rates and volume. Under these circumstances, green roofs offer multiple benefits including on-site stormwater management that mimics the natural hydrologic conditions in an urban area. It can retain a large amount of rainwater for a longer time and delay the peak discharge. However, there is very limited research that has been carried out on the retrofitted green roof for stormwater management for South Korean conditions. This study has investigated the performance of retrofitted green roofs for stormwater management in a highly urbanized area of Seoul, the capital city of Korea. In this study, various storm events were monitored and the research results were analyzed to check the performance of the green roof with controlling the runoff in urban areas. Results also allowed us to conclude that the retention mainly depends on the intensity and duration of the rain events. From the analysis, average runoff retention on the green roof was 10% to 60% in different rain events. The application of an extensive green roof provides promising results for stormwater management in the highly urbanized area of Seoul.

  16. Decision Support System (DSS) for MSMA Integrated Stormwater Management Ecohydrology for Sustainable Green Infrastructure

    Science.gov (United States)

    Sidek, L. M.; Mohiyaden, H. A.; Haris, H.; Basri, H.; Muda, Z. C.; Roseli, Z. A.; Norlida, M. D.

    2016-03-01

    Rapid urbanization has known to have several adverse impacts towards hydrological cycle due to increasing impervious surface and degradation of water quality in stormwater runoff. In the past, urban waterways have been confined to narrow river corridors with the channels canalised and concrete and other synthetic materials forming the bed and banks of the river. Apart from that, stormwater pollutants such as litter, debris and sediments in drainage system are common problems that can lead to flooding and the degradation of water quality. To solve this problem, implementing stormwater Best Management Practices (BMPs) proves very promising due to its near natural characteristics and multiple effects on the drainage of stormwater runoff in urban areas. This judgment of using BMPs depends on not only relevant theoretical considerations, but also a large amount of practical experience and the availability of relevant data, as well. To fulfil this task, the so-called Decision Support System (DSS) in MSMA Design Aid and Database system are able to assist engineers and developers in management and improvement of water quantity and quality entering urban rivers from urban regions. This system is also helpful when an expert level judgment procure some repetitive and large amount of cases, like in the planning of stormwater BMPs systems for an entire city catchment. One of the advantages of an expert system is that it provides automation of expert-level judgement using availability of checking tools system.

  17. The influence of temperature and salt on metal and sediment removal in stormwater biofilters.

    Science.gov (United States)

    Søberg, Laila C; Viklander, Maria; Blecken, Godecke-Tobias

    2014-01-01

    Stormwater biofilters are used to treat stormwater runoff. In countries with cold winter climates, biofilters are subject to low temperatures which, in some cases, are combined with potentially high salt concentrations from road de-icing, potentially affecting the biofilter's performance. Since stormwater biofilters have been developed without consideration of their critical winter use, a laboratory study was carried out to evaluate the performance of stormwater biofilters subjected to low and high temperatures, with and without salt. Both factors and their interaction had a significant effect on outflow concentrations and removal percentages. Salt had a negative impact on outflow concentrations, causing lower removal percentages for (especially dissolved) metals, this impact being most pronounced for Cu and Pb. The unrealistic combination of salt with high temperature seemed to further amplify the negative impacts of salt despite the fact that temperature alone did not cause significant differences in outflow concentrations and removal percentages. Still, biofilters showed the ability to treat stormwater efficiently under the simulated winter conditions; outflow concentrations for total metals as a minimum met the class 4 threshold value defined in the Swedish freshwater quality guidelines, while inflow concentrations clearly exceeded the threshold value for class 5. The relatively coarse filter material (which is recommended to facilitate infiltration during winter) did not seem to exacerbate biofilter performance.

  18. Raingarden Soil Bacteria Community Response to Lab Simulated Salt-Enriched Artificial Stormwater

    Science.gov (United States)

    Endreny, T. A.

    2014-12-01

    Cold climate cities with green infrastructure depend on soil bacteria to remove nutrients from road salt-enriched stormwater. Our research examined how bacterial communities in laboratory columns containing bioretention media responded to varying concentrations of salt exposure from artificial stormwater and the effect of bacteria and salt on column effluent concentrations. We used a factorial design with two bacteria treatments (sterile, nonsterile) and three salt concentrations (935, 315, and 80 ppm), including a deionized water control. Columns were repeatedly saturated with stormwater or deionized and then drained throughout 5 wk, with the last week of effluent analyzed for water chemistry. To examine bacterial communities, we extracted DNA from column bioretention media at time 0 and at week 5 and used molecular profiling techniques to examine bacterial community changes. We found that bacterial community taxa changed between time 0 and week 5 and that there was significant separation between taxa among salt treatments. Bacteria evenness was significantly affected by stormwater treatment, but there were no differences in bacterial richness or diversity. Soil bacteria and salt treatments had a significant effect on the effluent concentration of NO3, PO4, Cu, Pb, and Zn based on ANOVA tests. The presence of bacteria reduced effluent NO3 and Zn concentrations by as much as 150 and 25%, respectively, while having a mixed effect on effluent PO4 concentrations. Our results demonstrate how stormwater can affect bacterial communities and how the presence of soil bacteria improves pollutant removal by green infrastructure.

  19. Influence of Modern Stormwater Management Practices on Transport of Road Salt to Surface Waters.

    Science.gov (United States)

    Snodgrass, Joel W; Moore, Joel; Lev, Steven M; Casey, Ryan E; Ownby, David R; Flora, Robert F; Izzo, Grant

    2017-04-18

    Application of road salts in regions with colder climates is leading to ground and surface water contamination. However, we know little about how modern stormwater management practices affect the movement of road salt through urban watersheds. We investigated groundwater contamination and transport of road salts at two stormwater ponds in Baltimore County, Maryland. In association with the ponds, we documented a plume of contaminated groundwater that resulted in Cl - loadings to the adjacent stream of 6574 to 40 008 kg Cl - per winter, depending on winter snowfall. We also monitored Na + and Cl - ion concentrations and the temporal dynamics of conductivity at a range of stream sites in watersheds with and without stormwater management ponds. Streams draining watersheds with stormwater ponds had consistently higher conductivities and Cl - concentrations during base flow conditions and often exhibited greater peaks in Cl - and conductivity associated with winter storms and subsequent melting events, despite the degree of watershed development. Our results indicate that modern stormwater management practices are not protecting surface waters from road salt contamination and suggest they create contaminated plumes of groundwater that deliver Cl - and Na + to streams throughout the year.

  20. Challenges ahead: social and institutional factors influencing sustainable urban stormwater management in Australia.

    Science.gov (United States)

    Brown, R R; Farrelly, M A

    2009-01-01

    In a time of climate uncertainty and drought in Australia, improved urban stormwater quality management practices are required not only for protecting waterway health, but also as a fit-for-purpose supply source. To conceive of urban stormwater as an environmental threat as well as a water supply source requires a substantial shift in our traditional linear supply and wastewater structures towards more hybrid and complex infrastructure systems. To understand what drives and limits treatment technology adoption for stormwater management, over 800 urban water professionals in three Australian capital cities completed an online questionnaire survey in November 2006. Using the conceptual framework of receptivity assessment, the results revealed the professional community to be highly associated with the importance of improving stormwater quality for receiving waterway health, yet they do not consider that politicians share this perspective by placing a substantially lower level of importance on stormwater quality management. Significant acquisition barriers within each city, including institutional arrangements, costs, responsibilities, and regulations and approvals processes were all identified as constraining more sustainable practices. Capacity building programs, fostering greater socio-political capital and developing key demonstration projects with training events are recommended as useful policy interventions for addressing current institutional impediments.

  1. Contributing to the sustainable use of stormwater: the role of pervious pavements.

    Science.gov (United States)

    Jayasuriya, L N N; Kadurupokune, N; Othman, M; Jesse, K

    2007-01-01

    The city of Melbourne, Australia is experiencing a water crisis with potable water storage reservoirs at an all time low. With increasing urbanisation there is an ever increasing need to research and explore sustainable water management initiatives. There is potential to minimise the negative impacts of stormwater runoff and augment dwindling supplies of potable water through adoption of pervious paving technology. The traditional approach to stormwater management has focused on constructing drainage networks to carry stormwater away from developed areas as quickly as possible to avoid the risk of flooding. The main aim of this research project was to establish relationships between rainfall intensity, infiltration rate and pervious pavement runoff and to examine the improvement to stormwater quality after infiltrating through pervious pavements. This paper describes the laboratory experiment set-up to determine the infiltration patterns and stormwater quality improvement for simulated storms precipitating on pervious pavements. Next, the scaling-up of the experimental rig to a field-based trial is explained. Preliminary results from this work are presented to demonstrate the potential benefits of pervious pavements in the Australian landscape.

  2. Heavy metal composition in stormwater and retention in ponds dependent on pond age, design and catchment type

    DEFF Research Database (Denmark)

    Egemose, Sara; Sønderup, Melanie J.; Grudinina, Anna

    2015-01-01

    Heavy metals have toxic effects on flora and fauna in the aquatic environments and are of great concern in stormwater. Heavy metal runoff was studied in 37 stormwater ponds in Denmark with varying heavy metal load, catchment type and pond design. The studied metals were Cu, Cr, Cd, Pb, Ni and Zn....

  3. 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 the explicit objective of protecting or restoring a receiving stream. This article identifies seven major impediments to sustainable urban stormwater management: (1) uncertainties in performance and cost, (2) insufficient engineering standards and guidelines, (3) fragmented responsibilities, (4) lack of institutional capacity, (5) lack of legislative mandate, (6) lack of funding and effective market incentives, and (7) resistance to change. By comparing experiences from Australia and the United States, two developed countries with existing conventional stormwater infrastructure and escalating stream ecosystem degradation, we highlight challenges facing sustainable urban stormwater management and offer several examples of successful, regional WSUD implementation. We conclude by identifying solutions to each of the seven impediments that, when employed separately or in combination, should encourage widespread implementation of WSUD with watershed-based goals to protect human health and safety, and stream ecosystems.

  4. National Stormwater Calculator: A desktop tool that helps users control runoff to promote the natural movement of water

    Science.gov (United States)

    The primary focus of the National Stormwater Calculator (SWC) is to inform site developers on how well they can meet a desired stormwater retention target, but it can also be used by landscapers and homeowners. The SWC shows users how land use decisions and low impact development...

  5. Efficiency of stormwater control measures for combined sewer retrofitting under varying rain conditions: Quantifying the Three Points Approach (3PA)

    DEFF Research Database (Denmark)

    Sørup, Hjalte Jomo Danielsen; Lerer, Sara Maria; Arnbjerg-Nielsen, Karsten

    2016-01-01

    We present a method to assess and communicate the efficiency of stormwater control measures for retrofitting existing urban areas. The tool extends the Three Points Approach to quantitatively distinguish three rainfall domains: (A) rainwater resource utilisation, (B) urban stormwater drainage pipe...

  6. Stormwater harvesting: Improving water security in South Africa's urban areas

    Directory of Open Access Journals (Sweden)

    Lloyd Fisher-Jeffes

    2017-01-01

    Full Text Available The drought experienced in South Africa in 2016 one of the worst in decades has left many urbanised parts of the country with limited access to water, and food production has been affected. If a future water crisis is to be averted, the country needs to conserve current water supplies, reduce its reliance on conventional surface water schemes, and seek alternative sources of water supply. Within urban areas, municipalities must find ways to adapt to, and mitigate the threats from, water insecurity resulting from, inter alia, droughts, climate change and increasing water demand driven by population growth and rising standards of living. Stormwater harvesting (SWH is one possible alternative water resource that could supplement traditional urban water supplies, as well as simultaneously offer a range of social and environmental benefits. We set out three position statements relating to how SWH can: improve water security and increase resilience to climate change in urban areas; prevent frequent flooding; and provide additional benefits to society. We also identify priority research areas for the future in order to target and support the appropriate uptake of SWH in South Africa, including testing the viability of SWH through the use of real-time control and managed aquifer recharge.

  7. The Green Experiment: Cities, Green Stormwater Infrastructure, and Sustainability

    Directory of Open Access Journals (Sweden)

    Christopher M. Chini

    2017-01-01

    Full Text Available Green infrastructure is a unique combination of economic, social, and environmental goals and benefits that requires an adaptable framework for planning, implementing, and evaluating. In this study, we propose an experimental framework for policy, implementation, and subsequent evaluation of green stormwater infrastructure within the context of sociotechnical systems and urban experimentation. Sociotechnical systems describe the interaction of complex systems with quantitative and qualitative impacts. Urban experimentation—traditionally referencing climate change programs and their impacts—is a process of evaluating city programs as if in a laboratory setting with hypotheses and evaluated results. We combine these two concepts into a singular framework creating a policy feedback cycle (PFC for green infrastructure to evaluate municipal green infrastructure plans as an experimental process within the context of a sociotechnical system. After proposing and discussing the PFC, we utilize the tool to research and evaluate the green infrastructure programs of 27 municipalities across the United States. Results indicate that green infrastructure plans should incorporate community involvement and communication, evaluation based on project motivation, and an iterative process for knowledge production. We suggest knowledge brokers as a key resource in connecting the evaluation stage of the feedback cycle to the policy phase. We identify three important needs for green infrastructure experimentation: (i a fluid definition of green infrastructure in policy; (ii maintenance and evaluation components of a green infrastructure plan; and (iii communication of the plan to the community.

  8. Stormwater Pollution Prevention Plan - TA-60 Asphalt Batch Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, Leonard Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-31

    This Storm Water Pollution Prevention Plan (SWPPP) was developed in accordance with the provisions of the Clean Water Act (33 U.S.C. §§1251 et seq., as amended), and the Multi-Sector General Permit for Storm Water Discharges Associated with Industrial Activity (U.S. EPA, June 2015) issued by the U.S. Environmental Protection Agency (EPA) for the National Pollutant Discharge Elimination System (NPDES) and using the industry specific permit requirements for Sector P-Land Transportation and Warehousing as a guide. This SWPPP applies to discharges of stormwater from the operational areas of the TA-60-01 Asphalt Batch Plant at Los Alamos National Laboratory. Los Alamos National Laboratory (also referred to as LANL or the “Laboratory”) is owned by the Department of Energy (DOE), and is operated by Los Alamos National Security, LLC (LANS). Throughout this document, the term “facility” refers to the TA-60 Asphalt Batch Plant and associated areas. The current permit expires at midnight on June 4, 2020.

  9. Stormwater Pollution Prevention Plan - TA-60 Material Recycling Facility

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, Leonard Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-31

    This Storm Water Pollution Prevention Plan (SWPPP) was developed in accordance with the provisions of the Clean Water Act (33 U.S.C. §§1251 et seq., as amended), and the Multi-Sector General Permit for Storm Water Discharges Associated with Industrial Activity (U.S. EPA, June 2015) issued by the U.S. Environmental Protection Agency (EPA) for the National Pollutant Discharge Elimination System (NPDES) and using the industry specific permit requirements for Sector P-Land Transportation and Warehousing as a guide. This SWPPP applies to discharges of stormwater from the operational areas of the TA- 60 Material Recycling Facility at Los Alamos National Laboratory. Los Alamos National Laboratory (also referred to as LANL or the “Laboratory”) is owned by the Department of Energy (DOE), and is operated by Los Alamos National Security, LLC (LANS). Throughout this document, the term “facility” refers to the TA-60 Material Recycling Facility. The current permit expires at midnight on June 4, 2020.

  10. Retarded hippocampal development following prenatal exposure to ...

    African Journals Online (AJOL)

    Results: Rats in Group A showed no implantation, rats in Group B had abortion on the 7th day after administration, and rats in Group C gave birth with their litters showing retarded hippocampus development and neural degeneration and rats in Group D (control) showed normal development. Conclusion: Ethanolic extract of ...

  11. Opitz C syndrome: Trigonocephaly, mental retardation and ...

    African Journals Online (AJOL)

    J.A. Avina Fierro

    2015-06-09

    Jun 9, 2015 ... Abstract We describe a 4-year-old female child with a dysmorphic and neurological syndrome of trigonocephaly, mental and psychomotor retardation and dysmorphic facial features. The anoma- lies of the face were the following: slight upward palpebral fissures, ocular hypertelorism, depressed.

  12. Abandoning the Myth of Mental Retardation

    Science.gov (United States)

    Smith, J. David

    2003-01-01

    In this article, the author talks about the concept underlying the term metal retardation and the effort to define it in a way that is scientifically accurate and in a way that promotes greater sensitivity to the needs of people described by the term which has been continuous for centuries. The author states that a scientifically sound and…

  13. Unveiling causes for growth retardation in piglets

    NARCIS (Netherlands)

    Paredes Escobar, S.

    2014-01-01

    The evolution of hyper‐prolific sow breeds has led to a higher number of piglets born per sow per year. This increase in litter size has enlarged the number of light weight (or growth retarded) piglets, increased pre‐weaning mortality and heterogeneity at the end of the nursery phase (ten weeks of

  14. Euthanasia and Mental Retardation: Suggesting the Unthinkable.

    Science.gov (United States)

    Hollander, Russell

    1989-01-01

    The article examines current opinions toward euthanasia of persons with mental retardation in light of the history of public and professional attitudes. It also discusses the rejection of euthanasia on moral and religious grounds, and notes the use of lifelong incarceration, based on eugenics principles, to accomplish similar ends. (DB)

  15. Flexible PVC flame retarded with expandable graphite

    CSIR Research Space (South Africa)

    Focke, WW

    2014-02-01

    Full Text Available The utility of expandable graphite as a flame retardant for PVC, plasticized with 60 phr of a phosphate ester, was investigated. Cone calorimeter results, at a radiant flux of 35 kW m 2, revealed that adding only 5 wt.% expandable graphite lowered...

  16. Hormonal activities of new brominated flame retardants

    Czech Academy of Sciences Publication Activity Database

    Ezechiáš, Martin; Svobodová, Kateřina; Cajthaml, Tomáš

    2012-01-01

    Roč. 87, č. 7 (2012), s. 820-824 ISSN 0045-6535 R&D Projects: GA ČR GA104/09/0694 Institutional research plan: CEZ:AV0Z50200510 Keywords : Brominated flame retardants * 2,4,6-Tribromophenol * Endocrine disruptors Subject RIV: EE - Microbiology, Virology Impact factor: 3.137, year: 2012

  17. Opitz C syndrome: Trigonocephaly, mental retardation and ...

    African Journals Online (AJOL)

    We describe a 4-year-old female child with a dysmorphic and neurological syndrome of trigonocephaly, mental and psychomotor retardation and dysmorphic facial ... The patient had important cerebral anomalies with diffuse alterations in white matter that caused developmental delay with verbal and nonverbal disabilities ...

  18. Stability for retarded functional differential equations

    Czech Academy of Sciences Publication Activity Database

    Federson, M.; Schwabik, Štefan

    2008-01-01

    Roč. 60, č. 1 (2008), s. 121-140 ISSN 0041-5995 R&D Projects: GA AV ČR IAA100190702 Institutional research plan: CEZ:AV0Z10190503 Keywords : retarded functional differential equation * generalized differential equation * stability Subject RIV: BA - General Mathematics

  19. PENETRATING KERATOPLASTY IN MENTALLY RETARDED PATIENTS

    Directory of Open Access Journals (Sweden)

    Dušica Pahor

    2002-12-01

    Full Text Available Background. Penetrating keratoplasty (PK is rarely performed in mentally retarded patients, first of all because of numerous complications after surgery such as inflammation, self-inflicted injury, injury and because of difficult post-operative treatment. The aim of this study was to present the success of PK in this patients. In 16 years (from May 1984 to May 2000 201 PK were performed, but only three in mentally retarded patients.Methods. We present three cases of PK in mentally retarded patients. All the patients were men. They were 14, 16 and 27 year old. The indication for PK were in two cases acute keratoconus and in one case acute keratoglobus. The mean followup was 24.6 months. Trepanation was made with rotor threpin and donor material was sutured using single continuous 10-0 nylon suture.Results. In two cases keratoplasties stayed clear. Visual acuities were 0,4 and 0,5. In one patient with very aggressive behaviour graft failure developed with significant corneal vascularisation. Re-keratoplasty was not performed.Conclusions. Adequate post-operative care following PK in mentally retarded patients is the most important factor for the success of transplantation. The indication for the surgery must be made very carefully especially in self-aggressive patients in residential care.

  20. Skin mastocytosis, hearing loss and mental retardation

    NARCIS (Netherlands)

    Hennekam, R. C.; Beemer, F. A.

    1992-01-01

    A girl with skin mastocytosis, hearing loss, microcephaly, mild dysmorphic features and severe mental retardation is described. The symptoms of the child resemble those reported in 1990 by Wolach et al. in another patient sufficiently to suspect the same entity in both. Inheritance may be autosomal

  1. Brominated flame retardants and endocrine disruption

    NARCIS (Netherlands)

    Vos, J.G.; Becher, G.; Berg, van den M.; Boer, de J.; Leonards, P.E.G.

    2003-01-01

    From an environmental point of view, an increasing important group of organohalogen compounds are the brominated flame retardants (BFRs), which are widely used in polymers and textiles and applied in construction materials, furniture, and electronic equipment. BFRs with the highest production volume

  2. Brominated flame retardants and endocrine disruption

    NARCIS (Netherlands)

    Vos, Joseph G.; Becher, Georg; Van Den Berg, Martin; Leonards, Pim E G

    2003-01-01

    From an environmental point of view, an increasing important group of organo-halogen compounds are the brominated flame retardants (BFRs), which are widely used in polymers and textiles and applied in construction materials, furniture, and electronic equipment. BFRs with the highest production

  3. Flame retardant cotton barrier nonwovens for mattresses

    Science.gov (United States)

    According to regulation CPSC 16 CFR 1633, every new residential mattress sold in the United States since July 2007 must resist ignition by open flame. An environmentally benign “green”, inexpensive way to meet this regulation is to use a low-cost flame retardant (FR) barrier fabric. In this study, a...

  4. Preparation of Flame Retardant Modified with Titanate for Asphalt Binder

    Directory of Open Access Journals (Sweden)

    Bo Li

    2014-01-01

    Full Text Available Improving the compatibility between flame retardant and asphalt is a difficult task due to the complex nature of the materials. This study explores a low dosage compound flame retardant and seeks to improve the compatibility between flame retardants and asphalt. An orthogonal experiment was designed taking magnesium hydroxide, ammonium polyphosphate, and melamine as factors. The oil absorption and activation index were tested to determine the effect of titanate on the flame retardant additive. The pavement performance test was conducted to evaluate the effect of the flame retardant additive. Oxygen index test was conducted to confirm the effect of flame retardant on flame ability of asphalt binder. The results of this study showed that the new composite flame retardant is more effective in improving the compatibility between flame retardant and asphalt and reducing the limiting oxygen index of asphalt binder tested in this study.

  5. Daphnid life cycle response to new generation of flame retardants

    NARCIS (Netherlands)

    Waaijers, S.L.; Bleyenberg, T.E.; Dits, A; Schoorl, M.; Schütt, J; Kools, S.A.E.; de Voogt, P.; Admiraal, W.; Parsons, J.R.; Kraak, M.H.S.

    2013-01-01

    Relatively hazardous brominated flame retardants (BFRs) are currently substituted with halogen-free flame retardants (HFFRs). Consequently, information on their persistence, bioaccumulation and toxicity (PBT) is urgently needed. Therefore, we investigated the chronic toxicity to the water flea

  6. An Open-Source Auto-Calibration Routine Supporting the Stormwater Management Model

    Science.gov (United States)

    Tiernan, E. D.; Hodges, B. R.

    2017-12-01

    The stormwater management model (SWMM) is a clustered model that relies on subcatchment-averaged parameter assignments to correctly capture catchment stormwater runoff behavior. Model calibration is considered a critical step for SWMM performance, an arduous task that most stormwater management designers undertake manually. This research presents an open-source, automated calibration routine that increases the efficiency and accuracy of the model calibration process. The routine makes use of a preliminary sensitivity analysis to reduce the dimensions of the parameter space, at which point a multi-objective function, genetic algorithm (modified Non-dominated Sorting Genetic Algorithm II) determines the Pareto front for the objective functions within the parameter space. The solutions on this Pareto front represent the optimized parameter value sets for the catchment behavior that could not have been reasonably obtained through manual calibration.

  7. Design procedure for pollutant loadings and impacts for highway stormwater runoff (Macintosh version) (for microcomputers). Software

    International Nuclear Information System (INIS)

    1990-01-01

    The interactive computer program was developed to make a user friendly procedure for the personal computer for calculations and guidance to make estimations of pollutant loadings and impacts from highway stormwater runoff which are presented in the Publication FHWA-RD-88-006, Pollutant Loadings and Impacts from Highway Stormwater Runoff, Volume I: Design Procedure. The computer program is for the evaluation of the water quality impact from highway stormwater runoff to a lake or a stream from a specific highway site considering the necessary rainfall data and geographic site situation. The evaluation considers whether or not the resulting water quality conditions can cause a problem as indicated by the violations of water quality criteria or objectives

  8. Design procedure for pollutant loadings and impacts for highway stormwater runoff (IBM version) (for microcomputers). Software

    International Nuclear Information System (INIS)

    1990-01-01

    The interactive computer program was developed to make a user friendly procedure for the personal computer for calculations and guidance to make estimations of pollutant loadings and impacts from highway stormwater runoff which are presented in the Publication FHWA-RD-88-006, Pollutant Loadings and Impacts from Highway Stormwater Runoff, Volume I: Design Procedure. The computer program is for the evaluation of the water quality impact from highway stormwater runoff to a lake or a stream from a specific highway site considering the necessary rainfall data and geographic site situation. The evaluation considers whether or not the resulting water quality conditions can cause a problem as indicated by the violations of water quality criteria or objectives

  9. 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.

  10. Application of a risk management framework to a drinking water supply augmented by stormwater recharge.

    Science.gov (United States)

    Vanderzalm, J L; Page, D W; Dillon, P J

    2011-01-01

    The Blue Lake is an important water resource for the city of Mount Gambier and the surrounding region, primarily as the drinking water supply source, but also as a tourist attraction. Mount Gambier's stormwater is discharged directly via drainage wells into the unconfined, karstic Gambier Limestone aquifer, which in turn provides the majority of recharge to Blue Lake. Discharge of urban runoff to the aquifer commenced in the 1800s as a means of stormwater management, but is now recognised as contributing to the drinking water supply in Blue Lake. Recently, guidelines for managing the risks associated with water recycling and augmenting drinking water supplies have been developed. This paper examines the organic chemical hazards associated with a stormwater to potable recycling scheme as an example of the current risk management framework.

  11. Simulating future trends in urban stormwater quality for changing climate, urban land use and environmental controls.

    Science.gov (United States)

    Borris, Matthias; Viklander, Maria; Gustafsson, Anna-Maria; Marsalek, Jiri

    2013-01-01

    The effects of climatic changes, progressing urbanization and improved environmental controls on the simulated urban stormwater quality in a northern Sweden community were studied. Future scenarios accounting for those changes were developed and their effects simulated with the Storm Water Management Model (SWMM). It was observed that the simulated stormwater quality was highly sensitive to the scenarios, mimicking progressing urbanization with varying catchment imperviousness and area. Thus, land use change was identified as one of the most influential factors and in some scenarios, urban growth caused changes in runoff quantity and quality exceeding those caused by a changing climate. Adaptation measures, including the reduction of directly connected impervious surfaces (DCIS) through the integration of more green spaces into the urban landscape, or disconnection of DCIS were effective in reducing runoff volume and pollutant loads. Furthermore, pollutant source control measures, including material substitution, were effective in reducing pollutant loads and significantly improving stormwater quality.

  12. Improving the Hydraulic Performance of Stormwater Infiltration Systems in Clay Tills

    DEFF Research Database (Denmark)

    Bockhorn, Britta

    Many cities of the Northern Hemisphere are covered by low permeable clay tills, which pose a challenge for stormwater infiltration practices. However, clay tills are amongst the most heterogeneous types of sediments and hydraulic conductivities can vary by several orders of magnitude. This Ph......D study was initiated with the objective to test and evaluate if the hydraulic performance of stormwater infiltration systems can be significantly improved if the site-specific geological heterogeneity is incorporated into the design and siting of such systems. The assessment is based on different field...... investigations on two typical Danish clay till sites, and one modeling study with the integrated surface water and groundwater model HydroGeoSphere. The saturated hydraulic conductivity (Ksat) is the most critical soil physical parameter when it comes to sizing stormwater infiltration systems. In the first study...

  13. Effectiveness of Flame Retardants in TufFoam.

    Energy Technology Data Exchange (ETDEWEB)

    Abelow, Alexis Elizabeth [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Nissen, April [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Massey, Lee Taylor [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Whinnery, LeRoy L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2017-12-01

    An investigation of polyurethane foam filled with known flame retardant fillers including hydroxides, melamine, phosphate-containing compounds, and melamine phosphates was carried out to produce a low-cost material with high flame retardant efficiency. The impact of flame retardant fillers on the physical properties such a s composite foam density, glass transition temperature, storage modulus, and thermal expansion of composite foams was investigated with the goal of synthesizing a robust rigid foam with excellent flame retardant properties.

  14. Heavy metal contamination of vegetables irrigated by urban stormwater: a matter of time?

    Directory of Open Access Journals (Sweden)

    Minna Tom

    Full Text Available Urban stormwater is a crucial resource at a time when climate change and population growth threaten freshwater supplies; but there are health risks from contaminants, such as toxic metals. It is vitally important to understand how to use this resource safely and responsibly. Our study investigated the extent of metal contamination in vegetable crops irrigated with stormwater under short- and long-term conditions. We created artificially aged gardens by adding metal-contaminated sediment to soil, simulating accumulation of metals in the soil from irrigation with raw stormwater over zero, five and ten years. Our crops--French bean (Phaseolus vulgaris, kale (Brassica oleracea var. acephala, and beetroot (Beta vulgaris--were irrigated twice a week for 11 weeks, with either synthetic stormwater or potable water. They were then tested for concentrations of Cd, Cr, Pb, Cu and Zn. An accumulation of Pb was the most marked sign of contamination, with six of nine French bean and seven of nine beetroot leaf samples breaching Australia's existing guidelines. Metal concentration in a crop tended to increase with the effective age of the garden; but importantly, its rate of increase did not match the rate of increase in the soil. Our study also highlighted differences in sensitivity between different crop types. French bean demonstrated the highest levels of uptake, while kale displayed restrictive behaviour. Our study makes it clear: irrigation with stormwater is indeed feasible, as long as appropriate crops are selected and media are frequently turned over. We have also shown that an understanding of such risks yields meaningful information on appropriate safeguards. A holistic approach is needed--to account for all routes to toxic metal exposure, including especially Pb. A major outcome of our study is critical information for minimising health risks from stormwater irrigation of crops.

  15. Phosphorus flame retardants: Properties, production, environmental occurrence, toxicity and analysis

    NARCIS (Netherlands)

    van der Veen, I.; de Boer, J.

    2012-01-01

    Since the ban on some brominated flame retardants (BFRs), phosphorus flame retardants (PFRs), which were responsible for 20% of the flame retardant (FR) consumption in 2006 in Europe, are often proposed as alternatives for BFRs. PFRs can be divided in three main groups, inorganic, organic and

  16. Cardiovascular Risk Factor Levels in Adults with Mental Retardation.

    Science.gov (United States)

    Rimmer, James H.; And Others

    1994-01-01

    Comparison of cardiovascular risk factors (blood lipids, obesity, and smoking) in 329 adults with mental retardation residing in various settings with subjects in the Framingham Offspring Study found that adults with mental retardation had cardiovascular risk profiles similar to those of individuals without mental retardation. (Author/DB)

  17. Caring for children with mental retardation: The experiences of ...

    African Journals Online (AJOL)

    Caring for children with mental retardation at home requires great patience and understanding. Mothers often experience difficulties adjusting to the fact that their children are mentally retarded and that it cannot be cured. This study investigated the experiences of mothers caring for children with mental retardation.

  18. Preparation and characterizations of flame retardant polyamide 66 fiber

    Science.gov (United States)

    Li, Y. Y.; Liu, K.; Xiao, R.

    2017-06-01

    The polyamide 66 (PA66) is one of the most important thermoplastic materials, but it has the drawback of flammability. So the flame retardant PA66 was prepared by condensation polymerization using nylon salt and DOPO-based flame retardant in this paper. Then the flame retardant PA66 fiber was manufactured via melt spinning. The properties of flame retardant PA66 and flame retardant PA66 fiber were investigated by relative viscosity, differential scanning calorimetry (DSC), tensile test, vertical burning test (UL94) and limiting oxygen index (LOI) test. Although the loading of the DOPO-based flame retardant decreased the molecular weight, the melting temperature, the crystallinity and the mechanical properties of flame retardant PA66, the flame retardancy properties improved. The flame retardant PA66 loaded with 5.5 wt% of DOPO-based flame retardant can achieve a UL94 V-0 rating with a LOI value of 32.9%. The tenacity at break decreased from 4.51 cN·dtex-1 for PA66 fiber to 2.82 cN·dtex-1 for flame retardant PA66 fiber which still satisfied the requirements for fabrics. The flame retardant PA66 fiber expanded the application of PA66 materials which had a broad developing prospect.

  19. Older Mentally Retarded Persons: Demographic Profile and Service Requirements.

    Science.gov (United States)

    Seltzer, Marsha Mailick

    An overview is presented on current knowledge about elderly mentally retarded persons. Definitional and incidence issues are addressed, and support is voiced for use of a lower cut-off for the beginning of old age among the retarded than for the general population. Conflicting findings of age-related differences in mentally retarded adults are…

  20. Anxious-retarded depression: relation to family history of depression

    NARCIS (Netherlands)

    de Winter, Remco F. P.; Zwinderman, Koos H.; Goekoop, Jaap G.

    2004-01-01

    Anxious-retarded depression is a two-dimensionally defined subcategory of depression based on high scores for both anxiety and retardation. The anxious-retarded subcategory is related to melancholia as defined by DSM-IV. Patients with this diagnosis exhibit elevated plasma arginine vasopressin (AVP)

  1. Stigma Perception and Social Adjustment of Mentally Retarded Persons.

    Science.gov (United States)

    Gibbons, Frederick X.

    Two studies attempted to assess the effect of the mental retardation label on the formation of social impressions in mentally retarded (MR) adults. In the first study, 123 mildly retarded students, half of whom were institutionalized were interviewed and asked to respond to questions about individuals pictured (some of whom were labeled as MR).…

  2. Flame retardancy and thermal degradation of cotton textiles based on UV-curable flame retardant coatings

    International Nuclear Information System (INIS)

    Xing, Weiyi; Jie, Ganxin; Song, Lei; Hu, Shuang; Lv, Xiaoqi; Wang, Xin; Hu, Yuan

    2011-01-01

    The flame retardant coatings were prepared through UV-curable technique using tri(acryloyloxyethyl) phosphate (TAEP) and triglycidyl isocyanurate acrylate (TGICA). Results from FTIR-ATR spectroscopy and scanning electron microscopy (SEM) showed that flame retardant coatings were successfully coated onto the surface of cotton fabrics. The flame retardancy of the treated fabrics was studied by Micro-scale Combustion Calorimeter (MCC) and limited oxygen index (LOI). The cottons coated flame retardant coatings had the lower peak heat release rate (PHRR), heat release capacity (HRC), total heat of combustion (THC) and higher LOI value compared with untreated cotton. The results from TGA test showed that the flame retardant coatings lowered the decomposition temperature of treated fabric. The thermal decomposition of cottons was monitored by real time FTIR analysis and thermogravimetric analysis/infrared spectrometry (TGA-IR). The enhanced flame retardant action might be caused by thermal decomposition of TAEP structure, producing acidic intermediates, which could react with fabrics to alter its thermal decomposition process.

  3. Assessment of public health risk associated with viral contamination in harvested urban stormwater for domestic applications.

    Science.gov (United States)

    Lim, Keah-Ying; Hamilton, Andrew J; Jiang, Sunny C

    2015-08-01

    Capturing stormwater is becoming a new standard for sustainable urban stormwater management, which can be used to supplement water supply portfolios in water-stressed cities. The key advantage of harvesting stormwater is to use low impact development (LID) systems for treatment to meet water quality requirement for non-potable uses. However, the lack of scientific studies to validate the safety of such practice has limited its adoption. Microbial hazards in stormwater, especially human viruses, represent the primary public health threat. Using adenovirus and norovirus as target pathogens, we investigated the viral health risk associated with a generic scenario of urban stormwater harvesting practice and its application for three non-potable uses: 1) toilet flushing, 2) showering, and 3) food-crop irrigation. The Quantitative Microbial Risk Assessment (QMRA) results showed that food-crop irrigation has the highest annual viral infection risk (median range: 6.8×10(-4)-9.7×10(-1) per-person-per-year or pppy), followed by showering (3.6×10(-7)-4.3×10(-2)pppy), and toilet flushing (1.1×10(-7)-1.3×10(-4)pppy). Disease burden of each stormwater use was ranked in the same order as its viral infection risk: food-crop irrigation>showering>toilet flushing. The median and 95th percentile risk values of toilet-flushing using treated stormwater are below U.S. EPA annual risk benchmark of ≤10(-4)pppy, whereas the disease burdens of both toilet-flushing and showering are within the WHO recommended disease burdens of ≤10(-6)DALYspppy. However, the acceptability of showering risk interpreted based on the U.S. EPA and WHO benchmarks is in disagreement. These results confirm the safety of stormwater application in toilet flushing, but call for further research to fill the data gaps in risk modeling as well as risk benchmarks. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. 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...

  5. Review on the quality of sediments from the stormwater drainage system in the urban area

    Directory of Open Access Journals (Sweden)

    Nawrot Nicole

    2017-01-01

    Full Text Available The main task of the stormwater drainage system (SDS is a safe drainage of rainwater and snowmelt from the urban area to the receiver. The flow of rain water in the drainage pipes is directly related with the formation of sediments in the whole stormwater system. In addition, pollutants from land runoff get adsorbed to the sediments. The sludge is mainly formed in those elements of SDS, wherein the flow conditions allow for sedimentation. This article provides an overview of the literature concerning the characteristics of sediments from SDS, with a particular focus on heavy metals in sediments deposited in the urban catchment area.

  6. Green stormwater infrastructure eco-planning and development on the regional scale: a case study of Shanghai Lingang New City, East China

    Science.gov (United States)

    Xu, Haishun; Chen, Liang; Zhao, Bing; Zhang, Qiuzhuo; Cai, Yongli

    2016-06-01

    Urban underlying surface has been greatly changed with rapid urbanization, considered to be one of the major causes for the destruction of urban natural hydrological processes. This has imposed a huge challenge for stormwater management in cities. There has been a shift from gray water management to green stormwater management thinking. The green stormwater infrastructure (GSI) is regarded as an effective and cost-efficient stormwater management eco-landscape approach. China's GSI practice and the development of its theoretical framework are still in the initial stage. This paper presents an innovative framework for stormwater management, integrating green stormwater infrastructure and landscape security patterns on a regional scale based on an urban master plan. The core concept of green stormwater infrastructure eco-planning is to form an interconnected GSI network (i.e., stormwater management landscape security pattern) which consists of the location, portion, size, layout, and structure of GSI so as to efficiently safeguard natural hydrological processes. Shanghai Lingang New City, a satellite new town of Shanghai, China was selected as a case study for GSI studies. Simulation analyses of hydrological processes were carried out to identify the critical significant landscape nodes in the highpriority watersheds for stormwater management. GSI should be planned and implemented in these identified landscape nodes. The comprehensive stormwater management landscape security pattern of Shanghai Lingang New City is designed with consideration of flood control, stormwater control, runoff reduction, water quality protection, and rainwater utilization objectives which could provide guidelines for smart growth and sustainable development of this city.

  7. Effect of the method of estimation of soil saturated hydraulic conductivity with regards to the design of stormwater infiltration trenches

    Science.gov (United States)

    Paiva coutinho, Artur; Predelus, Dieuseul; Lassabatere, Laurent; Ben Slimene, Erij; Celso Dantas Antonino, Antonio; Winiarski, Thierry; Joaquim da Silva Pereira Cabral, Jaime; Angulo-Jaramillo, Rafael

    2014-05-01

    Best management practices are based on the infiltration of stormwater (e.g. infiltration into basins or trenches) to reduce the risk of flooding of urban areas. Proper estimations of saturated hydraulic conductivity of the vadose zone are required to avoid inappropriate design of infiltration devices. This article aims at assessing (i) the method-dependency of the estimation of soils saturated hydraulic conductivity and (ii) the consequences of such dependency on the design of infiltration trenches. This is illustrated for the specific case of an infiltration trench to be constructed to receive stormwater from a specific parking surface, 250 m2 in area, in Recife (Brazil). Water infiltration experiments were conducted according to the Beerkan Method, i.e. application of a zero water pressure head through a disc source (D=15 cm) and measures of the amount of infiltrated water with time. Saturated hydraulic conductivity estimates are derived from the analysis of these infiltration tests using several different conceptual approaches: one-dimensional models of Horton(1933) and Philip(1957), three-dimensional methods recently developed (Lassabatere et al., 2006, Wu et al., 1999, and Bagarello et al., 2013) and direct 3-dimensional numerical inversion. The estimations for saturated hydraulic conductivity ranged between 65.5 mm/h and 94 mm/h for one-dimensional methods, whereas using three-dimensional methods saturated hydraulic conductivity ranged between 15.6 mm/h and 50 mm/h. These results shows the need for accounting for 3D geometry, and more generally, the physics of water infiltration in soils, if a proper characterization of soil saturated hydraulic conductivity is targeted. In a second step, each estimate of the saturated hydraulic conductivity was used to calculate the stormwater to be stored in the studied trench for several rainfall events of recurrence intervals of 2 to 25 years. The calculation of these volumes showed a great sensitivity with regards to the

  8. Emerging and historical halogenated flame retardants in fish samples from Iberian rivers.

    Science.gov (United States)

    Santín, G; Barón, E; Eljarrat, E; Barceló, D

    2013-12-15

    Forty-eight fish samples from the Llobregat, Ebro, Júcar and Guadalquivir river basins (Spain), were analyzed for polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), hexabromobenzene (HBB), pentabromoethylbenzene (PBEB) and halogenated norbornenes (HNs). The most contaminated river basin was the Llobregat, followed by the Ebro, Júcar and Guadalquivir for almost every analyzed contaminant. Most abundant PBDE congener was BDE-47 (BDL-396 ng/g lw) and the most abundant halogenated norbornene was Dechlorane-602 (BQL-174 ng/g lw). Fanti was calculated to determine the different bioaccumulation/biodegradation of syn-DP and anti-DP. Biota to sediment accumulation factor was calculated in order to compare the bioaccumulation capacity of emerging flame retardants with that of "classical" PBDEs. It was found that bioaccumulation of halogenated norbornenes is lower than that of PBDEs. BDE-99, HBB, PBEB and Dechlorane-604 were not detected in any sample. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Live diatoms as indicators of urban stormwater runoff.

    Science.gov (United States)

    Gillett, Nadia D; Oudsema, Maggie E; Steinman, Alan D

    2017-01-01

    Diatom bioassessment of streams/rivers does not distinguish between live (cells with intact chloroplasts) and dead (empty cells) individuals, even though most diatom samples collected from the field will be composed of a mixture of both. This study aimed to evaluate whether percentage of live diatoms (PLD), live diatom density and chlorophyll a, and diatom species compositions can be used as indicators of hydrologic disturbance in an urban stream. We deployed artificial substrates on a monthly basis and collected periphyton samples weekly over the course of one calendar year (n = 182) in three tributaries of urbanized Ruddiman Creek (Michigan, USA). We also collected samples before and after six major storm events (>0.5 cm rain). We found no temporal patterns in PLD (Mann-Kendall test p > 0.05) or species composition (non-metric multidimensional scaling (NMDS) ordination), which may be explained by a diatom composition already tolerant to frequent disturbance. There was no difference in PLD before and after storm events, which might partially be explained by their disturbance resistance due to different assemblage ages (1, 2, and 4 weeks old) before the storms. High flow had differential effects on diatom species; loosely attached Navicula and Nitzschia species were more easily removed compared to stalk-forming Gomphonema parvulum. The most important environmental variable that was found to affect live diatom density and chlorophyll was stream width, which has an indirect effect (as a measure of discharge) on periphyton assemblages. In conclusion, PLD was found to be unsuitable metric for assessing stormwater runoff in urban streams where periphyton may not have enough time to form mature communities.

  10. 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

    concentrations. Similar results are expected for other particle bound pollutants including metals and slowly biodegradable organic substances such as PAH. Acute toxicity impacts to downstream surface waters seem to be only slightly affected. A minor increase in yearly loads of sediments and particle......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...

  11. Psychomotor Retardation in untreated depressed elderly

    Directory of Open Access Journals (Sweden)

    Lieve Lia Beheydt

    2015-01-01

    Full Text Available Background: Psychomotor retardation (PR is one of the core features in depression according to 17 DSM V1, but also aging in itself causes cognitive and psychomotor slowing. This is the first study 18 investigating psychomotor retardation in relation to cognitive functioning and to the concomitant 19 effect of depression and aging in a geriatric population ruling out contending effects of psychotropic 20 medication. Methods: A group of 28 non-demented depressed elderly is compared to a matched 21 control group of 20 healthy elderly. All participants underwent a test battery containing clinical 22 depression measures, cognitive measures of processing speed, executive function and memory, 23 clinical ratings of psychomotor retardation and objective computerized fine motor skill-tests. 24 Statistical analysis consisted of a General Linear Method (GLM multivariate analysis of variance to 25 compare the clinical, cognitive and psychomotor outcomes of the two groups. Results: Patients 26 performed worse on all clinical, cognitive and psychomotor retardation measures. Both groups 27 showed an effect of cognitive load on fine motor function but the influence was significantly larger 28 for patients than for healthy elderly except for the initiation time. Limitations: due to the restrictive 29 inclusion criteria, only a relatively limited sample size could be obtained. Conclusion: With a 30 medication free sample, an additive effect of depression and aging on cognition and PR in geriatric 31 patients was found,. As this effect was independent of demand of effort (by varying the cognitive 32 load, it was apparently not a motivational slowing effect of depression.

  12. 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.

  13. Who governs climate adaptation? Getting green roofs for stormwater retention off the ground

    NARCIS (Netherlands)

    Mees, H.L.P.; Driessen, P.P.J.; Runhaar, H.A.C.; Stamatelos, J.

    2013-01-01

    Green roofs are an innovative solution for urban stormwater management. This paper examines governance arrangements for green roofs as a ‘no-regrets’ climate adaptation measure in five cities. We analysed who governs green roofs, why and with what outcome. Our results show that hierarchical and

  14. Laboratory Studies on Granular Filters and Their Relationship to Geotextiles for Stormwater Pollutant Reduction

    Directory of Open Access Journals (Sweden)

    Parneet Paul

    2015-04-01

    Full Text Available Applications of geotextiles within tertiary stormwater treatment systems and for stormwater infiltration can provide a substrate for biofilm formation, enabling biological treatment of contaminants. Geotextiles can serve as an efficient part of stormwater filtration within the urban water environment. The project assessed the applications of three experimental granular filters as a sustainable urban drainage system (SUDS for the decomposition of organic pollutant loading present in stormwater. The three filter rigs were packed with alternating layers of filter media consisting of gravel, pea gravel, sand and either a single, double or no layer of geotextile membrane. A nonwoven geotextile was layered within the filter media. The hydraulic loading capacity for the three filters matched that commonly used with conventional sand filters systems. Water quality parameters were quantified by measuring suspended solids, chemical oxygen demand, dissolved oxygen, pH, nitrate-nitrogen, and phosphate concentrations. It was found that Filter Rig No. 3 (upper and lower geotextile membrane and Filter Rig No. 2 (single geotextile membrane had a significant statistical difference in treatment performance from Filter Rig No. 1 (no geotextile membrane.

  15. 76 FR 22882 - Draft National Pollutant Discharge Elimination System (NPDES) General Permit for Stormwater...

    Science.gov (United States)

    2011-04-25

    ..., building products, construction wastes, trash, landscape materials, fertilizers, pesticides, herbicides, detergents, sanitary waste, and other materials present on the site to precipitation and to stormwater; and 3... Home Builders (NAHB) filed a motion for clarification (which EPA did not oppose) asking the Court to (1...

  16. 78 FR 72676 - Draft National Pollutant Discharge Elimination System (NPDES) General Permit for Stormwater...

    Science.gov (United States)

    2013-12-03

    ... Discharges From Industrial Activities; Extension of Comment Period AGENCY: Environmental Protection Agency... Pollutant Discharge Elimination System (NPDES) general permit for stormwater discharges from industrial... docket and made available on the Internet. If you submit an electronic comment, the EPA recommends that...

  17. Transport and fate of viruses in sediment and stormwater from a managed aquifer recharge site

    Science.gov (United States)

    Enteric viruses are one of the major concerns in water reclamation and reuse at managed aquifer recharge (MAR) sites. In this study, the transport and fate of bacteriophages MS2, PRD1, and FX174 were studied in sediment and stormwater (SW) collected from a MAR site in Parafield, Australia. Column ex...

  18. The impact of green stormwater infrastructure installation on surrounding health and safety

    Science.gov (United States)

    Michelle C. Kondo; Sarah C. Low; Jason Henning; Charles C. Branas

    2015-01-01

    We investigated the health and safety effects of urban green stormwater infrastructure (GSI) installments. We conducted a difference-in-differences analysis of the effects of GSI installments on health (e.g., blood pressure, cholesterol and stress levels) and safety (e.g., felonies, nuisance and property crimes, narcotics crimes) outcomes from 2000 to 2012 in...

  19. Evaluating the Effect of Green Infrastructure Stormwater Best Management Practices on New England Stream Habitat

    Science.gov (United States)

    The U.S. EPA is evaluating the effectiveness of green infrastructure (GI) stormwater best management practices (BMPs) on stream habitat at the small watershed (< HUC12) scale in New England. Predictive models for thermal regime and substrate characteristics (substrate size, % em...

  20. Approach and case-study of green infrastructure screening analysis for urban stormwater control.

    Science.gov (United States)

    Eaton, Timothy T

    2018-03-01

    Urban stormwater control is an urgent concern in megacities where increased impervious surface has disrupted natural hydrology. Water managers are increasingly turning to more environmentally friendly ways of capturing stormwater, called Green Infrastructure (GI), to mitigate combined sewer overflow (CSO) that degrades local water quality. A rapid screening approach is described to evaluate how GI strategies can reduce the amount of stormwater runoff in a low-density residential watershed in New York City. Among multiple possible tools, the L-THIA LID online software package, using the SCS-CN method, was selected to estimate relative runoff reductions expected with different strategies in areas of different land uses in the watershed. Results are sensitive to the relative areas of different land uses, and show that bioretention and raingardens provide the maximum reduction (∼12%) in this largely residential watershed. Although commercial, industrial and high-density residential areas in the watershed are minor, larger runoff reductions from disconnection strategies and porous pavement in parking lots are also possible. Total stormwater reductions from various combinations of these strategies can reach 35-55% for individual land uses, and between 23% and 42% for the entire watershed. Copyright © 2017. Published by Elsevier Ltd.

  1. Urban Stormwater Runoff. Instructor Guide. Working for Clean Water: An Information Program for Advisory Groups.

    Science.gov (United States)

    Simko, Robert A.

    Urban stormwater runoff collects pollutants from many parts of a city and is an important consideration in water quality planning. Presented is an instructor's guide for a learning session covering various aspects of urban runoff including pollutant sources, management practices, and regulatory programs. Intended for citizen advisory groups, this…

  2. Towards effective monitoring of urban stormwater for better design and management

    Directory of Open Access Journals (Sweden)

    Bharat Maharjan

    2016-08-01

    Full Text Available The lack of information due to insufficient data availability and an improper sampling method for stormwater generates constraint and uncertainty in addressing all storm events. In such conditions, it is difficult to assess actual concentrations and mass loads. This results in a backlog in decision-making for sustainable planning, design and policy formulation, e.g. retrofitting alternatives to traditional systems for reducing runoff and pollutants. It is essential to set standardized sampling and analysis procedures in order to achieve reliable and representative data. They need to be optimal and effective due to the costs and difficulties in sampling and analysis. The study reviews the effectiveness of largely best practiced sampling procedures in research papers. Likely site selection approaches, monitoring parameters and sample collection systems are compiled with their effectiveness, affordability and applicability. An optimal stormwater sampling programme is deducted and recommended for Tallinn stormwater catchment area. Moreover, the study provides an opportunity to select the suitable monitoring programme from the effective options such that it can be utilized to obtain coherent stormwater data.

  3. Can stormwater control measures restore altered urban flow regimes at the catchment scale?

    Science.gov (United States)

    Li, Congying; Fletcher, Tim D.; Duncan, Hugh P.; Burns, Matthew J.

    2017-06-01

    Over the last 20-30 years, there has been an evolution in urban stormwater management towards the use of stormwater control measures (SCMs) at or near the source of the runoff. These approaches aim to protect or restore natural elements of the flow regime. However, evidence of the success of such approaches is to date limited. We reviewed attempts to both model and monitor the catchment-scale hydrological consequences of SCMs. While many catchment-scale studies on the hydrologic effects of SCMs are based on computer simulation, these modeling approaches are limited by many uncertainties. The few existing monitoring studies provide early indications of the potential of SCMs to deliver more natural flow regimes, but many questions remain. There is an urgent need for properly monitored studies that aim to assess the hydrologic effects of SCMs at the catchment scale. In future monitoring studies, these hydrologic effects need to be characterized using appropriate flow metrics at a range of scales (from site scale to catchment scale), and changes to flow metrics by SCMs need to be assessed using robust statistical methods. Such studies will give confidence to stormwater and river managers of the feasibility and benefits of "low impact" approaches to stormwater management.

  4. The impact of stormwater source-control strategies on the (low) flow regime of urban catchments.

    Science.gov (United States)

    Hamel, Perrine; Fletcher, Tim D

    2014-01-01

    Stormwater management strategies increasingly recognise the need to emulate the pre-development flow regime, in addition to reducing pollutant concentrations and loads. However, it is unclear whether current design approaches for stormwater source-control techniques are effective in restoring the whole flow regime, and in particular low flows, towards their pre-development levels. We therefore modelled and compared a range of source-control stormwater management strategies, including some specifically tailored towards enhancing baseflow processes. The strategies were assessed based on the total streamflow volume and three low flow metrics. Strategies based on harvesting tanks showed much greater volume reduction than those based on raingardens. Strategies based on a low flow rate release, aimed at mimicking natural baseflow, failed to completely restore the baseflow regime. We also found that the sensitivity of the low flow metrics to the proportion of catchment treated varied amongst metrics, illustrating the importance of metrics selection in the assessment of stormwater strategies. In practice, our results suggest that realistic scenarios using low flow release from source-control techniques may not be able to fully restore the low flow regime, at least for perennial streams. However, a combination of feasibly-sized tanks and raingardens is likely to restore the baseflow regime to a great extent, while also benefitting water quality through the retention and filtration processes.

  5. Monitoring nitrogen loading and retention in an urban stormwater detention pond.

    Science.gov (United States)

    Rosenzweig, Bernice R; Smith, James A; Baeck, Mary Lynn; Jaffé, Peter R

    2011-01-01

    Stormwater detention ponds have become ubiquitous in urbanized areas and have been suggested as potential hotspots of N transformation within urban watersheds. As a result, there is a great deal of interest in their use as structural best management practices to reduce the excessive N export from these watersheds. We conducted continuous monitoring of the influent and effluent N loads of a stormwater detention pond located on the Princeton University campus in Princeton, New Jersey. Our monitoring was conducted during four 21-d periods representing the four seasons of the northeastern United States. Water quality samples were collected and analyzed for nitrate (NO3-) during all four monitoring periods. During two of these periods, loads of ammonium (NH4+), dissolved organic N, and particulate N (PN) were measured. Our results show that NO3- dominated the influent N load, particularly in dry weather inflows to the detention pond. However, PN, which is often neglected in stormwater quality monitoring, made up as much as 30% of the total load and an even greater fraction during storm events. The results of our monitoring suggest that seasonal variation may play an important role in N retention within the detention pond. Although retention of NO3-, the most dominant fraction of N in the influent stormwater, was observed during the summer sampling period, no significant NO3- retention was observed during the spring or the two cold-weather sampling periods.

  6. Stormwater management criteria for on-site pollution control: a comparative assessment of international practices.

    Science.gov (United States)

    Sage, Jérémie; Berthier, Emmanuel; Gromaire, Marie-Christine

    2015-07-01

    Over the last decade, a growing interest has been shown toward innovative stormwater management practices, breaking away from conventional "end of pipe" approaches (based on conveying water offsite to centralized detention facilities). Innovative strategies, referred to as sustainable urban drainage systems, low impact development (LID) or green infrastructures, advocating for management of runoff as close to its origin as possible, have therefore gained a lot of popularity among practitioners and public authorities. However, while the need for pollution control is generally well accepted, there is no wide agreement about management criteria to be given to developers. This article hence aims to compare these criteria through literature analysis of different state or local stormwater management manuals or guidelines, investigating both their suitability for pollution control and their influence on best management practices selection and design. Four categories of criteria were identified: flow-rate limitations, "water quality volumes" (to be treated), volume reduction (through infiltration or evapotranspiration), and non-hydrologic criteria (such as loads reduction targets or maximum effluent concentrations). This study suggests that hydrologic criteria based on volume reduction (rather than treatment) might generally be preferable for on-site control of diffuse stormwater pollution. Nonetheless, determination of an appropriate management approach for a specific site is generally not straightforward and presents a variety of challenges for site designers seeking to satisfy local requirements in addressing stormwater quantity and quality issues. The adoption of efficient LID solution may therefore strongly depend on the guidance given to practitioners to account for these management criteria.

  7. 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.

  8. Phosphorus retention in stormwater control structures across streamflow in urban and suburban watersheds

    Science.gov (United States)

    Recent studies have shown that stormwater control measures (SCMs) are less effective at retaining phosphorus (P) than nitrogen. We compared P retention between two urban/suburban SCMs and their adjacent restored stream reaches at the Baltimore Long-Term Ecological Study (LTER) s...

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

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, Asbjørn Haaning; 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;...

  10. Evaluation of the effectiveness of an urban stormwater treatment unit in Madison, Wisconsin, 1996-97

    Science.gov (United States)

    Waschbusch, Robert J.

    1999-01-01

    An urban stormwater treatment unit was tested as part of an ongoing program of urban nonpoint- pollution research in Madison, Wis. Flow measurements were made and water samples were collected at the inlet to, outlet from, and bypass around the treatment chamber of the device that was installed to collect the runoff from a city maintenance yard.

  11. 77 FR 1687 - EPA Workshops on Achieving Water Quality Through Integrated Municipal Stormwater and Wastewater...

    Science.gov (United States)

    2012-01-11

    ... stormwater can present difficult and expensive engineering challenges. Population growth, aging... public health and water quality. The approach takes advantage of the flexibilities in existing EPA... infrastructure approaches and are starting to see that the value of such projects goes beyond protecting water...

  12. Introduction to EPA's Stormwater Calculator - Incorporating Low Impact Development and Climate Science Tools

    Science.gov (United States)

    The EPA Office of Research and Development released its National Stormwater Calculator (SWC) which is available at: http://www.epa.gov/nrmrl/wswrd/wq/models/swc/ (contact: SWC@EPA.gov). It is a desktop application that estimates the annual amount of rainwater and frequency of run...

  13. Elimination and accumulation of polycyclic aromatic hydrocarbons (PAHs) in urban stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Istenič, Daria; Arias, Carlos Alberto; Matamoros, Victor

    2011-01-01

    The concentrations of polycyclic aromatic hydrocarbons (PAHs) in water and sediments of seven wet detention ponds receiving urban stormwater were investigated. The ponds comprised traditional wet detention ponds with a permanent wet volume and a storage volume as well as ponds that were expanded...

  14. MULTIDISCIPLINARY MANAGEMENT OF STORMWATER RUNOFF - THE SHEPHERD CREEK WATERSHED PILOT STUDY

    Science.gov (United States)

    Increased stormwater runoff from urbanized areas is a primary degrading influence on environmental quality. In addition to ecological, hydrological, and consideration of soils and land cover, we find that economics and legal concepts play an important role in creating a sustainab...

  15. 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).

  16. STORMWATER TREATMENT AT CRITICAL AREAS: THE MULTI-CHAMBERED TREATMENT TRAIN (MCTT)

    Science.gov (United States)

    Past studies have identified urban runoff as a major contributor to the degradation of many urban streams and rivers. The objective of this research was to characterize typical toxicant concentrations in stormwater, and investigate the effectiveness of treatment processes to con...

  17. Multi-Chambered Treatment Train (MCTT) For Treating Stormwater Runoff From Highly Polluted Source Areas

    Science.gov (United States)

    A full-scaled Multi-Chambered Treatment Train (MCTT) stormwater treatment system was tested in Taiwan during the spring and summer of 2007. The MCTT was installed in a parking lot in Ping-Lin, Northern Taiwan. The site is 85% impervious and has a drainage area to the MCTT unit of...

  18. Sustainability assessment of stormwater management systems and the importance of pollutants in runoff

    DEFF Research Database (Denmark)

    Brudler, Sarah; Arnbjerg-Nielsen, Karsten; Ammitsøe, Christian

    substance groups present in runoff, metals cause the highest impacts. To integrate this method into holistic sustainability assessment, we assess the complete life cycle of a complex stormwater management. We show that runoff discharges have a high relative importance: The impacts exceed the combined...

  19. Effectiveness of catch basins equipped with hoods in retaining gross solids and hydrocarbons in highway runoff, Southeast Expressway, Boston, Massachusetts, 2008-09

    Science.gov (United States)

    Smith, Kirk P.

    2011-01-01

    Stormwater mobilizes litter and other debris along the roadway where it is transported to the highway drainage systems. Initial treatment for stormwater runoff typically is provided by catch basins in highway settings. Modification of catch basins to include hoods that cover the catch-basin outlet is intended to enhance catch-basin performance by retaining floatable debris and various hydrophobic organic compounds that tend to float on the water surface within the sump of the catch basin. The effectiveness of six deep-sump off-line catch basins equipped with hoods in reducing the mass of gross solids greater than 0.25 inches in diameter and concentrations of oil and grease (OG) and total petroleum hydrocarbons (TPH) was examined along the Southeast Expressway, in Boston, Massachusetts. Two deep-sump catch basins were equipped with cast-iron hoods. Three were equipped with molded plastic hoods, known as an Eliminator, and a single catch basin was equipped with a fiberglass anti-siphoning hood, known as a Snout. Samples of gross solids greater than 0.25 inches in diameter, excluding gravel and metallic materials, were routinely collected for a 6-month period from a collection structure mounted at the end of each catch-basin outlet pipe. After about 6 months, all floatable, saturated low-density and high-density solids were removed from each catch basin. In addition to the collection of samples of gross solids, samples of sump water from five catch basins and flow-weighted composite samples of stormwater from the outlet of one catch basin were collected and analyzed for concentrations of OG and TPH. A mass balance approach was used to assess the effectiveness of each catch basin equipped with a hood in retaining gross solids. The effectiveness of the deep-sump catch basins fitted with one of three types of hoods in retaining gross solids ranged from 27 to 52 percent. From 45 to 90 percent of the gross solids collected from the catch-basin sumps were composed of

  20. Integrating Hydrology, Ecology, and Biogeochemistry in Stormwater Management: the Vermont Experience

    Science.gov (United States)

    Bowden, W. B.

    2005-12-01

    Although Vermont has had a stormwater management program since the 1970's, support for the program languished during a period intense suburban development in several counties in the state, most notably Chittenden County next to Lake Champlain. Beginning in 2000, the state renewed efforts to address concerns that stormwater runoff from suburban developments had significantly degraded streams in the area and threatened the health of the Lake. The state employs an extensive, EPA-approved biomonitoring program (based on macroinvertebrates and fish) to assess the health of streams. However, it is difficult to translate these data into targets for stormwater management or to predict how and especially when they will change as a result of future management practices. The challenge of managing stormwater in this area is further compounded by a complete lack of historical hydrologic monitoring data. Ultimately a stakeholder-driven process developed that has lead to an innovative partnership among state agencies, resource managers, NGO's, the US-EPA and scientists. Through this partnership a unique consensus evolved that management for hydrologic targets by themselves would address most of the stakeholders' concerns. The new regulations that are emerging are based on two components. The first component relies on flow-duration curves (FDC's) derived from a simple, widely-used stormwater model (P-8) for which adequate input data are available. The model was calibrated for streams in other areas for which long-term hydrologic data were available and then used to generate `synthetic' FDC's for the stormwater impaired and a suite of `attainment' (developing, but currently un-impaired) watersheds in Vermont. Statistical (cluster) analyses of synthetic FDC's provide watershed-wide targets for hydrologic reduction. Sub-watershed mapping linked to further multivariate analysis of the flow data identify specific locations to implement best management practices (BMP's) that will

  1. Residual basins

    International Nuclear Information System (INIS)

    D'Elboux, C.V.; Paiva, I.B.

    1980-01-01

    Exploration for uranium carried out over a major portion of the Rio Grande do Sul Shield has revealed a number of small residual basins developed along glacially eroded channels of pre-Permian age. Mineralization of uranium occurs in two distinct sedimentary units. The lower unit consists of rhythmites overlain by a sequence of black shales, siltstones and coal seams, while the upper one is dominated by sandstones of probable fluvial origin. (Author) [pt

  2. Predicting Fecal Indicator Bacteria Fate and Removal in Urban Stormwater at the Watershed Scale

    Science.gov (United States)

    Wolfand, J.; Hogue, T. S.; Luthy, R. G.

    2016-12-01

    Urban stormwater is a major cause of water quality impairment, resulting in surface waters that fail to meet water quality standards and support their designated uses. Of the many stormwater pollutants, fecal indicator bacteria are particularly important to track because they are directly linked to pathogens which jeopardize public health; yet, their fate and transport in urban stormwater is poorly understood. Monitoring fecal bacteria in stormwater is possible, but due to the high variability of fecal indicators both spatially and temporally, single grab or composite samples do not fully capture fecal indicator loading. Models have been developed to predict fecal indicator bacteria at the watershed scale, but they are often limited to agricultural areas, or areas that receive frequent rainfall. Further, it is unclear whether best management practices (BMPs), such as bioretention or engineered wetlands, are able to reduce bacteria to meet water quality standards at watershed outlets. This research seeks to develop a model to predict fecal indicator bacteria in urban stormwater in a semi-arid climate at the watershed scale. Using the highly developed Ballona Creek watershed (89 mi2) located in Los Angeles County as a case study, several existing mechanistic models are coupled with a hydrologic model to predict fecal indicator concentrations (E. coli, enterococci, fecal coliform, and total coliform) at the outfall of Ballona Creek watershed, Santa Monica Bay. The hydrologic model was developed using InfoSWMM Sustain, calibrated for flow from WY 1998-2006 (NSE = 0.94; R2 = 0.95), and validated from WY 2007-2015 (NSE = 0.93; R2 = 0.95). The developed coupled model is being used to predict fecal indicator fate and transport and evaluate how BMPs can be optimized to reduce fecal indicator loading to surface waters and recreational beaches.

  3. Bioretention column study of bacteria community response to salt-enriched artificial stormwater.

    Science.gov (United States)

    Endreny, Theodore; Burke, David J; Burchhardt, Kathleen M; Fabian, Mark W; Kretzer, Annette M

    2012-01-01

    Cold climate cities with green infrastructure depend on soil bacteria to remove nutrients from road salt-enriched stormwater. Our research examined how bacterial communities in laboratory columns containing bioretention media responded to varying concentrations of salt exposure from artificial stormwater and the effect of bacteria and salt on column effluent concentrations. We used a factorial design with two bacteria treatments (sterile, nonsterile) and three salt concentrations (935, 315, and 80 ppm), including a deionized water control. Columns were repeatedly saturated with stormwater or deionized and then drained throughout 5 wk, with the last week of effluent analyzed for water chemistry. To examine bacterial communities, we extracted DNA from column bioretention media at time 0 and at week 5 and used molecular profiling techniques to examine bacterial community changes. We found that bacterial community taxa changed between time 0 and week 5 and that there was significant separation between taxa among salt treatments. Bacteria evenness was significantly affected by stormwater treatment, but there were no differences in bacterial richness or diversity. Soil bacteria and salt treatments had a significant effect on the effluent concentration of NO, PO, Cu, Pb, and Zn based on ANOVA tests. The presence of bacteria reduced effluent NO and Zn concentrations by as much as 150 and 25%, respectively, while having a mixed effect on effluent PO concentrations. Our results demonstrate how stormwater can affect bacterial communities and how the presence of soil bacteria improves pollutant removal by green infrastructure. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. Methodologies for pre-validation of biofilters and wetlands for stormwater treatment.

    Directory of Open Access Journals (Sweden)

    Kefeng Zhang

    Full Text Available Water Sensitive Urban Design (WSUD systems are frequently used as part of a stormwater harvesting treatment trains (e.g. biofilters (bio-retentions and rain-gardens and wetlands. However, validation frameworks for such systems do not exist, limiting their adoption for end-uses such as drinking water. The first stage in the validation framework is pre-validation, which prepares information for further validation monitoring.A pre-validation roadmap, consisting of five steps, is suggested in this paper. Detailed methods for investigating target micropollutants in stormwater, and determining challenge conditions for biofilters and wetlands, are provided.A literature review was undertaken to identify and quantify micropollutants in stormwater. MUSIC V5.1 was utilized to simulate the behaviour of the systems based on 30-year rainfall data in three distinct climate zones; outputs were evaluated to identify the threshold of operational variables, including length of dry periods (LDPs and volume of water treated per event.The paper highlights that a number of micropollutants were found in stormwater at levels above various worldwide drinking water guidelines (eight pesticides, benzene, benzo(apyrene, pentachlorophenol, di-(2-ethylhexyl-phthalate and a total of polychlorinated biphenyls. The 95th percentile LDPs was exponentially related to system design area while the 5th percentile length of dry periods remained within short durations (i.e. 2-8 hours. 95th percentile volume of water treated per event was exponentially related to system design area as a percentage of an impervious catchment area.The out-comings of this study show that pre-validation could be completed through a roadmap consisting of a series of steps; this will help in the validation of stormwater treatment systems.

  5. 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.

  6. Probabilistic Determination of Green Infrastructure Pollutant Removal Rates from the International Stormwater BMP Database

    Science.gov (United States)

    Gilliom, R.; Hogue, T. S.; McCray, J. E.

    2017-12-01

    There is a need for improved parameterization of stormwater best management practices (BMP) performance estimates to improve modeling of urban hydrology, planning and design of green infrastructure projects, and water quality crediting for stormwater management. Percent removal is commonly used to estimate BMP pollutant removal efficiency, but there is general agreement that this approach has significant uncertainties and is easily affected by site-specific factors. Additionally, some fraction of monitored BMPs have negative percent removal, so it is important to understand the probability that a BMP will provide the desired water quality function versus exacerbating water quality problems. The widely used k-C* equation has shown to provide a more adaptable and accurate method to model BMP contaminant attenuation, and previous work has begun to evaluate the strengths and weaknesses of the k-C* method. However, no systematic method exists for obtaining first-order removal rate constants needed to use the k-C* equation for stormwater BMPs; thus there is minimal application of the method. The current research analyzes existing water quality data in the International Stormwater BMP Database to provide screening-level parameterization of the k-C* equation for selected BMP types and analysis of factors that skew the distribution of efficiency estimates from the database. Results illustrate that while certain BMPs are more likely to provide desired contaminant removal than others, site- and design-specific factors strongly influence performance. For example, bioretention systems show both the highest and lowest removal rates of dissolved copper, total phosphorous, and total nitrogen. Exploration and discussion of this and other findings will inform the application of the probabilistic pollutant removal rate constants. Though data limitations exist, this research will facilitate improved accuracy of BMP modeling and ultimately aid decision-making for stormwater quality

  7. 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 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.

  8. Influence of spontaneous vegetation in stormwater infiltration system clogging.

    Science.gov (United States)

    Gonzalez-Merchan, Carolina; Barraud, Sylvie; Bedell, Jean-Philippe

    2014-04-01

    The paper presents the role of spontaneous vegetation on the hydraulic performance of an infiltration basin. The objective of the research was more particularly to study this role of different types of spontaneous vegetation found in situ in an infiltration basin near Lyon. The saturated hydraulic conductivity of three areas covered by Phalaris arundinacea, Polygonum mite, Rumex crispus and similar non-vegetated zones was compared. Eight field campaigns were carried out from July 2010 to May 2011 in order to compare the performance of each type of vegetation and its evolution over time. The results suggest a positive impact of vegetation on hydraulic performance in particular in summer during the growth of the plants. The hydraulic conductivity in this period was twice to four times higher than in bare areas or in vegetated zones during the plant rest periods. Some species were also found more appropriate to limit clogging (Phalaris arundinacea) likely due to its specific structure and growth process.

  9. Stormwater quality from extensive green roofs in a subtropical region

    Science.gov (United States)

    Onis Pessoa, Jonas; Allasia, Daniel; Tassi, Rutineia; Vaz Viega, Juliana; Fensterseifer, Paula

    2016-04-01

    . Thus, under the assessed conditions and time, the green roofs, in general, have not provided an improvement of water quality as indicated by some authors. However, it was found that some of the measured parameters showed a gradual improvement during the monitoring period. This suggests that the age of green roofs can affect efficiency in the qualitative control of water. In this regard, long-term research can contribute to a better understanding quality of stormwater runoff from green roofs, especially in regions such as Brazil, where the implementation of green roofs is incipient and in a phase of adaptation to the different environmental conditions of the country.

  10. Assessing Pediatric Nurses' Knowledge About Chemical Flame Retardants.

    Science.gov (United States)

    Distelhorst, Laura; Bieda, Amy; DiMarco, Marguerite; Tullai-McGuinness, Susan

    Chemical flame retardants are routinely applied to children's products and are harmful to their health. Pediatric nurses are in a key position to provide education to caregivers on methods to decrease their children's exposure to these harmful chemicals. However, a critical barrier is the absence of any program to educate nurses about chemical flame retardants. In order to overcome this barrier, we must first assess their knowledge. This article provides key highlights every pediatric nurse should know about chemical flame retardants and reports the results of a knowledge assessment study. The purpose of this study was to (1) assess pediatric nurses' knowledge of chemical flame retardants, (2) determine what topic areas of chemical flame retardants pediatric nurses lack knowledge in, and (3) determine the best method to educate nurses about chemical flame retardants. A single sample cross-sectional questionnaire design was used. A total sample of 417 advanced practice registered nurses and registered nurses completed an online survey about chemical flame retardants. Pediatric nurses' knowledge of chemical flame retardants was low (M=13.4 out of 51). Articles, webinars, and e-mails were the primary preferred methods for education on the subject identified as a result of the survey. Pediatric nurses have a large knowledge deficit related to chemical flame retardants. The data collected from this study will help structure future educational formats for pediatric nurses on chemical flame retardants to increase their knowledge. Copyright © 2016 Elsevier Inc. All rights reserved.

  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. Recycling of salt-contaminated stormwater runoff for brine production at Virginia Department of Transportation road-salt storage facilities.

    Science.gov (United States)

    2008-01-01

    A large part of the Virginia Department of Transportation's (VDOT's) maintenance effort comprises the implementation of its snow removal and ice control program. Earlier research confirmed that VDOT captures significant volumes of salt-laden stormwat...

  13. Evaluation of the Role of Public Outreach and Stakeholder Engagement in Stormwater Funding Decisions in New England

    Science.gov (United States)

    A detailed report examining the role of public outreach and stakeholder engagement in stormwater funding decisions based on the experiences of eleven small and medium-sized communities in New England.

  14. 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,...

  15. 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......Partitioning of fluoranthene in stormwater runoff and other urban discharges was measured by a new analytical method based on passive dosing. Samples were collected at the inlet (n = 11) and outlet (n = 8) from a stormwater retention pond in Albertslund (Denmark), and for comparison samples were...... also obtained at a municipal wastewater treatment plant, a power plant, a contaminated site and a waste deposit in Copenhagen (n = 1 at each site). The freely dissolved concentration of 14C-fluoranthene in the samples was controlled by equilibrium partitioning from a pre-loaded polymer and the total...

  16. Stormwater Runoff Characteristics and Effective Management of Nonpoint Source Pollutants from a Highland Agricultural Region in the Lake Soyang Watershed

    Directory of Open Access Journals (Sweden)

    Jae Heon Cho

    2017-10-01

    Full Text Available The dense highland field area in the upstream region of the Lake Soyang watershed is subject to excessive soil erosion during the wet season. In this study, stormwater runoff from the Lake Soyang watershed was monitored during four rainfall events at 10 locations throughout 2016. The maximum SS concentration at Naedongcheon, which is located in the upper part of the Soyang River, reached 4598 mg/L. The event mean concentration (EMC of SS loads in Naedongcheon ranged from 82.2 mg/L to 926.3 mg/L. We found that, although the first flush events were usually concentrated in highly paved urban areas, a first flush occurred in the agricultural area of the dense highland field region. The first flush phenomenon was identified by a dimensionless cumulative runoff mass and volume curve (M(V curve, and the intensity of the first flush was analyzed by the coefficient of the nonlinear regression model and the FF30 and FF25 values (the fraction of pollution load transported by the first 30% and 25% of runoff, respectively. Nonlinear regression models using the power function were applied to fit the M(V curve, the FF30 values were inversely proportional to the coefficient a of the regression model. A long-term seasonal trend decomposition for monthly turbidity and precipitation was performed for the Lake Soyang. Long-term turbidity trend was approximately coincident with the trend in long-term precipitation. In addition, the present status of the best management practices (BMPs in the upper part of the Soyang River basin was investigated, and a survey of the management and operation of the BMPs was conducted for selected farmers.

  17. Fire-retardant decorative inks for aircraft interiors

    Science.gov (United States)

    Kourtides, D. A.; Nir, Z.; Mikroyannidis, J. A.

    1985-01-01

    Commercial and experimental fire retardants were screened as potential fire retardants for acrylic printing inks used on aircraft interior sandwich panels. The fire retardants are selected according to their physical properties and their thermostabilities. A criterion for selecting a more stable fire retardant is established. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) are used to determine thermostabilities. Results show that the fire retardant formulations are more thermally stable than the acrylic ink control. It is determined that an ink formulation containing a brominated phenol and carboxy-terminated butadiene acrylonitrile which has been modified with a brominated polymeric additive (BPA), yields the highest limiting oxygen index (LOI) of all the compounds tested. All of the fire-retardant formulations have a higher oxygen index than the baseline acrylic ink.

  18. Mass spectrometric characterization of halogenated flame retardants.

    Science.gov (United States)

    Guo, Tan; LaBelle, Bruce; Petreas, Myrto; Park, June-Soo

    2013-07-15

    Concerns about the adverse health effects of ubiquitous flame retardants spurred our interest in the development of a sensitive and reliable analytical method for these toxic compounds in various sample matrices. This study focuses on the investigation of fragmentation pathways and the structures of target ions of thirteen new halogenated flame retardants. In this study, we use gas chromatography (GC)/high-resolution double-focusing sector mass spectrometry to characterize the fragmentation pathways of these new flame retardants. Along with the isotope patterns, accurate mass data were acquired to verify the molecular formula. The fragmentation pathways are classified based on the types of bond dissociations, e.g. σ-bond cleavage, α-bond cleavage and multiple-bond dissociations with a hydrogen shift. The α-bond dissociation occurs among 1,2-bis-(2,4,6-tribromophenoxy)ethane, allyl 2,4,6-tribromophenyl ether (ATE), 2,3-dibromopropyl 2,4,6-tribromophenyl ether (DPTE) and 2-bromoallyl 2,4,6-tribromophenyl ether (BATE). The peak clusters that dominated ATE, BATE and hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) spectra correspond to two fragments as proved by accurate mass data and isotope patterns. These two fragments are formed as the result of two competing fragmentation pathways of radical loss and hydrogen shift. Fragmentation pathways of the other compounds are complex, involving cleavage of multiple bonds and hydrogen shifts. The accurate-mass-based GC/MS method offers great selectivity and sensitivity for quantitative analysis of the persistent organic pollutants. Thus, elucidation of the structures of the fragments is of prime importance for building an accurate-mass-based isotopic method. In addition, this study is useful for GC/MS/MS method development because multiple reaction monitoring (MRM) transitions of precursor ions and product ions may be easily elucidated based on these fragmentation patterns. Copyright © 2013 John Wiley & Sons, Ltd.

  19. Nanotechnology finding its way into flame retardancy

    Energy Technology Data Exchange (ETDEWEB)

    Schartel, Bernhard, E-mail: bernhard.schartel@bam.de [BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany)

    2014-05-15

    Nanotechnology is one of the key technologies of the 21{sup st} century. The exploitation of 'new' effects that arise from materials structured on the nano-scale has also been proposed successfully for flame retardancy of polymers since the end of the 90s. Of all of the approaches these include, at this time the use of nanocomposites offers the best potential for industrial application, also some other ideas are sketched, such as using electrospun nanofibers mats or layer-by-layer deposits as protection coatings, as well as sub-micrometer multilayer coatings as effective IR-mirrors. The general phenomena, inducing a flow limit in the pyrolysing melt and changing the fire residue, are identified in nanocomposites. Key experiments are performed such as quasi online investigation of the protection layer formation to understand what is going on in detail. The flame retardancy mechanisms are discussed and their impact on fire behaviour quantified. With the latter, the presentation pushes forward the state of the art. For instance, the heat shielding is experimentally quantified for a layered silicate epoxy resin nanocomposite proving that it is the only import mechanism controlling the reduction in peak heat release rate in the investigated system for different irradiations. The flame retardancy performance is assessed comprehensively illuminating not only the strengths but also the weak points of the concepts. Guidelines for materials development are deduced and discussed. Apart from inorganic fillers (layered silicate, boehmite, etc.) not only carbon nanoobjects such as multiwall carbon nanotubes, multilayer graphene and graphene are investigated, but also nanoparticles that are more reactive and harbor the potential for more beneficial interactions with the polymer matrix.

  20. Our Sedation Experience on Mentally Retarded Patients

    Directory of Open Access Journals (Sweden)

    Metin Alkan

    2014-03-01

    Full Text Available Aim: The majority of dental treatments can be performed under local anesthesia. However, sedation or general anesthesia are often required for mentally retarded patients presenting a lack of cooperation. The aim of this study was to retrospectively evaluate the outcomes of mentally retarded patients treated under sedation. Material and Method: The records of the 214 mentally retarded patients that were treated under sedation between 2010-2012 were retrospectively evaluated. The retrospective data included demographic variables, duriation of anesthesia, anti-epileptic drugs used, level of sedation, anesthetic agents, the type of dental treatment and adverse events during and after sedation. Results: In this study the mean age of patients was 22,49±9,54. The female/male ratio was 109/105. The number of ASA I, II, III patients were 43, 157 and 14 respectively. 16.8% of the patiens (n=36 was on one anti-epileptic drug regimen, while 29.9% of the patiens (n=54 was on more than one anti-epileptic drug regimen. The sedation levels were determined as minimal sedation (6.5%, n=14, moderate sedation (35%, n=75 and deep sedation (58.4%, n=125 respectively. The midazolam-ketamine combination was the most preferred anesthetic regimen (41.1%, n=88. Single dental extraction was the most performed dental treatment (58.4%, n=125. Postoperative nausea and vomiting was encountered in 3.7% of patients (n=8. Respiratuar depression occurred in 2 patients. Two patients developed bronchospasm, while one patient developed postoperative agitation, deep bradycardia and allergic reaction respectively. Discussion: We are of the opinion that sedation can be performed safely by choosing the appropriate drug and method without depressing respiration and reflexes.

  1. 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

    % 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.......Stormwater treatment facilities (STFs) are becoming increasingly widespread but knowledge on their performance is limited. This is due to difficulties in obtaining representative samples during storm events and documenting removal of the broad range of contaminants found in stormwater runoff...

  2. New hybrid halogen-free flame retardants

    Science.gov (United States)

    Kijowska, Dorota; Jankowski, Piotr

    2014-05-01

    The main objective of this work were researches concerning the methods of the in-situ modification of silicate layer-tubular mineral (SL-TM) halloysite, using the salts of melamine, i.e. melamine cyanurate. The modified mineral was used as flame retardant to thermoplastic polymers. In the case of the application of halloysite modified by melamine cyanurate to polyamide 6 (PA6) the highest parameters of vertical and horizontal flammability were achieved. The mechanical properties of filled polyamide 6 have been improved.

  3. Investigation of pressure retarded osmosis power production

    Directory of Open Access Journals (Sweden)

    Taousanidis Nikolaos

    2017-01-01

    Full Text Available A major source of energy exists where there is mixing between aqueous solutions of different salinities. This energy source is particularly concentrated where fresh water rivers flow on to the ocean. The power, represented by the osmotic pressure difference between fresh water and salt water, may be called salinity gradient power. In this study the pressure retarded osmosis method for the extraction of salinity gradients’ energy is investigated, main problems and difficulties are pointed out and finally the whole subject is justified with experimental results.

  4. San Mateo Creek Basin

    Science.gov (United States)

    The San Mateo Creek Basin comprises approximately 321 square miles within the Rio San Jose drainage basin in McKinley and Cibola counties, New Mexico. This basin is located within the Grants Mining District (GMD).

  5. Assessment of macroinvertebrate communities in adjacent urban stream basins, Kansas City, Missouri, metropolitan area, 2007 through 2011

    Science.gov (United States)

    Christensen, Eric D.; Krempa, Heather M.

    2013-01-01

    Macroinvertebrates were collected as part of two separate urban water-quality studies from adjacent basins, the Blue River Basin (Kansas City, Missouri), the Little Blue River and Rock Creek Basins (Independence, Missouri), and their tributaries. Consistent collection and processing procedures between the studies allowed for statistical comparisons. Seven Blue River Basin sites, nine Little Blue River Basin sites, including Rock Creek, and two rural sites representative of Missouri ecological drainage units and the area’s ecoregions were used in the analysis. Different factors or levels of urban intensity may affect the basins and macroinvertebrate community metrics differently, even though both basins are substantially developed above their downstream streamgages (Blue River, 65 percent; Little Blue River, 52 percent). The Blue River has no flood control reservoirs and receives wastewater effluent and stormflow from a combined sewer system. The Little Blue River has flood control reservoirs, receives no wastewater effluent, and has a separate stormwater sewer system. Analysis of macroinvertebrate community structure with pollution-tolerance metrics and water-quality parameters indicated differences between the Blue River Basin and the Little Blue River Basin.

  6. Polysiloxane-Based Organoclay Nanocomposites as Flame Retardants

    Science.gov (United States)

    2013-01-01

    Polysiloxanes INTRODUCTION Halogen -based flame - retardant (FR) polymers and additives have been a cost-effective solution for FR appli- cations. However, there...D ec em be r 20 13 non- halogenated flame retardant polymers. Green Chem. 2011, 13 (3), 659–665. 7. Lewicki, J.P.; Liggat, J.J.; Patel, M. The...blended through several techniques with organoclays Cloisite 30B, 10A and Naþ ranging from 1 to 5 wt.%. Thermal and flame - retardant analysis

  7. Dysmorphology and mental retardation: molecular cytogenetic studies in dysmorphic mentally retarded patients.

    NARCIS (Netherlands)

    Buggenhout, G.J.C.M. van; Ravenswaaij-Arts, C.M.A. van; Mieloo, H.; Syrrou, M.; Hamel, B.C.J.; Brunner, H.G.; Fryns, J.P.

    2001-01-01

    In an institutionalised population of 471 mentally retarded adult residents (436 males and 35 females), 18 patients (16 males and 2 females) with dysmorphic features were selected to perform FISH studies by using subtelomeric probes to discover cryptic terminal deletions or duplications,

  8. Distal joint contractures, mental retardation, characteristic face and growth retardation: Chitayat syndrome revisited.

    NARCIS (Netherlands)

    Wortmann, S.B.; Rodenburg, R.J.T.; Schwahn, B.; Smeitink, J.A.M.; Morava, E.

    2007-01-01

    We report on a patient with congenital distal limb contractures, characteristic face, prominent metopic sutures, narrow forehead, severe psychomotor and growth retardation, white matter lesions and failure to thrive. The child has many overlapping features with those reported previously by Chitayat.

  9. Issues Affecting Community Attitudes and Intended Behaviours in Stormwater Reuse: A Case Study of Salisbury, South Australia

    Directory of Open Access Journals (Sweden)

    Zhifang Wu

    2012-10-01

    Full Text Available Stormwater has been recognised as one of the additional/alternative sources of water to augment freshwater supply and address the growing needs of humankind. South Australia has been a leader in the development of large-scale urban stormwater harvesting schemes in Australia for nearly 50 years and the Salisbury Local Government Area (LGA, in particular, is at the forefront of urban stormwater management and recycling, not only in the state of South Australia, but worldwide. This is mainly due to its pioneering achievements in stormwater capture and treatment through the managed aquifer recharge (MAR process. However, there are many challenges in implementing water reuse strategies and past studies have identified public health concerns and public acceptance as major challenges. In line with this, our team conducted an internet survey to gauge the attitude and intentions of Salisbury LGA residents to use stormwater treated through the MAR process for non-potable uses. We found that respondents’ emotions and perceptions of health risk, regarding the use of treated stormwater, were closely related to the proximity of the end use to human contact. In terms of quality indicators, colour, odour, and salt levels were all seen as being important. Quality preferences were also closely related to the proximity of the end use to human contact, and reflected the use of water for indoor/outdoor purposes.

  10. Adapting the social-ecological system framework for urban stormwater management: the case of green infrastructure adoption

    Directory of Open Access Journals (Sweden)

    Carli D. Flynn

    2016-12-01

    Full Text Available Stormwater management has long been a critical societal and environmental challenge for communities. An increasing number of municipalities are turning to novel approaches such as green infrastructure to develop more sustainable stormwater management systems. However, there is a need to better understand the technological decision-making processes that lead to specific outcomes within urban stormwater governance systems. We used the social-ecological system (SES framework to build a classification system for identifying significant variables that influence urban stormwater governance decisions related to green infrastructure adoption. To adapt the framework, we relied on findings from observations at national stormwater meetings in combination with a systematic literature review on influential factors related to green infrastructure adoption. We discuss our revisions to the framework that helped us understand the decision by municipal governments to adopt green infrastructure. Remaining research needs and challenges are discussed regarding the development of an urban stormwater SES framework as a classification tool for knowledge accumulation and synthesis.

  11. Rotatable broadband retarders for far infrared spectroscopic ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Kang, T.D.; Carr, G.; Zhou, T.; Kotelyanskii, M.; Sirenko, A.A.

    2010-12-09

    Rotatable retarders have been developed for applications in spectroscopic, full Mueller Matrix ellipsometry in the far-IR spectral range. Several materials, such as silicon, KRS-5, and a commercial polymer plastic (TOPAS) have been utilized to achieve a fully adjustable retardation between 0{sup o} and 90{sup o}. Experimental characteristics of the rotatable retarders that utilize three- and four-bounce designs are compared with calculations. We discuss the effect of light focusing on the performance of these rotatable retarders. Broadband optical retarders are required for spectroscopic ellipsometry in its full Mueller matrix (MM) realization. Performance of the MM ellipsometer depends on the capability to produce substantially linearly-independent Stokes vectors for the light incident onto the sample. As has been shown, the errors in the measuredMMof the sample are proportional to the condition number of the 4 x 4 matrix composed of the Stokes vectors of four polarization states incident at the sample. It can be proven that it is impossible to cover the Poincare sphere with linearly-independent Stokes vectors by only changing the linear polarization at the input surface of a stationary retarder. As we will illustrate further in this paper, total coverage of the Poincare sphere is possible by rotating a tandem of a linear polarizer and a retarder with a retardation of 90{sup o}. It is this goal that we are trying to achieve in the retarder designs described in this paper.

  12. Crack retardation by load reduction during fatigue crack propagation

    International Nuclear Information System (INIS)

    Kim, Hyun Soo; Nam, Ki Woo; Ahn, Seok Hwan; Do, Jae Yoon

    2003-01-01

    Fracture life and crack retardation behavior were examined experimentally using CT specimens of aluminum alloy 5083. Crack retardation life and fracture life were a wide difference between 0.8 and 0.6 in proportion to ratio of load reduction. The wheeler model retardation parameter was used successfully to predict crack growth behavior. By using a crack propagation rule, prediction of fracture life can be evaluated quantitatively. A statistical approach based on Weibull distribution was applied to the test data to evaluate the dispersion in the retardation life and fracture life by the change of load reduction

  13. 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

  14. Impacts of stormwater runoff in the Southern California Bight: Relationships among plume constituents

    Science.gov (United States)

    Reifel, K.M.; Johnson, S.C.; DiGiacomo, P.M.; Mengel, M.J.; Nezlin, N.P.; Warrick, J.A.; Jones, B.H.

    2009-01-01

    The effects from two winter rain storms on the coastal ocean of the Southern California Bight were examined as part of the Bight '03 program during February 2004 and February-March 2005. The impacts of stormwater from fecal indicator bacteria, water column toxicity, and nutrients were evaluated for five major river discharges: the Santa Clara River, Ballona Creek, the San Pedro Shelf (including the Los Angeles, San Gabriel, and Santa Ana Rivers), the San Diego River, and the Tijuana River. Exceedances of bacterial standards were observed in most of the systems. However, the areas of impact were generally spatially limited, and contaminant concentrations decreased below California Ocean Plan standards typically within 2-3 days. The largest bacterial concentrations occurred in the Tijuana River system where exceedances of fecal indicator bacteria were noted well away from the river mouth. Maximum nitrate concentrations (~40 ??M) occurred in the San Pedro Shelf region near the mouth of the Los Angeles River. Based on the results of general linear models, individual sources of stormwater differ in both nutrient concentrations and the concentration and composition of fecal indicator bacteria. While nutrients appeared to decrease in plume waters due to simple mixing and dilution, the concentration of fecal indicator bacteria in plumes depends on more than loading and dilution rates. The relationships between contaminants (nutrients and fecal indicator bacteria) and plume indicators (salinity and total suspended solids) were not strong indicating the presence of other potentially important sources and/or sinks of both nutrients and fecal indicator bacteria. California Ocean Plan standards were often exceeded in waters containing greater than 10% stormwater (coliforms and Enterococcus spp. and in the 28-30 salinity range (10-16% stormwater) for fecal coliforms. Nutrients showed a similar pattern with the highest median concentrations in water with greater than 10

  15. Hydrology of the Johnson Creek Basin, Oregon

    Science.gov (United States)

    Lee, Karl K.; Snyder, Daniel T.

    2009-01-01

    and winter precipitation totals were used to anticipate flooding of Holgate Lake. Several factors affect annual mean flow of Johnson Creek. More precipitation falls in the southeastern area of the basin because of the topographic setting. Runoff from much of the northern and western areas of the basin does not flow into Johnson Creek due to permeable deposits, interception by combined sewer systems, and by groundwater flow away from Johnson Creek. Inflow from Crystal Springs Creek accounts for one-half of the increase in streamflow of Johnson Creek between the Sycamore and Milwaukie sites. Low flows of Johnson Creek vary as a result of fluctuations in groundwater discharge to the creek, although past water uses may have decreased flows. The groundwater contributions to streamflow upstream of river mile (RM) 5.5 are small compared to contributions downstream of this point. Comparison of flows to a nearby basin indicates that diversions of surface water may have resulted in a 50 percent decrease in low flows from about 1955 to 1977. Runoff from the drainage basin area upstream of the Johnson Creek at Sycamore site contributes more to peak streamflow and peak volume than the drainage basin area between the Sycamore and Milwaukie sites. The average increase in annual peak streamflow and annual peak volume between the two sites was 11 and 24 percent, respectively. Decreased contribution in the lower area of the drainage basin is a result of infiltration, interception by drywell and combined sewer systems, and temporary overbank storage. Trends in flow typically associated with increasing urban development were absent in Johnson Creek. Annual, low, and high flows showed no trend from 1941 to 2006. Much of the infrastructure that may affect runoff from agricultural, residential, and urban development was in place prior to collection of hydrologic data in the basin. Management of stormwater in the urban areas by routing runoff from impervious surfaces to dry

  16. An Evaluation of Current Stormwater Best Management Practice Relationships Between Design and Efficiency: A Series of Local and National Case Studies

    OpenAIRE

    Goodwin, Amanda Ann

    2013-01-01

    Water quality continues to be threatened by human development activities such as stormwater runoff from urbanization. This study addresses the question of how stormwater Best Management Practice (BMP) system design choices affect pollutant removal efficiency, through the examination of 12 case study sites (across five states) that use three common BMP system design types (detention, retention, and wetland channel). Water quality information was obtained from the International Stormwater Datab...

  17. 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

  18. Social support of mentally retarded persons

    Directory of Open Access Journals (Sweden)

    Danuta Zwolinska

    2015-01-01

    Full Text Available Purpose: The aim of this work is to assess the relationship between the environment and mentally retarded persons. Material and methods: Information referring to social support of mentally retarded persons is a source material collected on the base of the data included in the Polish and foreign literature. The issues under discussion related to the following problems: social integration of persons with intellectual disabilities in a family and local environment, social functioning of people with mild intellectual disability, social rehabilitation of people with moderate, severe and profound intellectual disability and specific contact with people with disabilities. Results: For a person with an intellectual disability, the family is the source of acquisition of basic social skills that give him the opportunity for further development and performing certain social roles in a sense of safety. Full acceptance of the intellectually disabled, may dismiss their sense of shame and fear, and instill the satisfaction of belonging to a social community. Conclusions: Full social acceptance of people with intellectual disabilities is the basis for their assimilation and social functioning.

  19. Symmetries of Trautman retarded radial coordinates

    Science.gov (United States)

    Kolanowski, Maciej; Lewandowski, Jerzy

    2018-02-01

    We consider spacetime described by an observer that uses a Trautman retarded radial coordinate system. Given a metric tensor, we find all the local symmetries of the coordinates. They set a 10D family that can be parametrized by Poincaré algebra. This result is similar to the symmetries of an observer using the Gaussian normal spacetime radial coordinates and experiencing algebra deformation induced by the spacetime Riemann tensor. A new, surprising property of the retarded coordinates is a generic lack of smoothness in the symmetries. We show that, in general, the symmetries are not twice differentiable. In other words, a family of smooth symmetries is smaller than in the Gaussian normal spacetime coordinate case. We demonstrate examples of that non-smoothness and find the necessary conditions for the differentiability to the second order. We also discuss the consequences and relevance of that result for the geometric relational observables program. One can interpret our result by the fact that Trautman coordinates provide gauge conditions stronger than the Gaussian spacetime radial gauge.

  20. Mental Retardation. Fact Sheet = El Retraso Mental. Hojas Informativas Sobre Discapacidades.

    Science.gov (United States)

    National Information Center for Children and Youth with Disabilities, Washington, DC.

    This fact sheet on mental retardation is written in both English and Spanish. It begins with a vignette of a 15-year-old boy with mental retardation. Mental retardation is briefly explained as are some causes of mental retardation. It notes that a diagnosis of mental retardation looks at two things: first, the ability of a person's brain to learn,…

  1. Contribution of atmospheric dry deposition to stormwater loads for PAHs and trace metals in a small and highly trafficked urban road catchment.

    Science.gov (United States)

    Al Ali, Saja; Debade, Xavier; Chebbo, Ghassan; Béchet, Béatrice; Bonhomme, Céline

    2017-12-01

    A deep understanding of pollutant buildup and wash-off is essential for accurate urban stormwater quality modeling and for the development of stormwater management practices, knowing the potential adverse impacts of runoff pollution on receiving waters. In the context of quantifying the contribution of airborne pollutants to the contamination of stormwater runoff and assessing the need of developing an integrated AIR-WATER modeling chain, loads of polycyclic aromatic hydrocarbons (PAHs) and metal trace elements (MTEs) are calculated in atmospheric dry deposits, stormwater runoff, and surface dust stock within a small yet highly trafficked urban road catchment (~ 30,000 vehicles per day) near Paris. Despite the important traffic load and according to the current definition of "atmospheric" source, atmospheric deposition did not account for more than 10% of the PAHs and trace metal loads in stormwater samples for the majority of the events, based on the ratio of deposition to stormwater. This result shows that atmospheric deposition is not a major source of pollutants in stormwater, and thus, linking the air and water compartment in a modeling chain to have more accurate estimates of pollutant loads in stormwater runoff might not be relevant. Comparison of road dust with water samples demonstrates that only the fine fraction of the available stock is eroded during a rainfall event. Even if the atmosphere mostly generates fine particles, the existence of other sources of fine particles to stormwater runoff is highlighted.

  2. Effects of distributed and centralized stormwater best management practices and land cover on urban stream hydrology at the catchment scale

    Science.gov (United States)

    Loperfido, J. V.; Noe, Gregory B.; Jarnagin, S. Taylor; Hogan, Dianna M.

    2014-11-01

    Urban stormwater runoff remains an important issue that causes local and regional-scale water quantity and quality issues. Stormwater best management practices (BMPs) have been widely used to mitigate runoff issues, traditionally in a centralized manner; however, problems associated with urban hydrology have remained. An emerging trend is implementation of BMPs in a distributed manner (multi-BMP treatment trains located on the landscape and integrated with urban design), but little catchment-scale performance of these systems have been reported to date. Here, stream hydrologic data (March, 2011-September, 2012) are evaluated in four catchments located in the Chesapeake Bay watershed: one utilizing distributed stormwater BMPs, two utilizing centralized stormwater BMPs, and a forested catchment serving as a reference. Among urban catchments with similar land cover, geology and BMP design standards (i.e. 100-year event), but contrasting placement of stormwater BMPs, distributed BMPs resulted in: significantly greater estimated baseflow, a higher minimum precipitation threshold for stream response and maximum discharge increases, better maximum discharge control for small precipitation events, and reduced runoff volume during an extreme (1000-year) precipitation event compared to centralized BMPs. For all catchments, greater forest land cover and less impervious cover appeared to be more important drivers than stormwater BMP spatial pattern, and caused lower total, stormflow, and baseflow runoff volume; lower maximum discharge during typical precipitation events; and lower runoff volume during an extreme precipitation event. Analysis of hydrologic field data in this study suggests that both the spatial distribution of stormwater BMPs and land cover are important for management of urban stormwater runoff. In particular, catchment-wide application of distributed BMPs improved stream hydrology compared to centralized BMPs, but not enough to fully replicate forested

  3. Effects of distributed and centralized stormwater best management practices and land cover on urban stream hydrology at the catchment scale

    Science.gov (United States)

    Loperfido, John V.; Noe, Gregory B.; Jarnagin, S. Taylor; Hogan, Dianna M.

    2014-01-01

    Urban stormwater runoff remains an important issue that causes local and regional-scale water quantity and quality issues. Stormwater best management practices (BMPs) have been widely used to mitigate runoff issues, traditionally in a centralized manner; however, problems associated with urban hydrology have remained. An emerging trend is implementation of BMPs in a distributed manner (multi-BMP treatment trains located on the landscape and integrated with urban design), but little catchment-scale performance of these systems have been reported to date. Here, stream hydrologic data (March, 2011–September, 2012) are evaluated in four catchments located in the Chesapeake Bay watershed: one utilizing distributed stormwater BMPs, two utilizing centralized stormwater BMPs, and a forested catchment serving as a reference. Among urban catchments with similar land cover, geology and BMP design standards (i.e. 100-year event), but contrasting placement of stormwater BMPs, distributed BMPs resulted in: significantly greater estimated baseflow, a higher minimum precipitation threshold for stream response and maximum discharge increases, better maximum discharge control for small precipitation events, and reduced runoff volume during an extreme (1000-year) precipitation event compared to centralized BMPs. For all catchments, greater forest land cover and less impervious cover appeared to be more important drivers than stormwater BMP spatial pattern, and caused lower total, stormflow, and baseflow runoff volume; lower maximum discharge during typical precipitation events; and lower runoff volume during an extreme precipitation event. Analysis of hydrologic field data in this study suggests that both the spatial distribution of stormwater BMPs and land cover are important for management of urban stormwater runoff. In particular, catchment-wide application of distributed BMPs improved stream hydrology compared to centralized BMPs, but not enough to fully replicate forested

  4. A methodology for ranking and hazard identification of xenobiotic organic compounds in urban stormwater

    DEFF Research Database (Denmark)

    Baun, Anders; Eriksson, Eva; Ledin, Anna

    2006-01-01

    that sort out problematic and hazardous compounds based on inherent physico-chemical and biological properties. The outcomes of the RICH procedure are separate lists for both water phase and solid phase associated compounds. These lists comprise: a justified list of compounds which can be disregarded...... in hazard/risk assessments, a justified list of stormwater priority pollutants which must be included in hazard/risk assessments, and a list of compounds which may be present in discharged stormwater, but cannot be evaluated due to lack of data. The procedure was applied to 233 xenobiotic organic chemicals...... and the focus on the phases relevant for monitoring or risk assessment in the aquatic environment refines the list of “compounds of concern” when compared to the outcome of existing classification schemes. In this paper the RICH procedure is focused on effects in the aquatic environment exemplified...

  5. Risk management, financial evaluation and funding for wastewater and stormwater reuse projects.

    Science.gov (United States)

    Furlong, Casey; De Silva, Saman; Gan, Kein; Guthrie, Lachlan; Considine, Robert

    2017-04-15

    This paper has considered risk management, financial evaluation and funding in seven Australian wastewater and stormwater reuse projects. From the investigated case studies it can be seen that responsible parties have generally been well equipped to identify potential risks. In relation to financial evaluation methods some serious discrepancies, such as time periods for analysis, and how stormwater benefits are valued, have been identified. Most of the projects have required external, often National Government, funding to proceed. As National funding is likely to become less common in the future, future reuse projects may need to be funded internally by the water industry. In order to enable this the authors propose that the industry requires (1) a standard project evaluation process, and (2) an infrastructure funders' forum (or committee) with representation from both utilities and regulators, in order to compare and prioritise future reuse projects against each other. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Risk assessment of Xenobiotics in stormwater discharged to Harrestrup Å, Denmark

    DEFF Research Database (Denmark)

    Eriksson, Eva; Baun, Anders; Mikkelsen, Peter Steen

    2007-01-01

    Surface waters are highly manipulated in many cities in Europe, and the flow is largely impacted by discharges of stormwater and combined sewer overflow. Toxicity tests shown adverse effects in some of these recipients due to the presence of xenobiotic organic carbons (XOCs). Harrestrup Å, situated...... in the City of Copenhagen, is one of these recipients, where biotest using algae showed measurable toxicity in eight samples taken in 2003. Twenty-five different XOCs were quantified in the same samples. The present study aimed at identifying the most relevant XOCs out of these 25 to be selected for further......-related pollutants. This clearly illustrates that there is a need for monitoring the stormwater quality in order to protect the ecosystems. It also shows that actions are needed to implement source control options and emission barriers. Twelve XOCs were selected for further evaluation of possible source control...

  7. Evaluation of Nonpoint Source Pollution in Stormwater Run-Off in Neighborhoods in San Francisco, California

    Science.gov (United States)

    Bailey, C.; Bailey, E.; Cai, W.; Chen, K.; Duario, D.; Gonzalez, S.; Li, A.; Liu, L. W.; Matic, M.; Wu, M. L.; Wu, X. P.; Xie, J.; Yue, J.; Yuen, K.; Kirwin, J. P.; Neiss, J.

    2007-12-01

    This is the San Francisco Bay watershed encompasses 40% of California. When precipitation occurs, nonpoint source pollutants such as fertilizers, heavy metals, pesticides, gas and oil, enter the San Francisco Bay through this watershed. These pollutants contain dangerous chemicals that can potentially impact people and local ecology. The goal of Project Watershed is for high school students to design a study that investigates nonpoint source pollution in their own neighborhood and correlate these findings to the human activity in the neighborhood. Fifteen high school students participating in this study designed a stormwater collection devise that was installed in the public storm drain near each students home. Stormwater samples where collected from each device during the period of December 2006 to April 2007. Students assessed the samples for nitrates, heavy metals, oil and grease, total petroleum hydrocarbons, toluene and methyl tert-butyl ether (MTBE). This study outlines the methods students used to design the study and a summary of results found.

  8. Assessing Non-Technical Site Suitability Criteria for Stormwater Capture, Treatment and Recharge

    Science.gov (United States)

    Eisenstein, W.

    2016-12-01

    This presentation will describe a new method for assessing non-technical site suitability criteria for the siting of stormwater capture, treatment and recharge (or stormwater CTR) facilities in Sonoma County, California, USA. "Non-technical site suitability criteria" include issues such as community acceptance, aesthetics, nuisances and hazards, and compatibility with neighboring land uses, and are distinguished from "technical criteria" such as hydrology and soil characteristics that are the traditional subject of suitability analyses. Non-technical criteria are rarely, if ever, considered in formal siting suitability studies conducted by agencies and municipalities, yet can be fatal to the prospects of a given project's construction if not identified and mitigated. The researchers developed a new method for identifying and spatially characterizing relevant non-technical criteria through interviews and questionnaires with community stakeholders, and introducing those criteria into a spatial multi-criteria decision analysis framework that assesses site suitabilty across a study watershed (the Upper Petaluma River watershed in Sonoma County).

  9. Seasonal Trends in Bioaccumulation of Heavy Metals in Fauna of Stormwater Ponds

    DEFF Research Database (Denmark)

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

    2013-01-01

    Fauna caught in three stormwater ponds, two receiving highway run-off and one receiving runoff from a center for trucks, was analyzed for copper, iron, zinc, cadmium, chromium, and lead. The fauna was monitored from March to October with 1-month intervals to evaluate seasonal trends...... in bioaccumulation. The results were compared with similar results from two natural shallow lakes of the same region. The study showed that there was some tendency for copper and also to some degree for other metals to be present in slightly higher concentrations in fauna of the ponds. There was, however, no clear...... seasonal trend in concentrations when looking at individual species or groups of species. The number of species caught in ponds and lakes was more or less identical, which together with an only slightly elevated heavy metal content of the fauna supported that stormwater ponds can contribute positively...

  10. Sustainable Approaches for Stormwater Quality Improvements with Experimental Geothermal Paving Systems

    Directory of Open Access Journals (Sweden)

    Kiran Tota-Maharaj

    2015-01-01

    Full Text Available This research assesses the next generation of permeable pavement systems (PPS incorporating ground source heat pumps (geothermal paving systems. Twelve experimental pilot-scaled pavement systems were assessed for its stormwater treatability in Edinburgh, UK. The relatively high variability of temperatures during the heating and cooling cycle of a ground source heat pump system embedded into the pavement structure did not allow the ecological risk of pathogenic microbial expansion and survival. Carbon dioxide monitoring indicated relatively high microbial activity on a geotextile layer and within the pavement structure. Anaerobic degradation processes were concentrated around the geotextile zone, where carbon dioxide concentrations reached up to 2000 ppm. The overall water treatment potential was high with up to 99% biochemical oxygen demand removal. The pervious pavement systems reduced the ecological risk of stormwater discharges and provided a low risk of pathogen growth.

  11. Can urban tree roots improve infiltration through compacted subsoils for stormwater management?

    Science.gov (United States)

    Bartens, Julia; Day, Susan D; Harris, J Roger; Dove, Joseph E; Wynn, Theresa M

    2008-01-01

    Global land use patterns and increasing pressures on water resources demand creative urban stormwater management. Strategies encouraging infiltration can enhance groundwater recharge and water quality. Urban subsoils are often relatively impermeable, and the construction of many stormwater detention best management practices (D-BMPs) exacerbates this condition. Root paths can act as conduits for water, but this function has not been demonstrated for stormwater BMPs where standing water and dense subsoils create a unique environment. We examined whether tree roots can penetrate compacted subsoils and increase infiltration rates in the context of a novel infiltration BMP (I-BMP). Black oak (Quercus velutina Lam.) and red maple (Acer rubrum L.) trees, and an unplanted control, were installed in cylindrical planting sleeves surrounded by clay loam soil at two compaction levels (bulk density = 1.3 or 1.6 g cm(-3)) in irrigated containers. Roots of both species penetrated the more compacted soil, increasing infiltration rates by an average of 153%. Similarly, green ash (Fraxinus pennsylvanica Marsh.) trees were grown in CUSoil (Amereq Corp., New York) separated from compacted clay loam subsoil (1.6 g cm(-3)) by a geotextile. A drain hole at mid depth in the CUSoil layer mimicked the overflow drain in a stormwater I-BMP thus allowing water to pool above the subsoil. Roots penetrated the geotextile and subsoil and increased average infiltration rate 27-fold compared to unplanted controls. Although high water tables may limit tree rooting depth, some species may be effective tools for increasing water infiltration and enhancing groundwater recharge in this and other I-BMPs (e.g., raingardens and bioswales).

  12. 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. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  13. Predicting Bacteria Removal by Enhanced Stormwater Control Measures (SCMs) at the Watershed Scale

    Science.gov (United States)

    Wolfand, J.; Bell, C. D.; Boehm, A. B.; Hogue, T. S.; Luthy, R. G.

    2017-12-01

    Urban stormwater is a major cause of water quality impairment, resulting in surface waters that fail to meet water quality standards and support their designated uses. Fecal indicator bacteria are present in high concentrations in stormwater and are strictly regulated in receiving waters; yet, their fate and transport in urban stormwater is poorly understood. Stormwater control measures (SCMs) are often used to treat, infiltrate, and release urban runoff, but field measurements show that the removal of bacteria by these structural solutions is limited (median log removal = 0.24, n = 370). Researchers have therefore looked to improve bacterial removal by enhancing SCMs through alterations in flow regimes or adding geomedia such as biochar. The present research seeks to develop a model to predict removal of fecal indicator bacteria by enhanced SCMs at the watershed scale in a semi-arid climate. Using the highly developed Ballona Creek watershed (290 km2) located in Los Angeles County as a case study, a hydrologic model is coupled with a stochastic water quality model to predict E. coli concentration near the outfall of the Ballona Creek, Santa Monica Bay. A hydrologic model was developed using EPA SWMM, calibrated for flow from water year 1998-2006 (NSE = 0.94; R2 = 0.94), and validated from water year 2007-2015 (NSE = 0.90; R2 = 0.93). This bacterial loading model was then linked to EPA SUSTAIN and a SCM bacterial removal script to simulate log removal of bacteria by various SCMs and predict bacterial concentrations in Ballona Creek. Preliminary results suggest small enhancements to SCMs that improve bacterial removal (<0.5 log removal) may offer large benefits to surface water quality and enable communities such as Los Angeles to meet their regulatory requirements.

  14. Engineering hyporheic zones for the attenuation of urban pesticides and other stormwater trace organic contaminants

    Science.gov (United States)

    Portmann, A. C.; Halpin, B. N.; Herzog, S.; Higgins, C.; McCray, J. E.

    2017-12-01

    The hyporheic zone (HZ) is a natural bioreactor that can provide in-stream attenuation of various nonpoint source contaminants. Main contributions of nonpoint source pollution are coming from urban stormwater and agricultural runoff, which both adversely impact aquatic life. Stormwater pollutants of concern commonly include nutrients, metals, pathogens, and trace organic contaminants (TOrCs). Despite substantial water quality challenges, current stormwater management typically focuses on water quantity issues rather than pollutant removal. Furthermore, current HZ restoration best management practices do not explicitly control HZ residence times, and generally only induce localized effects. To increase hyporheic exchange and therefore improving water quality, we introduced engineered streambeds featuring modifications to subsurface hydraulic conductivity (K) and reactivity - termed Biohydrochemical Enhancements for Streamwater Treatment (BEST). BEST modifications comprise subsurface modules that employ 1) low-permeability sediments to drive hyporheic exchange and control subsurface residence times, and 2) permeable reactive geomedia to change reaction rates within the HZ. Here we present performance data collected in constructed stream experiments, comparing an all-sand control condition with a stream containing BEST modules and a mixture of 70/30 sand/woodchips (v/v). We evaluated the attenuation of a suite of TOrCs in the BEST versus the control system for two different streambed media: a coarse sand with K = 0.48 cm/s and a fine sand with K = 0.16 cm/s. The range of TOrCs investigated comprises urban pesticides and other stormwater relevant TOrCs. Benefits of applying BEST include increased exchange between streamwater and HZ water, leading to diverse redox conditions that are beneficial for aquatic organisms and will facilitate in-stream pollutant transformation. Future work will focus on tailoring the BEST design for specific pollutants, thereby controlling HZ

  15. Long-term stormwater quantity and quality analysis using continuous measurements in a French urban catchment.

    Science.gov (United States)

    Sun, Siao; Barraud, Sylvie; Castebrunet, Hélène; Aubin, Jean-Baptiste; Marmonier, Pierre

    2015-11-15

    The assessment of urban stormwater quantity and quality is important for evaluating and controlling the impact of the stormwater to natural water and environment. This study mainly addresses long-term evolution of stormwater quantity and quality in a French urban catchment using continuous measured data from 2004 to 2011. Storm event-based data series are obtained (716 rainfall events and 521 runoff events are available) from measured continuous time series. The Mann-Kendall test is applied to these event-based data series for trend detection. A lack of trend is found in rainfall and an increasing trend in runoff is detected. As a result, an increasing trend is present in the runoff coefficient, likely due to growing imperviousness of the catchment caused by urbanization. The event mean concentration of the total suspended solid (TSS) in stormwater does not present a trend, whereas the event load of TSS has an increasing tendency, which is attributed to the increasing event runoff volume. Uncertainty analysis suggests that the major uncertainty in trend detection results lies in uncertainty due to available data. A lack of events due to missing data leads to dramatically increased uncertainty in trend detection results. In contrast, measurement uncertainty in time series data plays a trivial role. The intra-event distribution of TSS is studied based on both M(V) curves and pollutant concentrations of absolute runoff volumes. The trend detection test reveals no significant change in intra-event distributions of TSS in the studied catchment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Further insight into the mechanism of heavy metals partitioning in stormwater runoff.

    Science.gov (United States)

    Djukić, Aleksandar; Lekić, Branislava; Rajaković-Ognjanović, Vladana; Veljović, Djordje; Vulić, Tatjana; Djolić, Maja; Naunovic, Zorana; Despotović, Jovan; Prodanović, Dušan

    2016-03-01

    Various particles and materials, including pollutants, deposited on urban surfaces are washed off by stormwater runoff during rain events. The interactions between the solid and dissolved compounds in stormwater runoff are phenomena of importance for the selection and improvement of optimal stormwater management practices aimed at minimizing pollutant input to receiving waters. The objective of this research was to further investigate the mechanisms responsible for the partitioning of heavy metals (HM) between the solid and liquid phases in urban stormwater runoff. The research involved the collection of samples from urban asphalt surfaces, chemical characterization of the bulk liquid samples, solids separation, particle size distribution fractionation and chemical and physico-chemical characterization of the solid phase particles. The results revealed that a negligible fraction of HM was present in the liquid phase (less than 3% by weight), while there was a strong correlation between the total content of heavy metals and total suspended solids. Examinations of surface morphology and mineralogy revealed that the solid phase particles consist predominantly of natural macroporous materials: alpha quartz (80%), magnetite (11.4%) and silicon diphosphate (8.9%). These materials have a low surface area and do not have significant adsorptive capacity. These materials have a low surface area and do not have significant adsorptive capacity. The presence of HM on the surface of solid particles was not confirmed by scanning electron microscopy and energy dispersive X-ray microanalyses. These findings, along with the results of the liquid phase sample characterization, indicate that the partitioning of HM between the liquid and solid phases in the analyzed samples may be attributed to precipitation processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Ehsan Ghane

    Full Text Available 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.

  18. Fundamental concepts and research priorities for advancing the science of urban stormwater hydrology and flood management

    Science.gov (United States)

    Nytch, C. J.; Meléndez-Ackerman, E. J.; Vivoni, E. R.; Grove, J. M.; Ortiz, J.

    2016-12-01

    In cities, hydrologic processes are drastically altered by human interventions. Modification of land cover and the enhancement of hydraulic efficiency have been documented as root causes of augmented stormwater runoff in urban watersheds, contributing to higher magnitude discharge events that pose flood risks for human communities. Climate change is expected to accelerate the hydrologic cycle, leading to more extreme events and increased flood risk. We present a synthesis of the physical and conceptual components and processes that govern urban stormwater runoff, and highlight key areas for future research. There is limited understanding about the fine-scale spatio-temporal relationships between gray, green, brown, and blue land cover features, the underlying social-ecological mechanisms responsible for their distribution, and the resulting effects on runoff dynamics. Horizontal and vertical complexity of urban morphological features and connectivity with the network of stormwater management infrastructure leads to heterogeneous and non-linear runoff responses that confound efforts for accurately predicting flood hazards. Quantitative analysis is needed to understand how urban drainage network structure varies across stream orders, and illuminate the landscape-scale patterns that potentially serve as organizing principles for generating hydrologic processes across diverse socio-bio-climatic domains and scales. Field-based and modeling studies are also needed to quantify the individual hydrologic capacities of urban structural elements and their cumulative effects at the watershed scale, particularly in developing regions. Integrated, transdisciplinary, multi-scalar approaches to framing and investigating complex socio-eco-techno-hydrologic systems are essential for advancing the science of urban stormwater hydrology, and developing resilient, multifunctional management solutions appropriate to the challenges of urban flooding in the twenty-first century.

  19. 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.

  20. Urban stormwater – greywater management system for sustainable urban water management at sub-watershed level

    Directory of Open Access Journals (Sweden)

    Arora Amarpreet Singh

    2017-01-01

    Full Text Available Urban water management involves urban water supply (import, treatment and distribution of water, urban wastewater management (collection, treatment and disposal of urban sewage and urban storm water management. Declining groundwater tables, polluted and declining sources of water, water scarcity in urban areas, unsatisfactory urban water supply and sanitation situation, pollution of receiving water bodies (including the ground water, and urban floods have become the concerns and issues of sustainable urban water management. This paper proposes a model for urban stormwater and sewage management which addresses these concerns and issues of sustainable urban water management. This model proposes segregation of the sewage into black water and greywater, and urban sub-watershed level stormwater-greywater management systems. During dry weather this system will be handling only the greywater and making the latter available as reclaimed water for reuse in place of the fresh water supply. During wet weather, the system will be taking care of (collection and treatment both the storm water and the greywater, and the excess of the treated water will be disposed off through groundwater recharging. Application of this model in the Patiala city, Punjab, INDIA for selected urban sub-watersheds has been tried. Information and background data required for the conceptualization and design of the sub-watershed level urban stormwater-greywater management system was collected and the system has been designed for one of the sub-watersheds in the Patiala city. In this paper, the model for sustainable urban water management and the design of the Sub-watershed level Urban Stormwater-Greywater Management System are described.

  1. Transpiration and root development of urban trees in structural soil stormwater reservoirs.

    Science.gov (United States)

    Bartens, Julia; Day, Susan D; Harris, J Roger; Wynn, Theresa M; Dove, Joseph E

    2009-10-01

    Stormwater management that relies on ecosystem processes, such as tree canopy interception and rhizosphere biology, can be difficult to achieve in built environments because urban land is costly and urban soil inhospitable to vegetation. Yet such systems offer a potentially valuable tool for achieving both sustainable urban forests and stormwater management. We evaluated tree water uptake and root distribution in a novel stormwater mitigation facility that integrates trees directly into detention reservoirs under pavement. The system relies on structural soils: highly porous engineered mixes designed to support tree root growth and pavement. To evaluate tree performance under the peculiar conditions of such a stormwater detention reservoir (i.e., periodically inundated), we grew green ash (Fraxinus pennsylvanica Marsh.) and swamp white oak (Quercus bicolor Willd.) in either CUSoil or a Carolina Stalite-based mix subjected to three simulated below-system infiltration rates for two growing seasons. Infiltration rate affected both transpiration and rooting depth. In a factorial experiment with ash, rooting depth always increased with infiltration rate for Stalite, but this relation was less consistent for CUSoil. Slow-drainage rates reduced transpiration and restricted rooting depth for both species and soils, and trunk growth was restricted for oak, which grew the most in moderate infiltration. Transpiration rates under slow infiltration were 55% (oak) and 70% (ash) of the most rapidly transpiring treatment (moderate for oak and rapid for ash). We conclude this system is feasible and provides another tool to address runoff that integrates the function of urban green spaces with other urban needs.

  2. Life-cycle Economic and Environmental Effects of Green, Gray and Hybrid Stormwater Infrastructure

    Science.gov (United States)

    Stokes-Draut, J. R.; Taptich, M. N.; Horvath, A.

    2016-12-01

    Cities throughout the U.S. are seeking efficient ways to manage stormwater for many reasons, including flood control, pollution management, water supply augmentation and to prepare for a changing climate. Traditionally, cities have relied primarily on gray infrastructure, namely sewers, storage and treatment facilities. In these systems, urban runoff, its volume increasing as impervious surfaces expand, is channeled to a wastewater plant where it is mixed with raw sewage prior to treatment or it is discharged, generally untreated, to local water bodies. These facilities are inflexible and expensive to build and maintain. Many systems are deteriorating and/or approaching, if not exceeding, their design capacity. Increasingly, more innovative approaches that integrate stormwater management into the natural environment and that make sense at both local and regional scales are sought. Identifying the best stormwater solution will require evaluating the life-cycle economic costs associated with these alternatives, including costs associated with construction, operation, and maintenance including regulatory and permitting costs, financing, as well as other indirect costs (e.g., avoided wastewater processing or system capacity expansion, increased property value) and non-economic co-benefits (i.e, aesthetics, habitat provision). Beyond conventional life-cycle costing, applying life-cycle assessment (LCA) will contribute to more holistic and sustainable decision-making. LCA can be used to quantitatively track energy use, greenhouse gas emissions, and other environmental effects associated with constructing, operating, and maintaining green and gray infrastructure, including supply chain contributions. We will present the current state of knowledge for implementing life-cycle costing and LCA into stormwater management decisions for green, gray and hybrid infrastructure.

  3. Cementitious porous pavement in stormwater quality control: pH and alkalinity elevation.

    Science.gov (United States)

    Kuang, Xuheng; Sansalone, John

    2011-01-01

    A certain level of alkalinity acts as a buffer and maintains the pH value in a stable range in water bodies. With rapid urban development, more and more acidic pollutants flow to watersheds with runoff and drop alkalinity to a very low level and ultimately degrade the water environment. Cementitious porous pavement is an effective tool for stormwater acidic neutralization. When stormwater infiltrates cement porous pavement (CPP) materials, alkalinity and pH will be elevated due to the basic characteristics of cement concrete. The elevated alkalinity will neutralize acids in water bodies and maintain the pH in a stable level as a buffer. It is expected that CPP materials still have a certain capability of alkalinity elevation after years of service, which is important for CPP as an effective tool for stormwater management. However, few previous studies have reported on how CPP structures would elevate runoff alkalinity and pH after being exposed to rainfall-runoff for years. In this study, three groups of CPP specimens, all exposed to rainfall-runoff for 3 years, were used to test the pH and alkalinity elevation properties. It was found that runoff pH values were elevated from 7.4 to the range of 7.8-8.6 after infiltrating through the uncoated specimens, and from 7.4 to 8.5-10.7 after infiltrating through aluminum-coated specimens. Runoff alkalinity elevation efficiencies are 11.5-14.5% for uncoated specimens and 42.2% for coated specimens. The study shows that CPP is an effective passive unit operation for stormwater acid neutralization in our built environment.

  4. Urban stormwater - greywater management system for sustainable urban water management at sub-watershed level

    Science.gov (United States)

    Singh Arora, Amarpreet

    2017-11-01

    Urban water management involves urban water supply (import, treatment and distribution of water), urban wastewater management (collection, treatment and disposal of urban sewage) and urban storm water management. Declining groundwater tables, polluted and declining sources of water, water scarcity in urban areas, unsatisfactory urban water supply and sanitation situation, pollution of receiving water bodies (including the ground water), and urban floods have become the concerns and issues of sustainable urban water management. This paper proposes a model for urban stormwater and sewage management which addresses these concerns and issues of sustainable urban water management. This model proposes segregation of the sewage into black water and greywater, and urban sub-watershed level stormwater-greywater management systems. During dry weather this system will be handling only the greywater and making the latter available as reclaimed water for reuse in place of the fresh water supply. During wet weather, the system will be taking care of (collection and treatment) both the storm water and the greywater, and the excess of the treated water will be disposed off through groundwater recharging. Application of this model in the Patiala city, Punjab, INDIA for selected urban sub-watersheds has been tried. Information and background data required for the conceptualization and design of the sub-watershed level urban stormwater-greywater management system was collected and the system has been designed for one of the sub-watersheds in the Patiala city. In this paper, the model for sustainable urban water management and the design of the Sub-watershed level Urban Stormwater-Greywater Management System are described.

  5. A Fuzzy Control System for Reducing Urban Runoff by a Stormwater Storage Tank

    Science.gov (United States)

    Zhang, P.; Cai, Y.; Wang, J.

    2017-12-01

    Stormwater storage tank (SST) is a popular low impact development technology for reducing stormwater runoff in the construction of sponge city. Most researches on SST were mainly the design, pollutants removal effect, and operation assessment. While there were few researches on the automatic control of SST for reducing peak flow. In this paper, fuzzy control was introduced into the peak control of SST to improve the efficiency of reducing stormawter runoff. Firstly, the design of SST was investigated. A catchment area and return period were assumed, a SST model was manufactured, and then the storage capacity of the SST was verified. Secondly, the control parameters of the SST based on reducing stormwater runoff was analyzed, and a schematic diagram of real-time control (RTC) system based on peak control SST was established. Finally, fuzzy control system of a double input (flow and water level) and double output (inlet and outlet valve) was designed. The results showed that 1) under the different return periods (one year, three years, five years), the SST had the effect of delayed peak control and storage by increasing the detention time, 2) rainfall, pipeline flow, the influent time and the water level in the SST could be used as RTC parameters, and 3) the response curves of flow velocity and water level fluctuated very little and reached equilibrium in a short time. The combination of online monitoring and fuzzy control was feasible to control the SST automatically. This paper provides a theoretical reference for reducing stormwater runoff and improving the operation efficiency of SST.

  6. Long-term hydraulic performance of stormwater infiltration systems:a field survey

    OpenAIRE

    Al-Rubaei, Ahmed; Engström, Malin; Viklander, Maria; Blecken, Godecke-Tobias

    2013-01-01

    This paper examined the factors influencing the long-term hydraulic performance of some stormwater infiltration systems (swale and two types of permeable pavements) in Växjö, southern Sweden. The infiltration capacities of 9 permeable pavements and 2 swales sites, all with different ages ranging from 1 year to 14 years, were measured using replicate double ring infiltrometers. The sites were either constructed of swale (2), interlocking concrete pavers (ICP) filled with gravel (2), concrete g...

  7. Final Environmental Assessment for Stormwater Drainage Project on F. E. Warren Air Force Base, Wyoming

    Science.gov (United States)

    2005-05-01

    not considered widely effective . Chemical Control Herbicides registered for control of Dalmatian toadflax include dicamba , 2,4-D, and picloram...WYOMING It is my decision to approve the Proposed Action as described in the Stormwater Drainage Project Environmental Assessment (EA), which is...mission effectiveness of FE Warren AFB while improving the level of safety for both personnel and property, on- and off-base, during major storm events

  8. Reflections on a Lifetime in Human Services and Mental Retardation

    Science.gov (United States)

    Wolfensberger, Wolf

    2011-01-01

    The author, a life member of the American Association on Mental Retardation, has reflected on over 30 years of primary engagement in mental retardation and inventoried what he believes are certain changes for the better and for the worse that have occurred since the 1950s as well as certain things that have not changed. Some action implications…

  9. Defining Mental Retardation: A Matter of Life or Death

    Science.gov (United States)

    Lichten, William; Simon, Elliot W.

    2007-01-01

    Because persons with mental retardation cannot be executed for murder, the diagnosis becomes a life and death matter. The American Association on Mental Retardation (now the American Association on Intellectual and Developmental Disabilities) and other associations agree that IQ alone is an insufficient criterion and adaptive functioning also…

  10. Obstetric interventions and perinatal asphyxia in growth retarded term infants

    DEFF Research Database (Denmark)

    Langhoff-Roos, J; Lindmark, G

    1997-01-01

    -fold (6-8%) for growth retarded infants both in SGA infants in general and infants with asymmetric body proportions. The immediate perinatal outcome, however, was favorable with Apgar below 8 at 5 min in only 2% irrespective of the type of growth retardation, in spite of the fact that less than 25...

  11. Neurotoxicity and risk assessment of brominated and alternative flame retardants

    NARCIS (Netherlands)

    Hendriks, Hester S; Westerink, Remco H S

    2015-01-01

    Brominatedflame retardants (BFRs) are widely used chemicals that prevent or slow the onset and spreading of fire. Unfortunately, many of these compounds pose serious threats for human health and the environment, indicating an urgent need for safe(r) and less persistent alternativeflame retardants

  12. Flame retardants: Dust - and not food - might be the risk

    NARCIS (Netherlands)

    de Boer, J.; Ballesteros-Gomez, A.M.; Leslie, H.A.; Brandsma, S.H.; Leonards, P.E.G.

    2016-01-01

    Flame retardants (FRs) are used to delay ignition of materials such as furniture and electric and electronic instruments. Many FRs are persistent and end up in the environment. Environmental studies on flame retardants (FRs) took off in the late 1990s. Polybrominated diphenylethers (PBDEs) appeared

  13. Environmental fate & effects of new generation flame retardants

    NARCIS (Netherlands)

    Waaijers, S.L.

    2014-01-01

    There is a pressing need for substituting several halogenated flame retardants, given the human and environmental health concerns of many of these compounds. Halogen Free Flame Retardants (HFFRs) have been suggested as alternatives and are already being marketed, although their potential impact on

  14. Mental Retardation and the Neglected Construct of Motivation.

    Science.gov (United States)

    Switzky, Harvey N.

    1997-01-01

    Argues that an educational definition of mental retardation has to be sensitive to the motivational self-system and the self-regulatory processes that underpin performance of students with mental retardation. The theory of motivational orientation that explains the differences in students with intrinsic motivation or extrinsic motivation is…

  15. Defining Mental Retardation and Ensuring Access to the General Curriculum.

    Science.gov (United States)

    Wehmeyer, Michael L.

    2003-01-01

    Discussion of trends in the American Association on Mental Retardation's definition of mental retardation notes a shift toward a support paradigm and a definition stressing the interaction between a person's independent functioning and the various contexts of the person's life. The current definition is seen to promote greater access to the…

  16. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    Spot heating; overloading; fatigue crack growth retardation; residual stress; delay cycles. ... It is observed that the extent of crack growth retardation increases with increasing level of overload as well as with increasing spot temperature. It is also ... Manuscript received: 29 November 2001; Manuscript revised: 24 June 2002 ...

  17. Adaptive Behavior Malingering in Legal Claims of Mental Retardation

    Science.gov (United States)

    Kadlubek, Renee Marie

    2012-01-01

    In 2002, the Supreme Court ruled that it is unconstitutional to put people with mental retardation to death for capital crimes ("Atkins v. Virginia," 2002). Justice Scalia dissented, suggesting that mental retardation is a condition easy to feign. The current study examined whether participants provided with the definition of mental…

  18. Muscle Fatigue during Intermittent Exercise in Individuals with Mental Retardation

    Science.gov (United States)

    Zafeiridis, Andreas; Giagazoglou, Paraskevi; Dipla, Konstantina; Salonikidis, Konstantinos; Karra, Chrisanthi; Kellis, Eleftherios

    2010-01-01

    This study examined fatigue profile during intermittent exercise in 10 men with mild to moderate mental retardation (MR) and 10 men without mental retardation (C). They performed 4 x 30 s maximal knee extensions and flexions with 1-min rest on an isokinetic dynamometer. Peak torque of flexors (PTFL) and extensors (PTEX), total work (TW), and…

  19. 38 CFR 4.127 - Mental retardation and personality disorders.

    Science.gov (United States)

    2010-07-01

    ... personality disorders. 4.127 Section 4.127 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... and personality disorders. Mental retardation and personality disorders are not diseases or injuries... superimposed upon mental retardation or a personality disorder may be service-connected. (Authority: 38 U.S.C...

  20. Sex between persons with 'mental retardation': an ethical evaluation

    NARCIS (Netherlands)

    Spiecker, B.; Steutel, J.W.

    2002-01-01

    Is sex between people with "mental retardation" morally permissible and, if at all, under what conditions? This paper tries to answer this question, but only with regard to sex between biologically mature individuals with mild or moderate mental retardation. First, the concepts of "sexual activity"