Sample records for ray county dam

  1. Allegheny County Dam Locations

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset shows the point locations of dams in Allegheny County. If viewing this description on the Western Pennsylvania Regional Data Center’s open data portal...

  2. Douglas County Dam Breach Inundation Areas

    Kansas Data Access and Support Center — Dam breach analysis provides a prediction of the extent and timing of flooding from a catastrophic breach of the dams. These results are sufficient for developing...

  3. National Dam Safety Program. Woodridge Lake Dam (MO 11005), Mississippi - Kaskaskia - St. Louis Basin, Warren County, Missouri. Phase I Inspection Report.


    KASKASKIA. ST. LOUIS BAS WOODRIDGE LAKE DAM WARREN COUNTY, MISSOURI MO 11005 (9) Final rept., DACW43-79-C.-#A)75 J (i) Sep 79 (10) Walter G. /Shifrin...Dam Inspection Report National Dam Safety Program Final Report Woodridge Lake Dam (MO 11005) 6. PERFORMING ORG. REPORT NUMBER Warren County, Missouri 7...Norvell Construction of 3320 Hermoso St., St. Louis, MO. After the structure was completed, a 2 inch water- line with a water faucet was installed on the

  4. Dam Inventory, dams, Published in 2009, 1:24000 (1in=2000ft) scale, Washington County.

    NSGIC GIS Inventory (aka Ramona) — This Dam Inventory dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2009. It is described as 'dams'. Data...

  5. National Dam Inspection Program. Edgewater Village (NDI-ID Number MD-83), Bush River Basin, Unnamed Tributary of Otter Point Creek, Harford County, Phase I Inspection Report,


    features of the dam. d. Seismic Stability. The dam is located in Seismic Zone 1; and, based on visual observation, the static stability of the dam...EDGEWATER VILLAGE DAM ’LOGIC NAP OF HANFORD COUNTY,GELG MA PNPAIEI BY STATE OF MARYLAND,GEL YMA MARYLAND GEOLOGIC SURVEY,EL K PER& AH RMEL KLPER&_A

  6. The Prado Dam and Reservoir, Riverside and San Bernardino Counties, California


    vireo, a migratory bird living in the trees of the Prado Basin ( Beeman 1985). The vireo has since been officially listed as endangered, and the Basin has...Army Corps of Engineers, Los Angeles. Beeman , D. 1985 Vireo May Endanger Prado Dam Raising. Press-Enterprise, August 9. On file, Heritage Room, Corona...Use of Federal Lands in Prado Flood Control Basin, by Max Bookman and Donald M. Baker. On file, Orange County Environmental Management Agency Library

  7. 75 FR 15458 - Request for Small Reclamation Projects Act Loan To Construct Narrows Dam in Sanpete County, UT


    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Reclamation Request for Small Reclamation Projects Act Loan To Construct Narrows Dam in Sanpete County, UT AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of Availability and Notice of...

  8. Dam Inventory, diversion dams, Published in 2009, 1:24000 (1in=2000ft) scale, Washington County.

    NSGIC GIS Inventory (aka Ramona) — This Dam Inventory dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2009. It is described as 'diversion...

  9. 76 FR 20707 - Cle Elum Dam Fish Passage Facilities and Fish Reintroduction Project; Kittitas County, WA


    ... Bureau of Reclamation Cle Elum Dam Fish Passage Facilities and Fish Reintroduction Project; Kittitas... Environmental Impact Statement (FEIS) for the Cle Elum Dam Fish Passage Facilities and Fish Reintroduction... FEIS on the proposed Cle Elum Dam Fish Passage Facilities and Fish Reintroduction Project....

  10. National Dam Safety Program. Lake Lafayette Dam (MO 20415), Missouri - Kansas City Basin, Lafayette County, Missouri. Phase I Inspection Report.


    lake used for recrea- tion. g. Design and Construction History . The dam was designed by Kennoy Engineers, Inc., 3367 Tates Creek Pike, Lexington...coo rmoooeo,,oooocoe.-.. 0Oa,0 ~OO4W 00 * an OCOCCO L.a C.r.C en to to.. taD c.a 000Cc-co CacaO 00CC, tat coo COOt coca CC) CCC 0)’ * * 0 * W~ ~ * S

  11. Effects of removing Good Hope Mill Dam on selected physical, chemical, and biological characteristics of Conodoguinet Creek, Cumberland County, Pennsylvania

    Chaplin, Jeffrey J.; Brightbill, Robin A.; Bilger, Michael D.


    The implications of dam removal on channel characteris-tics, water quality, benthic invertebrates, and fish are not well understood because of the small number of removals that have been studied. Comprehensive studies that document the effects of dam removal are just beginning to be published, but most research has focused on larger dams or on the response of a sin-gle variable (such as benthic invertebrates). This report, pre-pared in cooperation with the Conodoguinet Creek Watershed Association, provides an evaluation of how channel morphol-ogy, bed-particle-size distribution, water quality, benthic inver-tebrates, fish, and aquatic habitat responded after removal of Good Hope Mill Dam (a small 'run of the river' dam) from Conodoguinet Creek in Cumberland County, Pa. Good Hope Mill Dam was a 6-foot high, 220-foot wide concrete structure demolished and removed over a 3-day period beginning with the initial breach on November 2, 2001, at 10:00 a.m. eastern standard time. To isolate the effects of dam removal, data were collected before and after dam removal at five monitoring stations and over selected reaches upstream, within, and downstream of the impoundment. Stations 1, 2, and 5 were at free-flowing control locations 4.9 miles upstream, 2.5 miles upstream, and 5 miles downstream of the dam, respec-tively. Stations 3 and 4 were located where the largest responses were anticipated, 115 feet upstream and 126 feet downstream of the dam, respectively Good Hope Mill Dam was not an effective barrier to sedi-ment transport. Less than 3 inches of sediment in the silt/clay-size range (less than 0.062 millimeters) coated bedrock within the 7,160-foot (1.4-mile) impoundment. The bedrock within the impoundment was not incised during or after dam removal, and the limited sediment supply resulted in no measurable change in the thalweg elevation downstream of the dam. The cross-sec-tional areas at stations 3 and 4, measured 17 days and 23 months after dam removal, were within

  12. Dam Inventory, Published in 2007, 1:2400 (1in=200ft) scale, Polk County, Wisconsin.

    NSGIC GIS Inventory (aka Ramona) — This Dam Inventory dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2007. Data by this publisher are...

  13. Dam Inventory, reservoirs, Published in 2006, 1:24000 (1in=2000ft) scale, Washington County.

    NSGIC GIS Inventory (aka Ramona) — This Dam Inventory dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2006. It is described as 'reservoirs'....

  14. Dam Inventory, Dams in 9 county region in South Georgia, Published in 2006, 1:2400 (1in=200ft) scale, Southern Georgia Regional Commission.

    NSGIC GIS Inventory (aka Ramona) — This Dam Inventory dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Field Survey/GPS information as of 2006. It is described as 'Dams...

  15. Geophysical and hydrologic analysis of an earthen dam site in southern Westchester County, New York

    Chu, Anthony; Stumm, Frederick; Joesten, Peter K.; Noll, Michael L.


    Ninety percent of the drinking water for New York City passes through the Hillview Reservoir facility in the City of Yonkers, Westchester County, New York. In the past, several seeps located downslope from the reservoir have flowed out from the side of the steepest slope at the southern end of the earthen embankment. One seep that has been flowing continuously was discovered during an inspection of the embankment in 1999. Efforts were made in 2001 to locate the potential sources of the continuous flowing seep. In 2005, the U.S. Geological Survey, in cooperation with the New York City Department of Environmental Protection, began a cooperative study to investigate the relevant hydrogeologic framework to characterize the local groundwater-flow system and to determine possible sources of the seeps. The two agencies used hydrologic and surface geophysical techniques to assess the earthen embankment of the Hillview Reservoir. Between April 1, 2005 and March 1, 2008, water levels were measured manually each month at 46 wells surrounding the reservoir, and flow was measured monthly at three of the five seeps on the embankment. Water levels were measured hourly in the East Basin of the reservoir, at 24 of 46 wells, and discharge was measured hourly at two of the five seeps. Slug tests were performed at 16 wells to determine the hydraulic conductivity of the geologic material surrounding the screened zone. Estimated hydraulic conductivities for 25 wells on the southern embankment ranged from 0.0063 to 1.2 feet per day and averaged 0.17 foot per day. The two-dimensional resistivity surveys indicate a subsurface mound of electrically conductive material (low-resistivity zone) beneath the terrace area (top of dam) surrounding the reservoir with a distinct elevation increase closer to the crest. Two-dimensional shear wave velocity surveys indicate a similar structure of the high shear wave velocity materials (high-velocity zone), increasing in elevation toward the crest and

  16. Grand Coulee Dam Wildlife Mitigation Program : Pygmy Rabbit Programmatic Management Plan, Douglas County, Washington.

    Ashley, Paul


    The Northwest Power Planning Council and the Bonneville Power Administration approved the pygmy rabbit project as partial mitigation for impacts caused by the construction of Grand Coulee Dam. The focus of this project is the protection and enhancement of shrub-steppe/pygmy rabbit habitat in northeastern Washington.

  17. Effective mitigation of debris flows at Lemon Dam, La Plata County, Colorado

    deWolfe, V.G.; Santi, P.M.; Ey, J.; Gartner, J.E.


    To reduce the hazards from debris flows in drainage basins burned by wildfire, erosion control measures such as construction of check dams, installation of log erosion barriers (LEBs), and spreading of straw mulch and seed are common practice. After the 2002 Missionary Ridge Fire in southwest Colorado, these measures were implemented at Knight Canyon above Lemon Dam to protect the intake structures of the dam from being filled with sediment. Hillslope erosion protection measures included LEBs at concentrations of 220-620/ha (200-600% of typical densities), straw mulch was hand spread at concentrations up to 5.6??metric tons/hectare (125% of typical densities), and seeds were hand spread at 67-84??kg/ha (150% of typical values). The mulch was carefully crimped into the soil to keep it in place. In addition, 13 check dams and 3 debris racks were installed in the main drainage channel of the basin. The technical literature shows that each mitigation method working alone, or improperly constructed or applied, was inconsistent in its ability to reduce erosion and sedimentation. At Lemon Dam, however, these methods were effective in virtually eliminating sedimentation into the reservoir, which can be attributed to a number of factors: the density of application of each mitigation method, the enhancement of methods working in concert, the quality of installation, and rehabilitation of mitigation features to extend their useful life. The check dams effectively trapped the sediment mobilized during rainstorms, and only a few cubic meters of debris traveled downchannel, where it was intercepted by debris racks. Using a debris volume-prediction model developed for use in burned basins in the Western U.S., recorded rainfall events following the Missionary Ridge Fire should have produced a debris flow of approximately 10,000??m3 at Knight Canyon. The mitigation measures, therefore, reduced the debris volume by several orders of magnitude. For comparison, rainstorm

  18. Effective mitigation of debris flows at Lemon Dam, La Plata County, Colorado

    deWolfe, Victor G.; Santi, Paul M.; Ey, J.; Gartner, Joseph E.


    To reduce the hazards from debris flows in drainage basins burned by wildfire, erosion control measures such as construction of check dams, installation of log erosion barriers (LEBs), and spreading of straw mulch and seed are common practice. After the 2002 Missionary Ridge Fire in southwest Colorado, these measures were implemented at Knight Canyon above Lemon Dam to protect the intake structures of the dam from being filled with sediment. Hillslope erosion protection measures included LEBs at concentrations of 220-620/ha (200-600% of typical densities), straw mulch was hand spread at concentrations up to 5.6 metric tons/hectare (125% of typical densities), and seeds were hand spread at 67-84 kg/ha (150% of typical values). The mulch was carefully crimped into the soil to keep it in place. In addition, 13 check dams and 3 debris racks were installed in the main drainage channel of the basin. The technical literature shows that each mitigation method working alone, or improperly constructed or applied, was inconsistent in its ability to reduce erosion and sedimentation. At Lemon Dam, however, these methods were effective in virtually eliminating sedimentation into the reservoir, which can be attributed to a number of factors: the density of application of each mitigation method, the enhancement of methods working in concert, the quality of installation, and rehabilitation of mitigation features to extend their useful life. The check dams effectively trapped the sediment mobilized during rainstorms, and only a few cubic meters of debris traveled downchannel, where it was intercepted by debris racks. Using a debris volume-prediction model developed for use in burned basins in the Western U.S., recorded rainfall events following the Missionary Ridge Fire should have produced a debris flow of approximately 10,000 m 3 at Knight Canyon. The mitigation measures, therefore, reduced the debris volume by several orders of magnitude. For comparison, rainstorm-induced debris

  19. National Dam Safety Program. Lock 4 Embankment Waterford Flight Dam (Inventory Number N.Y. 968). Mohawk River Basin, Saratoga County, New York. Phase I Inspection Report,


    ENGINEERING DATA 2.1 GEOTECHNICAL DATA a. Geology Lock 4 Embankment Waterford Flight Dam is located in the Hudson Valley section of the Valley and Ridge...River are controlled by the up- stream locks (Nos. 5 and 6) and by the Crescent Dam which forms the im- poundment for the navigation channel above Lock...River above Crescent Dan may contribute flow through the canal system. b. Discharge at Dam Site JNo discharge records are available for this site

  20. National Dam Safety Program. Von Der Ahe Dam (MO 31077), Mississippi - Kaskaskia - St. Louis Basin, Franklin County, Missouri. Phase I Inspection Report.


    from Controlling Office) IS. SECURITY CLASS. (of thia rePort) National Darn Safety Program. Von der UNLSSFE(~ Ahe Dam (MO 31V77), Mississippi - ISa ...34;TAT1 MiNT I Apro’,,,, for ;,.blhc yele(so |: ’ --- __ ~ ~~ii[ , - rtu : ’ lrrJl": ’,d PHASE I REPORT NATIONAL DAM SAFETY PROGRAM Name of Dam: Von Der Ahe

  1. National Dam Safety Program. Lac Marseilles Dam (MO 30282), Mississippi - Kaskaskia - St. Louis Basin, St. Francois County, Missouri. Phase I Inspection Report.


    DACW4-81--OJTnTA 9. PERFORMING ORGANIZATION NAME AND ADDRESS TAREA WORK UNIT NUMBERS K U.S. Army Engineer District, St. Louis Dam Inventory and...The dam was constructed without a set of plans or "as built" records, but we understand that its construction was observed and directed by a...Drainage Basin and Site Topography 3A. Plan and Crest Profile of Dam 3B. Sections of Dam and Spillway 4. Regional Geologic Map APPENDICES A Figure A-I

  2. National Dam Safety Program. Hilliard Estates Lake Dam (MO 20473), Osage - Gasconade River Basin, Greene County, Missouri. Phase I Inspection Report.


    Tributary of the Little Pomme de Terre Date of Inspection: November 19, 1980 Hlilliard Estates Lake Dam was inspected by an interdiscip)- linary team... Terre River. The dam and lake are within the Strafford, Missouri 7.5 minute quadrangle sheet (Section 15, T3ON, R20W - latitude 37°19.1’ longitude

  3. National Dam Safety Program. Deimeke Lake Dam (MO 11163), Mississippi - Salt - Quincy River Basin, Audrain County, Missouri. Phase I Inspection Report.


    1980 Dam Inventory and Inspection Section, LMSED-PD 13. NUMBER OF PAGES 210 Tucker Blvd., North, St. Louis, Mo. 63101 Approximately 80 T4. MONITOR -J I K LA EDA Ou113 PLA AN LVTO -- PLATE 3 RESERVOIR WArER SURFACE TOP OF DAM, EL. 773 (ASSUMED) ON JULY 1, 1980, EL

  4. National Dam Safety Program. Lake Montowese Dam (M0 30151), Mississippi - Kaskaskia - St. Louis Basin, Jefferson County, Missouri. Phase I Inspection Report.


    including installation of the casing pipe and grouting of the annular space about the carrier pipes, was performed under subcontract by the I Karston...inch diameter steel casing pipe extending through the dam and under the road downstream of the I dam. Due to the fact that the piping on the upstream

  5. High resolution transmission soft X-ray microscopy of deterioration products developed in large concrete dams

    Kurtis; Monteiro; Brown; Meyer-Ilse


    In concrete structures, the reaction of certain siliceous aggregates with the highly alkaline concrete pore solution produces an alkali-silicate gel that can absorb water and expand. This reaction can lead to expansion, cracking, increased permeability, and decreased strength of the concrete. Massive concrete structures, such as dams, are particularly susceptible to the damage caused by the alkali-silica reaction because of the availability of water and because massive gravity dams usually do not contain steel reinforcement to restrain the expansion. Both the cement hydration products and alkali-silica reaction products are extremely sensitive to humidity. Consequently, characterization techniques that require high vacuum or drying, as many existing techniques do, are not particularly appropriate for the study of the alkali-silica reaction because artefacts are introduced. Environmental scanning electron micrographs and scanning electron micrographs with energy dispersive X-ray analysis results demonstrate the effect of drying on the morphology and chemical composition of the alkali-silicate reaction gel. Thus, the impetus for this research was the need to observe and characterize the alkali-silica reaction and its gel product on a microscopic level in a wet environment (i.e. without introducing artefacts due to drying). Only soft X-ray transmission microscopy provides the required high spatial resolution needed to observe the reaction process in situ. The alkali-silica reaction can be observed over time, in a wet condition, and at normal pressures, features unavailable with most other high resolution techniques. Soft X-rays also reveal information on the internal structure of the sample. The purpose of this paper is to present research, obtained using transmission soft X-ray microscopy, on the effect of concrete pore solution cations, namely sodium and calcium, on the product formed as a result of alkali attack. Alkali-silicate reaction (ASR) gel was obtained from

  6. National Dam Safety Program. Lake Scheffborg Dam (MO 31442), Lake Lucern Dam (MO 30519) and Lake Innsbrook Dam (MO 11243), Missouri - Kansas City Basin, Warren County, Missouri. Phase I Inspection Report.


    PROFILE 8 CROSS-SECTION Horner ,Shifrin,inc. August 1980 - PLATE 9 SPILLWAY OUTLET CHANNEL D OVERFLOW VA 26 CHANNEL ROCK2 FALLS 3 28 3 12-"$ SEEL paragraph 2, above. c. The discharges for the principal and emergency spillways for like elevations were sunmmated for entry on the Y4 and Y5 cards...emergency spillways for like elevations were sunmated for entry on the Y4 and Y5 cards. 5. Spillway capacities for the various dams upstream of the

  7. Geologic map of the Cochiti Dam quadrangle, Sandoval County, New Mexico

    Dethier, David P.; Thompson, Ren A.; Hudson, Mark R.; Minor, Scott A.; Sawyer, David A.


    The Cochiti Dam quadrangle is located in the southern part of the Española Basin and contains sedimentary and volcanic deposits that record alluvial, colluvial, eolian, tectonic and volcanic processes over the past seventeen million years. The geology was mapped from 1997 to 1999 and modified in 2004 to 2008. The primary mapping responsibilities were as follows: Dethier mapped the surficial deposits, basin-fill sedimentary deposits, Miocene to Quaternary volcanic deposits of the Jemez volcanic field, and a preliminary version of fault distribution. Thompson and Hudson mapped the Pliocene and Quaternary volcanic deposits of the Cerros del Rio volcanic field. Thompson, Minor, and Hudson mapped surface exposures of faults and Hudson conducted paleomagnetic studies for stratigraphic correlations. Thompson prepared the digital compilation of the geologic map.

  8. Dam Inventory, Dams - data provided by the state, Published in 2010, 1:2400 (1in=200ft) scale, Effingham County Board Of Commissioners.

    NSGIC GIS Inventory (aka Ramona) — This Dam Inventory dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Published Reports/Deeds information as of 2010. It is described...

  9. National Dam Inspection Program. Bradley Lake Dam (Inventory NY 00755). Lower Hudson River Basin. City of Troy Rensselaer County, New York. Phase I Inspection Report,


    There is seepage into the con- duit upstream of the dam crest and stalactites of calcium carbonate hang from the crown of the conduit (see Photo A-9B...for Additional Investigations The following investigations should be performed by a registered professional engineer qualified by training and... training and exper- ience in the design of dams. Assistance by such an engineer may also be useful for some of the other work. a. Complete

  10. National Dam Safety Program. Lake Carmel Dam (Inventory Number N.Y. 100), Lower Hudson River Basin, Putnam County, New York. Phase I Inspection Report,


    proposed dam will rest is (clay, sand, gravel, boulders, granite, shale , slate, limestone, etc.) .. ... . A . --m..--tr ......composing 13...clay, sand, gravel, boulders, S granite, shale , sl.te, lim estone, etc...Civil En.,inoor JEPui .Lf... E-wigs CARNiI 5.3312 SumoIVIGION PLANNING SANITATION DAM DESIGN CONST’RUCTION ROY BURGESS 5eaLIFICATION4a PRFESIONAL BLDG

  11. National Dam Safety Program. Potake Lake Dam (Inventory Number N.Y. 970), Passaic River Basin, Lower Hudson River Area, Rockland County, New York. Phase I Inspection Report,


    Highlands are characterized by strong topo- graphic linearity in which the majority of the ridges and valleys follow the northwest-southwest strike of the...I I POTAKE -N- ~- POND DAM DeSe 4 - 0 .4 u 4e S / /4 ~ ~ i~ ;3Mi -N. ,f c ,,--POAK PO DAM’ -ce - a-6 ~ - ~~-T- - ’e,-- ~~~ TRONEDM .7-L[(74 . ’V Shppr

  12. 75 FR 5626 - Cle Elum Dam Fish Passage Facilities and Fish Reintroduction Project; Kittitas County, WA INT-DES...


    ... Bureau of Reclamation Cle Elum Dam Fish Passage Facilities and Fish Reintroduction Project; Kittitas...) announcing the commencement of work under the National Environmental Policy Act (NEPA) on the Cle Elum Dam... upstream adult fish passage facilities at the dam, as well as analyses associated with the...

  13. National Dam Safety Program. Lake Stockholm Dam (NJ 00302), Passaic River Basin, Small Branch, Passaic County, New Jersey. Phase I Inspection Report.


    been classified as having “High Hazard Potential” on the basis that failure of the dam would cause excessive property damage to residences downstream...and could potentially cause more than a few deaths. Visual inspection of the downstream area shows that breach of the dam would cause little damage...L ~ .~ tI-, _______ DATE I~ 7 .73 Li. k~~~ L .1 a ’ u s-. JOB NO. ~J’ 7~ ~ p CKD ~~~~) DATE L-bz?~L SHEET NO. ‘ OF ID I- ‘Cz~- I— 0 0 CL

  14. National Dam Safety Program. Lake Flower Dam, Inventory Number NY-707. Lake Champlain River Basin. Franklin County, New York. Phase I Inspection Report,


    boulders and & ravel . 1io rook in vicinity~of dam. 1 (6) Dlt.lwaY and a~ron, Spillway, 46’ long. Sluiceway, 12’ wideby 3’ deep. (7) Other disciiare, Two po...Agriculture Soil Conservation Service. On June 3, 1977, Mr. Steven Maurice and Mr. Steven Payne of the Soil Conservation Service came to Saranac Lake...Conservation District for approval by their executive council. Mr. Maurice mentioned that you had made an inspection of the dam in December of 1971, and at

  15. National Dam Safety Program. Stubblefield Lake Dam (MO 30363), Mississippi - Kaskaskia - St. Louis River Basin, Crawford County, Missouri. Phase I Inspection Report.


    appropriate corporate division, school, laboratory, etc., of the author. List city, state, and ZIP Code. Block 10 Program Element, Project, Task Area, and Work...INVENTORY NO. 30363 PEASE 1 INSPECION REPRT~ NATIONAL DAM SAETY PROGRAM Prepared By Anderson Engineering, Inc., Springfield, Missouri Hanson Engineers, Inc

  16. National Dam Safety Program. Alder Pond Dam (Inventory Number N.Y. 1489), Black River Basin, Oneida County, New York. Phase I Inspection Report,



  17. National Dam Safety Program. Little Choconut Watershed Site 2A Dam (Inventory Number NY 720), Susquehanna River Basin, Broome County, New York. Phase I Inspection Report,


    in the Choco - nut and Susquehanna valleys. Till, associated with theI glacial advance, mantles the rest of the site. b. Subsurface Investigations 1...basis of the visual examination, the Little Choco - nut Watershed Site 2A Dam is considered to be in good condition. There were no signs of impending

  18. National Dam Safety Program. Silver Lake Dam (Inventory Number VA 16508). Potomac River Basin, Rockingham County, Virginia. Phase I Inspection Report.


    investigations, testing, and detailed computational evaluations are beyond the scope of a Phase I investigation; however, the investigation is intended to...NATIONAL DAM SAFETY PRGRAM .. For Aldc S f~ ’,/~ / ZTXS GRIA&I’ ’ ’, ’-t ’ lIncedI Jsti ficatio "--- - . - .’i -, ! Aval and/or Dist.I special...mapping, subsurface investigations, testing, and detailed computational evaluations are beyond the scope of a Phase I Investigation; however, the

  19. National Dam Safety Program. General American Life Insurance Co. Lake Dam (MO 31390), Upper Mississippi - Kaskaskia - St. Louis Basin, St. Louis County, Missouri. Phase I Inspection Report.


    spillway, where a MIM ---- - -- timber footbridge about 4 feet wide and 40 feet long spans the outlet. A site plan of the General American Life Insurance...attractive if the normal waterline were 1 foot higher than originally planned. It appears that the footbridge that crosses the spillway structure was also...herein (curb, footbridge , and drawdown pipe screen) and the fact that the downstream slope of the dam was found to be somewhat steeper than specified

  20. National Dam Safety Program. Lake Valentine Dam (NJ00297) Delaware River Basin, Branch of the Pequest River, Sussex County, New Jersey. Phase 1 Inspection Report.



  1. National Dam Safety Program. Mach Lake Dam (MO 30133), Mississippi - Kaskaskia - St. Louis River Basin, Perry County, Missouri. Phase I Inspection Report.


    embankment was in fair condition. Deficiencies vilcuallv Ubse (rvrd by the inspection team were: (1) brUSh and briar ’rowth on upf [rem and~ rdownst-r-tm face...The slopes of the embankment were briar and )rush covered. Several ]is.. (12 to 15 inches diameter) tree stumps were noted on the upstream fare. No...perfriri ILV ai(n ~er~Me 0 in the construction of dams. (2) The slough area at midhei’Lht on rhe do)wustfre--ir fiS o Sa 1 (3) The briar and brush

  2. National Dam Safety Program. Lake Windsor Dam (NJ-00034), Hudson River Basin, Tributary Papakating Creek, Sussex County, New Jersey. Phase I Inspection Report.


    Potential." Visual inspection of the downstream area shows that breach of the dam would cause little damage to downstream residences which are...Le Novo( ~OIP o. a p" ,,_ _,_ o= (T ]l,4oo7/-2 4; J r ./0 /000 , By~ DATE1’V2.3Z oe -No. Igo JO CKD A~ DATE ____________SHEETNOOF LANGAN ENGINEERING...JOB NO. 4AZY , CKD -" - DATE3,tl/& SHEET NOJ.. OF. 10~ NN r Q ~Zf) A)i~ JO N O. .. ey WA... DATE JOBL " - ""~ HE NO. oJ2. loo ’.4 ~ye 41P~4~’ S

  3. Individual Target Data-Collection Points Upstream of the Siltation Dam at Prairie Rose Lake, Shelby County, Iowa

    U.S. Geological Survey, Department of the Interior — Point coverage of bathymetry target points upstream of the siltation dam at Prairie Rose Lake in Shelby Co., Iowa. The U.S. Geological Survey conducted a...

  4. 西吉县淤地坝工程建设现状与分析%Status and Analysis of Engineering Construction of Silt Dams in Xiji County



    There are 26 silt dams of dilapidated silt dam reinforcement and repair engineering in Xiji County, control area of 237.05km2, total storage capacity of 35,332,900 m3, choked with silt of 12,558,100. m3 and choked with soil of 180.28hm2; The construction of silt dams dredges regional traffic to a certain degree, which solves the problem of difficulty in drinking water for local people and develops irrigated land, laying a solid foundation for the local people to become rich.%西吉县病险淤地坝加固维修工程加固维修的淤地坝有26座,控制面积237.05km2,总库容3533.29万m3,已淤库容1255.81万m3,已淤地180.28hm2;这些淤地坝的建设,在一定程度上疏通了区域内的交通,解决当地群众的吃水难问题,发展水浇地,为当地群众脱贫致富奠定了坚实的基础.

  5. National Dam Safety Program. Cole Lake Dam (MO 30440), Mississippi - Kaskaskia - St. Louis Basin, Jefferson County, Missouri. Phase I Inspection Report.


    nqf: lie w ith in the pe leflood dian ie ?.ae , ’it 1 5, recommfenled chat the ;pi 1 way for this dam or1 edfor the PMF, The Prol rable Max muni Plot; 1. oit li r-:fi Iti nq from a :-,Lirn ot’ PMF m:)qtituode. ’The prhip, I! yd i w y ic a icqpi t.- Ito pan; tW. Q K - twtf ow r(eau It1 nq from...34hi :1 in: f:1 The emnil k ’tient ha!o an upo ;treaTj ci ene alo the witerlin<) of lv cn ) .7h, o crest width .)I tl mt 12 faend an rreqctld r ’lowin

  6. National Program of Inspection of Non-Federal Dams, Tennessee. Spring Lake Dam (Candlewood II) Old Hickory Dam (Candlewood III) (Inventory Numbers TN 06930 & TN 06926), Hatchie River Basin, near Saulsbury, Hardeman County, Tennessee. Phase I Investigation Report,


    20314. 1.3 Past Inspections - Past inspections of Spring Lake and Old Hickory Lake Dams include cursory inspections by George Moore and Troy Wedekind of...aertificate Cursory Preliminary Site Review Damage Potential Category:One Two Three Undetermined Inspection by: George Moore and Troy Wedekind Inspection...Cursory Preliminary Site Review Damage Potential Category:One Two Three __ Undetermined Inspection by: George Moore and Troy Wedekind Inspection Results

  7. National Dam Safety Program. Elm Creek Dam (Dam Number 16), (Inventory Number N.Y. 593), Conewango Creek Watershed, Allegheny River Basin, Cattaraugus County, New York. Phase I Inspection Report,


    Inspection Personnel Mr. Bob Farrell, Mr. Ken Avery, Mr. James Reynolds, Mr. Jeff Hardin c. Persons Contacted (including Address & Phone No.) U.S...CEAALL (4 AV; o n ; A 1.. V iz FODAE RETARD.IN. DAMVti.. ELM CREEK1 A. CI1 CATTARAUGUS COUNTY, NEW YORK RISER -CRADLE -COLLAR DETAILS ~,L! U.S

  8. National Dam Inspection Program. Beaver Lake Lodge Dam (NDI I.D. Number PA-00300, PennDER I.D. Number 52-93), Delaware River Basin, Raymondskill Creek, Pike County, Pennsylvania. Phase I Inspection Report,


    FIGURES APPENDIX F - GEOLOGY PHASE I INSPECTION REPORT NATIONAL DAM INSPECTION PROGRAM BEAVER LAKE LODGE DAM NDI NO. PA-00300, PENNDER NO. 52-93...Tavern Pond. The facilities on Dwarfskill Creek are Crescent Lake Dam and Gold Key Lake. Log Tavern Pond and Gold Key Lake are both natural lakes with no...Figure 2). e. Downstream Channel. Discharges from both spillways at Beaver Lake Lodge Dam flow through a comparatively flat valley for a distance of

  9. National Dam Inspection Program. Saxe Pond Dam (NDI I.D. Number PA-729, DER ID Number 8-10) Susquehanna River Basin. North Branch Mehoopany Creek, Bradford County, Pennsylvania. Phase I Inspection Report,


    formations and the Catskill Formation between them belong to the Susquehanna Group of Upper Devonian Age. They consist of sandstones, shales , and...1; 1. I)If *~~~~~ C iy GEOLOGIC MAP OF AREA AROUND SAXE POND DAM, ROSCOE BURGESS DAM AND THE BIRCH CREEK DAM SCALE 1:250,000 PENNSvVANIAN DEVONIAN

  10. Ornithological researches on the Goleşti Dam Lake (Argeş county, Romania during 2003 - 2010

    Denisa CONETE


    Full Text Available 199 bird species were observed in the Goleşti Dam Lake, from the middle hydrographical basin of the Argeş River, during 2003 – 2010 (minimum – 64 in January and maximum – 141 in April. Their distribution regarding the constancy, dominancy and Dzuba index of ecological signification were considered. There are two eudominant species (Anas platyrhynchos and Aythya ferina and two dominant species (Aythya fuligula and Larus ridibundus. The variation in the number of individuals during the year is strongly determined by the temperature variation that leads to the diminishing or increasing of the food resources. In winter, when the temperatures were low in the north (and the waters froze, the birds arrived in great number in our area but only a few of them remained in the area for breeding.

  11. Dams (National)

    Department of Transportation — This map layer portrays major dams of the United States, including Puerto Rico and the U.S. Virgin Islands (NTAD 2015). The map layer was created by extracting dams...

  12. National Dam Inspection Program. Lake Jean Dam. (NDI I.D. Number PA-00570 PennDER I.D. Number 40-16) Susquehanna River Basin, Branch of Kitchen Creek, Luzerne County, Pennsylvania. Phase I Inspection Report,


    12 5.4 Method of Analysis .... ............... 12 5.5 Summary of Analysis .... ............. ... 12 5.6 Spillway Adequacy ................. 14 SECTION...freeboard available for the main dam spillway. 5.4 Method of Analysis. The facility has been analyzed in accordance with the procedures and guidelines...Ok i11. IQ=~ - D3I. -3 -RT A r - - -z 10,3 90 T IQ Q -C -. la so0 IOIT 3I 0, 0 S-4;S b3 IS 19I ’ aaCC _1( 0C GipSO .)~3F ~~ I..~. JBJECT DAM SAFSTY

  13. National Dam Inspection Program. Star Junction Number 1 Dam (NDI Number PA-00198, PennDER Number 26-30) Ohio River Basin, Washington Run, Fayette County, Pennsylvania. Phase I Inspection Report,


    end and erosion K of the training dike has occurred. g. Instrumentation : No instrumentation was observed during the inspection. h. Downstream...DATE: 19 MAR 80 RN TDZ: 10.30.40 NATIONAL PROGR FOR TEM INSPEC ION OF NON-FEERAL DM HXDROLOMC AND MRAILIC ANALISIS OF STAR JUNCTION NamR 1 DAm PROBABLE

  14. National Dam Safety Inspection. D and R Pipeline Construction Company Lake (MO 20396), Osage - Gasconade Basin, Greene County, Missouri. Phase I Inspection Report.


    school, laboratory, etc., of the author. List city, state, and ZIP Code. d Block Prgram Element, Project, Task Area, and Work Unit Numbers. Enter here...Phase I Inspection Report This report presents the results of field inspection and evaluation of the D & R Pipeline Construction Company Lake Dam: It was...dwellings. our inspection and evaluation indicates that the com- bined spillways do not meet the criteria set forth in the guidelines for a dam having

  15. National Dam Safety Program. Conewango Creek Dam (Site 16A), (Inventory Number N.Y. 557), Allegheny River Basin, Conewango Creek Watershed, Cattaraugus County, New York. Phase I Inspection Report


    Classification ofThe hazard potential classification for this dam is HIGH because stream in the event of dam failure . Section 5 of this report presents more...AIpI 0 -t On:~ Wh i:- 30 3T’ OF~ <.% ~ ~ 5v coIO jrIc# r ’I, If~O t Plo . Qo Pin (’" CC’ . - ItVI q,~cuo cr o t. it., I plO$ tq I *l c .a 0n...LSECTIONAtAA SEC TION C C SOIL CONSERVATIO10N SFR \\"ICE ERVOýKIR DRAININ (LLEHr1 B-2 w. AI "IL .. / ..6’- -• ×IG- O ’ -. _ _ .._-_ ’ -M 1 -’ - .- IS I

  16. National Program of Inspection of Non-Federal Dams, Tennessee. Lambert Dam (Inventory Number TN 00901), Little Tennessee River Basin, near Six Mile, Blount County, Tennessee. Phase I Investigation Report,


    of Engineers Troy Wedekind Water Resjurces Engineer Tennessee Department of Conservarion Division of Water Resources SECTION 2 - PROJECT DESCRIPTION...Engineers Tom Porter Hydraulic Engineer Corps of Engineers Troy Wedekind Water Resources State o’ Tennessee Engineer 2. Lambert Dam is owned by Keith...drain pipe was covered during the initial part of the inspection, but was later uncovered by Troy Wedekind . Only a trickle of water was flowing through

  17. National Dam Inspection Report. Lake Ondawa Dam (NDI ID Number PA-517 DER ID Number 8-28) Susquehanna River Basin, Tributary Bentley Creek, Bradford County, Pennsylvania. Phase I Inspection Report,


    i " ’ i - - ~ ~, ,, -’ NU !|I ’ hs nI(I’ C;i o dd R / ,\\I C II " I . . . ../ 4P ’dN DAM SUAR REE DA AN LAE DAWA DA Ds , A". ’’ E ’ -i A~ F ,,, vat.. 1, P Codd,,4 014, 14, "I, C Tw 1- 04,shot *./A -e Ds I

  18. Excess Cancer Risk Assessment from Some Common X-Ray Examinations in Sabzevar County

    Mohammad Taghi Bahreyni Toossi


    Full Text Available Introduction: Nowadays ionizing radiation has a considerable contribution in medical diagnostic and treatment. Using ionizing radiation is increasing rapidly, so biological effects of ionizing radiation should be considered more. X-rays in the range of diagnostic radiology have hazardous effects and risks that are defined as random effects. These effects obey the LNT hypothesis that occur at low doses and include many types of cancer and genetic mutations. So it is very important to assess the risk of exposure in medical examinations. Cancer is one of these hazardous risks caused by low dose ionizing radiation that may occur during life after exposure. According to BEAR 7, low dose radiation is defined as radiation that produces doses near zero up to 100 mSv. Materials and Methods: This work was carried out in eight radiology centers in the Sabzevar county of Iran for 485 patients in eight typical x-ray examinations chosen for the study: chest PA, chest AP, lumbar spine AP, lumbar spine LAT, pelvis AP, abdomen AP, skull AP and Lat. In order to estimate the excess cancer risk, we need to obtain collective effective dose caused by radiation in the study population. Usually effective dose offers precise assessment of radiography examination injuries in adult patients. In this study, we used the PCXMC Monte Carlo based software to obtain effective dose and organ dose. This software calculates organ and effective dose following input of patient and radiographic conditions. Results: Average patient weight and height, entrance surface dose, parameters used for each type of examination, and DAP values were entered. Effective dose, collective effective dose, number of radiographs per year and the excess cancer risk arising from these radiographic examinations were then calculated.  Discussion and Conclusion: Excess risk of fatal cancer due to x-ray examinations in the study population was calculated by collective effective dose. This risk in the

  19. Allegheny County Hydrology Areas

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Hydrology Feature Dataset contains photogrammetrically compiled water drainage features and structures including rivers, streams, drainage canals, locks, dams,...

  20. Allegheny County Hydrology Lines

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Hydrology Feature Dataset contains photogrammetrically compiled water drainage features and structures including rivers, streams, drainage canals, locks, dams,...

  1. Allegheny County Hydrology Areas

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Hydrology Feature Dataset contains photogrammetrically compiled water drainage features and structures including rivers, streams, drainage canals, locks, dams,...

  2. Allegheny County Hydrology Lines

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Hydrology Feature Dataset contains photogrammetrically compiled water drainage features and structures including rivers, streams, drainage canals, locks, dams,...

  3. Dam Safety Concepts

    Duricic, J.


    The majority of dams constructed in the world are dams that can be categorized as embankment dams. Throughout history we can point to many failures of dams, and embankment dams in particular. Nowadays it is clear that the goal to construct stable dams has not been achieved, even with advanced techno

  4. Dam Safety Concepts

    Duricic, J.


    The majority of dams constructed in the world are dams that can be categorized as embankment dams. Throughout history we can point to many failures of dams, and embankment dams in particular. Nowadays it is clear that the goal to construct stable dams has not been achieved, even with advanced

  5. Dam Safety Concepts

    Duricic, J.


    The majority of dams constructed in the world are dams that can be categorized as embankment dams. Throughout history we can point to many failures of dams, and embankment dams in particular. Nowadays it is clear that the goal to construct stable dams has not been achieved, even with advanced techno

  6. National Dam Inspection Program. Fuller’s Lake Dam (NDI Number PA 00073 PennDER Number 58-121) Susquehanna River Basin. Salt Lick Creek Susquehanna County, Commonwealth of Pennsylvania. Phase I Inspection Report,


    Area ( square miles) - 0.95 b. Discharge at Dam Site (c.f.s.) Maximum Flood - 225 Spillway Capacity - (at Pool El. 1539.6 ft. M.S.L.) - 370 c. Elevation...PM: PPAINAGE AREA 1kNO CE~tp7Oic MAP 0 2000 4i000 6000 S~CALE I 2000, MI] CHi AFL B-AKER, JR.. INC. Subjec, z F-S, ’. /,,r S.O. -. V-7;- 7 THE AKER...NIICIIAVI, BAK~ER, JR., INC. Subie c’ T 4 S 4,6 ~ ’ S.O. No._______ [HE BAKERI ENGINEERS /6- - - Sheet No.~ of 1 Ito\\ 280 4:5 z r - (C...r. )Dro~ing No

  7. National Dam Inspection Program. Hathaway Pond Dam (NDI ID Number PA 00050, PennDER Number 58-06), Susquehanna River Basin, West Branch of Lackawanna River, Susquehanna County, Pennsylvania. Phase I Inspection Report


    34 ’" ’ , :J.. SECTION 3 - VISUAL INSPECTION 3.1 FINDINGS a. General - The dam was found to be in poor overall condition at the time of inspection on...outlet to basin divide. L = Length of water course from outlet to point opposite the centroid of drainage area. ca 1P MIC. AEI. BAKER, JR., INC. Subject...Pr.0 5V1A~ps- -s-zey -] V7 (/f.a 4 27. 4 tP.4,/)-7.4 o)) V= -z- 3 ~-/ A𔄃ZF f’- tje � 5V? 17,tt 7W,9 LV V10,xI: 0.30 -. . 7-,e r 4 7 ’i gesw’./7’ LV

  8. Final Independent External Peer Review Report Supplemental Major Rehabilitation Evaluation Report for Center Hill Dam, Caney Fork River, DeKalb County, Tennessee


    project manager and senior engineer for the Bee Tree Dam Spillway Capacity Expansion Project, North Carolina and the evaluation of air ramp alternatives...interests. She earned her M.S. in biology/ ecology in 1978 from Steven F. Austin State University and has received additional academic training in the NEPA... corridors , and power plants and other types of projects involving federal funding. Ms. Crouch has demonstrated experience with cultural surveys

  9. National Dam Safety Program. Fredonia Reservoir (Inventory Number NY-749), Lake Erie Basin. Chautauqua County, New York. Phase I Inspection Report,


    o of the dam revealed conditions which if not corrected constitute a a hazard to human life or pronerty ... .- ..... * ’ DD , 1473 CDITION OF INOV 2) Bench, place and compact any erbankment slips or slouchs 3) Place and compact embankment type material along allI eroded embankment...compact embankment type material adjacent to the spillway crest where the level of existing gradesis below the top of the retaining wall (see as

  10. Dam-Site Selection of Huayuan Reservoir Hydraulic Engineering Complex in Longjiang County%花园水库枢纽工程坝址选择



    In accordance with Planning for 100 Billion jin Grain Production Capability Construction in Heilongjiang Province compiled in 2008,Comprehensive Planning of Songhua River Watershed compiled in April,2010,Brief Introduction of Important Projects in Heilongjiang Province Water Conservancy Development "Twelve Five-year Plans" Planning compiled in July,2010 and Planning for Construction of 10 Million mu Paddy Fields Added Newly in Heilongjiang Province compiled in 2010,the Huayuan Reservoir was recommended as the important hydraulic engineering complex in the comprehensive regulation of Yalu River watershed in the near term.The total storage of Huayuan Reservoir is 0.372 billion m3 and irrigation area is 0.1313 million hm2.The curves of cost and submerge loss were used to estimate the project costs and investment for submerge compensation for the two dam sites located on the river section in light of the same task of flood control and irrigation.The cost of upper dam site is 311.23million Yuan more than the lower dam site,meanwhile,there exists the problems of partial submerged lands in Inner Mongolia,it is difficult to cooperate the submerge compensation problems over the different provinces,and the lower dam site will be selected at the stage of project proposal.%根据2008年编制的《黑龙江省千亿斤粮食生产能力建设规划》、2010年4月编制的《松花江流域综合规划》、2010年7月编制的《黑龙江省水利发展"十二五"规划重点工程项目简介》以及2010年编制的《黑龙江省新增1000万亩水田建设规划》,花园水库均被推荐为近期雅鲁河流域综合治理的重点枢纽工程。花园水库总库容3.72亿m3,灌溉面积13.13万hm2,在河段内两坝址按相同的防洪、灌溉任务,按造价曲线和淹没损失曲线估算工程造价和淹没补偿投资,上坝址比下坝址多31123万元,且存在淹没内蒙部分土地的问题,跨省区协调淹没赔偿问题难度大,项目建议书阶段选定下坝址。

  11. National Register Testing at 23BE1007, 23BE1008, and 23BE1010, Downstream from the Harry S. Truman Dam and Reservoir, Benton County, Missouri.


    geologic section of alluvial terraces of the Pomme de Terre River ........... 9 Figure 5. Downstream Truman project area and Benton County in relation...portion of the Truman Reservoir that is within the Ozark Highland Region (Salem Plateau) is restricted to the vicinity of the Pomme de Terre River and...and Holocene alluvial terraces that have been mapped in detail in the Breshear’s Bottoms area of the Pomme de Terre River (Haynes 1976, 1977, 1981

  12. Geochemical and γ ray characterization of Pennsylvanian black shales: Implications for elevated home radon levels in Vanderburgh County, Indiana.

    Scheller, Kent W; Elliott, William S


    Radon ((222)Rn) is a radioactive gas that results from the decay of uranium ((238)U) in the Earth's crust. This study characterizes the presence and relative quantity of radon precursors in the Pennsylvanian black shales of southwest Indiana. Cores were drilled on the campus of the University of Southern Indiana to a depth of 237.7 m (780 ft) during exploration for coal-bed methane. Gamma ray logs were taken to measure radioactive activity as a function of depth in the bore hole. Activity readings of 270, 467, 555, and 388 GAPI (American Petroleum Institute γ ray units) were measured at depths of 124.3 m (408 ft), 154.0 m (505 ft), 187.1 m (614 ft) and 214.0 m (702 ft) in four separate shale layers of the Pennsylvanian stratigraphic column. GAPI units are used in the petroleum industry when drilling to represent the relative intensities of γ radiation from (40)K, (232)Th, and (238)U in bore holes (Belknap et al., 1959). For purposes of this study, the high activity readings on the gamma ray logs were used only to identify at which depths further gamma ray spectroscopy of the cores would be completed in the laboratory. Gamma ray spectroscopic studies of these cores were conducted with a large volume NaI crystal detector to observe γ rays of specific energies. Characteristic γ rays from various isotopes were identified confirming the presence and relative quantity of radon precursors in core samples. Geochemical analysis of cores was also conducted to measure presence and quantity of trace metals and radon precursors. Of 744 homes tested in Vanderburgh County from 2007 to 2013, 169 homes (22.7 percent) had elevated radon levels greater than 148 mBq L(-1) (4.0 pCi L(-1)). Additionally, 246 homes (33.1 percent) had measured radon levels of 74-145 mBq L(-1) (2.0-3.9 pCi L(-1)). About 80 percent of elevated radon levels greater than 148 mBq L(-1) (4.0 pCi L(-1)) are located in proximity to depositional contacts between the Dugger and Shelburn formations, or the

  13. Cosmic-ray exposure history of the Norton County enstatite achondrite

    Herzog, G. F.; Albrecht, Achim; Ma, Peixue; Fink, David; Klein, Jeffrey; Middleton, Roy; Bogard, Donald D.; Nyquist, L. E.; Shih, C.-Y.; Garrison, D. H.; Reese, Young; Masarik, J.; Reedy, R. C.; Rugel, G.; Faestermann, T.; Korschinek, G.


    Abstract- We report measurements of cosmogenic nuclides in up to 11 bulk samples from various depths in Norton County. The activities of 36Cl, 41Ca, 26Al, and 10Be were measured by accelerator mass spectrometry; the concentrations of the stable isotopes of He, Ne, Ar, and Sm were measured by electron and thermal ionization mass spectrometry, respectively. Production rates for the nuclides were modeled using the LAHET and the Monte Carlo N-Particle codes. Assuming a one-stage irradiation of a meteoroid with a pre-atmospheric radius of approximately 50 cm, the model satisfactorily reproduces the depth profiles of 10Be, 26Al, and 53Mn (Norton County at a depth of 88 cm in a large body for 140 Ma prior to its liberation as a meteoroid with a radius of 50 cm and further CRE for 100 Ma.

  14. Aerial Magnetic, Electromagnetic, and Gamma-ray Survey, Berrien County, Michigan

    Duval, Joseph S.; Pierce, Herbert A.; Daniels, David L.; Mars, John L.; Webring, Michael W.; Hildenbrand, Thomas G.


    This publication includes maps, grids, and flightline databases of a detailed aerial survey and maps and grids of satellite data in Berrien County, Michigan. The purpose of the survey was to map aquifers in glacial terrains. This was accomplished by using a DIGHEMVRES mufti-coil, mufti-frequency electromagnetic system supplemented by a high sensitivity cesium magnetometer and 256-channel spectrometer. The information from these sensors was processed to produce maps, which display the conductive, magnetic and radioactive properties of the survey area. A GPS electronic navigation system ensured accurate positioning of the geophysical data. This report also includes data from the advanced spaceborne thermal emission and reflection (ASTER) radiometer. ASTER measures thermal emission and reflection data for 14 bands of the spectrum.

  15. Alpine dams

    Alain Marnezy


    Full Text Available Les barrages-réservoirs de montagne ont été réalisés initialement dans les Alpes pour répondre à la demande d’énergie en période hivernale. Une certaine diversification des usages de l’eau s’est ensuite progressivement développée, en relation avec le développement touristique des collectivités locales. Aujourd’hui, la participation des ouvrages d’Électricité De France à la production de neige de culture représente une nouvelle étape. Dans les régions où les aménagements hydroélectriques sont nombreux, les besoins en eau pour la production de neige peuvent être résolus par prélèvements à partir des adductions EDF. Les gestionnaires de stations échappent ainsi aux inconvénients liés à la construction et à la gestion des « retenues collinaires ». Cette évolution, qui concerne déjà quelques régions alpines comme la haute Maurienne ou le Beaufortin, apparaît comme une forme renouvelée d’intégration territoriale de la ressource en eau.Mountain reservoirs were initially built in the Alps to meet energy needs in the winter. A certain diversification in the uses of water then gradually developed, related to tourism development in the local communities. Today, the use of facilities belonging to EDF (French Electricity Authority to provide water for winter resorts to make artificial snow represents a new phase. By taking water from EDF resources to supply snow-making equipment, resort managers are thus able to avoid the problems related to the construction and management of small headwater dams. This new orientation in the use of mountain water resources already affects a number of alpine regions such as the Upper Maurienne valley and Beaufortain massif and represents a renewed form of the territorial integration of water resources.

  16. Distributional Impacts of Large Dams in China

    Bao, X.


    Dams on a river are believed to have heterogeneous impacts to the upstream, local and downstream areas. Generally, irrigation dams will bring benefits to the downstream by facilitating more irrigation, while it will bring negative impacts to upstream due to inundation or no impact to local area as a combination result of population dislocation and economic benefits. This paper checked the impacts of large dams (above 100 meters) on the upstream, downstream and local area, using 2000-2008 county level data in China. Robust heterogeneous impacts of different categories of dams (mainly dams serving for irrigation, hydropower, or other purposes) were found on different areas, using IV regression approaches. Dams higher than 100 meters are significantly and heterogeneously impacting agricultural production, urban employment and rural per capita income. Its beneficial impact on agriculture production is significant for downstream especially in continuous drought years. But its impacts on social welfare indicators, such as primary school enrollment and hospital beds, are not heterogeneously different across regions.

  17. Iran funds dam completion


    Iran has signed a contract with unnamed foreign financiers for US$300M to fund two half-finished dam schemes, according to Tehran radio. The schemes are the Ostur dam in Mianeh in East Azerbaijan province and the Molla Sadra dam in Fars province. The Ostur dam will have a storage capacity of 2B m3 and a 160 MW hydro power station.

  18. 78 FR 43868 - Notice of Intent To Prepare a Draft Environmental Impact Statement for the Whittier Narrows Dam...


    ... Statement for the Whittier Narrows Dam Safety Modification Study Report AGENCY: Department of the Army, U.S... Environmental Impact Statement (EIS) for the Whittier Narrows Dam Safety Modification Study (DSMS). Whittier Narrows Dam is located approximately 12 miles east of downtown Los Angeles, Los Angeles County, CA....

  19. Hoover Dam Learning Packet.

    Bureau of Reclamation (Dept. of Interior), Washington, DC.

    This learning packet provides background information about Hoover Dam (Nevada) and the surrounding area. Since the dam was built at the height of the Depression in 1931, people came from all over the country to work on it. Because of Hoover Dam, the Colorado River was controlled for the first time in history and farmers in Nevada, California, and…

  20. Surface gamma-ray survey of the Barre West quadrangle, Washington and Orange Counties, Vermont

    Walsh, Gregory J.; Satkoski, Aaron M.


    This study was designed to determine the levels of naturally occurring radioactivity in bedrock from surface measurements at outcrops during the course of 1:24,000-scale geologic mapping and to determine which rock types were potential sources of radionuclides. Elevated levels of total alpha particle radiation (gross alpha) occur in a public water system in Montpelier, Vermont. Measured gross alpha levels in the Murray Hill water system (Vermont Dept. of Environmental Conservation, unpub. data, 2005) have exceeded the maximum contaminant level of 15 picocuries per liter (pCi/l) set by the Environmental Protection Agency (EPA) (EPA, 2000). The Murray Hill system began treatment for radium in 1999. Although this treatment was successful, annual monitoring for gross alpha, radium, and uranium continues as required (Jon Kim, written communication, 2005). The water system utilizes a drilled bedrock well located in the Silurian-Devonian Waits River Formation. Kim (2002) summarized radioactivity data for Vermont, and aside from a statewide assessment of radon in public water systems (Manning and Ladue, 1986) and a single flight line from the National Uranium Resource Evaluation (NURE) (Texas Instruments, 1976) (fig. 1), no data are available to identify the potential sources of naturally occurring radioactivity in the local bedrock. Airborne gamma-ray surveys are typically used for large areas (Duval, 2001, 2002), and ground-based surveys are more commonly used for local site assessments. For example, ground-based surveys have been used for fault mapping (Iwata and others, 2001), soil mapping (Roberts and others, 2003), environmental assessments (Stromswold and Arthur, 1996), and mineral exploration (Jubeli and others, 1998). Duval (1980) summarized the methods and applications of gamma- ray spectrometry. In this study, we present the results from a ground-based gamma-ray survey of bedrock outcrops in the 7.5-minute Barre West quadrangle, Vermont. Other related and

  1. A Bird's-eye View with X-ray Vision: Remote-sensing tools to Monitor Reach-scale Response to Dam Removal on the Elwha River

    Ritchie, A. C.


    Repeat digital surface models, orthoimagery and sidescan sonar data are being generated to monitor river response to the largest dam removal and controlled sediment release in history on the Elwha River, on the Olympic Peninsula in Washington State. These products are generated using low-cost readily-available tools to collect data at a spatial and temporal scale that provides important insight into effects of base-level change, sediment release, and discrete hydrologic events on erosion of reservoir sediments, downstream sediment transport, and channel evolution above and below the dam sites. In combination, these products provide a view above and below the water surface to changes in sediment composition and morphology that other methods cannot capture at this spatial scale and both spatial and temporal resolution. Orthoimagery is developed from still images collected with a plane-mounted point-and-shoot camera using customized firmware from the open-source Canon Hack Development Kit (CHDK) with a total hardware cost of about $300 USD. Images are processed using structure-from-motion algorithms. Several software options are available. Sonar data are collected from a raft-mounted platform using a high-resolution 990 KHz Starfish sidescan sonar, with a water-resistant topside enclosure holding top-side electronics. A steerable pole-mount was developed for this application to allow the sidescan to to remain oriented in the direction of motion-over-ground.; Surface reconstruction from aerial images collected during Elwha dam removal project. ; bedforms near Elwha Sediment Treatment Plant from sediment released from Lake Aldwell, surveyed 12 July 2012.

  2. Dam removal: Listening in

    Foley, Melissa M.; Bellmore, James; O'Connor, James E.; Duda, Jeff; East, Amy E.; Grant, Gordon G.; Anderson, Chauncey; Bountry, Jennifer A.; Collins, Mathias J.; Connolly, Patrick J.; Craig, Laura S.; Evans, James E.; Greene, Samantha; Magilligan, Francis J.; Magirl, Christopher S.; Major, Jon J.; Pess, George R.; Randle, Timothy J.; Shafroth, Patrick B.; Torgersen, Christian; Tullos, Desiree D.; Wilcox, Andrew C.


    Dam removal is widely used as an approach for river restoration in the United States. The increase in dam removals—particularly large dams—and associated dam-removal studies over the last few decades motivated a working group at the USGS John Wesley Powell Center for Analysis and Synthesis to review and synthesize available studies of dam removals and their findings. Based on dam removals thus far, some general conclusions have emerged: (1) physical responses are typically fast, with the rate of sediment erosion largely dependent on sediment characteristics and dam-removal strategy; (2) ecological responses to dam removal differ among the affected upstream, downstream, and reservoir reaches; (3) dam removal tends to quickly reestablish connectivity, restoring the movement of material and organisms between upstream and downstream river reaches; (4) geographic context, river history, and land use significantly influence river restoration trajectories and recovery potential because they control broader physical and ecological processes and conditions; and (5) quantitative modeling capability is improving, particularly for physical and broad-scale ecological effects, and gives managers information needed to understand and predict long-term effects of dam removal on riverine ecosystems. Although these studies collectively enhance our understanding of how riverine ecosystems respond to dam removal, knowledge gaps remain because most studies have been short (methods in the U.S.

  3. Dam to the Rescue


    The Three Gorges Dam relieves the summer drought in south and central China,but may contribute to other problems The Three Gorges Dam played an important role in relieving China’s drought in central and eastern prov-inces that had been using increased water discharges from the Dam to irrigate dry farmlands facing the worst drought int he last 60 years in 2011.

  4. Living with dams

    H.L.F. Saeijs (Henk); K.D. Schuijt (Kirsten)


    textabstractDams have proven their usefulness in preventing and mitigating floods, and water scarcity and generating electricity. They are indispensable in present society. But at the same time, they cause serious ecological, social and economical problems. Consequently we have to live with a dams

  5. Benefit Analysis and Economic Evaluation of the Strengthening and Maintenance Work of Weak,Dangerous and Silted Dams in Xiji County%西吉县病险淤地坝加固维修工程效益分析及经济评价



    Through strengthening and maintenance of weak, dangerous and silted dams in Xiji County, relatively complete small watershed bam systems are formed. The flood control security standard and flood control capability are improved, and soil and water erosion is effectively controlled. At the same time, transportation, drinking water and irrigation problems are also relieved.%通过西吉县病险淤地坝加固维修,形成各小流域较为完善的坝系工程,提高了淤地坝的防洪保收标准及防洪能力,有效的防治了水土流失,同时也对区域内的交通、饮水、灌溉问题进行了有效的缓解。

  6. Dams: Pros and Cons


    The Dam was built for the main purpose of water supply to university community. Data on .... The decision on who is to participate in a full EIA on a water ... METHOD AND MATERIALS ..... Development”, Encyclopedia of Life Support Systems,.

  7. County Spending

    Montgomery County of Maryland — This dataset includes County spending data for Montgomery County government. It does not include agency spending. Data considered sensitive or confidential and will...

  8. Analysing and Selecting the Schemes of Removing Danger and Consolidating Dam for Bosigan Reservoir in Pishan County of XinJiang Uygur Autonomous Region%新疆皮山县波斯干水库除险加固坝体方案的分析与确定



    The Bosigan Reservoir is located in Pishan County of Hetian Prefecture in XinJiang Uygur Autonomous Region.This reservoir was constructed in the 1970's.Its total reservoir capacity is 3×106 m3,the initial design beneficial capacity is 1.5×106 m3.But the present silted capacity has reached 1.288×106 m3,and the remainder capacity only 0.2117×106 m3.So this reservoir needs very much removing danger and consolidating.In the paper,the selection of capacity-restoring mode between dam-heightening scheme and reservoir sediment removal scheme,and the selection of seepage control mode between vertical seepage control scheme and upstream dam slope seepage control scheme are expounded in many aspects.At last,the reasonable schemes are selected,and the reservoir's normal functions on flood control and irrigation can be restored,and reach satisfying use effect.%波斯干水库位于新疆和田地区皮山县境内,工程建于上世纪70年代,总库容300万m3,兴利库容150万m3,现已淤积128.83万m3,剩余库容21.17万m3,迫切需要进行除险加固。文中从是对坝体加高还是对水库清淤、对坝体是进行垂直防渗还是对边坡防渗等经过多方面比选,最终确定合理的除险加固方式,恢复其正常的防洪和灌溉功能,以达到满意的工程使用效果。

  9. Dam safety in British Columbia

    Hunt, H.M.; Round, R.P.D.


    Many dams in British Columbia were built before 1900, and a comprehensive inspection and surveillance program has been developed. The background and implementation of this program are described. Topics discussed include program responsibilities, classification of dams, organization, the dam safety program, and coordination with other agencies. (PMA)

  10. A preliminary study of the failure mechanisms of cascading landslide dams

    Gordon GD Zhou; Peng Cui; Xinghua Zhu; Jinbo Tang; Huayong Chen; Qicheng Sun


    abstract Landslide dams commonly form when mass earth or rock movements reach a river channel and cause a complete or partial blockage of the channel. Intense rainfalls can induce upstream flows along a sloping channel that significantly affect downstream landslide dams. If a series of landslide dams are collapsed by incoming mountain torrents (induced by intense rainfall), large debris flows can form in a very short period. Furthermore, the failure of these dams can amplify the magnitude and scale of debris flows in the flow direction. The catastrophic debris flows that occurred in Zhouqu County, China on 8 August 2010 were caused by intense rainfall and the upstream cascading failure of landslide dams along the gullies. Incorporating the role of outburst floods associated with the complete or partial failure of landslide dams is an interesting problem usually beyond the scope of analysis because of the inherent modeling complexity. To understand the cascading failure modes of a series of landslide dams, and the dynamic effect these failures have on the enlargement of debris flow scales, experimental tests are conducted in sloping channels mimicking field conditions, with the modeled landslide dams distributed along a sloping channel and crushed by different upstream flows. The failure modes of three different cascades of landslide dams fully or partially blocking a channel river are parametrically studied. This study illustrates that upstream flows can induce a cascading failure of the landslide dams along a channel. Overtopping is the primary failure mechanism, while piping and erosion can also induce failures for different constructed landslide dams. A cascading failure of landslide dams causes a gradually increasing flow velocity and discharge of the front flow, resulting in an increase in both diameter and percentage of the entrained coarse particles. Furthermore, large landslide blockages can act to enhance the efficiency of river incision, or conversely to

  11. Gene Wash and Copper Basin Dams are surviving alkali-aggregate reaction

    Hill, C.J.


    Gene Wash and Copper Basin Dams were constructed in 1937 and 1938, and are owned and operated by the Metropolitan Water District of Southern California (MWD). The dams are located in San Bernardino County, California, close to the Colorado River, and very close to the easternmost point of California. They form two intermediate storage facilities on the Colorado River Aqueduct system which conveys water from Lake Havasu to the Los Angeles and San Diego areas. The locations of the dams are shown. Gene Wash Dam is a concrete arch structure, with a maximum height of arch of 131 feet. There is a gravity thrust block on the right abutment and the total crest length is 430 feet. Copper Basin Dam is a concrete arch dam with a maximum height of arch of 187 feet and a crest length of 253 feet. Plans, elevations and sections for both dams. The dams are in the Whipple Mountains at the eastern edge of the Mojave Desert. Between June and October, maximum temperatures usually exceed 100 degrees Farenheit, while daily low temperatures in this period are generally in the 60`s and 70`s. Winter temperatures are mild, with daytime highs in the 70`s and 80`s, and lows only occasionally below freezing. The area is arid, with total annual rainfall generally between two and ten inches. Both dams were built in desert washes with no permanent flow. The foundation for both structures is a strong, erosion-resistant, red-brown, non-marine sandstone and conglomerate of Tertiary age known as the Copper Basin Formation (Buwalda, 1937). Spillways for both dams are ungated ogee crests, which are separate from the dams. Gene Wash Dam and Copper Basin Dam are geographically close together, are of similar design, and were constructed at the same time, using the same materials. Their performance since construction, not surprisingly, has been similar.

  12. In-situ gamma-ray site characterization of the Tatum Salt Dome Test Site in Lamar County, Mississippi

    Faller, S.H. (Environmental Protection Agency, Las Vegas, NV (United States))


    Field surveys of gamma-ray emitting nuclides and soil core sampling were conducted at 12 sites on the Tatum Salt Dome Test Site and surrounding control areas to determine exposure rates from surficial radioactivity. 137Cs was the only man-made radionuclide detected and was most abundant at three off-site locations on cultivated lawns. 137Cs inventories at all of the on-site survey locations were lower than expected, given the high annual precipitation in the area. The vertical distributions were more extended than those reported for undisturbed sites. Pressurized ion chamber measurements indicated no significant differences in exposure rates on and off the test site.

  13. USGS Dam Removal Science Database

    Bellmore, J. Ryan; Vittum, Katherine; Duda, Jeff J.; Greene, Samantha L.


    This database is the result of an extensive literature search aimed at identifying documents relevant to the emerging field of dam removal science. In total the database contains 179 citations that contain empirical monitoring information associated with 130 different dam removals across the United States and abroad. Data includes publications through 2014 and supplemented with the U.S. Army Corps of Engineers National Inventory of Dams database, U.S. Geological Survey National Water Information System and aerial photos to estimate locations when coordinates were not provided. Publications were located using the Web of Science, Google Scholar, and Clearinghouse for Dam Removal Information.

  14. Analysis of the ground-water flow system, geochemistry, and underseepage in the vicinity of the Red Rock Dam near Pella, Iowa

    Lucey, K.J.


    The U.S. Army Corps of Engineers operates the Red Rock Dam on the Des Moines River in Marion County, Iowa. The dam consists of a gravity concrete control structure between two earthen embankments and has an impoundment storage capacity of 1,700,000 acre-feet. Since the impoundment of Lake Red Rock commenced during 1969, water seepage beneath the dam has been significant enough to cause continuing investigation by the Corps of Engineers of its source and implications.

  15. Risk assessment for large Romanian dams situated on Bistrita and Siret Rivers

    Moldovan, Iren-Adelina; Petruta Constantin, Angela; Popescu, Emilia; Toma-Danila, Dragos; Otilia Placinta, Anica


    The work will present an ongoing national Project that have as final goal to provide the local emergency services with warnings of a potential dam failure and ensuing flood as a result of a large earthquake occurrence, allowing further public training for evacuation. Probabilistic seismic hazard (PSH), vulnerability and risk studies in 6 counties from Moldova region including Izvorul Muntelui Dam, down on Bistrita and following on Siret River and theirs affluent will be accomplished during the project. A number of 5 large dams (the most vulnerable) will be studied in detail and flooding maps will be drawn to find the most exposed downstream localities both for risk assessment studies and warnings. The results will consist in local and regional seismic information, dams specific characteristics and locations, seismic hazard maps and risk classes, for all dams sites (for more than 30 dams), inundation maps (for the most vulnerable 5 dams from the region) and possible affected localities. The maps will provide the best available estimate of the general location and extent of dam failure inundation areas and will tell if a specific location lies within a dam failure inundation zone. Besides periodical technical inspections, the monitoring and the surveillance of dams' related structures and infrastructures, there are some more seismic specific requirements towards dams' safety. The most important one is the seismic risk assessment that can be accomplished by rating the dams into seismic risk classes using the theory of Bureau and Ballentine (2002), and Bureau (2003), taking into account the maximum expected peak ground motions at the dams site. In this paper we will obtain the ground motion parameters in the dams locations using probabilistic hazard assessment techniques, the structures vulnerability and the downstream risk characteristics (human, economical, historic and cultural heritage, etc) in the areas that might be flooded in the case of a dam failure, and will

  16. The dam design of Three Gorges Project

    Wang Xiaomao; Xu Linxiang; Liao Renqiang


    The dam of Three Gorges Project is a concrete gravity dam with the crest elevation of 185 m, the maximum height of 181 m and dam axis length of 2 309.5 m. The dam consists of spillway, powerhouse, non-over flow, ship-lift, temporary ship-lock, left diversion wall and longitudinal cofferdam blocks. Some key techniques relating to dam structure design are presented, including hydraulics of flood discharge structure, dam joint design, layout and structural type of penstock, deep anti-sliding stability of dam foundation, reconstruction of temporary ship-lock and closed drainage and pumping of dam foundation.

  17. Tarbela Dam Project

    Khan, B.A. [WAPDA Tarbela Dam Project (Pakistan); Ahmad, W. [Siemens Pakistan Ltd., Islamabad (Pakistan)


    Construction of one of the world's largest water resource development project is discussed. The Tarbela project is built on the Indus River, (itself one of the largest rivers of the world) and consists of a 9,000 feet long and 465 feet high earth and rockfill embankment across the entire width of the river with two spillways cutting through the left bank. On the left bank valley there are two auxiliary embankment dams to close the gap. A total of five tunnels, each a mile long, have been constructed for irrigation releases and power generation. Electricity is being generated by two power generating plants constructed on three of these tunnels. They have a generating capacity of 3,478 MW, supplying 40 per cent of all Pakistani demand. Several 'firsts' are identified. For example, the dam is the world's largest, containing over 200 million cubic yards of earth and rock, as are the five tunnels (14 meters in diameter), as well as the outlet gates. The energy release by the water gushing through the five tunnels at maximum level is more than 13 million KW, approximately equivalent to 10 million horsepower. 1 ref.

  18. Determination of Seepage and Analysis of Earth Dams (Case Study: Karkheh Dam)

    A. Kamanbedast; M. Shahosseini


    Because of the increasing trend of building dam throughout Iran; it is necessary to optimize dam buildings and operations. Dam or Hydropower industry has two types of buildings; normally: (1) Concrete dams (2) Embankment (earth) dams. Generally, scientists and engineers use different methods to enhance safety and decrease any errors in calculation due to maintenance of water storage especially hydro structure of the dam. It is necessary to investigate the dam seepage control; commonly use...

  19. Landscape Evolution Modelling of naturally dammed rivers

    Gorp, van W.; Temme, A.J.A.M.; Baartman, J.E.M.; Schoorl, J.M.


    Natural damming of upland river systems, such as landslide or lava damming, occurs worldwide. Many dams fail shortly after their creation, while other dams are long-lived and therefore have a long-term impact on fluvial and landscape evolution. This long-term impact is still poorly understood and

  20. Landscape Evolution Modelling of naturally dammed rivers

    van Gorp, Wouter; Temme, Arnaud J. A. M.; Baartman, Jantiene E. M.; Schoorl, Jeroen M.


    Natural damming of upland river systems, such as landslide or lava damming, occurs worldwide. Many dams fail shortly after their creation, while other dams are long-lived and therefore have a long-term impact on fluvial and landscape evolution. This long-term impact is still poorly understood and la

  1. 76 FR 12094 - Whitman River Dam, Inc.


    ... Federal Energy Regulatory Commission Whitman River Dam, Inc. Notice of Application Tendered for Filing.... Applicant: Whitman River Dam, Inc. e. Name of Project: Crocker Dam Hydro Project. f. Location: On the... analysis at this time. n. The Crocker Dam Hydro Project would consist of: (1) The existing...

  2. Detecting temporal change in land-surface altitude using robotic land-surveying techniques and geographic information system applications at an earthen dam site in Southern Westchester County, New York

    Noll, Michael L.; Chu, Anthony


    In 2005, the U.S. Geological Survey began a cooperative study with New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment at the Hillview Reservoir in southern Westchester County, New York. Monthly site inspections at the reservoir indicated an approximately 90-square-foot depression in the land surface directly upslope from a seep that has episodically flowed since 2007. In July 2008, the U.S. Geological Survey surveyed the topography of land surface in this depression area by collecting high-accuracy (resolution less than 1 inch) measurements. A point of origin was established for the topographic survey by using differentially corrected positional data collected by a global navigation satellite system. Eleven points were surveyed along the edge of the depression area and at arbitrary locations within the depression area by using robotic land-surveying techniques. The points were surveyed again in March 2012 to evaluate temporal changes in land-surface altitude. Survey measurements of the depression area indicated that the land-surface altitude at 8 of the 11 points decreased beyond the accepted measurement uncertainty during the 44 months from July 2008 to March 2012. Two additional control points were established at stable locations along Hillview Avenue, which runs parallel to the embankment. These points were measured during the July 2008 survey and measured again during the March 2012 survey to evaluate the relative accuracy of the altitude measurements. The relative horizontal and vertical (altitude) accuracies of the 11 topographic measurements collected in March 2012 were ±0.098 and ±0.060 feet (ft), respectively. Changes in topography at 8 of the 11 points ranged from 0.09 to 0.63 ft and topography remained constant, or within the measurement uncertainty, for 3 of the 11 points.Two cross sections were constructed through the depression area


    Costa, John E.; Schuster, Robert L.


    Of the numerous kinds of dams that form by natural processes, dams formed from landslides, glacial ice, and late-neoglacial moraines present the greatest threat to people and property. Landslide dams form a wide range of physiographic settings. The most common types of mass movements that form landslide dams are rock and debris avalanches; rock and soil slumps and slides; and mud, debris, and earth flows. The most common initiation mechanisms for dam-forming landslides are excessive rainfall and snowmelt and earthquakes. Natural dams may cause upstream flooding as the lake rises and downstream flooding as a result of failure of the dam. Although data are few, for the same potential energy at the dam site, downstream flood peaks from the failure of glacier-ice dams are smaller than those from landslide, moraine, and constructed earth-fill and rock-fill dam failures.

  4. Big Lake Dam Inspection Report

    US Fish and Wildlife Service, Department of the Interior — This report summarizes an inspection of the Big Lake Dam that was done in September of 1983. The inspection did not reveal any conditions that constitute and...


    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  6. Conflicts Associated with Dam Removal in Sweden

    Anna G. C. Lejon


    Full Text Available The increasing number of deteriorating old dams that need renovation or have lost their function make dam removal a viable management option. There are at least four major reasons for dam removal: safety, law and policy, economy, and ecology. Here we discuss 17 Swedish dams that were recently considered for removal. Because dam removal usually causes controversy, dam removal initiatives may succeed, fail, or result in a compromise such as a bypass channel for migrating fish. We identify and discuss three major obstructions to dam removal: funding, cultural-historical values, and threatened species. To facilitate dam removal, the reasons for, and the effects of, dam removal must be carefully explained, and the public and stakeholders must be kept informed. In complicated cases in which compromise solutions may be the most feasible outcome, the integration of the knowledge of different stakeholders is crucial. The involvement of diverse stakeholders increases their willingness to find compromises, thus avoiding conflicts and failures.

  7. Damming the rivers of the Amazon basin

    Latrubesse, Edgardo M.; Arima, Eugenio Y.; Dunne, Thomas; Park, Edward; Baker, Victor R.; D'Horta, Fernando M.; Wight, Charles; Wittmann, Florian; Zuanon, Jansen; Baker, Paul A.; Ribas, Camila C.; Norgaard, Richard B.; Filizola, Naziano; Ansar, Atif; Flyvbjerg, Bent; Stevaux, Jose C.


    More than a hundred hydropower dams have already been built in the Amazon basin and numerous proposals for further dam constructions are under consideration. The accumulated negative environmental effects of existing dams and proposed dams, if constructed, will trigger massive hydrophysical and biotic disturbances that will affect the Amazon basin’s floodplains, estuary and sediment plume. We introduce a Dam Environmental Vulnerability Index to quantify the current and potential impacts of dams in the basin. The scale of foreseeable environmental degradation indicates the need for collective action among nations and states to avoid cumulative, far-reaching impacts. We suggest institutional innovations to assess and avoid the likely impoverishment of Amazon rivers.

  8. Dam risk assistant analysis system design


    In order to reduce the labor intensity and task difficulty of dam risk analysis and to meet the actual requirement of dam risk analysis,it is necessary to establish a dam risk assistant analysis system.The program structure and the implementation ways of the dam risk assistant analysis system are analyzed,and a procedural framework with "three-tier and multi-database" structure and "level structure" is established.The concept of dam risk assessment system modular development is proposed and the coupled mode of function module and data is improved.Finally,the dam risk assistant analysis system is developed using Delphi visual programming language.

  9. Emergency Action Plan : Havana Street Dam : Adams County, Colorado

    US Fish and Wildlife Service, Department of the Interior — The purpose of this Emergency Action Plan (EAP) is to reduce the potential for loss of life and injury, and to minimize property damage during an unusual or...

  10. An Interpretive History of Coyote Dam Mendocino County, California,


    ING DIVISION r - O hIONS DIVISION PLANIN3IG D [~1 EREPORTS BRANCH BRANCH %’I NCO M E’ DA M4 + _ + -_ Normal and Emergency Reervoir Regla - tion...beginning of this volume. -69- GIBBS , George K. and SCHAFER, George M. 1939 Reconnaissance Survey for Preliminary Flood Control-Russian River Watershed

  11. Frankenmuth Dam Fish Passage, Cass River, Saginaw County, Michigan


    present. (d) Vegetated shallows – Not present. (e) Coral reefs – Not present. (f) Riffle and pool complexes – No significant adverse effect. (5...s due to a series of year class failures brought on by a combination of commercial over-fishing, pollution , and an influx of invasive species

  12. 75 FR 50777 - Minidoka Dam Spillway Replacement, Minidoka County, ID


    ... addition, the potential for ice damage to the stoplog piers requires that reservoir water levels be dropped... document those changes and/or impacts. DATES: Reclamation will not make a decision on the proposed action... headgates. If these failures occur, Reclamation may not be able to meet contractual obligations for...

  13. The Bandini-Cota Adobe, Prado Dam, Riverside County, California.


    in some variant of English common bond (Figure 10). In plan view, the drawing suggests alterna - ting patterns of two headers and one stretcher...N9); the glaze has a bluish tinge, also N9. I $b 57 L1 Mexican Lead Glazed Earthenware This ware is the loza corriente of contemporary usage, the

  14. VT High Risk Dam Inundation Areas

    Vermont Center for Geographic Information — (Link to Metadata) Preliminary release Storm-Day dam inundation areas digitized from various source Emergency Action Plans. These dams were prioritized for...

  15. Dams and Obstructions along Iowa's Canoe Routes

    Iowa State University GIS Support and Research Facility — This dataset represents obstruction to canoe and boat users of the canoe routes of Iowa. This may represent actual dams, rock dams (natural or man made), large...

  16. 78 FR 53494 - Dam Safety Modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams


    ... Dam Safety Modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams AGENCY: Tennessee... preferred alternative in its final environmental impact statement (EIS) for the dam safety modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams. The notice of availability (NOA) of the...

  17. National Dam Safety Program. Court Street Dam (Inventory Number NY 6843), Monroe County, New York


    PtAr , 6-hOUR 24-dOOk 72-doUR TOTAL, VOLUME CFS 299012. 21b47y. 235844. 120159. 1836321. C.46 4b7. v395. 678. 3403. b1999. Ifis 2.57 8.16 12.48 15.89 A...obbo o03. 5750. sib5. 5030. 471. 4358. 40bb. 3194. PtAr . 6-ti0LH 24-OUR 72-tiOU 101 L v0Lu’qi CES 213945. - 21u0-9. 1921o7. 12,222. 19535ub. C-6 tw5o...408. PtAR b-OUt 24-hOUR 72-flOOR XU1AL VOLUIE Crs 49b9d. 4958. 38477. 18396. 27b970. c i 14u7. 1404. 1090. 521. 79U0.1..Cn0S 1.80 5.59 8.02 10.14 4


    Avazbek Ishbaev


    Full Text Available The dams have very important roles to agricultural activities. Especially, West Java with 240,000 hectares of agricultural land, needs a good dam structure that can be used sustainably. Jatiluhur dam in Purwakarta, West Java is one of big dams in Indonesia which has important rules not only for Purwakarta but also for Jakarta, Karawang and Bekasi residents. A study and observation about safety and dam stability is needed to prevent any damage. The purpose of this research were to identify parameters that influenced dam safety and to evaluate dam reliability based on index tools. Analysis was done using risk index tools. The result showed that the condition of the dam of Jatiluhur is still satisfied with indicators, "Idam"-750. The total index risk was 127.22 and the safety factor was 83.04 out of 100. Therefore, Jatiluhur dam could be classified as safe and no need for particular treatments. Jatiluhur dam can be operated in normal condition or abnormal condition with periodic monitoring. Keywords: dam safety, evaluation, Jatiluhur Dam, risk index tools

  19. Webinar: Stepped chute design for embankment dams

    Changing demographics in the vicinity of dams have led to hazard creep in a number of dams worldwide. Many of these dams now have insufficient spillway capacity as a result of these changes in hazard classification from low to significant or high hazard. Stepped chutes applied to the embankment da...

  20. Dams life; La vie des barrages



    The paper reports on the conclusions of decennial and annual inspections of French dams. Dams surveillance is performed by the operators and consists in visual examinations and measurements. Concrete dams, in particular, always have more or less developed fissures with water sweating threw the concrete mass or the foundations. Old concrete often show low swelling phenomena which are measured too. (J.S.)

  1. The formation and failure of natural dams

    Costa, J.E.; Schuster, R.L.


    Of the numerous kinds of dams that form by natural processes, dams formed from landslides, glacial ice, and neoglacial moraines present the greatest threat to people and property. The most common types of mass movements that form landslide dams are rock and debris avalanches, rock and soil slumps and slides, and mud, debris, and earth flows. The most common initiation mechanisms for dam-forming landslides are excessive rainfall and snowmelt and earthquakes. Landslide dams can be classified into six categories based on their relation with the valley floor. Type I dams (11%) of the 81 landslide dams around the world that were classifed do not reach from one valley side to the other. Type II dams (44%) span the entire valley flood, occasionally depositing material high up on opposite valley sides. Type III dams (41%) move considerable distances both upstream and downstream from the landslide failure. Type IV dams (1%) are rare and involve the contemporaneous failure of material from both sides of a valley. Type V dams (1%) are also rare, and are created when a single landslide sends multiple tongues of debris into a valley forming two or more landslide dams in the same surfaces, that extend under the stream or valley and emerge on the opposite valley side. Many landslide dams fail shortly after formation. Overtopping is by far the most common cause of failure. Glacial ice dams can produce at least nine kinds of ice-dammed lakes. The most dangerous are lakes formed in main valleys dammed by tributary glaciers. Failure can occur by erosion of a drainage tunnel under or through the ice dam or by a channel over the ice dam. Cold polar ice dams generally drain supraglacially or marginally by downmelting of an outlet channel. Warmer temperate-ice dams tend to fail by sudden englacial or subglacial breaching and drainage. Late neoglacial moraine-dammed lakes are located in steep mountain areas affected by the advances and retreats of valley glaciers in the last several

  2. Research on shape optimization of CSG dams

    Xin CAI


    Full Text Available The multi-objective optimization method was used for shape optimization of cement sand and gravel (CSG dams in this study. The economic efficiency, the sensitivities of maximum horizontal displacement and maximum settlement of the dam to water level changes, the overall stability, and the overall strength security were taken into account during the optimization process. Three weight coefficient selection schemes were adopted to conduct shape optimization of a dam, and the case studies lead to the conclusion that both the upstream and downstream dam slope ratios for the optimal cross-section equal 1:0.7, which is consistent with the empirically observed range of 1:0.6 to 1:0.8 for the upstream and downstream dam slope ratios of CSG dams. Therefore, the present study is of certain reference value for designing CSG dams.

  3. Future directions of dam safety in Canada

    Verzeni, Gerard [Hydro Quebec, QC, (Canada)


    Gerard Verzeni, former director of the dam safety & environment at Hydro-Quebec introduced the future directions of dam safety in Canada. New and numerous challenges are emerging for the dam safety community. Measurable effects of climate changes illustrate that hydraulic forecasts would change drastically. Loads with times and amplitudes which are different from the actual knowledge will apply on dams. The development of new types of dams using recent technologies raises several issues, for example the longevity of such installations. The installations are becoming old and soon will require complete renovation and update for regulation and standards compliance. Concrete dams already need efforts and investment to maintain then in a safe state. Various factors will influence these challenges such as human resources in the dam safe community. In these conditions, it is important that organizations like CDA play an important role in providing support and reference and in being a driver for the whole industry.

  4. Study of Dam-break Due to Overtopping of Four Small Dams in the Czech Republic

    Zakaraya Alhasan


    Full Text Available Dam-break due to overtopping is one of the most common types of embankment dam failures. During the floods in August 2002 in the Czech Republic, several small dams collapsed due to overtopping. In this paper, an analysis of the dam break process at the Luh, Velký Bělčický, Melín, and Metelský dams breached during the 2002 flood is presented. Comprehensive identification and analysis of the dam shape, properties of dam material and failure scenarios were carried out after the flood event to assemble data for the calibration of a numerical dam break model. A simple one-dimensional mathematical model was proposed for use in dam breach simulation, and a computer code was compiled. The model was calibrated using the field data mentioned above. Comparison of the erodibility parameters gained from the model showed reasonable agreement with the results of other authors.

  5. Management of dams for the next Millennium: proceedings of the 1999 Canadian Dam Association



    The meeting featured seven sessions with 18 papers abstracted/indexed therein as follows: keynote address: tailings dams safety - implications for the dam safety community; 1 - design and performance: performance monitoring of dams: are we doing what we should be doing?; tailings dams from the perspective of conventional dam engineering; and design overview of Syncrude's Mildred Lake east toe berm; 2 - design and modelling: use of a 2D model for a dam break study on the ALCAN hydroelectric complex in Quebec; and spillway design implications resulting from changes in rainfall extremes; 3 - risk and dam safety I: closing the gaps in the dam safety guidelines; the reality of life safety consequence classification; and surveillance practices for the next millenium; 4 - risk and dam safety II: quantitative risk-assessment using the capacity-demand analysis; and new guidelines for dam safety classification; 5 - millenium issues: expectations of immortality, dam safety management into the next millenium; 6 - rehabilitation techniques: the unconventional application of conventional materials; nondestructive testing technology to characterize concrete dam/bedrock interface; method and instrument for detecting crack in concrete; and grouting of the cracks in the Arch 5-6 - Daniel Johnson Dam; and 7 - case studies: rehabilitation of an 80 year old Ambursen type dam; and debris booms for the protection of spillways.

  6. Brazil's Amazonian dams: Ecological and socioeconomic impacts

    Fearnside, P. M.


    Brazil's 2015-2024 Energy Expansion Plan calls for 11 hydroelectric dams with installed capacity ≥ 30 MW in the country's Amazon region. Dozens of other large dams are planned beyond this time horizon, and dams with consumers. Population displacement is a major impact; for example, the Marabá Dam would displace 40,000 people, mostly traditional riverside dwellers (ribeirinhos). Various dams impact indigenous peoples, such as the Xingu River dams (beginning with Belo Monte) and the São Luiz do Tapajós and Chacorão Dams on the Tapajós River. Brazil has many energy options other than dams. Much energy use has little benefit for the country, such as exporting aluminum. Electric showerheads use 5% of the country's power. Losses in transmission lines (20%) are far above global averages and can be expected to increase as Amazonian hydroelectric dams far from consumer centers come on line. Brazil has tremendous wind and solar potential, but these do not have the same priority as dams. At the root of many questionable policies is a decision-making process in need of reform.

  7. Exporting dams: China's hydropower industry goes global.

    McDonald, Kristen; Bosshard, Peter; Brewer, Nicole


    In line with China's "going out" strategy, China's dam industry has in recent years significantly expanded its involvement in overseas markets. The Chinese Export-Import Bank and other Chinese financial institutions, state-owned enterprises, and private firms are now involved in at least 93 major dam projects overseas. The Chinese government sees the new global role played by China's dam industry as a "win-win" situation for China and host countries involved. But evidence from project sites such as the Merowe Dam in Sudan demonstrates that these dams have unrecognized social and environmental costs for host communities. Chinese dam builders have yet to adopt internationally accepted social and environmental standards for large infrastructure development that can assure these costs are adequately taken into account. But the Chinese government is becoming increasingly aware of the challenge and the necessity of promoting environmentally and socially sound investments overseas.

  8. Dam safety review, classification of dams for the Novia Scotia Power Inc. Black River hydroelectric system

    Alderman, Aaron; Small, Andy [AMEC Earth and environmental, Fredericton, (Canada); O' Neil, Ellis [Nova Scotia Power Inc., Halifax, (Canada)


    In 2009, AMEC was retained by Nova Scotia Power Inc. (NSPI) to conduct a dam safety review of the dams that are part of the Black River Hydroelectric System. This paper presented the results of this dam classification exercise which was carried out for the Bear River hydroelectric system in Nova Scotia, based on the 2007 Canadian Dam Association (CDA) dam safety guidelines. Flood mapping and dam-break analysis were performed for events ranging from the 1:100 year to PMF flood events, including cascading events. These results were used to draw up a classification of the dams. Associated design criteria were then developed. Following the assessment of the dam sites, conclusions and recommendations were discussed. The recommendations were presented in terms of regular maintenance items and reconstruction items, which are now used by NSPI to determine the party responsible for undertaking the recommendation and for evaluation of the maintenance and reconstruction schedules.

  9. Measurement of Dam Deformations: Case Study of Obruk Dam (Turkey)

    Gulal, V. Engin; Alkan, R. Metin; Alkan, M. Nurullah; İlci, Veli; Ozulu, I. Murat; Tombus, F. Engin; Kose, Zafer; Aladogan, Kayhan; Sahin, Murat; Yavasoglu, Hakan; Oku, Guldane


    In the literature, there is information regarding the first deformation and displacement measurements in dams that were conducted in 1920s Switzerland. Todays, deformation measurements in the dams have gained very different functions with improvements in both measurement equipment and evaluation of measurements. Deformation measurements and analysis are among the main topics studied by scientists who take interest in the engineering measurement sciences. The Working group of Deformation Measurements and Analysis, which was established under the International Federation of Surveyors (FIG), carries out its studies and activities with regard to this subject. At the end of the 1970s, the subject of the determination of fixed points in the deformation monitoring network was one of the main subjects extensively studied. Many theories arose from this inquiry, as different institutes came to differing conclusions. In 1978, a special commission with representatives of universities has been established within the FIG 6.1 working group; this commission worked on the issue of determining a general approach to geometric deformation analysis. The results gleaned from the commission were discussed at symposiums organized by the FIG. In accordance with these studies, scientists interested in the subject have begun to work on models that investigate cause and effect relations between the effects that cause deformation and deformation. As of the scientist who interest with the issue focused on different deformation methods, another special commission was established within the FIG engineering measurements commission in order to classify deformation models and study terminology. After studying this material for a long time, the official commission report was published in 2001. In this prepared report, studies have been carried out by considering the FIG Engineering Surveying Commission's report entitled, 'MODELS AND TERMINOLOGY FOR THE ANALYSIS OF GEODETIC MONITORING OBSERVATIONS

  10. Study on dynamic anti-sliding stability of a high gravity dam considering complex dam foundation

    Deng-hong CHEN; Cheng-bin DU


    There existed some limitations when analyzing the anti-sliding seismic stability of dam-foundation system by traditional pseudo-static method and response spectrum method. The dynamic strength reduction method was used to study on the deep anti-sliding stability of a high gravity dam considering complex dam foundation under strong earthquake-induced ground action. The static analysis was firstly carried out by reducing the shear strength parameters of the dam foundation’s rock mass with equal...

  11. 78 FR 60271 - Hollow Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of Application for Transfer of...


    ... Federal Energy Regulatory Commission Hollow Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of..., Hollow Dam Power Company (transferor) and Ampersand Hollow Dam Hydro, LLC (transferee) filed an application for transfer of license for the Hollow Dam Project, FERC No. 6972, located on the West Branch...

  12. Numerical modelling for stability of tailings dams

    Auchar, Muhammad; Mattsson, Hans; Knutsson, Sven


    A tailings dam is a large embankment structure that is constructed to store the waste from the mining industry. Stability problems may occur in a tailings dam due to factors such as quick rate of raising, internal erosion and liquefaction. The failure of a tailings dam may cause loss of human life and environmental degradation. Tailings Dams must not only be stable during the time the tailings storage facility is in operation, but also long time after the mine is closed. In Sweden, the licens...

  13. Debris Flow Dam Formation in Southeast Tibet

    CHENG Zunlan; WU Jishan; GENG Xueyong


    Glaciers with their deposits abound in the alpine areas of Southeast Tibet. Large debris flows occur frequently from these deposits and form dams that block streams. In this paper, 3 events of large debris flows reported in Peilong Valley located in Southeast Tibet, and which resulted 2 blocking dams resulted, are discussed in details, focusing on the major factors controlling dam formation. The results shows that the first surge group caused by snow and ice avalanches, ice-lake breaks, and large-scale landslides, with a high peak discharge and high velocity, and an abundance of boulders, are most likely to form blocking dams.

  14. Comprehensive evaluation methods for dam service status

    WU ZhongRu; XU Bo; GU ChongShi; LI ZhanChao


    More than 87000 dams have been built in China,and about one third of them are risky projects.A number of high and ultra-high dams are being constructed in China's western region.The current dam construction practice tends to focus on socio-economic benefits and neglect the environment and ecology.Furthermore,periodic examinations are intended to ensure the structural safety of dams.This paper proposes a general evaluation principle for dam service.This principle stipulates that dam projects should have maximum socio-economic benefits and minimum negative effects on the environment and ecology.To satisfy the general principle of mutual harmony,socio-economic benefits,dam safety,environment,and ecology are analyzed,and the evaluation methods for dam service status are discussed.Then,a fusion algorithm of interlayer assessment is proposed on the basis of evidence theory and the fuzzy comprehensive analysis method.Finally,a comprehensive evaluation model is established.Example analysis shows that the proposed theories and methods can fulfill scientific assessment of the service status of dams.

  15. Safety Aspects of Sustainable Storage Dams and Earthquake Safety of Existing Dams

    Martin Wieland


    Full Text Available The basic element in any sustainable dam project is safety, which includes the following safety elements: ① structural safety, ② dam safety monitoring, ③ operational safety and maintenance, and ④ emergency planning. Long-term safety primarily includes the analysis of all hazards affecting the project; that is, hazards from the natural environment, hazards from the man-made environment, and project-specific and site-specific hazards. The special features of the seismic safety of dams are discussed. Large dams were the first structures to be systematically designed against earthquakes, starting in the 1930s. However, the seismic safety of older dams is unknown, as most were designed using seismic design criteria and methods of dynamic analysis that are considered obsolete today. Therefore, we need to reevaluate the seismic safety of existing dams based on current state-of-the-art practices and rehabilitate deficient dams. For large dams, a site-specific seismic hazard analysis is usually recommended. Today, large dams and the safety-relevant elements used for controlling the reservoir after a strong earthquake must be able to withstand the ground motions of a safety evaluation earthquake. The ground motion parameters can be determined either by a probabilistic or a deterministic seismic hazard analysis. During strong earthquakes, inelastic deformations may occur in a dam; therefore, the seismic analysis has to be carried out in the time domain. Furthermore, earthquakes create multiple seismic hazards for dams such as ground shaking, fault movements, mass movements, and others. The ground motions needed by the dam engineer are not real earthquake ground motions but models of the ground motion, which allow the safe design of dams. It must also be kept in mind that dam safety evaluations must be carried out several times during the long life of large storage dams. These features are discussed in this paper.

  16. Mechanical effects of excavation rebound of arch dam bedrock and better concreting time of dam body


    In high ground stress zone, rebound deformation of excavation of arch dam bedrock has a significant impact on the structural behavior, design and construction of arch dam. Based on the analysis of mechanical effects of excavation rebound, with both stress and deformation as two constraint conditions and deformation modulus as a controlling condition, the method to determine a better concreting time of dam body was put forward. All of these play an important guiding role in the excavation of dam bedrock and the construction of dam body.

  17. McNary Dam, Ice Harbor Dam, and Lower Monumental Dam Smolt Monitoring Program; 1996 Annual Report.

    Hillson, Todd; Lind, Sharon; Price, William (Washington Department of Fish and Wildlife, Olympia, WA)


    The Washington Department of Fish & Wildlife (WDFW) assumed responsibility for the Smolt Monitoring Program at McNary Dam on the Columbia River in 1990 and at the new juvenile collection facility at Lower Monumental Dam on the Snake River in 1993. In 1996, Smolt Monitoring Program activities also began at the new juvenile collection facility located at Ice Harbor Dam. This report summarizes the 1996 Smolt Monitoring work at all three sites. The work at Ice Harbor consisted of Gas Bubble Trauma (GBT) monitoring only. In general, the 1996 passage season at both the McNary and Lower Monumental sites can be characterized by reduced passage of juveniles through the collection systems due to elevated river flows and spill, and low (<1%) overall facility mortality rates most likely resulting from cooler water temperatures. In accordance with the National Marine Fisheries Service recommendations (NMFS, 1995) all spring migrants were bypassed at McNary Dam in 1996. Mechanical problems within the McNary collection system resulted in collection and sampling activities being delayed until April 18 at this site, while sampling and collection began on the scheduled starting date of April 1 at Lower Monumental Dam. Monitoring operations were conducted through December 14 at McNary Dam and through October 28 at Lower Monumental Dam. An ongoing transportation evaluation summer migrant marking program was conducted at McNary Dam in 1996 by the NMFS. This necessitated the sampling of 394,211 additional fish beyond the recommended sampling guidelines. All total, 509,237 and 31,219 juvenile salmonids were anesthetized and individually counted, examined for scale loss, injuries, and brands by WDFW Smolt Monitoring personnel in 1996 at McNary Dam and Lower Monumental Dam, respectively.

  18. Adaptability to geological faulted foundation of Hardfill dam

    Kun XIONG; Yunlong HE; Yunfeng PENG


    Hardfill dam is a new type of dam which has the advantages of low stress level and even stress distri-bution in a dam body, resulting in low demands to foun-dations. Based on 2D linear elastic and elasto-plastic calculations of gravity dam and Hardfill dam using finite element method (FEM), the stress distribution in a dam body and anti-sliding stabilization is analyzed on the geo-logical faulted foundations with weak weathered rock and soft interlayers. It is concluded that Hardfill dams have better adaptability to geological faulted foundations than gravity dams and is more secure and economically sound.

  19. Vulnerability of aged concrete gravity dams

    Gogoi, I. [Assam Engineering Institute, Guwahati (India). Dept. of Civil Engineering; Maity, D. [Indian Institute of Technology, Guwahati (India). Dept. of Civil Engineering


    This paper presented an analysis procedure to predict the effects of aging on the behavior of concrete gravity dams. A time dependent isotropic damage index was determined, presenting the performance of the dam with increasing age. Results revealed that the degradation process is dependent on the design life of the structure. The influence of damage along the dam height was greater than damage observed along its width. In order to consider the time dependent degradation of concrete owing to environmental factors and mechanical loading, an algorithm was presented in order to forecast the behavior of existing dams and to assess the necessity of retrofitting or decommissioning. It was concluded that dam behavior during seismic excitation is influenced by the effects of both the dam reservoir system and initial earthquake damage. With increasing age, dam displacement increases, but hydrodynamic pressures and stresses exerted by reservoirs decrease. It was recommended that more accurate behavior could be determined if further research into the coupled effect of foundation-dam-reservoir interaction with material non-linearity was considered. 15 refs.,15 figs.

  20. Upgrading of Boundary Dam spillway

    McPhail, Gordon; MacMillan, Dave; Smith, Bert [KGS Group, Winnipeg, (Canada); Lacelle, Justin [SaskPower, Regina, (Canada)


    An initial dam safety review was performed in 2005 and identified a number of concerns; the most critical were insufficient spillway capacity and deficiencies in the condition of the existing spillways. This paper described the challenges faced by the upgrading operation on the 50 year old Boundary Dam spillway started in 2008. SaskPower retained the KGS Group to increase the design spillway capacity to 1200 m3/s and remedy observed defects. The construction project involved maintaining the reservoir at full supply level while the 20m long spillway chute and stilling basin below were completely replaced. The difficulties came from the need to complete each year's construction such that the spillway could potentially pass spring flood flows. This paper showed that the upgrade measures selected for implementation were developed through close dialogue between the owner and the designer, with valuable input provided by a panel of external experts as well as from contractors participating in the design process.

  1. Restoring Environmental Flows by Modifying Dam Operations

    Gregory A. Thomas


    Full Text Available The construction of new dams has become one of the most controversial issues in global efforts to alleviate poverty, improve human health, and strengthen regional economies. Unfortunately, this controversy has overshadowed the tremendous opportunity that exists for modifying the operations of existing dams to recover many of the environmental and social benefits of healthy ecosystems that have been compromised by present modes of dam operation. The potential benefits of dam "re-operation" include recovery of fish, shellfish, and other wildlife populations valued both commercially and recreationally, including estuarine species; reactivation of the flood storage and water purification benefits that occur when floods are allowed to flow into floodplain forests and wetlands; regaining some semblance of the naturally dynamic balance between river erosion and sedimentation that shapes physical habitat complexity, and arresting problems associated with geomorphic imbalances; cultural and spiritual uses of rivers; and many other socially valued products and services. This paper describes an assessment framework that can be used to evaluate the benefits that might be restored through dam re-operation. Assessing the potential benefits of dam re-operation begins by characterizing the dam's effects on the river flow regime, and formulating hypotheses about the ecological and social benefits that might be restored by releasing water from the dam in a manner that more closely resembles natural flow patterns. These hypotheses can be tested by implementing a re-operation plan, tracking the response of the ecosystem, and continually refining dam operations through adaptive management. The paper highlights a number of land and water management strategies useful in implementing a dam re-operation plan, with reference to a variety of management contexts ranging from individual dams to cascades of dams along a river to regional energy grids. Because many of the

  2. Environmental Assessment for Lock and Dam 22 Major Rehabilitation, Ralls County, Missouri and Pike County, Illinois.


    parvula rare - Wild sarsaparilla Aralia nudicaulis rare - Salt meadow grass Leptochloa panlcoides - endangered Jeweled shooting star Dodecatheon...lots rare - Ditch grass Ruppia maritima rare - Small spike-rush Eleocharis parvula rare - Wild sarsaparilla Aralia nudicaulis rare Salt meadow grass

  3. Environmental Assessment. Lock and Dam 16 Major Maintenance, Rock Island County, Illinois, Muscatine County, Iowa


    CONTAINED A SIGNIFICANT NUMBER OF COLOR PAGES WHICH DO NOT REPRODUCE LEGIBLY ON BLACK AND WHITE MICROFICHE. DEPARTMENT OF THE ARMY ROCK ISLAND...selected to minimize impacts to clarity, color , odor, taste, dissolved gas levels, nutrients, and biochemical oxygen demand in the riverine environment...A. -A~iTHp CIIAIRIMAN9 aAY ISLANO D’RAINAGE & LEYE DIST, Al #..f29 Nr4w 5CSTGN, LL r’l2?2 ,’)URY 04A!NIKE DISTRICT9 00!’j’RT GOCH~LE9 CHAT’PVAN 135,l

  4. Research progress on dam-break floods

    Wu, Jiansong


    Because of the catastrophic effects downstream of dam-break failure, more and more researchers around the world have been working on the study of dam-break flows to accurately forecast the downstream inundation mapping. With the rapid development of computer hardware and computing techniques, numerical study on dam-break flows has been a popular research subject. In the paper, the numerical methodologies used to solve the governing partial differential equations of dam-break flows are classified and summarized, and their characteristics and applications are discussed respectively. Furthermore, the fully-developed mathematical models developed in recent decades are reviewed, and also introduced the authors\\' on-going work. Finally, some possible future developments on modeling the dam-break flows and some solutions are presented and discussed. © 2011 IEEE.

  5. Do we need construct more dams?

    Chen, J.; Shi, H.


    This paper reviews global dam development in association with the growths of global population, economy, and energy consumption in the past several decades, and also evaluates contributions of dam development to future world sustainable development. Eventually, this paper answers whether we need more dams in the future or not. The world population has rapidly increased from 1.6 billion in 1900, 2.5 billion in 1950, 6.1 billion in 2000, to 7.0 billion in 2011, and is projected to reach 9.5 billion in 2050; similarly, the world economy has dramatically expanded. To maintain socioeconomic development, the consumption of water, food and energy has increased rapidly as well. However, the total volume of available water resource over the world is limited, the food production largely depends on water supply, and the main energy sources are still oil, coal and gas at present, which are regarded as non-renewable resources. Accordingly, it is expected that we will face serious problems to deal with the challenges of water crisis, food security and energy shortage in the near future. In order to enhance the capability of regulating water resource, a great number of global dams (and related reservoirs) have been constructed in the last one hundred years; currently, almost all large rivers over the world have been regulated by dams. The reservoirs can supply sufficient water for irrigated land to ensure food production, and the associated hydropower stations can generate electricity. This article collects the dam data from the ICOLD (International Commission on Large Dams) and GRanD (Global Reservoir and Dam) databases, and some socioeconomic data, including population, economy, and consumptions of water, food and energy over the world. Analysis of these data reveals that global dam development has a great impact on the world sustainable development. Further, it is concluded that we need further dam development to maintain our future development.

  6. Seismic failure modes and seismic safety of Hardfill dam

    Kun XIONG; Yong-hong WENG; Yun-long HE


    Based on microscopic damage theory and the finite element method, and using the Weibull distribution to characterize the random distribution of the mechanical properties of materials, the seismic response of a typical Hardfill dam was analyzed through numerical simulation during the earthquakes with intensities of 8 degrees and even greater. The seismic failure modes and failure mechanism of the dam were explored as well. Numerical results show that the Hardfill dam remains at a low stress level and undamaged or slightly damaged during an earthquake with an intensity of 8 degrees. During overload earthquakes, tensile cracks occur at the dam surfaces and extend to inside the dam body, and the upstream dam body experiences more serious damage than the downstream dam body. Therefore, under the seismic conditions, the failure pattern of the Hardfill dam is the tensile fracture of the upstream regions and the dam toe. Compared with traditional gravity dams, Hardfill dams have better seismic performance and greater seismic safety.

  7. Seismic Analysis of Morrow Point Dam

    Noble, C R


    The main objective of this study is to perform nonlinear dynamic earthquake time history analyses on Morrow Point Dam, which is located 263 km southwest of Denver, Colorado. This project poses many significant technical challenges, one of which is to model the entire Morrow Point Dam/Foundation Rock/Reservoir system which includes accurate geology topography. In addition, the computational model must be initialized to represent the existing dead loads on the structure and the stress field caused by the dead loads. To achieve the correct dead load stress field due to gravity and hydrostatic load, the computer model must account for the manner in which the dams were constructed. Construction of a dam finite element model with the correct as-built geometry of the dam structure and simply ''turning on'' gravity in the computer model will generally lead to an incorrect initial stress field in the structure. The sequence of segmented lifts typical of dam construction has a significant impact on the static stress fields induced in the dam. In addition, the dam model must also account for the interaction between the adjacent dam segments across the dam contraction joints. As a result of these challenges, it was determined that a significant amount of code development was required in order to accurately simulate the motion of the dam structure. Modifications to the existing slide surfaces are needed to allow for appropriate modeling of the shear keys across the contraction joints. Furthermore, a model for hydrodynamic interaction was also implemented into NIKE3D and DYNA3D for fluid representation in the 3D dam system finite element model. Finally, the modeling of the 3D dam system results in a very large computational model, which makes it difficult to perform a static initialization using an implicit code. Traditionally, for these large models, the model has been initialized over a long time scale using an explicit code. However, recent advancements


    Gheorghe ROMANESCU


    Full Text Available The dams represent hydrotechnical constructions meant to ensure a judicious use of water resources. The international literature is extremely rich in data regarding the large dams on Earth. In this context, a hierarchy of the main dams is attempted and the role they play in the economic development of the regions they were built in is underlined. The largest dams are built on the big rivers in Asia, North America, South America and Africa. The reservoirs have multiple roles: electricity production, drinking or industrial water supply, irrigations, recreation, etc. High costs and land fragility do not allow the construction of dams in the places most affected by drought or flood. This is why they are usually built in mountainous areas, at great distance from the populated centres. On the Romanian territory, there are 246 large dams, built in the hydrographical basins of Siret, Olt, Arges, Somes, etc. The largest rivers on Earth, by discharge, (Amazon and Zair do not also include the largest dams because the landform and the type of flow have not allowed such constructions.

  9. Nonlinear Seismic Analysis of Morrow Point Dam

    Noble, C R; Nuss, L K


    This research and development project was sponsored by the United States Bureau of Reclamation (USBR), who are best known for the dams, power plants, and canals it constructed in the 17 western states. The mission statement of the USBR's Dam Safety Office, located in Denver, Colorado, is ''to ensure Reclamation dams do not present unacceptable risk to people, property, and the environment.'' The Dam Safety Office does this by quickly identifying the dams which pose an increased threat to the public, and quickly completing the related analyses in order to make decisions that will safeguard the public and associated resources. The research study described in this report constitutes one element of USBR's research and development work to advance their computational and analysis capabilities for studying the response of dams to strong earthquake motions. This project focused on the seismic response of Morrow Point Dam, which is located 263 km southwest of Denver, Colorado.

  10. Ririe Dam Release Test Assessment


    72 Lyme Road Hanover, NH 03755-1290 Stephen Hall and Jeremy Giovando US Army Engineer District, Walla Walla 201 North Third Avenue Walla Walla...11/2013 at 0330 2/12/2013 at 1410 10120114 95th St. (1) 10120115 55th St. (2) 2/11/2013 at 1010 2/12/2013 at 2120 10120111 55th St. (1) 9737377...Ririe Dam 2/10/2013 at 1440 0 hr 64,700 N 95th E 2/12/2013 at 1410 47 hr 30 min 0.32 0.32 33,020 55th St. Bridge 2/12/2013 at 2120 54 hr 40 min

  11. The geomorphic legacy of small dams — An Austrian study

    Poeppl, R.E.; Keesstra, S.D.; Hein, T.


    Dams represent one of the most dominant forms of human impact upon fluvial systems during the Anthropocene, as they disrupt the downstream transfer of water and sediments. Removing dams restores river continuity and channel morphology. Both dam construction and dam removal induce geomorphic channel

  12. Mechanical analysis of a gravity dam

    Bergant, Urša


    In the first part of our work we will present the water supply project in Obala and backend Karst regions. The use of the river Reka and its tributary Suhorka is essential, since an amassment is going to be built on it. We decided to build the dam from rolled concrete, which is economically and environmentally better than a paved barrier or a classic concrete dam. The second part of our work includes tension and stability program calculations. The primary dimensions of the dam-taken from a te...

  13. Sustainability of dams-an evaluation approach

    Petersson, E.


    Situated in the stream bed of a river, dams and reservoirs interrupt the natural hydrological cycle. They are very sensitive to all kinds of changes in the catchment, among others global impacts on land use, climate, settlement structures or living standards. Vice versa dams strongly affect the spatially distributed, complex system of ecology, economy and society in the catchment both up- and downstream of the reservoir. The occurrence of negative impacts due to large dams led to serious conflicts about future dams. Nevertheless, water shortages due to climatic conditions and their changes, that are faced by enormous water and energy demands due to rising living standards of a growing world population, seem to require further dam construction, even if both supply and demand management are optimised. Although environmental impact assessments are compulsory for dams financed by any of the international funding agencies, it has to be assumed that the projects lack sustainability. Starting from an inventory of today's environmental impact assessments as an integral part of a feasibility study the presentation will identify their inadequacies with regard to the sustainability of dams. To improve the sustainability of future dams and avoid the mistakes of the past, the planning procedures for dams have to be adapted. The highly complex and dynamical system of interrelated physical and non-physical processes, that involves many different groups of stakeholders, constitutes the need for a model-oriented decision support system. In line with the report of the World Commission of Dams an integrated analysis and structure of the complex interrelations between dams, ecology, economy and society will be presented. Thus the system, that a respective tool will be based on, is analysed. Furthermore an outlook will be given on the needs of the potential users of a DSS and how it has to be embedded in the overall planning process. The limits of computer-based decision-support in the

  14. Geophysics Methods in Electrometric Assessment of Dams

    Davydov, V. A., E-mail:; Baidikov, S. V., E-mail:; Gorshkov, V. Yu., E-mail:; Malikov, A. V., E-mail: [Russian Academy of Sciences, Geophysical Institute, Ural Branch (Russian Federation)


    The safety assessment of hydraulic structures is proposed to be conducted via geoelectric measurements, which are capable of assessing the health of earth dams in their natural bedding without intervention in their structure. Geoelectric measurements are shown as being capable of pinpointing hazardous parts of a dam, including areas of elevated seepage. Applications of such methods are shown for a number of mini-dams in the Sverdlovsk region. Aparameter (effective longitudinal conductivity) that may be used to monitor the safety of hydraulic structures is proposed. Quantitative estimates of this parameter are given in terms of the degree of safely.

  15. Allegheny County Address Points

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains address points which represent physical address locations assigned by the Allegheny County addressing authority. Data is updated by County...

  16. Allegheny County Air Quality

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Air quality data from Allegheny County Health Department monitors throughout the county. Air quality monitored data must be verified by qualified individuals before...

  17. Allegheny County Council Districts

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset portrays the boundaries of the County Council Districts in Allegheny County. The dataset is based on municipal boundaries and City of Pittsburgh ward...

  18. Allegheny County Municipal Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the municipal boundaries in Allegheny County. Data was created to portray the boundaries of the 130 Municipalities in Allegheny County the...

  19. Allegheny County Address Points

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains address points which represent physical address locations assigned by the Allegheny County addressing authority. Data is updated by County...

  20. Allegheny County Council Districts

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset portrays the boundaries of the County Council Districts in Allegheny County. The dataset is based on municipal boundaries and City of Pittsburgh ward...

  1. Allegheny County Municipal Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the municipal boundaries in Allegheny County. Data was created to portray the boundaries of the 130 Municipalities in Allegheny County the...

  2. Reliablity analysis of gravity dams by response surface method

    Humar, Nina; Kryžanowski, Andrej; Brilly, Mitja; Schnabl, Simon


    A dam failure is one of the most important problems in dam industry. Since the mechanical behavior of dams is usually a complex phenomenon existing classical mathematical models are generally insufficient to adequately predict the dam failure and thus the safety of dams. Therefore, numerical reliability methods are often used to model such a complex mechanical phenomena. Thus, the main purpose of the present paper is to present the response surface method as a powerful mathematical tool used to study and foresee the dam safety considering a set of collected monitoring data. The derived mathematical model is applied to a case study, the Moste dam, which is the highest concrete gravity dam in Slovenia. Based on the derived model, the ambient/state variables are correlated with the dam deformation in order to gain a forecasting tool able to define the critical thresholds for dam management.

  3. Discussion on construction and type selection of China high dams

    Zhou Jianping; Yang Zeyan; Chen Guanfu


    At the beginning of 21st century, with the rapid and steady development of China economy, a lot of large scale hydropower projects with large dams from 200 m to 300 m high are being or to be buih. China dam constructions are reaching the level of 300 m high arch dam, 250 high CFRD (concrete face rockfill dam) and 200 m high RCC (roller compacted concrete) gravity dam. Due to the safety and the economy, the type selection for high dams has become the key issue during the argumentation for the hydropower projects, and further efforts are still needed in this aspect for high dams. After reviewing the high dam constructions in China and abroad, authors proposed some advices for the selection of dam types, and hope that it can provide some helpful information for the researches and the design of high dams.

  4. 76 FR 34799 - Permanent Dam Safety Modification at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams, TN


    ... Permanent Dam Safety Modification at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams, TN AGENCY... various alternatives for permanent modifications to the existing dam facilities at Cherokee, Fort Loudoun, Tellico, and Watts Bar dams in Tennessee. The level of review will be determined after the public...

  5. Determination of Seepage and Analysis of Earth Dams (Case Study: Karkheh Dam

    A. Kamanbedast


    Full Text Available Because of the increasing trend of building dam throughout Iran; it is necessary to optimize dam buildings and operations. Dam or Hydropower industry has two types of buildings; normally: (1 Concrete dams (2 Embankment (earth dams. Generally, scientists and engineers use different methods to enhance safety and decrease any errors in calculation due to maintenance of water storage especially hydro structure of the dam. It is necessary to investigate the dam seepage control; commonly used by several methods. Seepage is one of the important issues for design, build and maintenance of dams awareness. Seepage problem and its rules helps scientist to select a suitable method of monitoring and solving such problem. These methods of analysis were carried out at civil and construction project. In this study, one of latest method of investigation of seepage behavior were analytically evaluated and compared with the actual rules. Based on determine results; several suggestions and optimization method were suggested. Therefore, an optimum method was scientifically selected. Besides that, flow condition of porous environment with application of numeric program was analyzed. Finally, all the results were lunched out from seep/w soft which is the most significant program about this matter; use of finite elements method is specified for saturated and unsaturated environment. Thus; leakage and seepage were defined as function of (time and position. Subsequently, the best seepage solutions for the dam constructing were scientifically identified.

  6. Analysis of seismic disaster failure mechanism and dam-break simulation of high arch dam

    Zhang, Jingkui; Zhang, Liaojun


    Based on a Chinese national high arch dam located in a meizoseismal region, a nonlinear numerical analysis model of the damage and failure process of a dam-foundation system is established by employing a 3-D deformable distinct element code (3DEC) and its re-development functions. The proposed analysis model considers the dam-foundation-reservoir coupling effect, influence of nonlinear contact in the opening and closing of the dam seam surface and abutment rock joints during strong earthquakes, and radiation damping of far field energy dissipation according to the actual workability state of an arch dam. A safety assessment method and safety evaluation criteria is developed to better understand the arch dam system disaster process from local damage to ultimate failure. The dynamic characteristics, disaster mechanism, limit bearing capacity and the entire failure process of a high arch dam under a strong earthquake are then analyzed. Further, the seismic safety of the arch dam is evaluated according to the proposed evaluation criteria and safety assessment method. As a result, some useful conclusions are obtained for some aspects of the disaster mechanism and failure process of an arch dam. The analysis method and conclusions may be useful in engineering practice.

  7. Long-term dam safety monitoring of Punt dal Gall arch dam in Switzerland



    The 130 m high Punt dal Gall dam is located at the Swiss-Italian border in the South-eastern part of Switzerland and was completed in 1969.The dam is founded on highly folded and partially crushed dolomite and limestone formations.A grout curtain with an area of 120,000 m 2 was provided for controlling seepage.For the monitoring of the dam deformations five inverted pendulums were installed in the dam and three in the rock foundation of the right abutment outside of the dam.For a seasonal water level fluctuation in the reservoir of about 60 m the maximum amplitude of the radial displacement is 25 mm,which includes both the effects of the water load and temperature effects.Furthermore a comprehensive geodetic network was established,57 joint meters were installed and cracks in the crest gallery are monitored by crack meters.There are also thermometers,piezometers and rocmeters.Springs at the left and right banks of the dam are monitored and chemical analyses of the seepage water and springs are performed regularly.The dam is equipped with strong motion instruments and several near-field earthquakes have been recorded in the past.The paper describes the long-term safety monitoring of this 42 years old arch dam.A short description of the Swiss practice in dam safety monitoring and emergency planning is also given.

  8. Numerical Study of Two-Dimensional Viscous Flow over Dams

    王利兵; 刘宇陆; 涂敏杰


    In this paper, the characteristics of two-dimensional viscous flow over two dams were numerically investigated. The results show that the behavior of the vortices is closely related to the space between two dams, water depth, Fr number and Reynolds number. In addition, the flow properties behind each dam are different, and the changes over two dams are more complex than over one dam. Finally, the relevant turbulent characteristics were analyzed.

  9. Research on Dam Simulation System Based on OpenGL

    Li, Kairong; Wang, Juanni; Zuo, Kui; Yun, Jian

    Dam, not only has great ability to alleviate water shortages especially during the dry season which improve hydropower capacity, but also plays an imporant rule in the river ecosystem. Dam has significant effect in improving our water environment and protecting ecological system.This paper copes with the three-dimensional model of dams and discusses OpenGL modeling, lighting, material, model transformation, perspective transformation technologies to achieve visualization of the dam, and eventually we visualize the dam through concrete examples.

  10. Final Design Analysis : Lake Ladora Dam Repair

    US Fish and Wildlife Service, Department of the Interior — This report is intended to present Rocky Mountain Arsenal with details concerning the remedial repair for Ladora Dam to meet the geotechnical concerns and hydrologic...

  11. Chemical - Elwha River Dam Removal Study

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  12. Dams life; La vie des barrages



    This paper summarizes the conclusions of the annual inspections of French dams in operation (fissures, water oozing, concrete swelling etc..). Only the observations which require a special attention are reported. (J.S.)

  13. White Sturgeon Passage at The Dalles Dam



    Researchers at the USGS Western Fisheries Research Center's Columbia River Research Laboratory, working with the U.S. Army Corps of Engineers, sought to better understand upstream and downstream passage of white sturgeon at dams. A study at The Dalles Dam provided the opportunity to compare two fish ladders; one that passes sturgeon upstream to one that does not, to determine if subtle differences in construction result in better passage of white sturgeon. Researchers conducted a study using a combination of acoustic and radio telemetry technologies to obtain information on juvenile and adult white sturgeon near The Dalles Dam, with the objectives of characterizing the distribution and movements of white sturgeon in the immediate vicinity of the dam and to determine timing and routes of upstream and downstream passage.

  14. Physical - Elwha River Dam Removal Study

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  15. Biological - Elwha River Dam Removal Study

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  16. Risk assessment of tailings facility dam failure

    Hadzi-Nikolova, Marija; Mirakovski, Dejan; Stefanova, Violeta


    This paper presents the consequences of tailings facility dam failure and therefore the needs for its risk assessment. Tailings are fine-grained wastes of the mining industry, output as slurries, due to mixing with water during mineral processing. Tailings dams vary a lot as it is affected by: tailings characteristics and mill output, site characteristics as: topography, hydrology, geology, groundwater, seismicity and available material and disposal methods. The talings which accumulat...

  17. Stability and performance of older dams

    Dharmawardene, W.; Herbig, A.; Morrison, J. [Alberta Environment, AB (Canada); Chan, D. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering


    There are 1300 licensed dams in Alberta. Most were designed and constructed between the late 1940s and the early 1960s. As a rule, compacted earthfill in preglacial and interglacial valleys in southern Alberta was used to construct all dams of moderate height. At these dam sites, the foundations are of valley infill alluvial soils underlain by weak rocks. The best prevailing engineering practices at the time were used to design these dams. It included drilling, soil testing prior to and during construction, and some stability analyses. Despite these measures, a number of the dams built on soft clays suffered significant deformations and cracking of the embankment during construction. A re-examination of the stability of some of the older dams in Alberta, owned by the provincial department of the Environment, was undertaken six years ago using currently accepted design practices. Allowance was made in the new analyses for the presence of shear zones and fissures in the foundation soils, as well as softening caused by wetting. Despite many years of apparently satisfactory service, Factors of Safety that were marginal or deficient were discovered at many dams. The authors presented case histories of three older dams (North and South McGregor, and North Ridge, all located in southern Alberta) for which the long term Factors of Safety were marginal under normal loading. A number of criteria, such as deformation, stress strain curves of foundation materials and the consequence of failure were taken into consideration in assessing and confirming the requirement for repair before any structural modifications were undertaken. Some of the repairs that were carried out were also briefly described. 12 refs., 4 tabs., 5 figs.

  18. Walter Bouldin Dam failure and reconstruction



    Walter Bouldin is one of several hydroelectric developments of Alabama Power Company. On February 10, 1975, an earth embankment section of Walter Bouldin Dam was breached, causing total evacuation of the forebay reservoir and rendering the 225-MW power plant inoperable. The Federal Power Commission instituted an investigation of the dam failure, and a report on the investigation was published in February 1976. Subsequently, an evidentiary hearing was held before an administrative law judge who issued his initial decision on August 19, 1976. The Commission, on April 21, 1977, issued its Opinion No. 795 in which it adopted the initial decision with modifications and terminated the investigation of failure of Walter Bouldin Dam. Opinion No. 795 directs the staff of the Bureau of Power to prepare, for the future guidance of the Commission, a report on the deficiencies which were found in its investigation, together with advice as to how such deficiencies have been and should be remedied. Also, it directs the staff of the Bureau of Power to address certain general recommendations included in the initial decision. This report was prepared in response to that directive and summaries information on the dam failure and its investigation; the evidentiary hearing; the judge's recommendations, the reconstruction of the Bouldin Dam; and the evalution and status of the Federal Energy Regulatory Commission Dam safety program. (LCL)

  19. Reliability Analysis of High Rockfill Dam Stability

    Ping Yi


    Full Text Available A program 3DSTAB combining slope stability analysis and reliability analysis is developed and validated. In this program, the limit equilibrium method is utilized to calculate safety factors of critical slip surfaces. The first-order reliability method is used to compute reliability indexes corresponding to critical probabilistic surfaces. When derivatives of the performance function are calculated by finite difference method, the previous iteration’s critical slip surface is saved and used. This sequential approximation strategy notably improves efficiency. Using this program, the stability reliability analyses of concrete faced rockfill dams and earth core rockfill dams with different heights and different slope ratios are performed. The results show that both safety factors and reliability indexes decrease as the dam’s slope increases at a constant height and as the dam’s height increases at a constant slope. They decrease dramatically as the dam height increases from 100 m to 200 m while they decrease slowly once the dam height exceeds 250 m, which deserves attention. Additionally, both safety factors and reliability indexes of the upstream slope of earth core rockfill dams are higher than that of the downstream slope. Thus, the downstream slope stability is the key failure mode for earth core rockfill dams.



    Traditionally gully erosion has been identified with the dissection of the landscape in agricultural settings but it is also recognized as a prevalent erosion feature in earthen dam auxiliary spillways and embankments. Flows through earthen spillways and over dam embankments, due to large rainfall events, have the potential to erode and breach the dam or spillway and result in catastrophic releases from the reservoir. The gully erosion process in an earthen spillway or on an embankment can be characterized by stages of initiation, development, and migration of a headcut. A headcut is defined as a near vertical drop at the upstream end of a gully. The rate of headcut migration is important in determining the breach potential of an earthen spillway and dam embankment. A research program is being conducted to examine the gully erosion processes of earthen dam auxiliary spillways and embankments. This paper describes: 1) the unique test facilities constructed to examine the dominant factors affecting the erosion of earthen spillways and embankments; 2) the observations of the erosion processes and results to date; and 3) the predictive relationships that have been developed for dam gully erosion research at the ARS Hydraulic Engineering Research Unit laboratory in Stillwater, OK.

  1. Estimating flood inundation caused by dam failures

    Mocan, N. [Crozier and Associates Inc., Collingwood, ON (Canada); Joy, D.M. [Guelph Univ., ON (Canada). School of Engineering; Rungis, G. [Grand River Conservation Authority, Cambridge, ON (Canada)


    Recent advancements in modelling inundation due to dam failures have allowed easier and more illustrative analyses of potential outcomes. This paper described new model and mapping capabilities available using the HEC-RAS hydraulic model in concert with geographic information systems (GIS). The study area was the upper reaches of Canagagigue Creek and the Woolwich Dam near Elmira, Ontario. A hydraulic analysis of a hypothetical dam failure was developed based on the summer probable maximum flood (PMF) event. Limits extended from Woolwich Dam to downstream of the Town of Elmira. An incoming summer PMF hydrograph was set as the upstream boundary condition in the upstream model. Simulation parameters include simulation time-step; implicit weighting factor; water surface calculation tolerance; and output calculation interval. Peak flows were presented, as well as corresponding flood inundation results through the Town of Elmira. The hydraulic model results were exported to a GIS in order to develop inundation maps for emergency management planning. Results from post-processing included inundation maps for each of the simulated time-steps as well as an inundation animation for the duration of the dam breach. It was concluded that the modelling tools presented in the study can be applied to other dam safety assessment projects in order to develop effective and efficient emergency preparedness plans through public consultation and the establishment of impact zones. 1 tab., 2 figs.

  2. Use and application of inflatable dam seals in large concrete dams

    Dickes, G. [Structural Preservation Systems Inc., Hanover, MD (United States)


    The successful installation of inflatable dam seals has been accomplished at several large concrete dams in the United States. This accomplishment was recently realized for the first time in Canada. The minimization of water intrusion caused by failed water stops in monolithic dams by a small diameter inflatable seal is one of the many uses for the device. Many problems encountered at large concrete dams are related to stress control of alkali-aggregate or alkali silica reaction (AAR, ASR), and the inflatable dam seal fits in as part of this control system. Many of the problems with concrete dams are due to AAR which causes concrete to expand, resulting in cracking of concrete and misalignment of equipment as two of the most important issues. A transverse vertical saw cut through the upper section of the concrete structure was one of the methods used to alleviate the stresses brought about by AAR. This method has been used on a number of occasions in both Canada and the United States. Once the saw cut is complete, from the upstream face to the downstream face, controlling the water flow in the kerf (13-19 millimeter) presents a major challenge. Successfully sealing failed water stops and saw cuts was accomplished by installing inflatable dam seals with vertical heights in excess of 38 meters. A specific seal must be designed in each case. Several elements of the composite construction seal meet the engineering requirements set forth by Dam Safety Officials and Engineers and Owners. Some case histories were presented, namely the Harry S. Truman Dam in Missouri, the Tennessee Valley Authority at several sites, the Hiwassee Dam in North Carolina, the Fontana Dam in Tennessee, and the Mactaquac Generating Station in New Brunswick. 10 refs., 11 figs.

  3. 78 FR 59919 - Pershing County Water Conservation District; Notice of Application Accepted for Filing With the...


    ... County Water Conservation District. e. Name of Project: Humboldt River Hydropower Project. f. Location... Patch dam, gates, and penstocks. The hydropower development would include: (1) A 16-foot by 16-foot... responsibilities. m. Due to the project works already existing and the limited scope of the proposed project site...

  4. Game model of safety monitoring for arch dam deformation


    Arch dam deformation is comprehensively affected by water pressure,temperature,dam’s structural behavior and material properties as well as other factors.Among them the water pressure and temperature are external factors(source factors) that cause dam deformation,and dam’s structural behavior and material properties are the internal factors of deformation(resistance factors).The dam deformation is the result of the mutual game playing between source factors and resistance factors.Therefore,resistance factors of structure and materials that reflect resistance character of arch dam structure are introduced into the traditional model,where structure factor is embodied by the flexibility coefficient of dam body and the maximum dam height,and material property is embodied by the elastic modulus of dam.On the basis of analyzing the correlation between dam deformation and resistance factors,the game model of safety monitoring for arch dam deformation is put forward.

  5. The interplay of activists and dam developers : the case of Myanmar’s mega-dams

    Kirchherr, Julian; J. Charles, Katrina; Walton, Matthew J.


    Scholars investigating activism against large dam developments in Asia usually focus on those campaigning, but not on those the campaigns are aimed at–the dam developers. Yet the developers’ perspective is crucial to comprehensively understand the dynamics of social and environmental activism in

  6. Challenges of high dam construction to computational mechanics

    ZHANG Chuhan


    The current situations and growing prospects of China's hydro-power development and high dam construction are reviewed,giving emphasis to key issues for safety evaluation of large dams and hydro-power plants,especially those associated with application of state-of-the-art computational mechanics.These include but are not limited to:stress and stability analysis of dam foundations under external loads;earthquake behavior of dam-foundation-reservoir systems,mechanical properties of mass concrete for dams,high velocity flow and energy dissipation for high dams,scientific and technical problems of hydro-power plants and underground structures,and newly developed types of dam-Roll Compacted Concrete (RCC) dams and Concrete Face Rock-fill (CFR)dams.Some examples demonstrating successful utilizations of computational mechanics in high dam engineering are given,including seismic nonlinear analysis for arch dam foundations,nonlinear fracture analysis of arch dams under reservoir loads,and failure analysis of arch dam-foundations.To make more use of the computational mechanics in high dam engineering,it is pointed out that much research including different computational methods,numerical models and solution schemes,and verifications through experimental tests and filed measurements is necessary in the future.

  7. Design and construction of Nemiscau-1 Dam, the first asphalt core rockfill dam in North America

    Alicescu, V.; Tournier, J.P. [Hydro-Quebec, Montreal, PQ (Canada); Vannobel, P. [Societe d' Energie de la Baie James, Montreal, PQ (Canada)


    The concept of asphalt as a waterproofing medium inside embankment dams was originally developed in Germany in the 1960s. More than 100 asphalt core rockfill (ACRD) dams have been completed or are under construction. They all have a strong record without any seepage problems or required maintenance. After using the glacial till as waterproofing material for its embankment dams for more than 50 years, Hydro-Quebec is now looking to develop new dam concepts, mainly for the zones where natural waterproofing materials do not exist. In order to do so, the company has decided to design and construct the Nemiscau-1 Dam as a prototype ACRD. This paper presented the detailed design criteria, technical specifications as well as some information concerning the construction of the dam such as asphalt mix design. The given dam site, geology and materials is well suited for a dam with an asphalt core and the chosen core thickness of minimum 400 mm was found to be appropriate, given the small net water head. The main reservoir levels as well as the characteristics of the dam were also listed. Information on the general construction of the dam was provided. It was concluded that the longitudinal profile of the rock excavation and concrete plinth must be optimized, with an optimum balance between the rock excavation, the volume and shape of the concrete plinth and finally, the placement of the asphalt core with the manual method. Several combinations of these 3 elements must be analyzed at the design stage and the most cost effective one should be applied on site. 5 tabs., 7 figs.

  8. Heterogeneous Neutron Capture Record of the Norton County Enstatite Achondrite

    Hidaka, H.; Yoneda, S.


    Large and heterogeneous isotopic variations of Sm and Gd due to neutron capture reactions caused by cosmic-ray irradiation were found in chemical and mineral separates from the Norton County meteorite.


    NIU Zhi-pan; XU Wei-lin; LI Nai-wen; XUE Yang; CHEN Hua-yong


    This paper preseuts results of model tests for the landslide dam failure of a single dam and cascade dams in a sloping channel.The dams were designed to be regular trapezoid with fine sand.A new measuring method named the labeled line locating method was used to digitalize the captured instantaneous pictures.Under two differem inflow discharges,the morphological evolution and the flow patterns during one dam failure and the failure of cascade dams were investigated.The results indicate that when the inflow discharge is large,the deformation pattern of the downstream dam is similar to that of the upstream dam,and both dams are characterized with the overtopping scour throughout the dam failure process.When the inflow discharge is small,the upstream dam is scoured mainly through a sluice slot formed by the longitudinal incision,and the downstream dam is characterized with the overtopping scour.The data set presented in this paper can be used for the validation of numerical models and provide a reference for the flood risk management of cascade landslide dams.

  10. Toward policies and decision-making for dam removal.

    Doyle, Martin W; Harbor, Jon M; Stanley, Emily H


    Dam removal has emerged as a critical issue in environmental management. Agencies responsible for dams face a drastic increase in the number of potential dam removals in the near future. Given limited resources, these agencies need to develop ways to decide which dams should be removed and in what order. The underlying science of dam removal is relatively undeveloped and most agencies faced with dam removal lack a coherent purpose for removing dams. These shortcomings can be overcome by the implementation of two policies by agencies faced with dam removal: (1) the development and adoption of a prioritization scheme for what constitutes an important dam removal, and (2) the establishment of minimum levels of analysis prior to decision-making about a dam removal. Federal and state agencies and the scientific community must encourage an initial experimental phase of dam removal during which only a few dams are removed, and these are studied intensively. This will allow for the development of the fundamental scientific understanding needed to support effective decision-making in the future and minimize the risk of disasters arising from poorly thought out dam removal decisions.

  11. International small dam safety assurance policy benchmarks to avoid dam failure flood disasters in developing countries

    Pisaniello, John D.; Dam, Tuyet Thi; Tingey-Holyoak, Joanne L.


    In developing countries small dam failure disasters are common yet research on their dam safety management is lacking. This paper reviews available small dam safety assurance policy benchmarks from international literature, synthesises them for applicability in developing countries, and provides example application through a case study of Vietnam. Generic models from 'minimum' to 'best' practice (Pisaniello, 1997) are synthesised with the World Bank's 'essential' and 'desirable' elements (Bradlow et al., 2002) leading to novel policy analysis and design criteria for developing countries. The case study involved 22 on-site dam surveys finding micro level physical and management inadequacies that indicates macro dam safety management policy performs far below the minimum benchmark in Vietnam. Moving assurance policy towards 'best practice' is necessary to improve the safety of Vietnam's considerable number of hazardous dams to acceptable community standards, but firstly achieving 'minimum practice' per the developed guidance is essential. The policy analysis/design process provides an exemplar for other developing countries to follow for avoiding dam failure flood disasters.

  12. Re-grouting of Maroon Dam foundation

    Palassi, M. [Tehran Univ. (Iran, Islamic Republic of). Dept. of Civil Engineering; Sharghi, A. [JTMA Co., Tehran (Iran, Islamic Republic of)


    The Maroon dam, built on the Maroon River in the Khoozestan province (southwest) of Iran, has a height of 176 metres and a 1.2 billion cubic metre reservoir. It is one of the largest embankment dams in Iran. A number of unpredicted inflows of water into tunnels and other underground openings occurred during the first impoundment of the Maroon dam. Impoundment was halted and the reservoir was emptied to correct the problem. This paper reviews the measures that were implemented during the remediation process, and presented an evaluation of the effectiveness of the process. The foundation treatment involved placing concrete in the caverns, constructing a concrete lining, and extending the grout curtain. The grouting procedure was also described. The overall effectiveness of the concrete work and grouting resulted in a reduction in leakage from 8.5 cubic metres per second to a more acceptable 10 litres per second. 8 figs.

  13. Channel changes downstream from a dam

    Hadley, R.F.; Emmett, W.W.


    A flood-control dam was completed during 1979 on Bear Creek, a small tributary stream to the South Platte River in the Denver, Colorado, area. Before and after dam closure, repetitive surveys between 1977 and 1992 at five cross sections downstream of the dam documented changes in channel morphology. During this 15-year period, channel width increased slightly, but channel depth increased by more than 40 percent. Within the study reach, stream gradient decreased and median bed material sizes coarsened from sand in the pools and fine gravel on the riffle to a median coarse gravel throughout the reach. The most striking visual change was from a sparse growth of streamside grasses to a dense growth of riparian woody vegetation.

  14. Design of tailing dam using red mud

    Rout, Subrat; Sahoo, Tapaswini; Das, Sarat


    Red mud, waste industrial product from aluminum industries produced approximately 75 million tonnes every year with less than half of this is used. Storage of this unutilized red mud takes vast tracts of usable land and pollutes, land, air and water. Construction of high embankments, under passes, flyovers, tailing dams uses vast tract of natural resources (top soil) is also matter of concern as its takes thousands of years to form the natural soil. This paper discusses use of red mud for construction of tailing dam based on laboratory findings and finite element analysis. The geotechnical properties such as plasticity, compaction, permeability, shear strength characteristics and dispersion of red mud are presented. Stability and seepage analysis of tailing dams as per finite element analysis using the above geotechnical parameters is presented.

  15. Study on dynamic anti-sliding stability of a high gravity dam considering complex dam foundation

    Deng-hong CHEN


    Full Text Available There existed some limitations when analyzing the anti-sliding seismic stability of dam-foundation system by traditional pseudo-static method and response spectrum method. The dynamic strength reduction method was used to study on the deep anti-sliding stability of a high gravity dam considering complex dam foundation under strong earthquake-induced ground action. The static analysis was firstly carried out by reducing the shear strength parameters of the dam foundation’s rock mass with equal proportion. Then, the time-history seismic analysis was carried out based on the static analysis. It was proposed as one of dynamic instability criterions that the peak values of the dynamic displacements and plastic strain energy change suddenly with increasing strength reduction coefficient. The elasto-plastic behavior of the dam foundation was idealized using Drucker–Prager yield criterion based on associated flow rule assumption. Through the static, dynamic strength reduction analysis and dynamic linear elastic analysis of the overflow dam monolith of a high gravity dam, the results’ reliability of elastic-plastic time history analysis was confirmed. The results also showed that the rock mass strength of the high gravity dam foundation has higher strength reserve coefficient. The instability criterions of dynamic strength reduction method proposed were feasible. Although the static anti-slide analysis methods and standards of gravity dam based on the numerical methods are being discussed at present, the dynamic calculation method and instability criterions proposed in this paper would provide some meaningful suggestions for the dynamic analysis of the similar projects.

  16. Optimizing the dammed: water supply losses and fish habitat gains from dam removal in California.

    Null, Sarah E; Medellín-Azuara, Josué; Escriva-Bou, Alvar; Lent, Michelle; Lund, Jay R


    Dams provide water supply, flood protection, and hydropower generation benefits, but also harm native species by altering the natural flow regime and degrading aquatic and riparian habitat. Restoring some rivers reaches to free-flowing conditions may restore substantial environmental benefits, but at some economic cost. This study uses a systems analysis approach to preliminarily evaluate removing rim dams in California's Central Valley to highlight promising habitat and unpromising economic use tradeoffs for water supply and hydropower. CALVIN, an economic-engineering optimization model, is used to evaluate water storage and scarcity from removing dams. A warm and dry climate model for a 30-year period centered at 2085, and a population growth scenario for year 2050 water demands represent future conditions. Tradeoffs between hydropower generation and water scarcity to urban, agricultural, and instream flow requirements were compared with additional river kilometers of habitat accessible to anadromous fish species following dam removal. Results show that existing infrastructure is most beneficial if operated as a system (ignoring many current institutional constraints). Removing all rim dams is not beneficial for California, but a subset of existing dams are potentially promising candidates for removal from an optimized water supply and free-flowing river perspective. Removing individual dams decreases statewide delivered water by 0-2282 million cubic meters and provides access to 0 to 3200 km of salmonid habitat upstream of dams. The method described here can help prioritize dam removal, although more detailed, project-specific studies also are needed. Similarly, improving environmental protection can come at substantially lower economic cost, when evaluated and operated as a system.

  17. Predicting Water Levels at Kainji Dam Using Artificial Neural Networks

    Predicting Water Levels at Kainji Dam Using Artificial Neural Networks. ... The aim of this study is to develop artificial neural network models for predicting water levels at Kainji Dam, which supplies water to Nigeria's largest ... Article Metrics.

  18. Inventory of Dams in the State of Iowa

    Iowa State University GIS Support and Research Facility — Permitted dams in Iowa and associated attributes, as recorded by the Floodplain Section of the DNR. The dams regulated are those with the parameters listed below: a....

  19. National Inventory of Dams Coastal California Extract 2010

    California Department of Resources — The National Inventory of Dams (NID) is a congressionally authorized database, which documents dams in the U.S. and its territories. The NID was most recently...

  20. Research review of the cement sand and gravel (CSG) dam


    The cement sand and gravel (CSG) dam is a new style of dam that owes the advantages both of the concrete faced rock-fill dam (CRFD) and roller compacted concrete (RCC) gravity dam,because of which it has attracted much attention of experts home and abroad.At present,some researches on physic-mechanical property of CSG material and work behavior of CSG dam have been done.This paper introduces the development and characteristics of CSG dam systematically,and summarizes the progress of the study on basic tests,constitutive relation of CSG material and numerical analysis of CSG dam,in addition,indicates research and application aspect of the dam.

  1. Computational Aspects of Dam Risk Analysis: Findings and Challenges

    Ignacio Escuder-Bueno


    Full Text Available In recent years, risk analysis techniques have proved to be a useful tool to inform dam safety management. This paper summarizes the outcomes of three themes related to dam risk analysis discussed in the Benchmark Workshops organized by the International Commission on Large Dams Technical Committee on “Computational Aspects of Analysis and Design of Dams.” In the 2011 Benchmark Workshop, estimation of the probability of failure of a gravity dam for the sliding failure mode was discussed. Next, in 2013, the discussion focused on the computational challenges of the estimation of consequences in dam risk analysis. Finally, in 2015, the probability of sliding and overtopping in an embankment was analyzed. These Benchmark Workshops have allowed a complete review of numerical aspects for dam risk analysis, showing that risk analysis methods are a very useful tool to analyze the risk of dam systems, including downstream consequence assessments and the uncertainty of structural models.

  2. Harvesting river water through small dams promote positive environmental impact.

    Agoramoorthy, Govindasamy; Chaudhary, Sunita; Chinnasamy, Pennan; Hsu, Minna J


    While deliberations relating to negative consequences of large dams on the environment continue to dominate world attention, positive benefits provided by small dams, also known as check dams, go unobserved. Besides, little is known about the potential of check dams in mitigating global warming impacts due to less data availability. Small dams are usually commissioned to private contractors who do not have clear mandate from their employers to post their work online for public scrutiny. As a result, statistics on the design, cost, and materials used to build check dams are not available in public domain. However, this review paper presents data for the first time on the often ignored potential of check dams mitigating climate-induced hydrological threats. We hope that the scientific analysis presented in this paper will promote further research on check dams worldwide to better comprehend their eco-friendly significance serving society.

  3. Dams and transnational advocacy: Political opportunities in transnational collective action

    Fu, Teng

    Possible arguments to explain the gradual decline in big dam development and its site transferring from developed to developing countries include technical, economic, and political factors. This study focuses on the political argument---the rise of transnational anti-dam advocacy and its impact on state policy-making. Under what conditions does transnational anti-dam advocacy matter? Under what conditions does transnational advocacy change state dam policies (delay, scale down, or cancel)? It examines the role of transnational anti-dam actors in big dam building in a comparative context in Asia. Applying the social movement theory of political opportunity structure (POS) and using the qualitative case-study method, the study provides both within-case and cross-case analyses. Within-case analysis is utilized to explain the changing dynamics of big dam building in China (Three Gorges Dam and proposed Nu/Salween River dam projects), and to a lesser extent, Sardar Sarovar Project in India and Nam Theun 2 Dam in Laos. Different domestic and international POS (DPOS and IPOS) impact the strategies and outcomes of anti-dam advocacies in these countries. The degree of openness of the POS directly affects the capacity of transnational efforts in influencing state dam policies. The degree of openness or closure is measured by specific laws, institutions, discourse, or elite allies (or the absence of these) for the participation of non-state actors on big dam issues at a particular moment. This degree of openness is relative, varying over time, across countries and regions. This study finds that the impact of transnational anti-dam activism is most effective when both DPOS and IPOS are relatively open. Transnational anti-dam advocacy is least effective in influencing state dam policies when both DPOS and IPOS are relatively closed. Under a relatively open DPOS and closed IPOS, transnational anti-dam advocacy is more likely to successfully change state dam policies and even

  4. Lac Courte Oreilles Hydro Dam Assessment

    Weaver, Jason [Lac Courte Oreilles, Hayward, WI (United States); Meyers, Amy [Kiser Hydro, LLC, Norway, MI (United States)


    The main objective of this project was to investigate upgrading the existing hydro power generating system at the Winter Dam. The tribe would like to produce more energy and receive a fair market power purchase agreement so the dam is no longer a drain on our budget but a contributor to our economy. We contracted Kiser Hydro, LLC Engineering for this project and received an engineering report that includes options for producing more energy with cost effective upgrades to the existing turbines. Included in this project was a negotiation of energy price sales negotiations.

  5. Research on Dam Perspective Based on Numerical Solution

    WANGZi-ru; ZHOUHui-cheng; LIMing-qiu


    The numerical solution of dam toe line is solved based on the dam data and topographic map of dam located. The display of dam perspective is also realized by programming of using VC++ and OpenGL. The research results above provide the foundation of construction design, construction lofting and information inquiry, which avoids the drawbacks of only using blueprints to do the same work in the past. The method used is useful in practical engineering.

  6. Investigation on the Causes of Cracking in Earth Dams (Case study: Mahmood-Abad Earth Dam

    H. Rahimi


    Full Text Available Introduction: Cracking of earth dams is a one of the main threat causes of stability of embankment dams. In this research by modeling of the behavior of an embankment dam and employing conditions of the earthquake, the reasons of cracking were inspected using by modeling of earth dam behavior. Based on the literature, one of the main causes of dam failures is sliding and cracking of the dam structure during earthquake. Localized liquefaction of foundation soils was one of the causes of the observed post-earthquake distress within these dams. Material and Methods: In order to study the causes and the results of crack on earth dams, Mahmoodabad earthen dam with a height of 19 m, is located in Zanjan province, northwest of Iran, which suffered a longitudinal crack on the crest and slight sliding of the upstream slope due to 2001 Avaj earthquake was studied. This dam has faced earthquake two times with an interval of two years. During the first earthquake with the magnitude about 6.6 in Richter scale small longitudinal cracks had created on the crest. The developed cracks had been repaired by injecting the cement and then has been hidden by passing the time. After the second earthquake with the magnitude about 6.5 in Richter scale the hidden cracks had been appeared again and the slight movement of the upper slopes of dam reported. Based on the site investigation and documented information about dam, including maps and parameter data, the behavior of the dam has modeled by using Plaxis as a finite element model. In order to check the accuracy of the design of dam, the stability analysis has been conducted using by Xslope as a limit equilibrium model. The foundation conditions and the Geotechnical properties of the layer beneath the dam has been inspected by open excavation. Results and Discussion: Underground investigation about Geotechnical properties of dam foundation has showed that there is a thin sandy layer confined in alluvium material of the

  7. Major dams of the United States, Geographic NAD83, USGS (2006) [dams00x020_USGS_2006

    Louisiana Geographic Information Center — This map layer portrays major dams of the United States, including Puerto Rico and the U.S. Virgin Islands. The map layer was created by extracting dams 50 feet or...

  8. 43 CFR 418.18 - Diversions at Derby Dam.


    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Diversions at Derby Dam. 418.18 Section... Operations and Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam must be managed to maintain minimum terminal flow to Lahontan Reservoir or the Carson River...

  9. 25 CFR 173.16 - Reserved area, Coolidge Dam.


    ... 25 Indians 1 2010-04-01 2010-04-01 false Reserved area, Coolidge Dam. 173.16 Section 173.16... area, Coolidge Dam. No permit for any commercial business or other activity (except boating concessions...-fourths of a mile from the center of the Coolidge Dam, Arizona....

  10. 21 CFR 872.6300 - Rubber dam and accessories.


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...


    Bycroft, G.N.; Mork, P.N.


    An analytical solution to the response of a long trapezoidal-section dam on a foundation consisting of an elastic half-space and subjected to simulated earthquake motion is developed. An optimum seismic design is achieved when the cross section of the dam is triangular. The effect of soil structure interaction is to lower the strain occurring in the dam.

  12. The expected collapse of a large dam Saddam Dam in Iraq; Un grand barrage a haut risque Saddam Dam en Irak

    Mesny, M. [Conseil general du genie rural, des eaux et des forets, 75 - Paris (France)


    The Saddam dam is a very large dam in Iraq on the Tigris River, 80 kilometres upstream from the city of Mosul. It is a fill dam with a clayey silt core. The height of the dam is 120 meters and the capacity of the reservoir is 11 billions m3. But this dam has been built on foundations of gypsum that is a rock soluble in water. The impounding of the reservoir in 1986 has shown that, in spite of the grout curtain, substantial seepage has occurred (up to 1.4 m{sup 3}/s), as well as the dissolution of minerals from foundations (up to 80 tons per day). The substantial increase in permeability and seepage through the dam foundations results in a severe concern about the stability of the dam. The program of injection has been stopped in 1991, due to the circumstances. So there is a real risk that this dam would collapse through a quickly developing leak in the dike, resulting in the devastation of the rich agricultural valley of the Tigris River and in potential human losses at Mosul. A 10 to 20-meter high submersion wave would reach this town 3 to 4 hours after the collapse of the dam. An international action is urgently required to check the conditions of the dam and to propose remedial solutions, which may be a 120-meter deep concrete wall down to the calcareous floor existing below the soluble layers of the foundations. (author)

  13. Allegheny County TIF Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Tax Increment Financing (TIF) outline parcels for Allegheny County, PA. TIF closing books contain all necessary documentation related to a TIF in order to close on...

  14. Allegheny County TIF Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Tax Increment Financing (TIF) outline parcels for Allegheny County, PA. TIF closing books contain all necessary documentation related to a TIF in order to close on...

  15. Allegheny County Property Assessments

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Real Property parcel characteristics for Allegheny County, PA. Includes information pertaining to land, values, sales, abatements, and building characteristics (if...

  16. Allegheny County Street Centerlines

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the locations of the street centerlines for vehicular and foot traffic in Allegheny County. Street Centerlines are classified as Primary...

  17. Allegheny County Parks Outlines

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Shows the size and shape of the nine Allegheny County parks. If viewing this description on the Western Pennsylvania Regional Data Center’s open data portal...

  18. Allegheny County Street Centerlines

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the locations of the street centerlines for vehicular and foot traffic in Allegheny County. Street Centerlines are classified as Primary Road,...

  19. Allegheny County Depression Medication

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — These Census Tract-level datasets described here provide de-identified diagnosis data for customers of three managed care organizations in Allegheny County (Gateway...

  20. Allegheny County Diabetes Hospitalization

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This data includes the number of people hospitalized with diabetes between 2013-2015, by age group, for Allegheny County Zip Codes.

  1. Allegheny County Plumbers

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — All master plumbers must be registered with the Allegheny County Health Department. Only Registered Master Plumbers who possess a current plumbing license or...

  2. Westmoreland County Crash Data

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Westmoreland County from 2011 to 2015. Fields include injury severity,...

  3. Allegheny County Crash Data

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Allegheny County from 2004 to 2015. Fields include injury severity,...

  4. County Population Vulnerability

    City and County of Durham, North Carolina — This layer summarizes the social vulnerability index for populations within each county in the United States at scales 1:3m and below. It answers the question...

  5. Beaver County Crash Data

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Beaver County from 2011 to 2015. Fields include injury severity, fatalities,...

  6. Washington County Crash Data

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Washington County from 2011 to 2015. Fields include injury severity,...

  7. Allegheny County Street Centerlines

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the locations of the street centerlines for vehicular and foot traffic in Allegheny County. Street Centerlines are classified as Primary Road,...

  8. Allegheny County Obesity Rates

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Obesity rates for each Census Tract in Allegheny County were produced for the study “Developing small-area predictions for smoking and obesity prevalence in the...

  9. Allegheny County Major Rivers

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains locations of major rivers that flow through Allegheny County. These shapes have been taken from the Hydrology dataset. The Ohio River,...

  10. Allegheny County Boundary

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the Allegheny County boundary. If viewing this description on the Western Pennsylvania Regional Data Center’s open data portal...

  11. Allegheny County Smoking Rates

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Smoking rates for each Census Tract in Allegheny County were produced for the study “Developing small-area predictions for smoking and obesity prevalence in the...

  12. Allegheny County Hospitals

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The data on health care facilities includes the name and location of all the hospitals and primary care facilities in Allegheny County. The current listing of...

  13. Taos County Roads

    Earth Data Analysis Center, University of New Mexico — Vector line shapefile under the stewardship of the Taos County Planning Department depicting roads in Taos County, New Mexico. Originally under the Emergency...

  14. Allegheny County Homicides

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The dataset has location information on homicides that occurred in Allegheny County from 2002-2014. Age group, gender, and race and year of death have been...

  15. Allegheny County Parcel Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains parcel boundaries attributed with county block and lot number. Use the Property Information Extractor for more control downloading a filtered...

  16. Allegheny County Property Viewer

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Webmap of Allegheny municipalities and parcel data. Zoom for a clickable parcel map with owner name, property photograph, and link to the County Real Estate website...

  17. Allegheny County Tobacco Vendors

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The tobacco vendor information provides the location of all tobacco vendors in Allegheny County in 2015. Data was compiled from administrative records managed by...

  18. Allegheny County Asbestos Permits

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Asbestos permit data issued by the County for commercial building demolitions and renovations as required by the EPA. This file is updated daily and can be...

  19. Allegheny County Anxiety Medication

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — These Census Tract-level datasets described here provide de-identified diagnosis data for customers of three managed care organizations in Allegheny County (Gateway...

  20. Butler County Crash Data

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Butler County from 2011 to 2015. Fields include injury severity, fatalities,...

  1. Allegheny County Hypertension Hospitalization

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This data provides hypertension prevalence data for each Zip Code in Allegheny County. The information was produced by Pennsylvania Health Care Cost Containment...

  2. Allegheny County Traffic Counts

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Traffic sensors at over 1,200 locations in Allegheny County collect vehicle counts for the Pennsylvania Department of Transportation. Data included in the Health...

  3. Dams life. Dams in operation; La vie des barrages. Barrages en exploitation



    This paper summarizes the conclusions of the annual inspections of French dams in operation (fissures, water oozing, concrete swelling etc..). Only the observations which require a special attention are reported. (J.S.)

  4. DAM-LAKEFRONT PLAZA: Revitalization of an Agriculture Reservoir Dam in Kashar-Tirana/Albania

    Valbona Koçi


    Full Text Available The Dam-Lakefront Plaza in Kashar-Tirana/Albania is a research project that proposes not only the re-consideration and reinforcement of the artificial Reservoirs Dams built during Socialism in Albania, but envisions the maintenance of dams and revitalization of the lakeside area promoting the public-private collaboration. In addition, it envisions the generation of qualitative and lively public spaces in sub-urban areas as well. Admitting the artificial lakes as specific nodes of man-made infrastructure in the landscape, and consequently the dams (together with the drainage channels as important hydrotechnic elements of the flood protection infrastructure, this research intends to elaborate on one type of landscape infrastructure - the vertical screens, offering a mediation between the natural and built landscape.

  5. 7 CFR 1724.55 - Dam safety.


    ... result from encountering unanticipated or unusual conditions during construction. (5) The independent review of construction shall include: (i) Foundation preparation and treatment. When the foundation has... construction. The reviewer must have demonstrated experience in the design and construction of dams of...

  6. Aquifer performance under the Mactaquac Dam

    Tawil, A.H. [Acres International, Niagara Falls, ON (Canada); Harriman, F.B. [New Brunswick Power, Fredericton, NB (Canada)


    The highest dam in the whole of the Maritimes and New Brunswick in particular is the Mactaquac Dam, with a height of 58 m above the foundation. It forms an integral part of the Mactaquac Hydroelectric Development and the construction of the dam was completed in 1967. Composed of a central core of clay till and external shells of rockfill, it is a zoned embankment. The high artesian pressure rising 6 m above the Saint John River dominates, and the foundation under the dam is composed of a stratum of stiff glacial till underlain with a thick, water bearing aquifer. The aquifer needed to be depressurized during the construction phase and in the long term, and special measures were required to accomplish this. Measurements obtained over a period exceeding 30 years were used to describe the performance of the aquifer, which is discussed in this presentation. A continuous reduction in the yield from the six permanent relief wells in the aquifer was indicated by the instrumentation data. The outflow from the wells diminished by two-thirds over the thirty-four years since first filling the reservoir. The piezometric pressure in the aquifer remained constant over the same period. The sparse results of a two-hour pump test had formed the basis for the design decision not to install a costly foundation seepage cut-off to bedrock, as the conclusions drawn from the pump test were that the aquifer was hydrogeologically confined. 3 refs., 4 tabs., 9 figs.

  7. Increasing dam safety with multi beam sonar

    Bartsch, M. [SwedPower AB, Stockholm (Sweden); Cederstrom, M.O. [Vattenfall AB, Stockholm (Sweden); Deborg, J. [SwedPower AB, Alvkarleby (Sweden)


    Multi-beam sonar technology has been introduced to Vattenfall's dam safety program. Vattenfall is the major energy producer in Sweden and the third largest utility in Europe. Embankment dams are subject to processes such as erosion, settlement and sinkholes. The new portable multi-beam echo sounder system is an important tool to detect minor damages and to intervene before they evolve into expensive or hazardous situations. A first survey of the upstream slope of a rockfill dam with this method provides a topographic map indicating the location of anomalies such as internal erosion or piping. Multi-beam sonar works by combining GPS-RTK positioning, gyro motion sensing, a multi-beam sonar and 3-dimensional digital terrain programs. Vattenfall is using the system to verify and monitor all high hazard rockfill dams in Sweden to ensure long-term stability. The data will be stored as a fingerprint for comparison with future surveys in 15 to 20 years as part of routine safety evaluation. This new technology can also be used to survey breakwaters, erosion of rivers and to locate submerged debris in harbours. 6 figs.

  8. A Final Test for the Big Dam

    LI LI


    @@ The water level at the Three Gorges Dam,the world's largest water control and utilization project,reached its designed highest mark on October 26,which will enable the project to fulfill its functions of flood control,power generation,navigation and water diversion.

  9. Will We. . .? Thai Dam Resource Book.

    Murphy, Richard, Ed.; And Others

    This resource book is intended as an aid to persons working with Thai Dam refugees. To help the language teacher, some differences between Lao and English are discussed, specifically tonal inflections, positioning, declension of pronouns, conjugation of verbs, interrogatives, classifiers and predicate adjectives. An outline of cultural differences…

  10. Resilience scales of a dammed tropical river

    Calamita, Elisa; Schmid, Martin; Wehrli, Bernhard


    Artificial river impoundments disrupt the seasonality and dynamics of thermal, chemical, morphological and ecological regimes in river systems. These alterations affect the aquatic ecosystems in space and time and specifically modify the seasonality and the longitudinal gradients of important biogeochemical processes. Resilience of river systems to anthropogenic stressors enables their recovery along the flow path; however little is known about the longitudinal distance that rivers need to partially restore their physical, chemical and biological integrity. In this study, the concept of a "resilience scale" will be explored for different water quality parameters downstream of Kariba dam, the largest artificial lake in the Zambezi basin (South-East Africa). The goal of this project is to develop a modelling framework to investigate and quantify the impact of large dams on downstream water quality in tropical context. In particular, we aim to assess the degree of reversibility of the main downstream alterations (temperature, oxygen, nutrients) and consequently the quantification of their longitudinal extent. Coupling in-situ measurements with hydraulic and hydrological parameters such as travel times, will allow us to define a physically-based parametrization of the different resilience scales for tropical rivers. The results will be used for improving future dam management at the local scale and assessing the ecological impact of planned dams at the catchment scale.

  11. Fish reproductive guilds downstream of dams.

    Vasconcelos, L P; Alves, D C; Gomes, L C


    Fish reproductive guilds were used to evaluate the responses of species with different reproductive strategies during two different periods of post-dam construction. The data used for the comparisons were collected in the upper Paraná River floodplain (Brazil), downstream of the Porto Primavera dam, 2 and 10 years after impoundment. The abundance (catch per unit effort, CPUE), species richness, evenness and structure of communities, all within reproductive guilds, were used to test the hypothesis that these metrics vary spatially and temporally. The influence of damming on species structure and the diversity of fish reproductive guilds varied spatiotemporally, and species with opportunistic reproductive strategies tended to be less affected. Conversely, long-distance migratory species responded more markedly to spatiotemporal variations, indicating that the ecosystem dynamics exert greater effects on populations of these species. Thus, the effects of a dam, even if attenuated, may extend over several years, especially downstream. This finding emphasizes the importance of maintaining large undammed tributaries downstream of reservoirs.

  12. Modelling approach for gravity dam break analysis

    Boussekine Mourad


    Full Text Available The construction of dams in rivers can provide considerable benefits such as the supply of drinking and irrigation water; however the consequences which would result in the event of their failure could be catastrophic. They vary dramatically depending on the extent of the inundation area, the size of the population at risk.

  13. Experimental research on the dam-break mechanisms of the Jiadanwan landslide dam triggered by the Wenchuan earthquake in China.

    Xu, Fu-gang; Yang, Xing-guo; Zhou, Jia-wen; Hao, Ming-hui


    Dam breaks of landslide dams are always accompanied by large numbers of casualties, a large loss of property, and negative influences on the downstream ecology and environment. This study uses the Jiadanwan landslide dam, created by the Wenchuan earthquake, as a case study example. Several laboratory experiments are carried out to analyse the dam-break mechanism of the landslide dam. The different factors that impact the dam-break process include upstream flow, the boulder effect, dam size, and channel discharge. The development of the discharge channel and the failure of the landslide dam are monitored by digital video and still cameras. Experimental results show that the upstream inflow and the dam size are the main factors that impact the dam-break process. An excavated discharge channel, especially a trapezoidal discharge channel, has a positive effect on reducing peak flow. The depth of the discharge channel also has a significant impact on the dam-break process. The experimental results are significant for landslide dam management and flood disaster prevention and mitigation.

  14. National Dam Safety Program. Lake Thunderhead Dam (MO 10007), Grand - Chariton Basin, Putnam County, Missouri. Phase I Inspection Report.


    1965 by Howard Construction Co., Sedalia, Mo. According to Ms . Quigley, Unionville City Clerk, this project was financed by a loan from the accomplish the d;I=ernz rcquired it will be neoessary to use a multipla sta4e well point instaflsto=. where separate rows of well "oints are drien

  15. National Dam Safety Program. Panama Dam (Inventory Number NY 784) Allegheny River Basin Chautauqua County. Phase I Inspection Report,


    4 ----- 104 - r- -4---4 f-p M.0 W% r- m .0Q0il1 3 : : : C4 m041 &4’ - a -z 1D C>h co 3 (pm f l- nIp4 4. ’rr ~ -n a.. a.£ a.. *m -m m. a-. 4. 4y in In 0 .0 4.0 -4 a 0 I 0 4o 44 .0 4a 0 4 44 0 .0 f .4.44~ ..4 . ... 4.44...4 3 5 0U EZWE 0 t Z ’ . . . .. 4t . . .4LO 000.. .0 ~ m r ~ 4 .44.4

  16. National Dam Safety Program. Koenig Dam (MO 30028), Missouri - Kansas City Basin, St. Charles County, Missouri. Phase I Inspection Report.


    PAGES 210 Tucker Blvd., North, St. Louis, Mo. 63101 Approximately 70 14. MONITORING AGENCY NAME & ADDRESS(II different from Controlling Office) IS...year or month and year as shown on the cover. Block 13. Number of Pages. Enter the total number of pages. Block Monitoring Agency Name and Address (if...0. .. .. .. .. ... ..o. ... _ _.. ... rAND SPILLWAY 200 300 FT. WArER _ _ _ ~~~~70 W TER IAUG 1978 70- 0 100 400 FT. -4L. OF DAN WA ’ER LE

  17. National Dam Safety Program Inspection Report. South Branch Root River. Lanesboro Dam, Fillmore County, Minnesota, Inventory Number 517.


    5/64") ( ) Diagonal (x) wide (more than 2 mm or more C ) Random than 5/64") Mineralization (X) Pattern cracking Leaching C ) Checking ( ) Stalactites ...64") Type Mineralization ( ) Pattern cracking ( ) Leaching ( ) Checking ( ) Stalactites ( ) Hariline cracking ( ) Stalagmites ( ) D-cracking 4...wooden gates in center; 2) exposed masonry left side of structure; 3) large cracks throughout structure; 4) upstream training wall in right foreground

  18. National Dam Safety Program. Westhoff Dam (MO 11140), Mississippi - Salt - Quincy River Basin, Lincoln County, Missouri. Phase I Inspection Report.


    Probable Maximum Flood (PMF) was calculated from the Probable Maximum Precipitation (PMP) using the methods outlined in the U.S. Weather Bureau...12-103 LJtllr H-yDRogjRAPA PAiRAmETegR5 ay JIEOATE 51)S Z) LEF-c4(-rH OF ST R\\t E. IV 2- 000 m~OO C-.*’/ tE-ffv1J ION AT DRAINACjE DVI P~E ALOt.Jq -rHF

  19. National Dam Safety Program. Jones Lake Dam (MO 31486), White River Basin, Oregon County, Missouri. Phase I Inspection Report.


    flows are passed by an uicontrolled , concrete- lined earth cut spillway located in the left abutment. No operating facilities exist. 2.4 EVALUATION... creating an unsafe condition, these deficiencies should only be corrected under the direc- tion of an engineer experienced in the design and construc

  20. National Dam Safety Program. Bedford Reservoir Dam, Inventory Number: VA-01904. Bedford County, Virginia. Phase 1 Inspection Report


    Vfl " /7&>N 11)A (.)\\ ~~𔃻 x . ,’ & - -, - / top. ,’~ edfor ’~"’ ( ’ \\\\~Q , r~-$-~\\ h ~ . N-~(. 74 Nc ) Ni-, A 009’A2D<t. p Řc ibI V I "I ~*1 ,5,. I

  1. National Dam Safety Program. Roxbury Dam (Inventory Number 788) Delaware River Basin, Delaware County, New York. Phase I Inspection Report,


    evaluated and remedied.- t 103 n | mTIOU @9 INOV 5 ,SSoL~eTE. UNCLASSIFIMI SECURITY CLASIFICATION OF T"IS PAGE (When Dete ntered...overturning with seismic considerations included was 2.06 and against sliding was 1.57. Due to the lack of information concerning the embankment materials ...ow____/___R_ Constructed By Owner Cccl-p. 2) Embankment a. Characteristics (1) Embankment Material E ARTN (2) Cutoff Type Pubol. WALL CUTOFF (3

  2. Expectations of immortality: dam safety management into the next millennium

    Palmer, M.D. [Tonkin and Taylor International Ltd., Auckland, (New Zealand)


    Topics concerning the problems associated with older and aging dams are considered including: what can be done to extent the lifetime of an old dam, the decision to decommission a dam based on a value judgment that the risk of maintaining the dam is too great for society's acceptance, the possibility of change in the level of risk tolerance with time in a technological environment, traditional surveillance methods used by dam owners in the Y2K situation, and the unreality of dam immortality. Trends and means for preserving older dams for their owner's purposes are outlined, as well as their lifetime compared to that of the downstream systems they serve. Despite the fact that we live in a throwaway society, dam owners cannot just leave their dam asset when they are through with using it. Someone has to maintain the dam, or ensure that it is safely decommissioned when the owner is finished with it. On a worldwide scale the available pool of experienced dam engineers is shrinking. This problem needs to be addressed by a shift towards operating and dam safety management skills based on a firm awareness of dam design principles. A shift in society's expectations has occurred such that dam designers and owners must now recognize the impact a dam can have both on its natural and social environments. Because of the increasing emphasis on paying attention to the impacts of people's activities on the planet, engineers more than anyone else must have a significant influence in that direction. 9 refs.

  3. Socioeconomic and Institutional Dimensions of Dam Removals: The Wisconsin Experience

    Born; Genskow; Filbert; Hernandez-Mora; Keefer; White


    / There are tens of thousands of small dams in the United States; many of these aging structures are deteriorating. Governments and dam owners face decisions regarding repair or removal of these structures. Along with the many benefits society derives from dams and their impoundments, numerous recent ecological studies are revealing the extensive alteration and degradation of river ecosystems by dams. Dam removal-a principal restoration strategy-is an infrequent event. The major reasons for removal have been public safety and the high costs associated with repair; the goal of river ecosystem restoration now warrants greater attention. Substantial study is being given to the environmental aspects of dams and dam removals, but very little attention has been given to the socioeconomic and institutional dimensions associated with the removal of dams, although these factors play a significant role in the removal decision-making process. Based on a case study of dam removals in Wisconsin-where more than 30 of the state's 3600 small dams have been removed in the past few decades-legal, financial, and socioeconomic issues associated with dam removal are documented and assessed. Dam removal has been complex and contentious, with limited community-based support for removal and loss of the impounded waters. In cases examined here, the estimated costs of repairing a dam averaged more than three times the cost of removal. The availability of governmental financing has been a key determinant in removal decisions. Watershed-scale ecological considerations are not major factors for most local interests. As watershed management and restoration increasingly include dam removal options as part of an integrated strategy, more attention will need to be focused on socioeconomic factors and stakeholder perspectives-variables that strongly influence the viability of this management alternative.KEY WORDS: Dam removal; River restoration; Institutions; Stakeholders

  4. River restoration by dam removal: Enhancing connectivity at watershed scales

    F.J. Magilligan


    Full Text Available Abstract The prolonged history of industrialization, flood control, and hydropower production has led to the construction of 80,000 dams across the U.S. generating significant hydrologic, ecological, and social adjustments. With the increased ecological attention on re-establishing riverine connectivity, dam removal is becoming an important part of large-scale river restoration nationally, especially in New England, due to its early European settlement and history of waterpower-based industry. To capture the broader dimensions of dam removal, we constructed a GIS database of all inventoried dams in New England irrespective of size and reservoir volume to document the magnitude of fragmentation. We compared the characteristics of these existing dams to the attributes of all removed dams over the last ∼25 years. Our results reveal that the National Inventory of Dams significantly underestimates the actual number of dams (4,000 compared to >14,000. To combat the effects of these ecological barriers, dam removal in New England has been robust with 127 dams having been removed between ca. 1990–2013. These removed dams range in size, with the largest number (30% ranging between 2–4 m high, but 22% of the removed dams were between 4–6 m. They are not isolated to small drainage basins: most drained watersheds between 100–1,000 km2. Regionally, dam removal has re-connected ∼3% (3,770 river km of the regional river network although primarily through a few select dams where abundant barrier-free river lengths occur, suggesting that a more strategic removal approach has the opportunity to enhance the magnitude and rate of river re-connection. Given the regional-scale restoration of forest cover and water quality over the past century, dam removal offers a significant opportunity to capitalize on these efforts, providing watershed scale restoration and enhancing watershed resilience in the face of significant regional and global anthropogenic



    With the characteristics of seepage flow in earth-rock dams, a seepage monitoring model was established based on the finite element method for 3-D seepage flow together with observed data and was used to analyze and monitor the seepage of dams. In order to find out and monitor the seepage status of the whole dam, the separation of seepage amount for dam body, dam foundation and side banks was made theoretically by using the model. Practical example shows that the accuracy of computed results is satisfactory and the separation results are more objective.

  6. Design Tools to Assess Hydro-Turbine Biological Performance: Priest Rapids Dam Turbine Replacement Project

    Richmond, Marshall C.; Rakowski, Cynthia L.; Serkowski, John A.; Strickler, Brad; Weisbeck, Molly; Dotson, Curtis L.


    Over the past two decades, there have been many studies describing injury mechanisms associated with turbine passage, the response of various fish species to these mechanisms, and the probability of survival through dams. Although developing tools to design turbines that improve passage survival has been difficult and slow, a more robust quantification of the turbine environment has emerged through integrating physical model data, fish survival data, and computational fluid dynamics (CFD) studies. Grant County Public Utility District (GCPUD) operates the Priest Rapids Dam (PRD), a hydroelectric facility on the Columbia River in Washington State. The dam contains 10 Kaplan-type turbine units that are now almost 50 years old. The Utility District plans to refit all of these aging turbines with new turbines. The Columbia River at PRD is a migratory pathway for several species of juvenile and adult salmonids, so passage of fish through the dam is a major consideration when replacing the turbines. In this presentation, a method for turbine biological performance assessment (BioPA) is introduced. Using this method, a suite of biological performance indicators is computed based on simulated data from a CFD model of a proposed turbine design. Each performance indicator is a measure of the probability of exposure to a certain dose of an injury mechanism. Using known relationships between the dose of an injury mechanism and frequency of injury (dose–response) from laboratory or field studies, the likelihood of fish injury for a turbine design can be computed from the performance indicator. By comparing the values of the indicators from proposed designs, the engineer can identify the more-promising alternatives. We will present application of the BioPA method for baseline risk assessment calculations for the existing Kaplan turbines at PRD that will be used as the minimum biological performance that a proposed new design must achieve.

  7. [Surveillance on the dynamics of leptospirosis epidemics in the Chongqing Section of the Three Gorges dam area].

    Long, Jiang; Wang, Xin-li; Jia, Qing-liang; Li, Qin; Mao, De-qiang; Wu, Guo-hui; Han, Li-su; Ji, Heng-qing


    To analyze the changes of leptospirosis epidemic characteristics before and after the Phase 2 'reservoir store water project' in Chongqing section of the Three Gorges dam area and to provide prevention, control and intervention measures to prevent the spread of leptospirosis from infectious focus to the Three Gorges dam area and downstream region of Changjiang River. Changshou district and Fengdu county were selected as surveillance sites. We monitored the source of infection through examining the serum antibody of patients, healthy groups together with farm cattle measured by micro agglutination test (MAT). Sporadic cases were reported before and after the storage of water in the reservoir. There was no significant difference found between mouse density before and after the Phase 2 reservoir project (chi2 = 1.00, P > 0.05). The main species of rat were Sewer rat before and Insectivorea after the storage of water. The germ-carrying rate of rats was 1.72% (10/583) and positive carrying rate of rats was 16.51% (18/109) when using PCR. Results showed a significant difference when comparing it to culture method (chi2 = 51.80, P leptopirosis occurred in the Three Gorges dam area. There was no significant difference between mouse density before and after the storage of water in the reservoir. However, the major species of rats had a change. The natural infection level of people living in the dam area was low, but there existed potential of leoptopirosis outbreak.

  8. Mining dams safety regulations : where does Canada stand?

    Priscu, C. [AMEC, Winnipeg, MB (Canada); Small, A. [AMEC Earth and Environmental Ltd., Fredericton, NB (Canada); Lupo, J. [AMEC, Englewood, CO (United States); Diaz, M. [AMEC, Ashford, Kent (United Kingdom); Davies, M. [AMEC, Vancouver, BC (Canada); Musse, M. [AMEC, Santiago (Chile)


    While many jurisdictions in Canada use the Canadian Dam Association (CDA) dam safety guidelines, their applicability to the safety of mining dams is limited. Mining dams are some of the largest containment structures in the world, and impound millions of cubic meters of mine process residues in both solid and liquid form. This study presented a review of dam safety regulatory frameworks for mining dams located in various countries. The aim of the study was to compare the Canadian framework with various dam safety legislations in order to evaluate Canada's current status and recommend best practices in dam safety regulations. The study reviewed incremental consequence classifications; best practices in operation, surveillance and maintenance manuals and procedures; emergency preparedness plans; and dam safety inspections. The study showed that Canada has limited documentation regulating the safe management of tailings facilities, and does not have an all-encompassing national guideline for mining dams. It was concluded that an incremental consequence classification (ICC) system should be developed specifically for mining dams. 12 refs.

  9. Seismic failure modes and seismic safety of Hardfill dam

    Kun XIONG


    Full Text Available Based on microscopic damage theory and the finite element method, and using the Weibull distribution to characterize the random distribution of the mechanical properties of materials, the seismic response of a typical Hardfill dam was analyzed through numerical simulation during the earthquakes with intensities of 8 degrees and even greater. The seismic failure modes and failure mechanism of the dam were explored as well. Numerical results show that the Hardfill dam remains at a low stress level and undamaged or slightly damaged during an earthquake with an intensity of 8 degrees. During overload earthquakes, tensile cracks occur at the dam surfaces and extend to inside the dam body, and the upstream dam body experiences more serious damage than the downstream dam body. Therefore, under the seismic conditions, the failure pattern of the Hardfill dam is the tensile fracture of the upstream regions and the dam toe. Compared with traditional gravity dams, Hardfill dams have better seismic performance and greater seismic safety.

  10. Dam failure analysis for the Lago El Guineo Dam, Orocovis, Puerto Rico

    Gómez-Fragoso, Julieta; Heriberto Torres-Sierra,


    The U.S. Geological Survey, in cooperation with the Puerto Rico Electric Power Authority, completed hydrologic and hydraulic analyses to assess the potential hazard to human life and property associated with the hypothetical failure of the Lago El Guineo Dam. The Lago El Guineo Dam is within the headwaters of the Río Grande de Manatí and impounds a drainage area of about 4.25 square kilometers.The hydrologic assessment was designed to determine the outflow hydrographs and peak discharges for Lago El Guineo and other subbasins in the Río Grande de Manatí hydrographic basin for three extreme rainfall events: (1) a 6-hour probable maximum precipitation event, (2) a 24-hour probable maximum precipitation event, and (3) a 24-hour, 100-year recurrence rainfall event. The hydraulic study simulated a dam failure of Lago El Guineo Dam using flood hydrographs generated from the hydrologic study. The simulated dam failure generated a hydrograph that was routed downstream from Lago El Guineo Dam through the lower reaches of the Río Toro Negro and the Río Grande de Manatí to determine water-surface profiles developed from the event-based hydrologic scenarios and “sunny day” conditions. The Hydrologic Engineering Center’s Hydrologic Modeling System (HEC–HMS) and Hydrologic Engineering Center’s River Analysis System (HEC–RAS) computer programs, developed by the U.S. Army Corps of Engineers, were used for the hydrologic and hydraulic modeling, respectively. The flow routing in the hydraulic analyses was completed using the unsteady flow module available in the HEC–RAS model.Above the Lago El Guineo Dam, the simulated inflow peak discharges from HEC–HMS resulted in about 550 and 414 cubic meters per second for the 6- and 24-hour probable maximum precipitation events, respectively. The 24-hour, 100-year recurrence storm simulation resulted in a peak discharge of about 216 cubic meters per second. For the hydrologic analysis, no dam failure conditions are

  11. 75 FR 21341 - Millerton Lake Resource Management Plan/General Plan (RMP/GP), Madera and Fresno Counties, CA


    ... Bureau of Reclamation Millerton Lake Resource Management Plan/General Plan (RMP/GP), Madera and Fresno... Fresno and Madera Counties, CA. The Dam, which regulates the normal flow of the San Joaquin River and stores floodwaters for irrigation diversion into the Friant-Kern and Madera Canals, was completed in 1947...

  12. Gabcikovo dam and Liptovska Mara dam - statistical analysis of measurement data

    Hakac, J.; Sabo, M.


    Introduction: Water level in the observation wells is measured regularly and one of the reasons is evaluation of the safety of the water constructions. In this paper we are exploring the reliability of the measuring devices that are responsible for evaluation of the safety of the two largest and the most important dams in Slovakia. We test ability of selected statistical methods to detect early inaccuracies of measuring devices and thus improve the evaluation of the safety of the water constructions. As a follow-up study, we used the time series model (Neural network) to predict water levels in the observation wells that were considered to be without defects. Neural Network is also able to show dynamics of the filtration stability of the observational well. Methods: On the Liptovska Mara dam weekly data was used as a monitoring tool. On the Gabcikovo dam five minute time series of the measurements of the water level in observation wells around the right lock chamber were used. Data from the measuring devices of the dams were explored with boxplots, correlations, neural network, etc. The mentioned statistical tools analyze time series and detect the errors that measuring devices make when generating data and can be used to predict errors even in real time. In the second step, agreement between predicted data from neural network and measured data in the real time was evaluated. We used grid search for finding the optimal number of neurons and then predicted errors by using this model. The ability of the neural network in evaluation of the sealing of the dilatation joints on the filtration stability in the years 2009 - 2011 is presented. Results: From the 18 selected measuring devices on the Liptovska Mara dam there are only 3 devices which can be considered as reliable. On the Gabcikovo dam, 8 of 9 measuring devices (observation wells around right lock chamber) were considered as a reliable. There was very good agreement between the predicted and measured data at the

  13. Damned If You Do, Dammed If You Don't: Debates on Dam Removal in the Swedish Media

    Dolly Jørgensen


    Full Text Available Dam removal is an increasingly common practice. Dams are removed for various reasons, with safety, economics, and ecosystem restoration being the most common. However, dam removals often cause controversy. Riparian land owners and local communities often have a negative view of removal, and their reasons vary. It may be the loss of recreational benefits such as swimming and boating, loss of cultural and historical context tied to the dam, or fear that removal may have a negative effect on aesthetic values. Because controversies are often picked up by local media, and media in itself is an important channel to build support around a cause, the way in which dam removals are reported and discussed in the media is likely to influence the debate. Here, we examine the ways in which proponents and opponents of dam removal frame the services provided by two contrasting ecosystems, i.e., an existing dam and the potential stream without a dam, by performing a media discourse analysis of the reasons given for removal and the reasons presented for the dam to remain in place. Our source material includes Internet-based newspaper articles and their associated public comments in four dam removal controversies in Sweden. Our analysis indicates that public opposition is not based on knowledge deficiency, where more information will lead to better ecological decision-making, as is sometimes argued in dam removal science; it is instead a case of different understandings and valuation of the environment and the functions it provides.

  14. Dam-breach analysis and flood-inundation mapping for selected dams in Oklahoma City, Oklahoma, and near Atoka, Oklahoma

    Shivers, Molly J.; Smith, S. Jerrod; Grout, Trevor S.; Lewis, Jason M.


    Dams provide beneficial functions such as flood control, recreation, and storage of water supplies, but they also entail risk; dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure or improper operation probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning an emergency response if a dam breach occurs.

  15. GIS inundation mapping and dam breach analysis of Woolwich Dam using HEC-geoRAS

    Mocan, N. [Crozier and Associates Inc., Collingwood, ON (Canada); Joy, D.M. [Guelph Univ., ON (Canada); Rungis, G. [Grand River Conservation Authority, Cambridge, ON (Canada)


    A study was conducted to determine the extent of flood inundation given a hypothetical dam breach scenario of the Woolwich Dam located in the Grand River Watershed, 2.5 km north of the Town of Elmira, Ontario. The dam is operated by the Grand River Conservation Authority and was constructed to provide low-flow augmentation to Canagagigue Creek. Advances in the computational capabilities of numerical models along with the availability of fine resolution geospatial data has lead to significant advances in the evaluation of catastrophic consequences due to the ensuing flood waters when dams fail. The hydraulic models HEC-RAS and HEC-GeoRAS were used in this study along with GIS to produce high resolution spatial and temporal flood inundation mapping. Given the proximity to the Town of Elmira, the dam is classified as having a high hazard potential. The large size and high hazard potential of the dam suggests that the Inflow Design Flood (IDF) is the Probable Maximum Flood (PMF) event. The outlet structure of the spillway consists of 4 ogee-type concrete spillways equipped with radial gates. A low-level concrete pipe located within the spillway structure provides spillage for maintenance purposes. The full flow capacity of the spillway structure is 297 cubic metres per second at the full supply level of 364.8 metres. In addition to GIS flood inundation maps, this paper included the results of flood hydrographs, water surface profiles and peak flow data. It was concluded that techniques used in this analysis should be considered for use in the development of emergency management planning and dam safety assessments across Canada. 6 refs., 3 tabs., 4 figs.

  16. National Dam Inspection Program. Lake Housatonic Dam and Dike (CT 00026 and CT 01714). Connecticut Coastal Basin, Housatonic River, Derby-Shelton, Connecticut. Phase I Inspection Report.


    8217;’,.-+-.-. ""’"" . .•• "•;. - NATIONAL DAM INSPECTION PROGRAM PHASE I INSPECTION REPORT Identification No.: CT 00026, CT 01714 N *~ Name of Dam: Lake Housatonic Dam and Dike " Town...approach was used between 1868 and 1870 to strengthen the Holyoke dam. The dam that existed there at the time was a timber crib dam, 1,017 feet long and 30

  17. How Big of an Effect Do Small Dams Have? Using Geomorphological Footprints to Quantify Spatial Impact of Low-Head Dams and Identify Patterns of Across-Dam Variation.

    Fencl, Jane S; Mather, Martha E; Costigan, Katie H; Daniels, Melinda D


    Longitudinal connectivity is a fundamental characteristic of rivers that can be disrupted by natural and anthropogenic processes. Dams are significant disruptions to streams. Over 2,000,000 low-head dams (dams on geomorphology and ecology are largely untested. Progress for research and conservation is impaired by not knowing the magnitude of low-head dam impacts. Based on the geomorphic literature, we refined a methodology that allowed us to quantify the spatial extent of low-head dam impacts (herein dam footprint), assessed variation in dam footprints across low-head dams within a river network, and identified select aspects of the context of this variation. Wetted width, depth, and substrate size distributions upstream and downstream of six low-head dams within the Upper Neosho River, Kansas, United States of America were measured. Total dam footprints averaged 7.9 km (3.0-15.3 km) or 287 wetted widths (136-437 wetted widths). Estimates included both upstream (mean: 6.7 km or 243 wetted widths) and downstream footprints (mean: 1.2 km or 44 wetted widths). Altogether the six low-head dams impacted 47.3 km (about 17%) of the mainstem in the river network. Despite differences in age, size, location, and primary function, the sizes of geomorphic footprints of individual low-head dams in the Upper Neosho river network were relatively similar. The number of upstream dams and distance to upstream dams, but not dam height, affected the spatial extent of dam footprints. In summary, ubiquitous low-head dams individually and cumulatively altered lotic ecosystems. Both characteristics of individual dams and the context of neighboring dams affected low-head dam impacts within the river network. For these reasons, low-head dams require a different, more integrative, approach for research and management than the individualistic approach that has been applied to larger dams.

  18. Landfill liners from dam reservoir sediments

    Koś Karolina


    Full Text Available Landfill liners from dam reservoir sediments. Every municipal solid waste landfill has to be properly secured to protect the natural environment from possible leachate. Most often an artificial sealing is used, which is based on a soil liner from cohesive soils (clays, silts. Usability evaluation of bottom sediments from Rzeszowski Reservoir for building these liners was presented in the paper. Sediments from dam reservoirs, gathered as a result of the siltation process, can be a valuable material for earthworks purposes. Determination of their possible ways of usage is important, especially before the planned dredging, because thanks to that this material will not be put on a heap. Based on the analysis of the geotechnical parameters of these sediments it was stated that this material can be preliminary allowed for using in liners.

  19. Augmented Reality to Access Dam Cracks Information

    Fabiana Frata Furlan Peres


    Full Text Available Augmented reality technology is a tool with great potential for application in several areas, including engineering. During the early phases of the enterprise life cycle, as design and construction, augmented reality has been widely used. Concrete dams, during operation and maintenance phase, require regular inspections as part of the necessary activities to keep their structural safety. Cracks are common pathology in these structures that must be detected, mapped and measured as their evolution may evidence structure compromising, need for maintenance or intervention. In this context this paper aims to present a prototype to access in situ the dam cracks information through the use of augmented reality, thus giving a contribution to the effectiveness and efficiency of inspections

  20. Temporal and spatial distribution of dam failure events in China



    Reservoirs play a vital role in economic development and flood control.Nevertheless,both human and natural factors may lead to dam failures with catastrophic consequences.Analyzing the data of dam failure events from 1954 to 2003 and using the method of energy spectrum analysis,this paper studies the periodicity of dam failures.The rate of failure of different dam ages is analyzed.The climate is the main factor affecting the rate of dam failure.Climate diagrams are used to analyze the spatial distribution of dam failure events in China.High rate of dam failure occurs with 25-year and 12.5-year periods.The distribution of the percentage of dam failure shows an L-shape as a function of service age.The first 5 years of operation is known as the "infant period",during which,the probability of dam failure is much higher than during any other periods.The failure rate in areas near or north to the 400 mm annual isopluvial line is notably higher than other areas.In areas with high temperature difference among seasons have a high annual average dam failure rate.

  1. Crack status analysis for concrete dams based on measured entropy

    WU BangBin; WU ZhongRu; CHEN Bo; SU HuaiZhi; BAO TengFei; WANG ShaoWei


    The integrity and safety of concrete dams are seriously affected by the existing cracks in dam bodies,and some serious cracks may cause dam failure or disaster.The propagation of cracks in concrete dams is accompanied by changes in energy distribution,which can be represented by changes in the structure's system entropy.Therefore,the entropy theory can be used in analyzing the behavior of dam cracks.Due to the randomness and locality of crack propagation,it is difficult to predict the location of cracks by traditional monitoring methods.To solve this problem,the influence of spatial positions of monitoring points on inspection zones is represented by a weight index,and the weight index is determined by the distance measure method proposed in this paper.Through the weighted linear fusion method,the entropy of multiple monitoring points is obtained for analyzing the behavior of dam cracks in the selected zones.Meanwhile,the catastrophe theory is used as the variation criterion of an entropy sequence in order to predict the instability time of dam cracks.Case studies are put forward on a high arch dam,and the fusion entropy is calculated according to the monitoring data from strain gauges.Results show that the proposed method can effectively predict the occurrence time and location of dam cracks regardless of the layout of monitoring instruments,and it is a new way to analyze the occurrence and propagation of dam cracks.

  2. Dam removal increases American eel abundance in distant headwater streams

    Hitt, Nathaniel P.; Eyler, Sheila; Wofford, John E.B.


    American eel Anguilla rostrata abundances have undergone significant declines over the last 50 years, and migration barriers have been recognized as a contributing cause. We evaluated eel abundances in headwater streams of Shenandoah National Park, Virginia, to compare sites before and after the removal of a large downstream dam in 2004 (Embrey Dam, Rappahannock River). Eel abundances in headwater streams increased significantly after the removal of Embrey Dam. Observed eel abundances after dam removal exceeded predictions derived from autoregressive models parameterized with data prior to dam removal. Mann–Kendall analyses also revealed consistent increases in eel abundances from 2004 to 2010 but inconsistent temporal trends before dam removal. Increasing eel numbers could not be attributed to changes in local physical habitat (i.e., mean stream depth or substrate size) or regional population dynamics (i.e., abundances in Maryland streams or Virginia estuaries). Dam removal was associated with decreasing minimum eel lengths in headwater streams, suggesting that the dam previously impeded migration of many small-bodied individuals (dams may influence eel abundances in headwater streams up to 150 river kilometers distant, and that dam removal may provide benefits for eel management and conservation at the landscape scale.

  3. Will Dam Removal Increase Nitrogen Flux to Estuaries?

    Arthur J. Gold


    Full Text Available To advance the science of dam removal, analyses of functions and benefits need to be linked to individual dam attributes and effects on downstream receiving waters. We examined 7550 dams in the New England (USA region for possible tradeoffs associated with dam removal. Dam removal often generates improvements for safety or migratory fish passage but might increase nitrogen (N flux and eutrophication in coastal watersheds. We estimated N loading and removal with algorithms using geospatial data on land use, stream flow and hydrography. We focused on dams with reservoirs that increase retention time at specific points of river reaches, creating localized hotspots of elevated N removal. Approximately 2200 dams with reservoirs had potential benefits for N removal based on N loading, retention time and depth. Across stream orders, safety concerns on these N removal dams ranged between 28% and 44%. First order streams constituted the majority of N removal dams (70%, but only 3% of those were classified as high value for fish passage. In cases where dam removal might eliminate N removal function from a particular reservoir, site-specific analyses are warranted to improve N delivery estimates and examine alternatives that retain the reservoir while enhancing fish passage and safety.

  4. Impulsive force of debris flow on a curved dam

    Chjeng-Lun SHIEH; Chia-Hsien TING; Hung-Wen PAN


    Although Sabo dams are an efficient method for river and basin management,traditional Sabo dams have a great impact on ecology and landscape.Moreover,such dams are hit and often damaged by great impulsive force when they block the debris flow.Therefore,alternative shapes for Sabo dam deserve thorough investigation.In this investigation,a curved dam was designed by changing the upstream-dam-surface geometric shape to reduce the impulsive force of the debris flow,with enhanced stability and reduced concrete mass being the anticipated outcomes.In this study,the flume and laboratory facilities simulated the impulsive force of the debris flow to the Sabo dams.Three geometric forms,including vertical,slanted and curved Sabo dams,were used to determine the impulsive force.Impulsive force theories of the debris flow were derived from the momentum equation and the Bernoulli equation.In these,the impulsive force was balanced by the friction force of the Sabo dam and the opposite force of the load cell behind the dam as it was hit by the debris flow.Positive correlations were found when comparing the experimental data with the theoretical results.These findings suggest that our impulsive force theory has predictive validity with regard to the experimental data.The results from both theory and experimental data clearly show that curved dams were sustained less force than the other dams under the same debris flow.This comparison demonstrates the importance of curved geometry for a well-designed Sabo dam.

  5. A climate impact of dam lake and Recep Yazicioglu Gokpinar dam lake sample

    Ülker Güner BACANLI


    Full Text Available Dams have both positive and negative effects on the environment. The most important effect can be defined as the regional climate change. In this study, the impact on Denizli city climate of Vali Recep Yazıcıoğlu Gökpınar Dam Lake was determined. In this study, Denizli city meteorological station (maximum, minimum and mean temperatures, total precipitation and wind speed data were used. Before and after from the dam construction; absolute changes are examined. After the dam construction; maximum, minimum and average temperature increase was observed in all months. A rainfall was observed to be increased in January, February and October on after dam construction, but another times was observed to be decreased. The evaporation and wind speed parameter has been little change. Linear regression, the Mann-Kendall and Sen’s Method for trend analysis were used. All techniques considered here consistently reveal that there are upward trend in maximum, minimum and mean temperatures, wind speed, no trend in precipitation and evaporation.

  6. Seismic performance evaluation of concrete gravity dams

    Yamaguchi, Y.; Sasaki, T.; Kanenawa, K. [Public Works Research Institute, Tsukuba City (Japan); Hall, R.; Yule, D. [United States Army Engineer Research and Development Center, Vicksburg, MS (United States); Matheu, E. [Louisiana State Univ., Baton Rouge, LA (United States); Chudgar, A. [United States Army Corps of Engineers, Washington, DC (United States)


    This paper addresses technical issues related to seismic design practices and current evaluation methods in Japan and the United States. Nonlinear analysis procedures can identify the ultimate capacity of existing concrete dams, taking into account the most critical nonlinear phenomena controlling the response. A numerical model of a non-overflow monolith of Koyna Dam, subject to earthquake motion, is used as a case study to compare the different approaches for seismic evaluation of concrete gravity dams currently employed in the two countries. The complexity of nonlinear analysis procedures and the scarcity of appropriate calibration strategies force analysts to frequently interpret results using their own judgment. It was concluded that the influence of the input parameters and ground excitation on the nonlinear dynamic response should be investigated in order to identify the most critical conditions. It was also suggested that methodologies for qualitative damage estimation based on results from linear analyses could be used to develop a systematic assessment tool and reference framework for the adequate interpretation of results. 14 refs., 2 tabs., 13 figs.

  7. Simulating dam-breach flood scenarios of the Tangjiashan landslide dam induced by the Wenchuan Earthquake

    X. Fan


    Full Text Available Floods from failures of landslide dams can pose a hazard to people and property downstream, which have to be rapidly assessed and mitigated in order to reduce the potential risk. The Tangjiashan landslide dam induced by the Mw = 7.9 2008 Wenchuan earthquake had impounded the largest lake in the earthquake affected area with an estimated volume of 3 × 108 m3, and the potential catastrophic dam breach posed a serious threat to more than 2.5 million people in downstream towns and Mianyang city, located 85 km downstream. Chinese authorities had to evacuate parts of the city until the Tangjiashan landslide dam was artificially breached by a spillway, and the lake was drained. We propose an integrated approach to simulate the dam-breach floods for a number of possible scenarios, to evaluate the severity of the threat to Mianyang city. Firstly, the physically-based BREACH model was applied to predict the flood hydrographs at the dam location, which were calibrated with observational data of the flood resulting from the artificial breaching. The output hydrographs from this model were inputted into the 1-D–2-D SOBEK hydrodynamic model to simulate the spatial variations in flood parameters. The simulated flood hydrograph, peak discharge and peak arrival time at the downstream towns fit the observations. Thus this approach is capable of providing reliable predictions for the decision makers to determine the mitigation plans. The sensitivity analysis of the BREACH model input parameters reveals that the average grain size, the unit weight and porosity of the dam materials are the most sensitive parameters. The variability of the dam material properties causes a large uncertainty in the estimation of the peak flood discharge and peak arrival time, but has little influence on the flood inundation area and flood depth downstream. The effect of cascading breaches of smaller dams downstream of the Tangjiashan dam was

  8. Do Hydroelectric Dams Mitigate Global Warming? The Case of Brazil's Curuna Dam

    Fearnside, P.M. [National Institute for Research in the Amazon (INPA), C.P. 478, 69011-970 Manaus, Amazonas (Brazil)


    Hydroelectric dams in tropical forest areas emit greenhouse gases, as illustrated by the Curuna dam in the Amazonian portion of Brazil. Emissions include carbon dioxide from decay of the above-water portions of trees that are left standing in the reservoir and methane from soft vegetation that decays under anaerobic conditions on the bottom of the reservoir, especially macrophytes (water weeds) and vegetation that grows in the drawdown zone and is flooded when the reservoir water level rises. Some methane is released from the reservoir surface through bubbling and diffusion, but larger amounts are released from water passing through the turbines and spillway. Methane concentration in the water increases with depth, and the turbines and spillway draw water from sufficient depth to have substantial methane content. In 1990 (13 years after filling), the Curuna Dam emitted 3.6 times more greenhouse gases than would have been emitted by generating the same amount of electricity from oil.

  9. Assessment model of dam operation risk based on monitoring data


    Although the dams produce remarkable social and economic benefits,the threat made by unsafe dams to the life and property of people who live in the lower river area is un-negligible.Based on the monitoring data which reflect the safety condition of dams,the risk degree concept is proposed and the analysis system and model for evaluating risk degree (rate) are established in this paper by combining the reliability theory and field monitoring data.The analysis method for risk degree is presented based on Bayesian approach.A five-grade risk degree system for dam operation risk and corresponding risk degree is put forward according to the safety condition of dams.The operation risks of four cascade dams on some river are analyzed by the model and approach presented here and the result is adopted by the owner.

  10. VT Boundaries - county polygons

    Vermont Center for Geographic Information — (Link to Metadata) The BNDHASH dataset depicts Vermont villages, towns, counties, Regional Planning Commissions (RPC), and LEPC (Local Emergency Planning Committee)...

  11. Predicting surfacing internal erosion in moraine core dams


    Dams that comprise broadly and widely graded glacial materials, such as moraines, have been found to be susceptible to internal erosion, perhaps more than dams of other soil types. Internal erosion washes out fine-grained particles from the filling material; the erosion occurs within the material itself or at an interface to another dam zone, depending on the mode of initiation. Whether or not internal erosion proceeds depend on the adequacy of the filter material. If internal erosion is allo...

  12. Allegheny County Blazed Trails Locations

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Shows the location of blazed trails in all Allegheny County parks. This is the same data used in the Allegheny County Parks Trails Mobile App, available for Apple...

  13. Allegheny County Zip Code Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the zip code boundaries that lie within Allegheny County. These are not clipped to the Allgeheny County boundary. If viewing this...

  14. Allegheny County Blazed Trails Locations

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Shows the location of blazed trails in all Allegheny County parks. This is the same data used in the Allegheny County Parks Trails Mobile App, available for Apple...

  15. Environmental impacts of increased hydroelectric development at existing dams

    Railsback, S. F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cada, G. F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Petrich, C. H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sale, M. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shaakir-Ali, J. A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Watts, J. A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Webb, J. W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)


    This report describes the environmental impacts of a proposed U.S. Department of Energy (DOE) initiative to promote the development of hydropower resources at existing dams. Hydropower development at existing dams has, in general, fewer impacts than development of additional fossil-fueled resources or hydropower at new dams, although potential cumulative impacts of developing multiple hydropower projects have not been explicitly addressed. Environmental review of project impacts and mitigation needs can ensure that additional hydropower development at existing dams can provide a renewable resource with fewer impacts than alternative resources.

  16. Stochastic Boundary Element Analysis of Concrete Gravity Dam

    张明; 吴清高


    Stochastic boundary integral equations for analyzing large structures are obtained from the partial derivatives of basic random variables. A stochastic boundary element method based on the equations is developed to solve engineering problems of gravity dams using random factors including material parameters of the dam body and the foundation, the water level in the upper reaches, the anti-slide friction coefficient of the dam base, etc. A numerical example shows that the stochastic boundary element method presented in this paper to calculate the reliability index of large construction projects such as a large concrete gravity dam has the advantages of less input data and more precise computational results.

  17. Dam operations affect route-specific passage and survival of juvenile Chinook salmon at a main-stem diversion dam

    Perry, Russell W.; Kock, Tobias J.; Couter, Ian I; Garrison, Thomas M; Hubble, Joel D; Child, David B


    Diversion dams can negatively affect emigrating juvenile salmon populations because fish must pass through the impounded river created by the dam, negotiate a passage route at the dam and then emigrate through a riverine reach that has been affected by reduced river discharge. To quantify the effects of a main-stem diversion dam on juvenile Chinook salmon in the Yakima River, Washington, USA, we used radio telemetry to understand how dam operations and river discharge in the 18-km reach downstream of the dam affected route-specific passage and survival. We found evidence of direct mortality associated with dam passage and indirect mortality associated with migration through the reach below the dam. Survival of fish passing over a surface spill gate (the west gate) was positively related to river discharge, and survival was similar for fish released below the dam, suggesting that passage via this route caused little additional mortality. However, survival of fish that passed under a sub-surface spill gate (the east gate) was considerably lower than survival of fish released downstream of the dam, with the difference in survival decreasing as river discharge increased. The probability of fish passing the dam via three available routes was strongly influenced by dam operations, with passage through the juvenile fish bypass and the east gate increasing with discharge through those routes. By simulating daily passage and route-specific survival, we show that variation in total survival is driven by river discharge and moderated by the proportion of fish passing through low-survival or high-survival passage routes.

  18. Allegheny County Block Areas

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset overlays a grid on the County to assist in locating a parcel. The grid squares are 3,500 by 4,500 square feet. The data was derived from original...

  19. Sheridan County Recreation Plan.

    Webster, Elaine

    A pilot project investigating the feasibility of year-round recreational programs in rural counties of populations of less than 10,000 is described in this report. (Sheridan County, Kansas, was chosen as the project site.) Part I, the introductory section, briefly defines recreation and its relation to human needs. Part II provides a geographic…

  20. Allegheny County Block Areas

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset overlays a grid on the County to assist in locating a parcel. The grid squares are 3,500 by 4,500 square feet. The data was derived from original...

  1. Allegheny County Watershed Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the 52 isolated sub-Watersheds of Allegheny County that drain to single point on the main stem rivers. Created by 3 Rivers 2nd Nature based...


    Dan Zarojanu


    Full Text Available In the county of Suceava, the landslides are a real and permanent problem. This paper presents the observations of landslides over the last 30 years in Suceava County, especially their morphology, theirs causes and the landslide stopping measures. It presents also several details regarding the lanslides from the town of Suceava, of Frasin and the village of Brodina.

  3. Hancock County Awards Gala


    Gene Goldman (left), deputy director of NASA's John C. Stennis Space Center, accepts an Award of Excellence from Jack Zink, executive director of the Hancock County Port and Harbor Commission, during the 2008 Annual Hancock County Awards Gala. The Award of Excellence was presented to recognize Stennis Space Center's contribution to NASA's 50 years of excellence in space exploration.

  4. Monitoring health in African dams : the Kamburu dam (Kenya) as a test case

    J.M.V. Oomen


    textabstractDams are among the obvious efforts to improve the economic situation in a developing country. They aim at using locally available natural resources. At present they are among the most popular means for promoting socio-economic development. A significant number of these programmes have be

  5. Advanced numerical simulation of collapsible earth dams

    De Farias, M.M.; Cordao Neto, M.P. [Brasilia Univ., Federal District (Brazil). Dept. of Civil and Environmental Engineering


    This paper discussed a systematic methodology for the hydromechanical coupled numerical analysis of earth dams constructed with unsaturated collapsible soil. Every design stage was considered, including construction, reservoir filling, and advance of saturation front until the steady-state flow condition is attained. A transient analysis of safety factors applicable to 3-dimensional conditions was presented, giving consideration to unsaturated materials and the interrelation between hydraulic and mechanical phenomena by solving equilibrium and continuity conditions at the same time. The finite element method was used to formulate equilibrium and continuity conditions for both soil skeleton and pore water, which necessitated a realistic mechanical model for the stress-strain-suction relation in unsaturated porous material and adequate constitutive models related to water flow and storage, giving special consideration to imposing appropriate boundary conditions for each simulation stage. The methodology was applied to the analysis of earth dams composed of soils at optimum, dry of optimum, and mixed compaction conditions. The dry section simulated dams constructed using poorly compacted, dry material, which are prone to collapse. By strategically placing the optimum materials in the areas of the earth fill that are most stressed, the mixed section could be designed less expensively with the same or better performance as the homogenous section at optimum conditions. The coupled analysis provides a higher safety factor than uncoupled analysis and a realistic picture of end-of-construction pore pressure distribution. The simulation of reservoir filling and saturation front advance permitted clear identification of the initialization, development, and evolution of internal failure mechanisms. 21 refs., 6 tabs., 19 figs.

  6. Quasi-stable Slope-Failure Dams in High Asia

    Shroder, J. F.


    Collapses of steep mountain slopes in the Himalaya, Karakoram, Pamir, Hindu Kush, and Tibetan Plateau are well known as a result of:(1) generally high seismicity in active tectonic areas; (2) prior deglaciation leaving undercut, unstable cliffs; (3) present-day debuttressing of rock cliffs by glacial down-wasting in conditions of global warming; and (4) degradation of permafrost cohesion and water-ice cementation in high mountain slopes. Landslide dams across mountain rivers are also well known worldwide and generally do not endure for long because of the common landslide-lake outburst floods (LLOF) whose discharge is commonly sufficiently large to remove much of the dam in a short time. A number of massive slope-failure dams in south High Asia, however, have endured for centuries and require explanations for the length of duration, whereas recent examples require robust assessment for better predictive hazard analysis. Three main factors contribute to longevity of slope-failure dams: (1) mega-rocks >15-30 m that inhibit dam failure in overflow breaches; (2) mega-porosity wherein incoming discharge to the landslide lake is balanced by subterranean water through-flow within the landslide dam; (3) impermeable clay fills caused by remobilization of prior lacustrine-dammed sediment that impart dam strength to allow lasting integrity for a time, and (4) climate-change induced lake-level lowering. Several examples of long-lived or unusually stable, slope-failure dams associated with pronounced structural/tectonic associations include: (1) Pangong Tso, Ladakh and Tibet; (2) Lake Shewa, Afghanistan; (3) Sarez Lake, Tajikistan; and (4) Lake Hunza, Pakistan. Pangong Tso and Lake Shewa were emplaced thousands of years ago and only Lake Shewa shows some instability of the dam front where percolating water maintains lake level but may be causing new slumping. Sarez Lake behind the Usoi landslide dam was emplaced by an earthquake in 1911 and maintains its level by seepage. Lake

  7. Evaluation Model of Life Loss Due to Dam Failure

    Huang, Dongjing


    Dam failure poses a serious threat to human life, however there is still lack of systematic research on life loss which due to dam failure in China. From the perspective of protecting human life, an evaluation model for life loss caused by dam failure is put forward. The model building gets three progressive steps. Twenty dam failure cases in China are preferably chosen as the basic data, considering geographical location and construction time of dams, as well as various conditions of dam failure. Then twelve impact factors of life loss are selected, including severity degree of flood, population at risk, understanding of dam failure, warning time, evacuation condition, number of damaged buildings, water temperature, reservoir storage, dam height, dam type, break time and distance from flood area to dam. And through principal component analysis, it gets four principal components consisting of the first flood character principle component, the second warning system principle component, the third human character principle component and the fourth space-time impact principle component. After multivariate nonlinear regression and ten-fold validation in combination, the evaluation model for life loss is finally established. And the result of the proposed model is closer to the true value and better in fitting effect in comparison with the results of RESCDAM method and M. Peng method. The proposed model is not only applied to evaluate life loss and its rate under various kinds of dam failure conditions in China, but also provides reliable cause analysis and prediction approach to reduce the risk of life loss.

  8. Earthquake safety assessment of concrete arch and gravity dams

    Lin Gao; Hu Zhiqiang


    Based on research studies currently being carried out at Dalian University of Technology, some important aspects for the earthquake safety assessment of concrete dams are reviewed and discussed. First, the rate-dependent behavior of concrete subjected to earthquake loading is examined, emphasizing the properties of concrete under cyclic and biaxial loading conditions. Second, a modified four-parameter Hsieh-Ting-Chen viscoplastic consistency model is developed to simulate the rate-dependent behavior of concrete. The earthquake response of a 278m high arch dam is analyzed, and the results show that the strain-rate effects become noticeable in the inelastic range. Third, a more accurate non-smooth Newton algorithm for the solution of three-dimensional frictional contact problems is developed to study the joint opening effects of arch dams during strong earthquakes. Such effects on two nearly 300m high arch dams have been studied. It was found that the canyon shape has great influence on the magnitude and distribution of the joint opening along the dam axis. Fourth, the scaled boundary finite element method presented by Song and Wolf is employed to study the dam-reservoir-foundation interaction effects of concrete dams. Particular emphases were placed on the variation of foundation stiffness and the anisotropic behavior of the foundation material on the dynamic response of concrete dams. Finally, nonlinear modeling of concrete to study the damage evolution of concrete dams during strong earthquakes is discussed. An elastic-damage mechanics approach for damage prediction of concrete gravity dams is described as an example. These findings are helpful in understanding the dynamic behavior of concrete dams and promoting the improvement of seismic safety assessment methods.

  9. The World Commission on Dams + 10: Revisiting the Large Dam Controversy

    Deborah Moore


    Full Text Available The World Commission on Dams (WCD was an experiment in multi-stakeholder dialogue and global governance concerned with a subject area – large dams – that was fraught with conflict and controversy. The WCD Report, Dams and Development: A New Framework for Decision-Making, was published in 2000 and accompanied by hopes that broad-based agreements would be forged on how to better manage water and energy development. Ten years later, this special issue of Water Alternatives revisits the WCD and its impacts, exploring the question: Is the WCD still relevant? The editorial team and the Guest Editors of this special issue of Water Alternatives have selected a range of 20 papers, 6 viewpoints, and 4 book reviews that help to illustrate the evolution in the dams debate. The goal of this special issue is to examine the influence and the impacts of the WCD on the dam enterprise, in general, and on the policies and practices of key stakeholders and institutions, and on the development outcomes for affected communities and environments, in particular. In this introduction, the Guest Editors provide an overview of the special issue, exploring the new drivers of dam development that have emerged during the last decade, including climate change and new financiers of dams, and describing the themes emerging from this diverse set of papers and viewpoints. This special issue demonstrates the need for a renewed multi-stakeholder dialogue at multiple levels. This would not be a redo of the WCD, but rather a rekindling and redesigning of processes and forums where mutual understanding, information-sharing, and norm-setting can occur. One of the most promising developments of the last decade is the further demonstration, in case studies described here, that true partnership amongst key stakeholders can produce transformative resource-sharing agreements, showing that many of the WCD recommendations around negotiated decision making are working in practice. We hope

  10. Minimum Reservoir Water Level in Hydropower Dams

    Sarkardeh, Hamed


    Vortex formation over the intakes is an undesirable phenomenon within the water withdrawal process from a dam reservoir. Calculating the minimum operating water level in power intakes by empirical equations is not a safe way and sometimes contains some errors. Therefore, current method to calculate the critical submergence of a power intake is construction of a scaled physical model in parallel with numerical model. In this research some proposed empirical relations for prediction of submergence depth in power intakes were validated with experimental data of different physical and numerical models of power intakes. Results showed that, equations which involved the geometry of intake have better correspondence with the experimental and numerical data.

  11. Hovercraft drill probes Saraji tailings dam


    In early operations at BHP-Utah's Saraji Mine in central Queensland, quantities of coking coal were pumped into the tailings dam because the preparation plant's flotation circuit was unable to handle ultra-fines. A reverse circulating drilling rig mounted on a hovercraft was used to recover 22 samples (representing 9 metres of tailings from 11 x 8 x 0.09 metre cores) in an investigation into whether the tailings can now be treated economically. 1 fig.

  12. Thermal effects of dams in the Willamette River basin, Oregon

    Rounds, Stewart A.


    Methods were developed to assess the effects of dams on streamflow and water temperature in the Willamette River and its major tributaries. These methods were used to estimate the flows and temperatures that would occur at 14 dam sites in the absence of upstream dams, and river models were applied to simulate downstream flows and temperatures under a no-dams scenario. The dams selected for this study include 13 dams built and operated by the U.S. Army Corps of Engineers (USACE) as part of the Willamette Project, and 1 dam on the Clackamas River owned and operated by Portland General Electric (PGE). Streamflows in the absence of upstream dams for 2001-02 were estimated for USACE sites on the basis of measured releases, changes in reservoir storage, a correction for evaporative losses, and an accounting of flow effects from upstream dams. For the PGE dam, no-project streamflows were derived from a previous modeling effort that was part of a dam-relicensing process. Without-dam streamflows were characterized by higher peak flows in winter and spring and much lower flows in late summer, as compared to with-dam measured flows. Without-dam water temperatures were estimated from measured temperatures upstream of the reservoirs (the USACE sites) or derived from no-project model results (the PGE site). When using upstream data to estimate without-dam temperatures at dam sites, a typical downstream warming rate based on historical data and downstream river models was applied over the distance from the measurement point to the dam site, but only for conditions when the temperature data indicated that warming might be expected. Regressions with measured temperatures from nearby or similar sites were used to extend the without-dam temperature estimates to the entire 2001-02 time period. Without-dam temperature estimates were characterized by a more natural seasonal pattern, with a maximum in July or August, in contrast to the measured patterns at many of the tall dam sites

  13. Dynamic decision making for dam-break emergency management – Part 2: Application to Tangjiashan landslide dam failure

    M. Peng


    Full Text Available Tangjiashan landslide dam, which was triggered by the Ms = 8.0 Wenchuan earthquake in 2008 in China, threatened 1.2 million people downstream of the dam. All people in Beichuan Town 3.5 km downstream of the dam and 197 thousand people in Mianyang City 85 km downstream of the dam were evacuated 10 days before the breaching of the dam. Making such an important decision under uncertainty was difficult. This paper applied a dynamic decision-making framework for dam-break emergency management (DYDEM to help rational decision in the emergency management of the Tangjiashan landslide dam. Three stages are identified with different levels of hydrological, geological and social-economic information along the timeline of the landslide dam failure event. The probability of dam failure is taken as a time series. The dam breaching parameters are predicted with a set of empirical models in stage 1 when no soil property information is known, and a physical model in stages 2 and 3 when knowledge of soil properties has been obtained. The flood routing downstream of the dam in these three stages is analyzed to evaluate the population at risk (PAR. The flood consequences, including evacuation costs, flood damage and monetized loss of life, are evaluated as functions of warning time using a human risk analysis model based on Bayesian networks. Finally, dynamic decision analysis is conducted to find the optimal time to evacuate the population at risk with minimum total loss in each of these three stages.

  14. Major Dams of the United States - Direct Download

    U.S. Geological Survey, Department of the Interior — This map layer portrays major dams of the United States, including Puerto Rico and the U.S. Virgin Islands. The map layer was created by extracting dams 50 feet or...

  15. Numerical Modeling of Sliding Stability of RCC dam

    Mughieda, O.; Hazirbaba, K.; Bani-Hani, K.; Daoud, W.


    Stability and stress analyses are the most important elements that require rigorous consideration in design of a dam structure. Stability of dams against sliding is crucial due to the substantial horizontal load that requires sufficient and safe resistance to develop by mobilization of adequate shearing forces along the base of the dam foundation. In the current research, the static sliding stability of a roller-compacted-concrete (RCC) dam was modelled using finite element method to investigate the stability against sliding. A commercially available finite element software (SAP 2000) was used to analyze stresses in the body of the dam and foundation. A linear finite element static analysis was performed in which a linear plane strain isoperimetric four node elements was used for modelling the dam-foundation system. The analysis was carried out assuming that no slip will occur at the interface between the dam and the foundation. Usual static loading condition was applied for the static analysis. The greatest tension was found to develop in the rock adjacent to the toe of the upstream slope. The factor of safety against sliding along the entire base of the dam was found to be greater than 1 (FS>1), for static loading conditions.

  16. Safety of Italian dams in the face of flood hazard

    Bocchiola, Daniele; Rosso, Renzo


    Most rivers in Italy are segmented by dams that need rehabilitation because of (1) safety requirements by increasingly risk-averse societies, (2) changes in the downstream river and riparian system after dams building, (3) poor initial design at the time of completion and (4) modified priorities of watershed management. Safe design of flood spillways is a major concern, and requires to cope with low frequency flood hazard. One must estimate flood figures with high return periods (R ⩾ 1000-10,000 years) but statistical methods involve large uncertainties because of the short length of the available records. This paper investigates the return period of the design flood of existing spillways RS of large dams in Italy. We used re-normalized flood frequency approach and regionalization using the Generalized Extreme Value distribution. The estimation of the site specific index flood is carried out by simple scaling with basin area at the regional level. The result show that 55% (245) of the 448 examined dams are equipped by spillway with RS > 10,000; and 71% (315) of the dams have RS > 1000. Conversely, 29% (130) of the dams display RS routing may dampen the outflow hydrograph, but one should carefully account for the need of achieving accurate dam safety assessment of these dams based on site specific investigations, also accounting for global change forcing.

  17. Research advance in safety analysis methods for high concrete dam

    REN; QingWen; XU; LanYu; WAN; YunHui


    High tensile stresses occurred in high concrete dams and in their foundation lead to the growing importance of their safety with the increase of concrete dam height.Without any exiting specification or successful experiences of concrete dams up to 300 m at home and abroad for reference,experts feel obliged to figure out how to perform safety analysis on high concrete dam.This paper involves the main contents and mechanical features of the safety analysis on high concrete dam and shows the current state and progress of the analysis methods.For the insufficiency and problems existing in normative methods,study on modern numerical method such as finite element method must be strengthened to find out the stress control criterion which is in accordance with the methods.Two aspects of the safety analysis of high dam--local damage from material level and integral destruction from structure level--should be considered.For the local damage,we should consider the non-homogeneity of material and strengthen the research of meso-damage mechanics.While for integral destruction of the system of high dam and its foundation,a study on non-strength theory should receive enough concerns.Further,attention should be paid to the research on the failure modes and criterions of high concrete dam failure analysis and safety evaluation,and the effect of uncertainty and classification of safety should be considered too.

  18. Measures of struggle against appearance of cracks in earth dams

    Ibraeva Yulia


    Full Text Available The article describes a method calculation of the basic parameters of the transverse rows of pile of simple printed or precast dam. As well, in this article have been shown all the necessary formulas for this calculation and have been proposed solutions to prevent cracking in the dams.

  19. Geophysical methods for the assessment of earthen dams

    Dams and levees are an integral part of the fluvial system in watersheds. Their stability is of utmost concern to the Nation and to those directly impacted should failure occur. There are some 88,000 dams and 110,000 miles of levees in the USA. Many of those are earthen embankments and structures su...

  20. 33 CFR 117.705 - Beaver Dam Creek.


    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Beaver Dam Creek. 117.705 Section 117.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.705 Beaver Dam Creek. The draw of...

  1. 78 FR 7810 - Glen Canyon Dam Adaptive Management Work Group


    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group.... L. 102-575) of 1992. The AMP includes a Federal advisory committee, the AMWG, a technical work...

  2. 75 FR 34476 - Glen Canyon Dam Adaptive Management Work Group


    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation... Interior (Secretary) is renewing the charter for the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group is to advise and to provide recommendations to the...

  3. 78 FR 21415 - Glen Canyon Dam Adaptive Management Work Group


    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group..., the AMWG, a technical work group, a Grand Canyon Monitoring and Research Center, and...

  4. 77 FR 43117 - Glen Canyon Dam Adaptive Management Work Group


    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... Federal advisory committee, the AMWG, a technical work group (TWG), a Grand Canyon Monitoring and...

  5. 77 FR 9265 - Glen Canyon Dam Adaptive Management Work Group


    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... Federal advisory committee, the AMWG, a technical work group (TWG), a Grand Canyon Monitoring and...

  6. Institutionalizing the option of dam removal: the New Hampshire initiative.

    Lindloff, S D


    For two years, the State of New Hampshire has worked to institutionalize the option of dam removal. The high gradient streams that flow through the granite hills and mountains of this small northeastern state provided ideal conditions for dam construction, particularly during America's Industrial Revolution of the 1800s when mills were constructed throughout the area. With more than 4,800 dams in the state's database, there are many opportunities for the removal of dams that no longer serve a useful purpose, have become a public safety hazard and impact the river environment. Efforts to facilitate removal of dams in New Hampshire include the formation of a River Restoration Task Force and the creation of a dam removal program within the state agency responsible for regulating dams. This has led to the removal of two dams in the past year, with approximately ten additional projects in various stages of planning. A history of this agency-led initiative, as well as a discussion of the program's strengths, challenges and goals for the future are presented.

  7. How to manage the cumulative flood safety of catchment dams


    Sep 15, 2008 ... Sustainable Law and Engineering Group, Centre for Accounting, Governance and Sustainability, ... associated with small-dam safety and practical feedback from ... catchment dams nor the supervision over the management of .... same time in an extreme design flood event of only 1-in-200 ..... These guide-.

  8. Will the Three Gorges Dam Stand The Test of Time?


    @@ Netizens have collected several ar-ticles about the flood-control capacity of the Three Gorges Dam. In these articles, its capacity was differently described as tackling flooding "once-in-10,000-years" "once-in- l,O00-years" or "once-in-a-century" Can you give the specifics of the flood control capacity of the dam?

  9. INTRODUCTION All earth dams in their natural state experience ...

    Earth Dam constructed within the Precambrian Basement Complex terrain of Southwestern Nigeria. The study was aimed at ... The 2-D resistivity structure revealed that the core of the dam embankment is .... within the rain forest region of Nigeria. The ..... (citrus Sinensis Osbeck) Stored at Ambient Tropical Condition. 251.

  10. Seepage problem in Papan dam and the treatment

    Sharghi, A. [JTMA Co., Tehran (Iran, Islamic Republic of); Palassi, M. [Tehran Univ. (Iran, Islamic Republic of). Dept. of Civil Engineering


    The Papan dam in the Krygyz Republic is 97 metres high. It is located in the Osh Oblast, within a narrow and steep sided gorge on the Ak-Bura River, approximately 20 kilometres south of the City of Osh. The impoundment of the dam revealed large inflows of water to the downstream dam through the upper half of the dam and through the joints in the right abutment. A number of options were considered before a treatment method was selected. The causes of the leakage were poor grouting, and joints and fissures in the abutment. The remedial process involved the use of a plastic concrete cutoff wall extended from the crest of the dam to a depth of approximately 70 metres, in addition to the use of a grouting curtain in the right abutment. 2 figs.

  11. Sediment settling in the Latian Dam in Iran

    Farhang BEHRANGI; Mohammad Ali BANIHASHEMI; Shayesteh MAHANI; Mohammad Reza RAHMANIAN


    Among the difficulties that influence future dam operations, reservoir sedimentation is the most problematic for engineers. This study predicted the amount and pattern of sedimentation for use in estimation of the useful lifespan of reservoirs and identification of optimal locations for outlets and intakes at the initial stages of dam design. Hydrographic surveys of different dams can provide better insight into this phenomenon. Latian Dam in Iran has conducted hydrographic surveys during 7 time periods. The amount and process of sedimentation in this reservoir were determined, and predictions of distribution of sediments were validated by well-known, common methods. The formation of a delta in the reservoir was investigated for different time periods after operation. Future problems due to the impacts of sedimentation on dam operation and the useful lifespan of the reservoir were predicted. In addition, the study results may be used for developing empirical methods to predict sedimentation patterns in other reservoirs.

  12. Management of dam safety at BC Hydro: the database tool

    Oswell, Terry [BC Hydrom Burnaby, (Canada)


    BC Hydro has a wide range of dams, which raises a wide range of issues at many unique sites. A dam safety database was developed in 2000 to deal with the complexity and volume of information provided by deficiency investigations and surveillances. The database contains all documented deficiencies and non-conformances identified in the past 10 years. It records the risk ratings assigned to each issue. This paper described the implementation of the database tool, from the characterization of a dam safety issue to the use of the database itself. The dam safety database is now a key tool in managing the dam safety program at BC Hydro and has been useful for the last 10 years or so in prioritizing the program of deficiency investigations and capital projects. The development of a process to rate non-conformances is currently under study and will be implemented soon to aid in more efficient prioritization of maintenance activities.

  13. Modeling Experiment of Break of Debris-Flow Dam

    CHENG Zunlan; GENG Xueyong; DANG Chao; LIU Jingjing


    Glaciers are extensively developed in the southwest of Tibet and the moraines are widely distributed with large depth. Large-scale debris flows are often reported which blocked rivers and formed dams. In this paper, seven large debris flows in four valleys are discussed, among which five dams developed. 13 sets of experiments have been conducted in laboratory to simulate the formation and failure of the dam. Finally, a model of dam failure is proposed and a formula is established to calculate the flood discharge:Q = kbhhk/T (B)/LG0.41, where bk is the outlet width of the dam atthe original water level, ht the erosive depth, T the time fromoverflow to final state of failure, the average width of lake; L thelength of the lake, and G the total potential energy of the water inthe lake.

  14. Dam Inventory - DAMS_1996_EPA_IN: Inventory of Dams in Indiana, Derived from EPA BASINS (United States Environmental Protection Agency, Point Shapefile)

    NSGIC GIS Inventory (aka Ramona) — DAMS_1996_EPA_IN is a point shapefile developed by the USEPA BASINS 3.0 program and clipped by Bernardin, Lochmueller and Associates. Clips were performed using the...

  15. Channel evolution on the dammed Elwha River, Washington, USA

    Draut, A.E.; Logan, J.B.; Mastin, M.C.


    Like many rivers in the western U.S., the Elwha River, Washington, has changed substantially over the past century in response to natural and human forcing. The lower river is affected by two upstream dams that are slated for removal as part of a major river restoration effort. In preparation for studying the effects of dam removal, we present a comprehensive field and aerial photographic analysis of dam influence on an anabranching, gravel-bed river. Over the past century with the dams in place, loss of the upstream sediment supply has caused spatial variations in the sedimentary and geomorphic character of the lower Elwha River channel. Bed sediment is armored and better sorted than on the naturally evolving bed upstream of the dams. On time scales of flood seasons, the channel immediately below the lower dam is fairly stable, but progresses toward greater mobility downstream such that the lowermost portion of the river responded to a recent 40-year flood with bank erosion and bed-elevation changes on a scale approaching that of the natural channel above the dams. In general, channel mobility in the lowest 4 km of the Elwha River has not decreased substantially with time. Enough fine sediment remains in the floodplain that – given sufficient flood forcing – the channel position, sinuosity, and braiding index change substantially. The processes by which this river accesses new fine sediment below the dams (rapid migration into noncohesive banks and avulsion of new channels) allow it to compensate for loss of upstream sediment supply more readily than would a dammed river with cohesive banks or a more limited supply of alluvium. The planned dam removal will provide a valuable opportunity to evaluate channel response to the future restoration of natural upstream sediment supply.

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

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


    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.

  17. Geophysical Investigations at Hidden Dam, Raymond, California Flow Simulations

    Minsley, Burke J.; Ikard, Scott


    Numerical flow modeling and analysis of observation-well data at Hidden Dam are carried out to supplement recent geophysical field investigations at the site (Minsley and others, 2010). This work also is complementary to earlier seepage-related studies at Hidden Dam documented by Cedergren (1980a, b). Known seepage areas on the northwest right abutment area of the downstream side of the dam was documented by Cedergren (1980a, b). Subsequent to the 1980 seepage study, a drainage blanket with a sub-drain system was installed to mitigate downstream seepage. Flow net analysis provided by Cedergren (1980a, b) suggests that the primary seepage mechanism involves flow through the dam foundation due to normal reservoir pool elevations, which results in upflow that intersects the ground surface in several areas on the downstream side of the dam. In addition to the reservoir pool elevations and downstream surface topography, flow is also controlled by the existing foundation geology as well as the presence or absence of a horizontal drain in the downstream portion of the dam. The current modeling study is aimed at quantifying how variability in dam and foundation hydrologic properties influences seepage as a function of reservoir stage. Flow modeling is implemented using the COMSOL Multiphysics software package, which solves the partially saturated flow equations in a two-dimensional (2D) cross-section of Hidden Dam that also incorporates true downstream topography. Use of the COMSOL software package provides a more quantitative approach than the flow net analysis by Cedergren (1980a, b), and allows for rapid evaluation of the influence of various parameters such as reservoir level, dam structure and geometry, and hydrogeologic properties of the dam and foundation materials. Historical observation-well data are used to help validate the flow simulations by comparing observed and predicted water levels for a range of reservoir elevations. The flow models are guided by, and

  18. Safety and coping strategy for high dam under complex natural conditions

    Niu Xinqiang


    In respect to current situation and new challenges for high dam construction in China, safety problems are an- alyzed for high dam construction under complex natural conditions such as high elevation, cold area, high seismic inten- sity, large-seale landslide and high dam and huge reservoirs with dam types such as concrete surface rock-fill, asphalt concrete core, roller compacted concrete (RCC) arch dam and so on. From several aspects, including risk response measures for high dam, strengthening safety awareness for high dam design and construction, improving high dam con- struetion technique, intelligent dam safety management system based on IT, developing dam rehabilitation and mainte- nance technologies, useful dam safety and coping strategy is proposed.

  19. The Political Ecology of Chinese Large Dams in Cambodia: Implications, Challenges and Lessons Learnt from the Kamchay Dam

    Giuseppina Siciliano


    Full Text Available Given the opportunities offered by foreign investment in energy infrastructure mostly by Chinese firms, the Government of Cambodia is giving high priority to developing hydropower resources for reducing energy poverty and powering economic growth. Using a “Political ecology of the Asian drivers” framework, this paper assesses China’s involvement in the development of large dams’ in Cambodia and its impacts on the access of natural resources such as water and energy by dam builders, local communities and the government. This analysis is based on 61 interviews and 10 focus group discussions with affected communities, institutional actors, Chinese dam builders and financiers in relation to the first large Chinese dam built in Cambodia: the Kamchay dam. Based on the results of the analysis this paper makes recommendations on how to improve the planning, implementation and governance of future large dams in Cambodia.

  20. Stability of earth dam with a vertical core

    Orekhov Vyacheslav Valentinovich


    Full Text Available Earth dam with impervious element in the form of asphaltic concrete core is currently the most promising type of earth dams (due to simple construction technology and universal service properties of asphaltic concrete and is widely used in the world. However, experience in the construction and operation of high dams (above 160 m is not available, and their work is scarcely explored. In this regard, the paper discusses the results of computational prediction of the stress-strain state and stability of a high earth dam (256 m high with the core. The authors considered asphaltic concrete containing 7 % of bitumen as the material of the core. Gravel was considered as the material of resistant prisms. Design characteristics of the rolled asphaltic concrete and gravel were obtained from the processing of the results of triaxial tests. The calculations were performed using finite element method in elastoplastic formulation and basing on the phased construction of the dam and reservoir filling. The research shows, that the work of embankment dam with vertical core during filling of the reservoir is characterized by horizontal displacement of the lower resistant prism in the tailrace and the formation of a hard wedge prism descending along the core in the upper resistant prism. The key issue of the safety assessment is to determine the safety factor of the overall stability of the dam, for calculation of which the destruction of the earth dam is necessary, which can be done by reducing the strength properties of the dam materials. As a results of the calculations, the destruction of the dam occurs with a decrease in the strength characteristics of the materials of the dam by 2.5 times. The dam stability depends on the stability of the lower resistant prism. The destruction of its slope occurs on the classical circular-cylindrical surface. The presence of a potential collapse surface in the upper resistant prism (on the edges of the descending wedge does


    Federal Emergency Management Agency, Department of Homeland Security — Solano County California, hydrographic survey data collected by Harned Surveying and Engineering (HSE). Data collection period January 1, 2011 through March 1, 2011.

  2. Allegheny County Sheriff Sales

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — List of properties up for auction at a Sheriff Sale. Datasets labeled "Current" contain this month's postings, while those labeled "Archive" contain a running list...

  3. Allegheny County Cemetery Outlines

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Outlines of public and private cemeteries greater than one acre in size. Areas were delineated following a generalized line along the outside edge of the area....

  4. Durham County Demographic Profile

    City and County of Durham, North Carolina — (a) Includes persons reporting only one race.(b) Hispanics may be of any race, so also are included in applicable race categories. D: Suppressed to avoid disclosure...

  5. County Political Boundaries (National)

    Department of Transportation — County boundaries with political limit - boundaries extending into the ocean (NTAD 2015). The TIGER/Line shapefiles and related database files (.dbf) are an extract...

  6. Minnesota County Boundaries

    Minnesota Department of Natural Resources — Minnesota county boundaries derived from a combination of 1:24,000 scale PLS lines, 1:100,000 scale TIGER, 1:100,000 scale DLG, and 1:24,000 scale hydrography...

  7. Allegheny County Dog Licenses

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — A list of dog license dates, dog breeds, and dog name by zip code. Currently this dataset does not include City of Pittsburgh dogs.

  8. Estimating Snow Budget of Karaj Dam Reservoir

    Manijeh G. Tali


    Full Text Available Problem statement: Most of the cold period precipitation of Karaj Basin falls in the form of snow. This snow and its run off are important to the dam and the local needs such as agriculture and the drinking water of Tehran. But due to the scarcity and in some elevations the lack of weather stations, measuring this snow cover and its run off is difficult. We have decided to estimate the amount of this snow cover by using surrogate methods such as satellite images of MODIS and temperature thresholds. Approach: To estimate the snow water budget of the Karaj Dam Reservoir Basin, first a temperature threshold of 3° Celsius was defined according to the analysis of daily temperature and precipitation values of Nesa station during 1960-2000. The elevation of this temperature was as low as 1590 m in February and 5734 m in August. During each month the melting snow was computed over the area between 3 and zero degrees Celsius and precipitation below zero degrees was considered as permanent snow cover. The precipitation of areas above 3° was computed as rain. Using this temperature threshold and the DEM map of the basin we estimated the snow cover and snow melt water of the basin. The snow cover area on the MODIS images was estimated and compared with that computed from temperature threshold. Both methods gave relatively similar results. At the end the snow melt water of the whole cold period was calculated and added up to estimate the total snow water budget. Results: The results showed that during the study months most (67.7% of the precipitation comes in the form of snow. And most of this snow (97.5% melts during months March and onward. Its monthly distributions are 3.8% in March, 22.7% in April and 71% in May. The total snow water entering the dam was about 181.73 million cubic meters. Conclusion: The comparison of the results from temperature thresholds with the MODIS images snow cover showed very little and negligible discrepancy. Therefore, this

  9. Dam overtopping risk using probabilistic concepts – Case study: The Meijaran Dam, Iran

    Ehsan Goodarzi


    Full Text Available Hydrologic risk assessment and uncertainty analysis by mathematical and statistical methods provide useful information for decision makers. This study presents the application of risk and uncertainty analysis to dam overtopping due to various inflows and wind speeds for the Meijaran Dam in the north of Iran. The procedure includes univariate flood and wind speed frequency analyses, reservoir routing, and integration of wind set-up and run-up to calculate the reservoir water elevation. Afterwards, the probability of overtopping was assessed by applying two uncertainty analysis methods (Monte Carlo simulation and Latin hypercube sampling, and considering the quantile of flood peak discharge, initial depth of water in the reservoir, and spillway discharge coefficient as uncertain variables. The results revealed that rising water level in the reservoir is the most important factor in overtopping risk analysis and that wind speed also has a considerable impact on reservoirs that are placed in windy areas.

  10. Fosfortab fra det dyrkede areal til Stevning Dam, Hindemaj og Haderslev Dam

    Andersen, Hans Estrup; Heckrath, Goswin; Thodsen, Hans;

    Størrelsen af dyrkningsbidraget til søerne i Haderslev Dam-systemet er vurderet med to forskellige metoder til at udgøre ca. 42 % af den samlede tilførsel. En risikokortlægning med det nye, danske P-indeks viser, at i alt 15 % af det dyrkede areal er i højrisiko mht. fosfortab. P-indeks-kortlægni......Størrelsen af dyrkningsbidraget til søerne i Haderslev Dam-systemet er vurderet med to forskellige metoder til at udgøre ca. 42 % af den samlede tilførsel. En risikokortlægning med det nye, danske P-indeks viser, at i alt 15 % af det dyrkede areal er i højrisiko mht. fosfortab. P...

  11. Evaluating temporal changes in hydraulic conductivities near karst-terrain dams: Dokan Dam (Kurdistan-Iraq)

    Dafny, Elad; Tawfeeq, Kochar Jamal; Ghabraie, Kazem


    Dam sites provide an outstanding opportunity to explore dynamic changes in the groundwater flow regime because of the high hydraulic gradient rapidly induced in their surroundings. This paper investigates the temporal changes of the hydraulic conductivities of the rocks and engineered structures via a thorough analysis of hydrological data collected at the Dokam Dam, Iraq, and a numerical model that simulates the Darcian component of the seepage. Analysis of the data indicates increased seepage with time and suggests that the hydraulic conductivity of the rocks increased as the conductivity of the grout curtain decreased. Conductivity changes on the order of 10-8 m/s, in a 20-yr period were quantified using the numerical analysis. It is postulated that the changes in hydraulic properties in the vicinity of Dokan Dam are due to suspension of fine materials, interbedded in small fissures in the rocks, and re-settlement of these materials along the curtain. Consequently, the importance of the grout curtain to minimize the downstream seepage, not only as a result of the conductivity contrast with the rocks, but also as a barrier to suspended clay sediments, is demonstrated. The numerical analysis also helped us to estimate the proportion of the disconnected karstic conduit flow to the overall flow.

  12. Estimates o the risks associated with dam failure

    Ayyaswamy, P.; Hauss, B.; Hseih, T.; Moscati, A.; Hicks, T.E.; Okrent, D.


    The probabilities and potential consequences of dam failure in California, primarily due to large earthquakes, was estimated, taking as examples eleven dams having a relatively large population downstream. Mortalities in the event of dam failure range from 11,000 to 260,000, while damage to property may be as high as $720 million. It was assumed that an intensity IX or X earthquake (on the Modified Mercalli Scale) would be sufficient to completely fail earthen dams. Predictions of dam failure were based on the recurrence times of such earthquakes. For the dams studied, the recurrence intervals for an intensity IX earthquake varied between 20 and 800 years; for an intensity X between 50 and 30,000 years. For the Lake Chabot and San Pablo dams (respectively 20, 30 years recurrent earthquake times for a intensity X) the associated consequences are: 34,000 (Lake Chabot) and 30,000 (San Pablo) people killed; damage $140 million and $77 million. Evaculation was found to ameliorate the consequences slightly in most cases because of the short time available. Calculations are based on demography, and assume 10 foot floodwaters will drown all in their path and destroy all one-unit homes in the flood area. Damage estimates reflect losses incurred by structural damage to buildings and do not include loss of income. Hence the economic impact is probably understated.

  13. Environmental and dam effects on cannibalism in Wistar rat litters

    Graziela Tarôco


    Full Text Available The factors related to cannibalistic behavior of dams in a Wistar rat colony are identified and analyzed. The maternal genetic effects were tested as a random effect by the method of generalized linear models. The season at parturition, the dam´s age at parturition and the density of the room at parturition were tested as fixed effects, whereas the litter size at birth was tested as a co-variable. The genetic effect of the dam was significant for the number of cannibalized pups. Although the season at parturition, the dam´s age and room density on the day of parturition were not individually significant (p > 0.05, most of the interactions between the variation sources were significant (p < 0.05. Cannibalism occurred mostly in dams aged over 241 days, with parturition during spring. So that occurrences of cannibalism could be avoided, dams with the smallest number of cannibalized pups should be selected, coupled to dams younger than 241 days, breeding during spring. The above strategies may reduce the number of couples in the vivarium and increase their production efficiency.

  14. Responses of riparian reptile communities to damming and urbanization

    Hunt, Stephanie D.; Guzy, Jacquelyn C.; Price, Steven J.; Halstead, Brian J.; Eskew, Evan A.; Dorcas, Michael E.


    Various anthropogenic pressures, including habitat loss, threaten reptile populations worldwide. Riparian zones are critical habitat for many reptile species, but these habitats are also frequently modified by anthropogenic activities. Our study investigated the effects of two riparian habitat modifications-damming and urbanization-on overall and species-specific reptile occupancy patterns. We used time-constrained search techniques to compile encounter histories for 28 reptile species at 21 different sites along the Broad and Pacolet Rivers of South Carolina. Using a hierarchical Bayesian analysis, we modeled reptile occupancy responses to a site's distance upstream from dam, distance downstream from dam, and percent urban land use. The mean occupancy response by the reptile community indicated that reptile occupancy and species richness were maximized when sites were farther upstream from dams. Species-specific occupancy estimates showed a similar trend of lower occupancy immediately upstream from dams. Although the mean occupancy response of the reptile community was positively related to distance downstream from dams, the occupancy response to distance downstream varied among species. Percent urban land use had little effect on the occupancy response of the reptile community or individual species. Our results indicate that the conditions of impoundments and subsequent degradation of the riparian zones upstream from dams may not provide suitable habitat for a number of reptile species.

  15. The collapse of the Sella Zerbino gravity dam.

    Petaccia, G; Lai, C G; Milazzo, C; Natale, L


    When a severe flood wave completely filled the Ortiglieto reservoir on August 13, 1935, the 14 m high "Sella Zerbino" secondary dam failed catastrophically causing > 100 casualties. Both of the dams, Sella Zerbino-Zerbino Saddle and Bric Zerbino-Zerbino Peak (Fig. 1) were overtopped but only the Sella Zerbino failed whereas the main barrage did not suffer any damage. The lawsuit that followed this tragic event ended with a full acquittal of the dam's designers since the plaintiff experts succeeded in demonstrating that the collapse was due to an extreme rainfall storm of unpredictable intensity. The case was then officially closed and still today the failure of the Sella Zerbino dam is attributed to the unpredictable hydrological event. Recently, Natale and Petaccia (2013) re-examined the case assessing the capacity of the flood spillways which equipped the Bric Zerbino dam. This paper thoroughly reviews the mechanics of the collapse of the Sella Zerbino dam focusing on the stability of the structure. The water pressure underneath the dam and the poor quality of the foundation rock is believed to have played a major role in the sequence of events that ended in the collapse of the barrage.

  16. Characterization of colostrum from dams of BLV endemic dairy herds.

    Gutiérrez, Gerónimo; Lomonaco, Marina; Alvarez, Irene; Fernandez, Fernando; Trono, Karina


    Bovine Leukemia Virus (BLV) is endemic in Argentina, where the individual prevalence is higher than 80% in dairy farms. The aim of this work was to find preliminary evidence to know if the high level of infection of the dam would implicate a higher challenge to her own offspring. We collected 65 sets of samples consisting of dam's blood and colostrum from two heavily infected dairy farms, and investigated the correlation between the dam's blood proviral load and the presence of provirus in colostrum. We also described the dual antibody/provirus profile in the colostrum. Provirus was detected in 69.23% of the colostrum samples, mostly from dams with a high proviral load, 36/45 (80%). Colostrum proviral load was significantly higher in dams with high blood proviral load (pcolostrum samples all along the antibody distribution, even in those with a low amount of antibodies. These results show that even when high blood proviral load dams offer higher levels of infected cells to their offspring through colostrum they also offer higher levels of protection of antibodies. On the contrary, low blood proviral load dams also offer infected cells but a poor content of antibodies, suggesting that these animals could play an important role in the epidemiological cycle of transmission.

  17. Safety of small and medium dams in permafrost regions

    Rudolf V.Zhang; Sergey A.Velikin


    Safe operation and performance of dams is one of the key issues in permafrost regions. At present, the existing dams are 40 45 years old and they are reaching their design life limit. Intensive geocryological processes (thermokarst, thermal erosion, frost heaving, suffosion, concentrated seepage along the voids left by melt ice and others) begin to develop at the early stages of construction. These processes are even more intensive under severe climatic conditions of the permafrost zone due to the large thermal and moisture gradients and the resulting complex thermal stress strain state in the structures. Determining safety criteria is a critical and difficult task in dam safety management. The existing procedures need to be continuously refined and improved depending on dam importance class. Some researchers recommend introducing process development criteria (stability, destabilization, and extremality) for more objective assessment of dam safety, in addition to the existing two condition criteria. In other words, they call for a multi factor dam environment interaction system. A case study of safety declaration for an existing dam is presented.

  18. Deformation reinforcement theory and its application to high arch dams


    In this paper,the deformation reinforcement theory(DRT) proposed by the authors is elaborated with a new definition of instability that an elasto-plastic structure is not stable if it cannot satisfy simultaneously equilibrium condition,kinematical admissibility and constitutive equations under the prescribed loading.Starting from the definition,a proof is established to the principle of minimum plastic complementary energy for failured structures.It is revealed that the principle of mini-mum plastic complementary energy results in relaxed constitutive equations,especially,yield conditions.It is demonstrated with case studies that many key issues in arch dam design,e.g.,global stability,dam-toe reinforcement,dam-toe cracking,dam-abut-ment reinforcement,can be well solved within the framework of the deformation reinforcement theory.The structural global stability can be described by the curve of the plastic complementary energy vs overloading factor.The unbalanced-forces obtained by elasto-plastic FEM can be used as the basis of analysis of global stability,dam-heel cracking,dam-toe anchorage and reinforcement of faults of high arch dams and their foundations.

  19. Minidoka Dam Wildlife Impact Assessment: Final Report.

    Martin, Robert C.; Meuleman, G. Allyn


    A wildlife impact assessment has been developed for the US Bureau of Reclamation's Minidoka Dam and Reservoir in south central Idaho. This assessment was conducted to fulfill requirements of the Fish and Wildlife Program. Specific objectives of this study included the following: select target wildlife species, and identify their current status and management goals; estimate the net effects on target wildlife species resulting from hydroelectric development and operation; recommend protection, mitigation, and enhancement goals for target wildlife species affected by hydroelectric development and operation; and consult and coordinate impact assessment activities with the Northwest Power Planning Council, Bonneville Power Administration, US Bureau of Reclamation, Bureau of Land Management, Shoshone-Bannock Tribes, US Fish and Wildlife Service, Pacific Northwest Utilities Conference Committee, and other entities expressing interest in the project. 62 refs., 2 figs., 11 tabs.

  20. Erosion monitoring along the Coosa River below Logan Martin Dam near Vincent, Alabama, using terrestrial light detection and ranging (T-LiDAR) technology

    Kimbrow, Dustin R.; Lee, Kathryn G.


    Alabama Power operates a series of dams on the Coosa River in east central Alabama. These dams form six reservoirs that provide power generation, flood control, recreation, economic opportunity, and fish and wildlife habitats to the region. The Logan Martin Reservoir is located approximately 45 kilometers east of Birmingham and borders Saint Clair and Talladega Counties. Discharges below the reservoir are controlled by power generation at Logan Martin Dam, and there has been an ongoing concern about the stability of the streambanks downstream of the dam. The U.S. Geological Survey, in cooperation with Alabama Power conducted a scientific investigation of the geomorphic conditions of a 115-meter length of streambank along the Coosa River by using tripod-mounted terrestrial light detection and ranging technology. Two surveys were conducted before and after the winter flood season of 2010 to determine the extent and magnitude of geomorphic change. A comparison of the terrestrial light detection and ranging datasets indicated that approximately 40 cubic meters of material had been eroded from the upstream section of the study area. The terrestrial light detection and ranging data included in this report consist of electronic point cloud files containing several million georeferenced data points, as well as a surface model measuring changes between scans.

  1. Risk Perception Analysis Related To Existing Dams In Italy

    Solimene, Pellegrino


    In the first part of this work, the progress of Italian National Rules about dams design, construction and operation are presented to highlight the strong connection existing between the promulgation of new decrees, as a consequence of a dam accidents, and the necessity to prevent further loss of lives and goods downstream. Following the Gleno Dam failure (1923), a special Ministerial Committee wrote out the first Regulations and made the proposal to establish, within the High Council of Public Works, a special department that become soon the "Dam Service", with the tasks of control and supervision about construction and operation phases of the dams and their reservoirs. A different definition of tasks and the structure of Dam Service were provided in accordance with law n° 183/1989, which transferred all the technical services to the Office of the Prime Minister; the aim was to join the Dam Office with the Department for National Technical Services, with the objective of increasing the knowledge of the territory and promoting the study on flood propagation downstream in case of operations on bottom outlet or hypothetical dam-break. In fact, population living downstream is not ready to accept any amount of risk because has not a good knowledge of the efforts of experts involved in dam safety, both from the operators and from the safety Authority. So it's important to optimize all the activities usually performed in a dam safety program and improve the emergency planning as a response to people's primary needs and feeling about safety from Civil Protection Authority. In the second part of the work, a definition of risk is provided as the relationship existing between probability of occurrence and loss, setting out the range within to plan for prevention (risk mitigation), thanks to the qualitative assessment of the minimum safety level that is suited to assign funds to plan for Civil Protection (loss mitigation). The basic meaning of the reliability of a zoned

  2. On monolithic stability and reinforcement analysis of high arch dams


    Monolithic stability safety and reinforcement based on monolithic stability are very important for arch dam design.In this paper,the issue is addressed based on deformation reinforcement theory.In this approach,plastic complementary energy norm can be taken as safety Index for monolithic stability.According to deformation reinforcement theory,the areas where unbalanced force exists require reinforcement,and the required reinforcement forces are just the unbalanced forces with opposite direction.Results show that areas with unbalanced force mainly concentrate in dam-toes,dam-heels and faults.

  3. River turbidity and sediment loads during dam removal

    Warrick, Jonathan A.; Duda, Jeffrey J.; Magirl, Christopher S.; Curran, Chris A.


    Dam decommissioning has become an important means for removing unsafe or obsolete dams and for restoring natural fluvial processes, including discharge regimes, sediment transport, and ecosystem connectivity [Doyle et al., 2003]. The largest dam-removal project in history began in September 2011 on the Elwha River of Washington State (Figure 1a). The project, which aims to restore the river ecosystem and increase imperiled salmon populations that once thrived there, provides a unique opportunity to better understand the implications of large-scale river restoration.

  4. Seismic rehabilitation and analysis of Chaohe earth dam

    Lei Fu; Xiangwu Zeng


    Stability of earth dams during earthquakes has been a major concern for geotechnical engineers in seismic active regions. Liquefaction induced slope failure occurred at the upstream slope of a major earth dam in the suburb of Beijing, China, during the 1976 Tangshan Earthquake. The gravelly soil with loose initial condition liquefied under relatively small ground vibration. In recent years, a major seismic rehabilitation project was carried out on a similar earth dam nearby using dumped quarry stone. Seismic stability analysis was carried out using model test, finite element simulation, and pseudostatic slope stability program after taking into account the influence of excess pore pressure.

  5. Accuracy Analysis of a Dam Model from Drone Surveys

    Elena Ridolfi; Giulia Buffi; Sara Venturi; Piergiorgio Manciola


    This paper investigates the accuracy of models obtained by drone surveys. To this end, this work analyzes how the placement of ground control points (GCPs) used to georeference the dense point cloud of a dam affects the resulting three-dimensional (3D) model. Images of a double arch masonry dam upstream face are acquired from drone survey and used to build the 3D model of the dam for vulnerability analysis purposes. However, there still remained the issue of understanding the real impact of a...

  6. Geodetic and Non-Geodetic Methods for Deformation Monitoring of Rock-Fill Dams, a Case Study at Ataturk DAM

    Kalkan, Y.; Bilgi, S.


    Necessity to water is increasing day by day with respect to the World population, rising of living standards and destruction of nature. Water resources have to be controlled and supplied for agricultural uses, drinking and industrial purposes by the countries having limited water resources. This situation is also considerable for Turkey which has a location in the middle zone of World and having limited water sources. Dams are among the most important engineering structures which are used for these purposes. However, the functioning life of dams is as important as the investment and construction. Nevertheless, in order to provide safety of human life living around, well planned monitoring is essential for dams. Deformation measurements have an important status among various engineering surveying. Considering the time and labor consumed by long-term measurements, processing and analysis of measured data, importance of the horizontal and vertical small structural motions at regular intervals could be comprehended. Ataturk Dam in Turkey is the 6th largest dam of world considering the filling volume of embankment. Deformation of Ataturk Dam is being monitoring yearly since 2006 by Istanbul Technical University Department of Geomatics Engineering. We apply both GPS and conventional techniques. In this study, we present the result of radial deformations on Ataturk Dam between 2006 and 2010. The results show significant horizontal movements among the 72% of object points. Maximum movement is found as 14.12 cm (with a radial component of 14.08 cm) in 4.5 years.

  7. The Effects of the Anti-Dam Movement on the Environmental Protection in American West



    This paper examines the far - reaching influence of anti - dam movement on the protection of environment in the second half of the 20th century in American West. It first introduces the historical background of dams built along the Colorado Biver - the most important river in the West, especially the construction of Hoover Dam and Glen Canyon Dam. Then, the criticism of dams on the Colorado is examined with the emphasis on the anti - dam movement resulting from the awareness of the negative ecological impacts on the Colorado. In the conclusion, the author demonstrates the unparallel historical significance of the anti -dam movement in the en-vironmentalism in developing the American West.

  8. An Archaeological Survey of the Galisteo Dam and Reservoir Area Santa Fe County, New Mexico.


    Geologic-climate dating in the West. American Antiquity 20: 317-355. Betancourt, Julio L. and Thomas R. Van Devender " 1981 Holocene vegetation in Cuaco...Prehistoric Southwestern turquoise industry. El Palacto 79(1): 33-51. Thoms, Alston Vern 1977 A preliminary projectile point typology for the southern

  9. 75 FR 61417 - South River Watershed Dam No. 10A, Augusta County, VA


    ... project. The project purpose is continued flood prevention. The planned works of improvement include... Protection and Flood Prevention, and is subject to the provisions of Executive Order 12372, which...

  10. Water-quality data from an earthen dam site in southern Westchester County, New York, 2015

    Chu, Anthony; Noll, Michael L.


    The U.S. Geological Survey, in cooperation with the New York City Department of Environmental Protection, sampled 37 sites in the reservoir area for nutrients, major ions, metals, pesticides and their degradates, volatile organic compounds, temperature, pH, and specific conductance during fall 2015. Data collection was done to characterize the local groundwater-flow system and identify potential sources of seeps from the southern embankment at the Hillview Reservoir. Water-quality samples were collected in accordance with standard U.S. Geological Survey methods at 37 sites in and adjacent to Hillview Reservoir. These 37 sites were sampled to determine (1) baseline water-quality conditions of the saturated, low-permeability sediments that compose the earthen embankment that surrounds the reservoir, (2) water-quality conditions in the southwestern part of the study area in relation to the seeps on the embankment, and (3) temporal variation of water-quality conditions between 2006 and 2015 (not included in this report). The physical parameters and the results of the water-quality analysis from the 37 sites are included in this report and can be downloaded from the U.S. Geological Survey National Water Information System website.

  11. Archaeological Reconnaissance of the Oliver Lock and Dam Project Area, Tuscaloosa County, Alabama. Phase I.


    settlements in the river channel constitute a well developed riverine- horticultural settlement pattern. Unlike the river channel levees, few systematic...a kind of therapy (Henry Rice, personal communica- t ion) . The now demolished remains of the hospital overseer’s house are identified in the state...elevated locations throughout the nineteenth and twentieth centuries. During the development of intensive horticulture in the Southeast, populations

  12. A Cultural Resources Survey of the Whitlow Ranch Dam and Reservoir Area, Eastern Pinal County, Arizona,


    actually common in areas on the periphery of the Hohokam world; they occur in the Altar drainage of northern Mexico and the Papagueria (Stacey 1974...The excavation of Los Muertos and neighboring ruins in the Salt River Valley, Southern Arizona. Papers of the Peabody Museum of American Archaeology

  13. 75 FR 24965 - Mormon Island Auxiliary Dam (MIAD) Modification Project, Sacramento and El Dorado Counties, CA


    ... safety, growth inducement, noise, environmental justice, and Indian trust assets. There is the potential... foundation and installation of filters and drains to reduce static (seepage and piping) risks. Creation of up...

  14. Intensive Survey of Two Rivers Dam and Reservoir Project, Chaves County, New Mexico.


    Northern Texas Pan- handle archeological assemblage. Unpublished MA thesis,Department of Antropology , Texas Tech University. " Bandy, Philip A., S. Alan...Consul- tants, Inc., Dallas. Basehart, Harry W. 1973 Mescalero Apacue subsistence patterns. In Technical Manual : 1973 survey of the Tularosa Basin, pp...settlement of southern New Mexico. In Technical Manual : 1973 survey of the Tularosa Basid, pp. 182-186.l Human Systems Research, Inc. Kelley, Narcissa

  15. Lessons learned from Wenchuan earthquake for seismic safety of large dams

    Chen Houqun


    This paper describes some special features of the Wenchuan earthquake that affected dam safety. Damage and performance of dams, primarily for four dams over 100 m high located in the affected earthquake area, are briefly described.Lessons learned related to dam safety from this devastating earthquake are preliminarily drawn. As the seismic safety of high dams during strong earthquakes has gained more attention around the world, some critical issues related to dam construction in China are considered and extensively discussed. Questions such as "Why is dam construction necessary in earthquake prone countries such as China?", "Can we accurately evaluate the seismic safety of high dams in China?", "Did reservoir impounding of the Zipingpu and Three Gorges Projects trigger the Wenchuan Earthquake in some way?" and "What is the strategic priority of dam safety for large dams in China?" are discussed. Finally, the corresponding tactics with response to the challenge are suggested and recent preliminary progress mainly achieved in IWHR is briefly introduced.

  16. Dam design can impede adaptive management of environmental flows: a case study from the Opuha Dam, New Zealand.

    Lessard, JoAnna; Hicks, D Murray; Snelder, Ton H; Arscott, David B; Larned, Scott T; Booker, Doug; Suren, Alastair M


    The Opuha Dam was designed for water storage, hydropower, and to augment summer low flows. Following its commissioning in 1999, algal blooms (dominated first by Phormidium and later Didymosphenia geminata) downstream of the dam were attributed to the reduced frequency and magnitude of high-flow events. In this study, we used a 20-year monitoring dataset to quantify changes associated with the dam. We also studied the effectiveness of flushing flows to remove periphyton from the river bed. Following the completion of the dam, daily maximum flows downstream have exceeded 100 m(3) s(-1) only three times; two of these floods exceeded the pre-dam mean annual flood of 203 m(3) s(-1) (compared to 19 times >100 m(3) s(-1) and 6 times >203 m(3) s(-1) in the 8 years of record before the dam). Other changes downstream included increases in water temperature, bed armoring, frequency of algal blooms, and changes to the aquatic invertebrate community. Seven experimental flushing flows resulted in limited periphyton reductions. Flood wave attenuation, bed armoring, and a shortage of surface sand and gravel, likely limited the effectiveness of these moderate floods. Floods similar to pre-dam levels may be effective for control of periphyton downstream; however, flushing flows of that magnitude are not possible with the existing dam infrastructure. These results highlight the need for dams to be planned and built with the capacity to provide the natural range of flows for adaptive management, particularly high flows.

  17. National Dam Inspection Program. Converse Lake Dam (CT 00044). Connecticut Coastal Basin, Greenwich, Connecticut. Phase I Inspection Report.


    Rosenstiel Estate. S-: f. Operator - Mr. Fredrick Jansen (Estate Superintendent) (203)661-9168 -’ .g. Purpose of Dam - Recreational - The dam was originally...cut from the downstream slope of the dam by Mr. Jansen , the estate superintendent. N 4.3 MAINTENANCE OF OPERATING FACILITIES ft There is no known...a bre in the blooi’pn.Ts cn o esosn ,71 ncut drainn theo lake or e;: v.atng7 oac C" t J C n o -2 alor A’J 1 Ian toWld that a considerable flow

  18. Route-Specific Passage Proportions and Survival Rates for Fish Passing through John Day Dam, The Dalles Dam, and Bonneville Dam in 2010 and 2011

    Ploskey, Gene R.; Weiland, Mark A.; Carlson, Thomas J.


    This report fulfills a request of the U.S. Army Engineer District, Portland, Oregon, to produce an interim report of estimates of route-specific fish passage proportions and survival rates for lower Columbia River dams in 2010 and 2011. The estimates are needed to update the Compass Model for the Columbia River Treaty and the new Biological Opinion before detail technical reports are published in late 2012. This report tabulates route-specific fish-passage proportions and survival rates for steelhead and Chinook salmon smolts passing through various sampled routes at John Day Dam, The Dalles Dam, and Bonneville Dam in 2010 and 2011. Results were compiled from analyses of data acquired in spring 2010 and 2011 studies that were specifically designed to estimate dam-passage and forebay-to-tailrace survival rates, travel time metrics, and spill passage efficiency, as stipulated by the 2008 Federal Columbia River Power System Biological Opinion and the Columbia Basin Fish Accords. The study designs allowed for estimation of route-specific fish passage proportions and survival rates as well as estimation of forebay-passage survival, all of which are summarized herein.

  19. Intelligent compaction theory of high roller compacted concrete dam

    Liu Donghai


    The concept and realization process of intelligent compaction for the construction of high roller compacted concrete dam were presented, as well as the theory of monitoring and intelligent feedback control. Based on the real-time analysis of the compaction index, a multiple regression model of the dam compactness was established and a realime estimation method of compaction quality for the entire work area of roller compacted concrete dam was proposed finally. The adaptive adjustment of the roiling process parameters was achieved, with the speed, the exciting force, the roller pass and the compaction thickness meeting the standards during the whole construction process. As a result, the compaction quality and construction efficiency can be improved. The research provides a new way for the construction quality control of roller compacted concrete dam.

  20. Study on Rock Bolt Reinforcement for a Gravity Dam Foundation

    Chen, S. H.; Yang, Z. M.; Wang, W. M.; Shahrour, I.


    In this article, the rock bolt reinforcement mechanism is discussed, and the gravity method as well as the finite element method for the bolted rock is presented. These methods are applied to study the gravity dam foundation of the Xiaoxi Hydropower Project, which is influenced by the presence of a large fault with a cracked zone over 180 m wide. Rock bolt reinforcement was used to improve the stability of the dam foundation, and the reinforcement parameters were determined from a semi-empirical equation controlled by in situ test. The stability analysis was conducted using the above methods, and the improvement in terms of deformation and stress as well as stability of the dam foundation due to the reinforcement is assessed. Rock bolt reinforcement was completed successfully, and the dam started normal operations in January 2008.

  1. Parallel computation of seismic analysis of high arch dam

    Chen Houqun; Ma Huaifa; Tu Jin; Cheng Guangqing; Tang Juzhen


    Parallel computation programs are developed for three-dimensional meso-mechanics analysis of fully-graded dam concrete and seismic response analysis of high arch dams (ADs), based on the Parallel Finite Element Program Generator (PFEPG). The computational algorithms of the numerical simulation of the meso-structure of concrete specimens were studied. Taking into account damage evolution, static preload, strain rate effect, and the heterogeneity of the meso-structure of dam concrete, the fracture processes of damage evolution and configuration of the cracks can be directly simulated. In the seismic response analysis of ADs, all the following factors are involved, such as the nonlinear contact due to the opening and slipping of the contraction joints, energy dispersion of the far-field foundation, dynamic interactions of the dam-foundation-reservoir system, and the combining effects of seismic action with all static loads. The correctness, reliability and efficiency of the two parallel computational programs are verified with practical illustrations.

  2. Geologic and field investigations Dorris Dam Modoc National Wildlife Refuge

    US Fish and Wildlife Service, Department of the Interior — This report presents the results of a. geologic and field investigation of Dorris Dam performed to evaluate embankment and foundation conditions. The work included...

  3. Elwha Master Datafile - Elwha Dam Removal - Nearshore monitoring

    National Oceanic and Atmospheric Administration, Department of Commerce — Removal of two dams on the Elwha River, Washington will help restore natural sediment processes to the coastal environment near the river mouth. We are interested in...

  4. FULCRUM - A dam safety management and alert system

    Butt, Cameron; Greenaway, Graham [Knight Piesold Ltd., Vancouver, (Canada)


    Efficient management of instrumentation, monitoring and inspection data are the keys to safe performance and dam structure stability. This paper presented a data management system, FULCRUM, developed for dam safety management. FULCRUM is a secure web-based data management system which simplifies the process of data collection, processing and analysis of the information. The system was designed to organize and coordinate dam safety management requirements. Geotechnical instrumentation such as piezometers or inclinometers and operating data can be added to the database. Data from routine surveillance and engineering inspection can also be incorporated into the database. The system provides users with immediate access to historical and recent data. The integration of a GIS system allows for rapid assessment of the project site. Customisable alerting protocols can be set to identify and respond quickly to significant changes in operating conditions and potential impacts on dam safety.

  5. Will the Three Gorges Dam Stand The Test of Time?


    After successfully containing the biggest flood this century, the Three Gorges Dam,on the upper reaches of the Yangtze River in central China’s Hubei Province, has encountered another flood, that of public opinion:Will this dam be able to hold floods that are "once-in-10,000-years" or "once-in-1,000-years" or "once-in-a-century"? Should numerous hazards this year, including land and mudslides and mountain torrents,be blamed on accumulation of sediment caused by the construction of the Three Gorges Dam? To get answers to these questions,journalists from Xinhua News Agency interviewed Cao Guangjing, Board Chairman of the China Three Gorges Corp., the operator of the Three Gorges Dam.

  6. Water quality of Flag Boshielo Dam, Olifants River, South Africa ...


    Jul 24, 2013 ... the dam wall coincided with the end of a drought that lasted .... was estimated by dividing the mean annual runoff by the res- ...... column was approximately holomictic. There was ... Alternatively, internal N loss associated with.

  7. Greenhouse gas emissions from Brazil’s Amazonian hydroelectric dams

    Fearnside, Philip M.


    Tropical dams are often falsely portrayed as ‘clean’ emissions-free energy sources. The letter by de Faria et al (2015 Environ. Res. Lett. 10 124019) adds to evidence questioning this myth. Calculations are made for 18 dams that are planned or under construction in Brazilian Amazonia and show that emissions from storage hydroelectric dams would exceed those from electricity generation based on fossil fuels. Fossil fuels need not be the alternative, because Brazil has vast potential for wind and solar power as well as opportunities for energy conservation. Because dam-building is rapidly shifting to humid tropical areas, where emissions are higher than in other climatic zones, the impact of these emissions needs to be given proper weight in energy-policy decisions.

  8. Evaluating segregation in granular filters for earth dams

    Sutherland, K. [Cambridge Univ., Cambridge (United Kingdom); Grabinsky, M. [Toronto Univ., ON (Canada)


    This paper presented some case studies to illustrate the relationship between seepage problems encountered with earth dams and segregation of the dams' granular filters during construction. A literature review of segregation mechanisms was presented along with a laboratory investigation. The case studies showed that the current understanding of the impact of a given degree of segregation is relatively poor. The literature reveals that although segregation mechanisms are identified and analyzed, very few are likely to be predominant during earth dam construction. Laboratory studies show that a mathematical relationship can be established between the filter's grain size distribution curve and the potential degree of segregation. Therefore, a mathematical relationship can also be established with the potential for adverse dam performance. The authors proposed a field procedure which allows for the monitoring of segregation during construction by contractors and engineers. It also helps in deciding whether any segregated zones require replacement. 5 refs., 7 figs.


    Hui-Pang LIEN


    A new method to a slit dam for controlling the stony debris flow has been derived based on the mass conservation law of the stony debris flow passing through a slit dam and the laboratory experiment results.This new method is then combined with three primary efficiency expressions: the dimensionless sediment outflow ratio,the sediment concentration ratio,and the sediment storage rate to develop a simple module,with which the height and the spacing of the posts,as well as the total spacing of slit dam are determined.Furthermore,these expressions can also be applied to check those slit dams that have already been constructed with their effectiveness against various magnitudes of the debris flow. The comparison between these expressions and laboratory data is in reasonable agreement.

  10. Tailings dam-break flow - Analysis of sediment transport

    Aleixo, Rui; Altinakar, Mustafa


    A common solution to store mining debris is to build tailings dams near the mining site. These dams are usually built with local materials such as mining debris and are more vulnerable than concrete dams (Rico et al. 2008). of The tailings and the pond water generally contain heavy metals and various toxic chemicals used in ore extraction. Thus, the release of tailings due to a dam-break can have severe ecological consequences in the environment. A tailings dam-break has many similarities with a common dam-break flow. It is highly transient and can be severely descructive. However, a significant difference is that the released sediment-water mixture will behave as a non-Newtonian flow. Existing numerical models used to simulate dam-break flows do not represent correctly the non-Newtonian behavior of tailings under a dam-break flow and may lead to unrealistic and incorrect results. The need for experiments to extract both qualitative and quantitative information regarding these flows is therefore real and actual. The present paper explores an existing experimental data base presented in Aleixo et al. (2014a,b) to further characterize the sediment transport under conditions of a severe transient flow and to extract quantitative information regarding sediment flow rate, sediment velocity, sediment-sediment interactions a among others. Different features of the flow are also described and analyzed in detail. The analysis is made by means of imaging techniques such as Particle Image Velocimetry and Particle Tracking Velocimetry that allow extracting not only the velocity field but the Lagrangian description of the sediments as well. An analysis of the results is presented and the limitations of the presented experimental approach are discussed. References Rico, M., Benito, G., Salgueiro, AR, Diez-Herrero, A. and Pereira, H.G. (2008) Reported tailings dam failures: A review of the European incidents in the worldwide context , Journal of Hazardous Materials, 152, 846

  11. Riparian Vegetation Encroachment Ratios in rivers below large Dams

    Garcia de Jalón, Diego; Martínez-Fernández, Vanesa; González del Tánago, Marta


    Large Dams and reservoirs change the natural flow regime and consequently cause many alterations in riparian vegetation dynamics which may be assessed at different spatial and temporal scales. In Mediterranean regions flow regulation is frequently associated with irrigation. Regulated rivers with this purpose very often show reduced discharges during the wet season when the reservoir is being filled and increased discharges during the dry season when irrigation takes place. This type of regulation frequently promotes riparian vegetation growth as soil moisture levels are increased during summer when a natural drought would otherwise limit its growth. Additionally, flow regulation by large dams promotes the aging of late seral riparian vegetation reducing the frequency of flood disturbance and consequently, the potential recruitment of pioneer species. In this work we study the response of woody riparian vegetation to flow regulation by large dams in four rivers from Central Spain: Jarama, Manzanares, Guadalix and Alberche. The aim is to quantify the annual vegetation encroachment ratios and to develop a model to understand the main controlling factors, such as floodplain and channel traits; flow regulation intensity; type of regulation; present vegetation canopy; distance to the dam; and time since dam commissioning. A temporal comparison using aerial photographs from 1956, 1966, 1972, 1991, 2011 and 2014 was done in thirteen river reaches downstream from large dams, to evaluate their morphological evolution.. Floodplain dimensions and channel and riparian vegetation changes were assessed by comparing different pre-dam and post-dam conditions. Recent coloured photographs with 0.5 m spatial resolution and older black-and-white photographs at 1:33 000 spatial scale were supplied by the National Geographic Institute of Spain ( and the Statistical Institute ( from Madrid Community. Similar visual scales were used to cope

  12. Emergy evaluation perspectives of a multipurpose dam proposal in Korea.

    Kang, Daeseok; Park, Seok Soon


    The 'emergy' concept was used to evaluate the economy of Korea and the contributions of a multipurpose dam proposal to the real wealth of the Korean economy. Emergy is defined as the available energy of one kind previously used up directly and indirectly to make a product or service. The indices for Korea calculated from the emergy evaluation were close to those of developed countries. Even though its monetary balance of payments was negative in 1997, the economy of Korea showed positive balance in trade when exports and imports were expressed in emergy. The emergy evaluation showed that the Korean economy places a large stress on its environment. Water supply and generation of electricity were the most important contributions of the proposed dam in terms of emergy; 46.5 and 45.1% of the total benefit, respectively. Flood control contributed 8.4% of the total benefit. Major costs associated with the proposed dam were from sediments (33.2% of the total cost), construction services (22.8%), and social disruption of the region (21.6%). In terms of emergy, the ratio of benefits to costs of the proposed dam was 2.78 if sediments are not included, and 1.86 if sediments are included, which result in more benefits than costs in both cases. The benefit to cost ratio of the dam was larger than that of the current system (1.42) without the dam whether sediments are included in the total cost or not. The environmental stress of the proposed dam was considerably lower than that of the Korean economy, but the dam might increase stress on local environment.

  13. Liquefaction evaluation of dam foundation soils considering overlying structure

    Gang Wang; Xing Wei; Hanlong Liu


    The liquefaction analysis procedure conducted at a dam foundation associated with a layer of liquefiable sand is presented. In this case, the effects of the overlying dam and an embedded diaphragm wall on liquefaction potential of foundation soils are considered. The analysis follows the stress-based approach which compares the earthquake-induced cyclic stresses with the cyclic resistance of the soil, and the cyclic resistance of the sand under complex stress condition is the key issue. Compr...

  14. The Changing Political Dynamics of Dam Building on the Mekong

    Philip Hirsch


    Full Text Available This paper explores political dynamics surrounding dam building in the Mekong river basin, prior to, and following, the World Commission on Dams (WCD. Since the 1950s, dam building in the Mekong river basin has been enmeshed in a complex and shifting geopolitical and eco-political landscape. The broad geopolitical sweep of US hegemony, Cold War, regional rapprochement and the rise of China has been superimposed on eco-political shifts between modernist belief in progress as mastery over nature, concerns of global and national environmental movements over dams and their impacts, and a galvanised Mekong environmentalism. During the first decade of the 21st century, mainstream dams on the Lower Mekong have returned to the agenda after having almost disappeared in favour of tributary projects. The growing strength and assertiveness of regional economic players has fundamentally altered the context of energy demand, planning and investment. New sources of finance have relocated the points of political leverage. Environment has been mustered in favour of, as well as in opposition to, dam construction in the contexts of climate-change discourses, protected-area linkage with dam projects, and an industry push for sustainability protocols and certification. Despite the Mekong being one of its focal basins, WCD has not played a prominent role in this transformed arena, yet many of the social and environmental concerns, stakeholder-based processes and safeguard-oriented approaches to hydropower planning that WCD brought to the fore have persisted in the wider ethos of politics around dams in the region.

  15. Analysis of irreversible displacements of Daniel-Johnson dam

    Chouinard, L.; Zhao, W. [McGill Univ., Montreal, PQ (Canada); Lariviere, R. [Hydro-Quebec, Montreal, PQ (Canada); Cote, P. [Hydro-Quebec Production, Baie-Comeau, PQ (Canada)


    Irreversible displacements in dams are associated with alkali-aggregate reaction, creep, and other damaging effects that compromise the safety of dams. An identification of the nature of irreversible displacements is needed to predict the future behaviour of dams as well as to select appropriate remedial measures. This paper provided details of a principal component analysis (PCA) used to investigate swelling and small irreversible displacements observed at the Daniel-Johnson dam in Quebec. PCA is a multivariate statistical method that performs the analysis of correlations or covariances between several random variables simultaneously. Three datasets were used: (1) reservoir water level; (2) air temperature; and (3) pendulum displacements. Standard linear regression analyses (HST) were performed for each variable in order to eliminate outliers and replace missing values. The multivariate dataset was then used to perform PCA on the entire dataset as well as on subsets from the original data. Displacement data from pendulums were used in the multivariate statistical analysis in which each component was treated as a separate variable. The comparison of irreversible displacements of the dam from HST analysis and principal component analysis (PCA) indicated that results were consistent with the data. The PCA analysis identified dominant patterns of behaviour and detected 2 distinct components of irreversible deformations arising from creep and swelling of concrete. Results of the study showed that the PCA analysis led to a better understanding of the overall behaviour of the dam and of individual arches and buttresses. It was concluded that the PCA analysis method will help to improve dam safety in addition to more accurately predicting the future behaviour of dams. 6 refs., 2 tabs., 9 figs.

  16. Phytoplankton composition of Sazlidere Dam lake, Istanbul, Turkey

    Nese Yilmaz


    Full Text Available The phytoplankton composition of Sazlidere Dam lake was studied at 5 sampling sites between December 2003 - November 2005. A total of 67 taxa were recorded, representing Bacillariophyta (31, Chlorophyta (18, Cyanophyta (9, Chrysophyta (1, Cryptophyta (1, Dinophyta (3 and Euglenophyta (4. Bacillariophyta members constituted the dominant phytoplankton group in terms of species number. Nygaard’s compound index value and composition of phytoplankton indicate that the trophic state of Sazlidere Dam lake was changing from oligotrophic to mesotrophic.

  17. Water resource management in Japan: Forest management or dam reservoirs?

    Komatsu, Hikaru; Kume, Tomonori; Otsuki, Kyoichi


    Researchers and journalists in Japan recently proposed forest management as an alternative to dam reservoir development for water resource management. To examine the validity of the proposal, we compared the potential low-flow increase due to forest clearcutting with the increase due to dam reservoir development. Here, we focused on forest clearcutting as an end member among various types of forest management. We first analyzed runoff data for five catchments and found a positive correlation between annual precipitation and the low-flow increase due to deforestation. We then examined the increase in low-flow rates due to dam reservoir development (dQ(d)) using inflow and outflow data for 45 dam reservoirs across Japan. Using the relationship between annual precipitation and the low-flow increase due to deforestation, we estimated the potential increase in the low-flow rate for each dam reservoir watershed if forests in the watershed were clearcut (dQ(f)). Only 6 of the 45 samples satisfied dQ(f)>dQ(d), indicating that the potential increase in the low-flow rate due to forest clearcutting was less than the increase due to dam reservoir development in most cases. Twenty-five of the 45 samples satisfied dQ(f)<0.2 dQ(d), indicating the potential increase in the low-flow rate due to forest clearcutting was less than 20% of the increase due to dam reservoir development in more than half the cases. Therefore, forest management is far less effective for water resource management than dam reservoir development is in Japan.

  18. Snohomish County Biodiesel Project

    Chang, Terrill; Carveth, Deanna


    Snohomish County in western Washington State began converting its vehicle fleet to use a blend of biodiesel and petroleum diesel in 2005. As prices for biodiesel rose due to increased demand for this cleaner-burning fuel, Snohomish County looked to its farmers to grow this fuel locally. Suitable seed crops that can be crushed to extract oil for use as biodiesel feedstock include canola, mustard, and camelina. The residue, or mash, has high value as an animal feed. County farmers began with 52 acres of canola and mustard crops in 2006, increasing to 250 acres and 356 tons in 2008. In 2009, this number decreased to about 150 acres and 300 tons due to increased price for mustard seed.

  19. Seismic stability analysis of concrete gravity dams with penetrated cracks

    Shou-yan JIANG


    Full Text Available The seismic stability of a cracked dam was examined in this study. Geometric nonlinearity and large deformations, as well as the contact condition at the crack site, were taken into consideration. The location of penetrated cracks was first identified using the concrete plastic-damage model based on the nonlinear finite element method (FEM. Then, the hard contact algorithm was used to simulate the crack interaction in the normal direction, and the Coloumb friction model was used to simulate the crack interaction in the tangential direction. After verification of numerical models through a case study, the seismic stability of the Koyna Dam with two types of penetrated cracks is discussed in detail with different seismic peak accelerations, and the collapse processes of the cracked dam are also presented. The results show that the stability of the dam with two types of penetrated cracks can be ensured in an earthquake with a magnitude of the original Koyna earthquake, and the cracked dam has a large earthquake-resistant margin. The failure processes of the cracked dam in strong earthquakes can be divided into two stages: the sliding stage and the overturning stage. The sliding stage ends near the peak acceleration, and the top block slides a long distance along the crack before the collapse occurs. The maximum sliding displacement of the top block will decrease with an increasing friction coefficient at the crack site.

  20. Back analysis of mechanical parameters of roller compacted concrete dam


    In view of the diversity and complexity of mechanical parameters of roller compacted concrete dam(RCCD),the uniform design method,partial least-squares regression(PLS)and least squares support vector machine(LSSVM)were applied to the back analysis of RCCD with the use of the complex nonlinear relationship between dam mechanical parameters and dam displacements.During the process of back analysis,the initial samples of parameters were designed with uniform design method.Then,a transversely isotropic model of RCCD was established by MSC.Marc software.Through this model,training samples of LSSVM model could be obtained.And then,the complex nonlinear relationship between relative values of hydraulic components of dam displacements and mechanical parameters was established.Finally,actual relative values of dam hydraulic components are isolated from the measured data of dam displacements by using PLS.By inputting the isolated relative values into LSSVM model,the back analysis values of RCCD mechanical parameters can be obtained.The example analysis showed that mechanical parameters obtained by the above-mentioned back analysis method are reasonable,and the back analysis method is feasible.

  1. Assessment of some heavy elements in Galma dam, Zaria, Nigeria

    Butu, A.W


    Full Text Available The study was carried out to assess the levels of concentration and distribution of Pb, Cr, Fe, Cd, Co, Ni, Zn and Cu in Galma dam, Zaria, Nigeria which spanned to 35Km. The main source of data was the surface water from the lower and the upper regions of the dam. The samples were collected and prepared in the laboratory according to standard method, Atomic Absorption Spectrophotometry (AAS technique was used to analyze the data. The results showed concentration of Pb, Cr, Fe, Cd, Co, Zn and Cu at various levels and the concentration of Ni below detectable level. The results also showed the distribution of these elements at lower and upper regions of Galma dam. The enrichment of these heavy elements in the dam could be explained by the loading of the dam with debris and effluents produced by various human activities within the dam catchment area through overland and base flows and the release of elements from geologic processes. The concentration of Pb, Cr and Fe were observed to be slightly above NIS and WHO standards for drinking water. To minimize pollution of the reserviour, it is strongly recommended that there should be reduction in levels of some unhealthy practices such as indiscriminate discharge of effluents like, engine oil, lubricants, used batteries, electric bulbs/fluorescent tubes, electronic and electrical appliances and high level use of chemicals on the farms are recommended to be discouraged.

  2. Assessing Otter Presence In Dams: A Methodological Proposal

    Margarida Santos-Reis


    Full Text Available Standard otter survey methodology proposed by the IUCN Otter Specialist Group enables comparisons in present/absence data in different countries or in different regions. However, otter presence and distribution assessment in dry areas, such as the Mediterranean region, which are characterized by highly marked seasonal climate with intermittent water flow coupled with different types of habitats or systems such as dams, may gain from adjustment to the methodology. Pressure for dam building still occurs in these regions and the need for studies on ecological communities and species protection is increasing. Dams are very different from usual otter riverine habitat and we need to understand their influence on otter populations. Variation of dam location, reservoir characteristics and season will all influence spraint detectability. Environmental Impact Assessment Studies and ecological studies are frequently limited by both budget and time requiring field researchers to apply more efficient methodologies. Based on experience from studies conducted in Portugal we propose adjustments to the standard survey methodology (using spraints surveying otter presence in dams to be applied specifically to Mediterranean-type ecosystems. We define aspects to be considered regarding survey season, survey length and width, number and location of survey sites, among others. This paper will allow researchers to plan more effective field surveys based on standard otter survey methodology for the purpose of dam surveys, be that to detect otter presence/absence, a more in-depth comparative studies of otter presence, or simply improving the collecting of fresh spraints for molecular spraint analysis.

  3. The Social, Historical, and Institutional Contingencies of Dam Removal

    Magilligan, F. J.; Sneddon, C. S.; Fox, C. A.


    Environmental managers in the United States and elsewhere are increasingly perceiving dam removal as a critical tool for river restoration and enhancing watershed resilience. In New England, over 125 dams have been dismantled for ecological and economic rationales. A surprising number of these removals, including many that are ongoing, have generated heated conflicts between restoration proponents and local communities who value their dammed landscapes. Using a comparative case study approach, we examine the environmental conflict around efforts to remove six dams in New England. Each of these removal efforts followed quite different paths and resultant outcomes: successful removal, stalled removal, and failure despite seemingly favorable institutional conditions. Lengthy conflicts often transpired in instances where removals occurred, but these were successfully arbitrated by paying attention to local historical-geographical conditions conducive to removal and by brokering effective compromises between dam owners and the various local actors and stakeholders involved in the removal process. Yet our results across all cases suggest that these are necessary, but not sufficient conditions for restoration through dam removal since a similar set of conditions typified cases where removals are continuously stalled or completely halted. Scholars examining the intersection between ecological restoration and environmental politics should remain vigilant in seeking patterns and generalities across cases of environmental conflict in order to promote important biophysical goals, but must also remain open to the ways in which those goals are thwarted and shaped by conflicts that are deeply contingent on historical-geographical conditions and broader institutional networks of power and influence.

  4. Ecosystem Response During the Removal of the Elwha River Dams

    Pess, G. R.; McHenry, M.; Liermann, M. C.; Moses, R.; Denton, K.; McMillan, J.; Brenkman, S.; Duda, J.; Peters, R.; Anderson, J.; Quinn, T.


    Over the last century, the two dams blocked the upstream movement of anadromous fish to over 90% of the Elwha River watershed on the Olympic Peninsula of Washington State. These dams also restricted the downstream movement of sediment, wood, and other organic materials to the lower river and estuary. Populations of all Pacific salmon species and steelhead in the Elwha became critically low, habitat complexity decreased below the dams, and downstream coastal habitats became sediment starved. Simultaneous deconstruction of the two dams began in September 2011 was completed in September of 2014. The recent removal of the dams has been an opportunity to explore linkages among changes in sediment supply, salmonid populations, and ecosystem attributes. Preliminary findings focus on the delivery of millions of metric tonnes of sediment to the main river, its floodplain, and nearshore, the re-establishment of a natural wood delivery regime, the re-colonization of the upper watershed by anadromous fish, insights into functional relationships among salmonid populations and life history strategies, and the associated effects of all these elements on the aquatic and terrestrial foodwebs. This talk will provide an overview of the Elwha restoration project, and highlight recent changes observed during dam removal.

  5. The Social, Historical, and Institutional Contingencies of Dam Removal.

    Magilligan, F J; Sneddon, C S; Fox, C A


    Environmental managers in the United States and elsewhere are increasingly perceiving dam removal as a critical tool for river restoration and enhancing watershed resilience. In New England, over 125 dams have been dismantled for ecological and economic rationales. A surprising number of these removals, including many that are ongoing, have generated heated conflicts between restoration proponents and local communities who value their dammed landscapes. Using a comparative case study approach, we examine the environmental conflict around efforts to remove six dams in New England. Each of these removal efforts followed quite different paths and resultant outcomes: successful removal, stalled removal, and failure despite seemingly favorable institutional conditions. Lengthy conflicts often transpired in instances where removals occurred, but these were successfully arbitrated by paying attention to local historical-geographical conditions conducive to removal and by brokering effective compromises between dam owners and the various local actors and stakeholders involved in the removal process. Yet our results across all cases suggest that these are necessary, but not sufficient conditions for restoration through dam removal since a similar set of conditions typified cases where removals are continuously stalled or completely halted. Scholars examining the intersection between ecological restoration and environmental politics should remain vigilant in seeking patterns and generalities across cases of environmental conflict in order to promote important biophysical goals, but must also remain open to the ways in which those goals are thwarted and shaped by conflicts that are deeply contingent on historical-geographical conditions and broader institutional networks of power and influence.

  6. Effect of rubber dam on mercury exposure during amalgam removal.

    Kremers, L; Halbach, S; Willruth, H; Mehl, A; Welzl, G; Wack, F X; Hickel, R; Greim, H


    It was the aim of this investigation to treat 20 volunteers with maximally 5 amalgam fillings by the same comprehensive protocol in which all removals with (n = 8) and without (n = 12) rubber dam had been performed within a few months. Nine amalgam-related parameters indicated a close matching of both groups before removal. In the group without rubber dam, mercury (Hg) levels in plasma increased significantly above preremoval values at days 1 and 3 after removal; they decreased significantly below preremoval values at day 30 in the rubber-dam group and at day 100 in both groups. Excretion rates did not increase significantly in either group, but decreased significantly at day 100 in the protected group. Peak plasma-Hg was 0.6 ng/mL on average at day one and decreased with halftimes of 3 and 43 d in subjects protected by rubber dam. The results indicated that concentrations of total mercury in plasma responded rapidly to changes in the amalgam status and reflected the actual absorption most reliably. Notably, plasma-Hg levels were sensitive enough to detect a transient attenuation of the additional exposure by using rubber dam during the removal of only a few fillings. However, being small in magnitude and lasting 100 d at best, the rubber-dam effect had minor toxicological relevance.

  7. Elwha River dam removal-Rebirth of a river

    Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.


    After years of planning for the largest project of its kind, the Department of the Interior will begin removal of two dams on the Elwha River, Washington, in September 2011. For nearly 100 years, the Elwha and Glines Canyon Dams have disrupted natural processes, trapping sediment in the reservoirs and blocking fish migrations, which changed the ecology of the river downstream of the dams. All five Pacific salmon species and steelhead-historically present in large numbers-are locally extirpated or persist in critically low numbers. Upstream of the dams, more than 145 kilometers of pristine habitat, protected inside Olympic National Park, awaits the return of salmon populations. As the dams are removed during a 2-3 year project, some of the 19 million cubic meters of entrapped sediment will be carried downstream by the river in the largest controlled release of sediment into a river and marine waters in history. Understanding the changes to the river and coastal habitats, the fate of sediments, and the salmon recolonization of the Elwha River wilderness will provide useful information for society as future dam removals are considered.

  8. Allegheny County Cell Tower Points

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset portrays cell tower locations as points in Allegheny County. The dataset is based on outbuilding codes in the Property Assessment Parcel Database used...

  9. Valencia County E-911 Roads

    Earth Data Analysis Center, University of New Mexico — This data set contains a vector digital representation of all accessible roads in the county including interstate highways, State highways, county roads and some...

  10. Allegheny County Land Use Areas

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Allegheny County land use as ascribed to areas of land. The Land Use Feature Dataset contains photogrammetrically compiled information concerning vegetation and...

  11. Allegheny County Cell Tower Points

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset portrays cell tower locations as points in Allegheny County. The dataset is based on outbuilding codes in the Property Assessment Parcel Database used...

  12. Allegheny County Mortgage Foreclosure Records

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This data includes filings related to mortgage foreclosure in Allegheny County. The foreclosure process enables a lender to take possession of a property due to an...

  13. Allegheny County School District Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the school district boundaries within Allegheny County If viewing this description on the Western Pennsylvania Regional Data Center’s open...

  14. Allegheny County Land Use Areas

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Allegheny County land use as ascribed to areas of land. The Land Use Feature Dataset contains photogrammetrically compiled information concerning vegetation and...

  15. Allegheny County Commercial Vehicle Inspections

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset lists the locations and results of all commercial vehicle inspections performed by the Allegheny County Police Motor Carrier Safety Assistance Program...

  16. 2015 Lowndes County (GA) Lidar

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME: NOAA OCM Lidar for Lowndes County, GA with the option to Collect Lidar in Cook and Tift Counties, GA Lidar Data Acquisition and Processing Production Task...

  17. Sonoma County, CA, 2013 Lidar

    National Oceanic and Atmospheric Administration, Department of Commerce — Sonoma County Vegetation Mapping and LiDAR Consortium retained WSI to provide lidar and Orthophoto data and derived products in Sonoma County, CA. A classified LAS...

  18. Allegheny County Property Sale Transactions

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains data on all Real Property parcels that have sold since 2012 in Allegheny County, PA. Before doing any market analysis on property sales, check...

  19. Allegheny County Public Building Locations

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the locations of municipal facilities in Allegheny County. If viewing this description on the Western Pennsylvania Regional Data Center’s...

  20. Allegheny County Public Building Locations

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the locations of municipal facilities in Allegheny County. If viewing this description on the Western Pennsylvania Regional Data Center’s open...

  1. Curry County E-911 Roads

    Earth Data Analysis Center, University of New Mexico — Line attributes denoting all street centerlines in Curry County. Dataset includes all centerlines for all county maintained roads, all state and federal highways,and...

  2. Allegheny County Employee Salaries 2016

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Employee salaries are a regular Right to Know request the County receives. Here is the disclaimer language that is included with the dataset from the Open Records...


    Federal Emergency Management Agency, Department of Homeland Security — The Kent AOI consists of the costal portion of the county, and meshes up seamlessly with the Providence county AOI directly north. Ground Control is collected...


    Federal Emergency Management Agency, Department of Homeland Security — The Providence AOI consists of the costal portion of the county, and meshes up seamlessly with the Kent county AOI directly south. Ground Control is collected...

  5. Allegheny County Fast Food Establishments

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Allegheny County Health Department has generated this list of fast food restaurants by exporting all chain restaurants without an alcohol permit from the...

  6. Allegheny County School District Boundaries

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the school district boundaries within Allegheny County If viewing this description on the Western Pennsylvania Regional Data Center’s open...

  7. Allegheny County Poor Housing Conditions

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This estimate of the percent of distressed housing units in each Census Tract was prepared using data from the American Community Survey and the Allegheny County...

  8. Grant County E-911 Roads

    Earth Data Analysis Center, University of New Mexico — This data set contains a vector digital representation of all accessible roads in the county including interstate highways, State highways, county roads and city...

  9. Allegheny County Addressing Street Centerlines

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset shows the road centerlines in Allegheny County. If viewing this description on the Western Pennsylvania Regional Data Center’s open data portal...

  10. Allegheny County Summer Food Sites

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This data set shows the Summer Food Sites located within Allegheny County for children (18 years and younger) for breakfast and lunch during summer recess. OPEN...

  11. Allegheny County Jail Daily Census

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — A daily census of the inmates at the Allegheny County Jail (ACJ). Includes gender, race, age at booking, and current age. The records for each month contain a...

  12. Allegheny County Park Rangers Outreach

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Launched in June 2015, the Allegheny County Park Rangers program reached over 48,000 people in its first year. Park Rangers interact with residents of all ages and...

  13. Allegheny County Fatal Accidental Overdoses

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Fatal accidental overdose incidents in Allegheny County, denoting age, gender, race, drugs present, zip code of incident and zip code of residence. Zip code of...

  14. Dam failure analysis for the Lago de Matrullas Dam, Orocovis, Puerto Rico

    Torres-Sierra, Heriberto; Gómez-Fragoso, Julieta


    The U.S. Geological Survey, in cooperation with the Puerto Rico Electric Power Authority, completed a hydrologic and hydraulic study to assess the potential hazard to human life and property associated with the hypothetical failure of the Lago de Matrullas Dam, located within the headwaters of the Río Grande de Manatí. The hydrologic study yielded outflow hydrographs and peak discharges for Lago de Matrullas and other subbasins in the Río Grande de Manatí hydrographic basin for three extreme rainfall events: (1) a 6-hour probable maximum precipitation (PMP) event, (2) a 24-hour PMP event, and (3) a 100-year-recurrence, 24-hour rainfall event. The hydraulic study simulated the hypothetical dam failure of Lago de Matrullas using hypothetical flood hydrographs generated from the hydrologic study and selected dam breach parameters. The flood wave resulting from the failure was downstream-routed through the lower reaches of the Río Matrullas, the Río Toro Negro, and the Río Grande de Manatí for determination of water-surface profiles developed from the event-based hydrologic scenarios and “sunny day” (no precipitation) conditions. The Hydrologic Modeling System (HEC–HMS) and the River Analysis System (HEC–RAS) computer programs, developed by the Hydrologic Engineering Center (HEC) of the U.S. Army Corps of Engineers, were used for the hydrologic and hydraulic modeling, respectively. The flow routing in the hydraulic analyses was performed using the unsteady-state flow module available in the HEC–RAS model.

  15. Qu'Appelle River Dam, dam break analysis using advanced GIS tools for rapid modelling and inundation mapping

    Bonin, D. [Hatch Energy, Winnipeg, MB (Canada); Campbell, C. [Saskatchewan Watershed Authority, Moose Jaw, SK (Canada); Groeneveld, J. [Hatch Energy, Calgary, AB (Canada)


    The South Saskatchewan River Project (SSRP) comprises a multi-purpose reservoir that provides water for conservation and irrigation, flood control, power generation, recreation, and municipal and industrial water supply. In addition to the 64 m high Gardiner Dam, the 27 m high Qu'Appelle River Dam and the 22 km long Lake Diefenbaker Reservoir, the SSRP also includes ancillary works. The Qu'Appelle River valley extends for 458 km before connecting to the Assiniboine River. The valley is incised up to 90 m in depth and is a popular cottaging and recreational area with several major communities located in the flood plain. In the event of a breach of the Qu'Appelle Dam, the discharge will increase from a normal maximum discharge of under 60 m{sup 3} per second to over 50,000 m{sup 3} per second. The Saskatchewan Watershed Authority (SWA) is responsible for ensuring safe development of the Province's water resources, without affecting reservoir or lake operations, and preventing damage from flooding, erosion or land slides. It is in the process of developing Hazard Assessments and emergency preparedness plans for each of their dams in accordance with the Canadian Dam Safety Guidelines. Studies using GIS technology and the hydrodynamic routing model HEC-RAS have been completed to evaluate the potential inundation that may result in the event of failure of the Qu'Appelle River Dam. These studies involved the development of a breach parameter model using a breach data set revised to better reflect the Qu'Appelle River Dam; the development of a dam break model for the Qu'Appelle River Dam and downstream river and flood plain; and, the use of this model to simulate two potential dam failure scenarios for the Qu'Appelle River Dam, notably failure during passage of the PMF and failure during fair weather conditions. Inundation maps have been prepared for the downstream Qu'Appelle River valley for each of the above events. 3 refs., 4

  16. Dam that social networking: connecting South Africa's major dams to social media

    Butgereit, L


    Full Text Available , embarrassingly so, a marital bed. 2. Research Question and Methodology The data provided by the South African Department of Water Affairs is excellent and accurate [4, 5]. Unfortunately, the majority of South Africans are not aware of the data which... provides a nice fly-in approach to viewing the Vaal Dam. The data provided in the description field of the KML is reproduced in the side bar. 5. Twitter All communication with Twitter was done via the Twitter4J library. Twitter4J is a Java...

  17. National Program for Inspection of Non-Federal Dams. Nichols Pond Dam (VT 00184), Richelieu River Basin, Woodbury, Vermont. Phase I Inspection Report.


    on pages B-12 through B-14. A letter report by ’fr. Barranco describes some of the history on page B-15. 3. Plans and sketches prepared by DuBois...Peter Barranco , Jr., P.E., Dam Safety Engineer I Subject: Nichols Pond Dam - Woodbury (252-1) The writer inspected subject dam, obtained dimensions and

  18. 5. decennial inspection of Tignes dam. Draining of the higher french dam; 5. inspection decennale du barrage de Tignes. Vidange du plus haut barrage de France



    This document deals with the 5. decennial inspection of the Tignes dam. The Tignes dam has been drained to allow EDF and the public authorities to verify the dam wall, of 180 m high, in order to validate the next decade. The four steps of the drainage are described as the maintenance policy of such building. (A.L.B.)

  19. Simulation of the thermal behaviour of a concrete dam using in situ measurements : case of Daniel-Johnson dam

    Thibeault, N. [Tecsult Inc., Montreal, PQ (Canada); Lariviere, R. [Hydro-Quebec, Montreal, PQ (Canada)


    The Daniel-Johnson Dam is the largest multiple-arch dam in the world. It was completed in 1969 at a height of 214 metres. The dam has faced many challenges related to severe thermal conditions, presence of plunging cracks in many arches and opening at the rock-concrete interface. Major concerns lie with the shear resistance in the plane of the plunging cracks. It has been determined that the main cause of arch degradation is related to the thermal behaviour of the dam. A thermal shelter was therefore constructed in the lower part of the arches. This protection has proved to be very effective. A decision was later taken to grout the plunging cracks of some arches. This involved the verification of the structural stability of the arch base. To accomplish this, the shear safety factor during the proposed injection had to be validated. This paper discussed the complex challenge of simulating the thermal behaviour of a concrete dam. It presented an alternative to the conventional methods to implement a thermal profile in a finite element model. Synthetic curves of the thermal profile were used for different thicknesses and boundary conditions. The curves were then interpolated for intermediate thicknesses. A numerical model developed for this project has been verified according to the recommendations of Bulletin 94 of ICOLD (Computer Software for Dams). The loads to consider within the framework study of the Daniel-Johnson Dam gravity; thermal gradient in summer and winter; thermal protection; hydrostatic pressure; uplift pressure in cracks; hydrostatic pressure at upstream on the grout curtain; rock-concrete contact opening; and grout pressures. The proposed method has proven to be simple, efficient and easily implemented to rapidly determine the thermal behaviour of the structures. It is also particularly well suited for multiple-arch dams. The thermal structure analysis was used to determine deformation which was compared with measurements of the pendulums. 8 refs

  20. Combating Poverty by Irrigation from Large Dams in Arid Countries: A Case Study of Minab Dam, Iran



    Full Text Available A set of indicators for sustainable development were identified to be employed in developing countries. The selected indicators provided a good understanding of social and engineering outputs of a water resources project. Results of the study revealed that there are significant positive impacts of dam construction but they were not same as the targeted objectives envisaged in the feasibility report of the project. It means that after construction of the dam and irrigation system, development didn?t match with the targeted goals of the project. This study argues the world-wide controversy against construction of dam in arid zone which is ill-founded and based on a few short term, mitigable negative impacts, ignoring many positive long term inputs alleviating chronic poverty in arid regions. The study meticulously looks into the pre dam bio-physical and socio-economic conditions in one of the arid region of Iran under the area commanded by Minab dam. This dam was constructed in Hormozgan province of Iran in 1983 and its irrigation system was completed in 1986 which was followed by progressive expansion of irrigated agriculture which almost doubled in year 2006. Literacy rate has increased from 41% (pre-project to 74% in 2006. Similarly, significant improvements were observed in health care, sanitation, education, and other disciplines.

  1. Case Study of the Chaq-Chaq Dam Failure: Parameter Estimation and Evaluation of Dam Breach Prediction Models

    Dr. KawaZedanAbdulrahman


    Full Text Available On 4th of February, 2006 at about 10:00 pm.Chaq-Chaq dam failed due to overtopping. The fall of 131.2 mm of rain over a 24-hour period was recorded at Sulaimani metrological gage station, which is located about 7.5Kmsouth-east of the dam. As a result, the reservoir level rose, the dam has been overtopped and finally breached near the spillway at the right abutment. Fortunately no human lives loss nor important structure destruction were reporteddue to the dam failure. The aim of this paper is to estimate the flood hydrograph passing through Chaq-Chaq dam breach using measured breach geometry as input to unsteady option of HEC RAS 4.1.0 and calibrating the breach formation time to obtain the measured maximum water surface at Chaq-Chaq Bridge (1.36 km downstream of dam axis. In addition the recent breach prediction models were evaluated to check their accuracy in predicting the breach geometry, breach formation time and peak breach discharge.

  2. Geophysical evaluation of the Success Dam foundation, Porterville, California

    Hunter, L.E.; Powers, M.H.; Haines, S.; Asch, T.; Burton, B.L.; Serafini, D.C.


    Success Dam is a zonedearth fill embankment located near Porterville, CA. Studies of Success Dam by the recent Dam Safety Assurance Program (DSAP) have demonstrated the potential for seismic instability and large deformation of the dam due to relatively low levels of earthquake shaking. The U.S. Army Corps of Engineers conducted several phases of investigations to determine the properties of the dam and its underlying foundation. Detailed engineering studies have been applied using a large number of analytical techniques to estimate the response of the dam and foundation system when subjected to earthquake loading. Although a large amount of data have been acquired, most are 'point' data from borings and results have to be extrapolated between the borings. Geophysical techniques were applied to image the subsurface to provide a better understanding of the spatial distribution of key units that potentially impact the stability. Geophysical investigations employing seismic refraction tomography, direct current (DC) resistivity, audio magnetotellurics (AMT) and self-potential (SP) were conducted across the location of the foundation of a new dam proposed to replace the existing one. Depth to bedrock and the occurrence of beds potentially susceptible to liquefaction were the focus of the investigations. Seismic refraction tomography offers a deep investigation of the foundation region and looks at compressional and shear properties of the material. Whereas resistivity surveys determines conductivity relationships in the shallow subsurface and can produce a relatively high-resolution image of geological units with different electrical properties. AMT was applied because it has the potential to look considerably deeper than the other methods, is useful for confirming depth to bedrock, and can be useful in identifying deep seated faults. SP is a passive electrical method that measures the electrical streaming potential in the subsurface that responds to the movement of

  3. Temporary Restoration of Bull Trout Passage at Albeni Falls Dam

    Paluch, Mark; Scholz, Allan; McLellan, Holly [Eastern Washington University Department of Biology; Olson, Jason [Kalispel Tribe of Indians Natural Resources Department


    This study was designed to monitor movements of bull trout that were provided passage above Albeni Falls Dam, Pend Oreille River. Electrofishing and angling were used to collect bull trout below the dam. Tissue samples were collected from each bull trout and sent to the U. S. Fish and Wildlife Service Abernathy Fish Technology Center Conservation Genetics Lab, Washington. The DNA extracted from tissue samples were compared to a catalog of bull trout population DNA from the Priest River drainage, Lake Pend Oreille tributaries, and the Clark Fork drainage to determine the most probable tributary of origin. A combined acoustic radio or radio tag was implanted in each fish prior to being transported and released above the dam. Bull trout relocated above the dam were able to volitionally migrate into their natal tributary, drop back downstream, or migrate upstream to the next dam. A combination of stationary radio receiving stations and tracking via aircraft, boat, and vehicle were used to monitor the movement of tagged fish to determine if the spawning tributary it selected matched the tributary assigned from the genetic analysis. Seven bull trout were captured during electrofishing surveys in 2008. Of these seven, four were tagged and relocated above the dam. Two were tagged and left below the dam as part of a study monitoring movements below the dam. One was immature and too small at the time of capture to implant a tracking tag. All four fish released above the dam passed by stationary receivers stations leading into Lake Pend Oreille and no fish dropped back below the dam. One of the radio tags was recovered in the tributary corresponding with the results of the genetic test. Another fish was located in the vicinity of its assigned tributary, which was impassable due to low water discharge at its mouth. Two fish have not been located since entering the lake. Of these fish, one was immature and not expected to enter its natal tributary in the fall of 2008. The other



    1-D and 2-D mathematical models for dam break flow were established and verified with the measured data in laboratory. The 1-D and 2-D models were then coupled, and used to simulate the dam break flow from the reservoir tail to the dam site, the propagation of dam break waves in the downstream channel, and the submergence of dam break flow in the downstream town with the hydrodynamics method. As a numerical example, the presented model was employed to simulate dam break flow of a hydropower station under construction. In simulation, different dam-break durations, upstream flows and water levels in front of dam were considered, and these influencing factors of dam break flow were analyzed, which could be referenced in planning and designing hydropower stations.

  5. Minnesota County Boundaries - lines

    Minnesota Department of Natural Resources — Minnesota county boundaries derived from a combination of 1:24,000 scale PLS lines, 1:100,000 scale TIGER, 1:100,000 scale DLG, and 1:24,000 scale hydrography lines....

  6. Counties Without a Physician.

    Getz, Virginia


    Uses a budgeting technique to determine if free-market incentives or forces would provide an economic base sufficient to support medical professionals who might practice in the approximately 140 U.S. counties that lack a physician (located mainly in a narrow band from west Texas north through South Dakota). (AH)

  7. Assessing the contribution of legacy sediment and mill dam storage to sediment budgets in the Piedmont of Maryland

    Donovan, M.; Miller, A. J.; Baker, M. E.; Gellis, A.


    Storage and remobilization of legacy sediment and its net contribution to overall watershed sediment budgets has been an active topic of research in fluvial geomorphology for at least a century. The influence of historic mill dams on storage of legacy sediment and on floodplain morphology in the Piedmont province of the mid-Atlantic region has become a prominent focus of discussion in recent years. The goals of this project are to quantify rates of remobilization of legacy sediment by bank erosion as a contribution to watershed sediment yield in the Piedmont of Baltimore County, Maryland, and to compare contributions from mill-dam deposits with contributions from floodplain sediments not directly attributable to mill dams. The watershed sample will be used to project net remobilization rates for the entire drainage network in select watersheds, and to estimate the component attributable to legacy sediments upstream of mill dams. These results will be compared with regional sediment yields documented in the literature. Through comparison of a 1-m resolution LiDAR DEM from 2005 and 1:2400 scale topographic maps from 1959-1961, we quantify nearly 50 years of channel change along 27 valley reaches from 18 watersheds with drainage areas between 1.8 and 162.9 km2. Sites chosen represent a stratified sample of stream orders and drainage areas including sites in broad alluvial valleys and upstream headwater tributaries at the limit of where floodplains are observed. Particle size and bulk density for floodplain and channel-bar sediments were determined from 182 samples cores, and were classified as Legacy material, Pre-European Settlement, or Channel material. Density and particle size were combined with the volume of gross and net erosion for each valley reach in order to calculate the net mass of sediment remobilized per year for each site. Preliminary results indicate average lateral migration rates of 0.06 - 0.29 m/year, with net erosion ranging between 24 and 171 Mg

  8. Microtremor response of the Cheongcheon dam in Korea

    Kim, Ki Young; Park, Young-Gyu


    Microtremors were analysed using the reference-dependent horizontal spectral (H/H) method and the horizontal-to-vertical spectral ratio (H/V) method to estimate site effects of the Cheongcheon earthen dam in Korea. Seismic vibrations were recorded on the dam's crest, at the toe of the dam, and in a downstream borehole using three-component accelerometers. The H/H peaks for crest versus toe-of-dam accelerations occurred at 3.1, 6.7 and 13.1 Hz with ratios of 6.9, 11.4 and 8.9, respectively. The H/V peaks for the crest of the dam occurred at 3.0, 7.0 and 13.4 Hz with ratios of 6.7, 7.8 and 5.6, respectively. The peak near 3 Hz may correspond to depth to bedrock, whereas the other peaks at higher frequencies may reflect the geometrical effect of the dam or overtone responses to the thickness of dam fill overlying the clay core. For the toe data, from the H/V spectral ratio method, the basement boundary appeared as double peaks near 8 and 10 Hz with corresponding amplification factors of 5.2 and 6.2. These may indicate a gradual change in velocity across the basement boundary at ~10 m depth. The third resonance, which occurred at 15 Hz, may correlate with the refraction boundary at 5-6 m depth in the overburden layer. Both the frequencies and magnitudes of resonance derived from the H/H and H/V methods are reasonably well matched to the theoretical response curves computed by the reflection and transmission matrix and the two-dimensional finite difference methods.

  9. The behaviour of a large dam at severe frost

    M. C. SPADEA


    Full Text Available Synthesizing the problem, the action of the thrusts in the
    behaviour of t h e dam of Pieve di Cadore, makes itself conspicuous expecially
    during three periods of the year:
    1. - About the end of June, the air temperature, 011 t h e average, overcomes
    the water one in the watershed upstream the dam: the bending of
    t h e dam upstream increases from the bottom to the top.
    2. - About the end of October, the thermal conditions change; the
    mean air temperature grows lower than the mean water temperature; the
    dam begins her bending dowstream.
    3. - When the air temperature is distinctly below 0 °C, the action of
    t h e t h r u s t s grows more complexe; t h e rocky waterlogged system downstream
    of t h e dam, while cooling, swells and pushes t h e bottom of t h e dam upstream;
    at t h e higher quote, on the contrary, the t h r u s t downstream continues.
    When the strenght limit of the medium is surpassed, arises a contrast
    between the rocky system and the concrete structure: this contrast can origin
    a t e very small fractures, revealed from seismic station installed into the
    central ashlar (XIV a t 660 metres height of t h e dam, under t h e form of microshocks
    which energy is of about 10I0-10U erg.

  10. Dam foundation excavation techniques in China:A review

    Yuzhu Zhang; Wenbo Lu; Ming Chen; Peng Yan; Yingguo Hu


    A protective layer (PL) is commonly reserved above foundation surface to protect the underlying rock mass during dam foundation excavation. In China, the PL of dam foundation is conventionally subdivided into two or three thin layers and excavated with the shallow-hole blasting method, even by pneumatic pick method in case of soft rock mass. The aforementioned layered excavation of the PL delays the con-struction of the whole project. After nearly 30-year practices, several safe and efficient methods for the PL excavation of dam foundation are gradually developed. They include shallow-hole bench blasting with cushion material (SBC) at the bottom of the hole, and horizontal smooth blasting (HSB). The PL is even can-celled on the condition that horizontal pre-split technique is employed during dam foundation excavation. This paper introduces the aforementioned two PL excavation methods (shallow-hole blasting and bench blasting) and horizontal pre-split technique of dam foundation without protective layer (HPP). The basic principles of blasting method, blasting geometry, charge structure, drill-and-blast parameters of typical projects are examined. Meanwhile, the merits and limitations of each method are compared. Engineering practices in China show that HSB is basically the optimal method for dam foundation PL excavation in terms of foundation damage control and rapid construction. Some new problems for dam foundation PL excavation arising, such as strong unloading and relaxation phenomenon that encountered in the gorge region of southwest China, are needed to be addressed; and the corresponding countermeasures are discussed as well.

  11. Dams. Bulletin of the technical service of electric power and big dams; Barrages. Bulletin du service technique de l`energie electrique et des grands barrages

    Davard, J.


    The Dams bulletin reports on technical news concerning big French dams in operation. This issue comprises 5 papers. Two of them are examples of granting problems which led to the dismantling of the dams of Kernansquillec (Cotes d`Armor, France) and Maisons-Rouges (Indre-et-Loire, France) for economical and environmental reasons. The 3 other papers concern the life of French dams (technical control reports of the French dams in operation), the activities of the control service (annual inspections, preparation of draining operations, renewing of granting), and some general information (organisation of competent authorities, colloquium reports, hydro-power production during the first quarter of 1997). (J.S.)

  12. Flood of February 1980 along the Agua Fria River, Maricopa County, Arizona

    Thomsen, B.W.


    The flood of February 20, 1980, along the Agua Fria River below Waddell Dam, Maricopa County, Ariz., was caused by heavy rains during February 13-20. The runoff filled Lake Pleasant and resulted in the largest release--66,600 cubic feet per second--from the reservoir since it was built in 1927; the maximum inflow to the reservoir was about 73,300 cubic feet per second. The area inundated by the releases includes about 28 miles along the channel from the mouth of the Agua Fria River to the Beardsley Canal flume crossing 5 miles downstream from Waddell Dam. The flood of 1980 into Lake Pleasant has a recurrence interval of about 47 years, whereas the flood of record (1919) has a recurrence interval of about 100 years. (USGS)

  13. Large Dam Effects on Flow Regime and Hydraulic Parameters of river (Case study: Karkheh River, Downstream of Reservoir Dam

    Farhang Azarang


    Full Text Available Introduction: The critical role of the rivers in supplying water for various needs of life has led to engineering identification of the hydraulic regime and flow condition of the rivers. Hydraulic structures such dams have inevitable effects on their downstream that should be well investigated. The reservoir dams are the most important hydraulic structures which are the cause of great changes in river flow conditions. Materials and Methods: In this research, an accurate assessment was performed to study the flow regime of Karkheh river at downstream of Karkheh Reservoir Dam as the largest dam in Middle East. Karkheh River is the third waterful river of Iran after Karun and Dez and the third longest river after the Karun and Sefidrud. The Karkheh Dam is a large reservoir dam built in Iran on the Karkheh River in 2000. The Karkheh Reservoir Dam is on the Karkheh River in the Northwestern Khouzestan Province, the closest city being Andimeshk to the east. The part of Karkheh River, which was studied in this research is located at downstream of Karkheh Reservoir Dam. This interval is approximately 94 km, which is located between PayePol and Abdolkhan hydrometric stations. In this research, 138 cross sections were used along Karkheh River. Distance of cross sections from each other was 680m in average. The efficient model of HEC-RAS has been utilized to simulate the Karkheh flow conditions before and after the reservoir dam construction using of hydrometric stations data included annually and monthly mean discharges, instantaneous maximum discharges, water surface profiles and etc. Three defined discharges had been chosen to simulate the Karkheh River flow; maximum defined discharge, mean defined discharge and minimum defined discharge. For each of these discharges values, HEC-RAS model was implemented as a steady flow of the Karkheh River at river reach of study. Water surface profiles of flow, hydraulic parameters and other results of flow regime in

  14. Putting Roman Dams in Context: a Virtual Approach

    Decker, M. J.; Du Vernay, J. P.; Mcleod, J. B.


    Water resources and management have become a critical global issue. During the half-millennium of its existence, the Roman Empire developed numerous strategies to cope with water management, from large-scale urban aqueduct systems, to industrial-scale water mills designed to cope with feeding growing city populations. Roman engineers encountered, adopted, and adapted indigenous hydraulic systems, and left lasting imprints on the landscape of the Mediterranean and temperate Western Europe by employing a range of water technologies. A recent academic study has enabled the identification of remains of and references to seventy-two dams from the Roman era, constructed in Spain between the 1st and 4th century AD. Such unique heritage, without comparisons in the Mediterranean makes Spain an emblematic case study for the analysis of Roman hydraulic engineering and water management policies. Fifty dams have been located and detailed. The twenty-two outstanding, although identified on the ground, have not been able to be acceptably characterized, due in some cases to their being ruins in a highly degraded state, others due to their being masked by repairs and reconstructions subsequent to the Roman era. A good example of such neglected dams is the buttress dam of Consuegra , in Toledo province (Castilla-La Mancha). Dating to the 3rd - 4th century AD, the Dam of Consuegra, on the basin of the Guadiana, with its over 600 metres length and 4,80 metres height, is a remarkable case of Roman engineering mastery. It had a retaining wall upstream, numerous buttresses and perhaps an embankment downstream, of which no remains are left. The application of 3D digital imaging technique to create a high quality virtual model of such monuments has proved to be successful especially for the study of the technological aspects related its construction. The case study of the Roman dam of Muel (Zaragoza) has shown, in fact, as best practices in digital archaeology can provide an original and

  15. Experiences from the small historical dams failures during heavy floods

    Vaníček, I.; Vaníček, M.; Jirásko, D.; Pecival, T.


    Roughly between 400 and 600 years ago many small earth dams were constructed mainly in the south part of the Czech Republic. They were used for fish production and flood protection. To our days roughly one third survived, which means about 25 000 of them. During catastrophic floods in 2002 many of them had some problems but less than 0.3% failed. Experiences gained from the failure evaluation are presented. Firstly from the view of limit states of failures, when limit states of internal erosion and surface erosion played most important role and were the main reason of failures. Secondly, from the view of so called domino effect of failure, when the most important dam on the catchment basin failed and after that the other ones, situated below, had limited chance to survive. The failures are described for catchment basin of the small river Lomnice in south part of the Czech Republic close to the town Blatna. The experiences obtained there led to the evaluation of other catchment basins where domino effect of failure can play also very important role. For the evaluation of potential risk, the numerical modelling was used to study the flood wave propagation below the critical dam, especially at the moment when this wave is reaching the dam situated below the critical one. Finally, the recommendations are specified, not only for individual dams but also for catchment basin, where the risk of domino effect failure is very high.

  16. Geophysical investigation of seepage beneath an earthen dam.

    Ikard, S J; Rittgers, J; Revil, A; Mooney, M A


    A hydrogeophysical survey is performed at small earthen dam that overlies a confined aquifer. The structure of the dam has not shown evidence of anomalous seepage internally or through the foundation prior to the survey. However, the surface topography is mounded in a localized zone 150 m downstream, and groundwater discharges from this zone periodically when the reservoir storage is maximum. We use self-potential and electrical resistivity tomography surveys with seismic refraction tomography to (1) determine what underlying hydrogeologic factors, if any, have contributed to the successful long-term operation of the dam without apparent indicators of anomalous seepage through its core and foundation; and (2) investigate the hydraulic connection between the reservoir and the seepage zone to determine whether there exists a potential for this success to be undermined. Geophysical data are informed by hydraulic and geotechnical borehole data. Seismic refraction tomography is performed to determine the geometry of the phreatic surface. The hydro-stratigraphy is mapped with the resistivity data and groundwater flow patterns are determined with self-potential data. A self-potential model is constructed to represent a perpendicular profile extending out from the maximum cross-section of the dam, and self-potential data are inverted to recover the groundwater velocity field. The groundwater flow pattern through the aquifer is controlled by the bedrock topography and a preferential flow pathway exists beneath the dam. It corresponds to a sandy-gravel layer connecting the reservoir to the downstream seepage zone.

  17. Applying Mechanistic Dam Breach Models to Historic Levee Breaches

    Risher Paul


    Full Text Available Hurricane Katrina elevated levee risk in the US national consciousness, motivating agencies to assess and improve their levee risk assessment methodology. Accurate computation of the flood flow magnitude and timing associated with a levee breach remains one of the most difficult and uncertain components of levee risk analysis. Contemporary methods are largely empirical and approximate, introducing substantial uncertainty to the damage and life loss models. Levee breach progressions are often extrapolated to the final width and breach formation time based on limited experience with past breaches or using regression equations developed from a limited data base of dam failures. Physically based embankment erosion models could improve levee breach modeling. However, while several mechanistic embankment breach models are available, they were developed for dams. Several aspects of the levee breach problem are distinct, departing from dam breach assumptions. This study applies three embankments models developed for dam breach analysis (DL Breach, HR BREACH, and WinDAM C to historic levee breaches with observed (or inferred breach rates, assessing the limitations, and applicability of each model to the levee breach problem.

  18. A Method for Probabilistic Stability Analysis of Earth Dams

    T. R. Mafioleti


    Full Text Available This paper proposes a new probabilistic methodology for analyzing the stability of Earth Dams, based on the technique of the First Order Reliability Method for Structural Reliability. Differently from others methodologies present in literature, the proposed method interprets the involved variables as random ones. So, three results are provided here: the Structural Reliability Index, the Probability of Rupture and the most probable values of the random variables for the occurrence of a dam break. In order to illustrate it, real data from a cross section of the Left Bank Earthfill Dam of Itaipu Hydroelectric Power Plant (IHPP, located on the city of Foz do Iguaçu, Paraná, Brazil were used. The numerical results achieved by the proposed methodology evidence that IHPP dam has currently good structural conditions, confirming that the safety procedures adopted in Itaipu Dam may be considered as appropriate. The use of the proposed method enables to complement the previously existing knowledge about the structural conditions, improving the process of risk management.

  19. Bathymetry and capacity of Blackfoot Reservoir, Caribou County, Idaho, 2011

    Wood, Molly S.; Skinner, Kenneth D.; Fosness, Ryan L.


    The U.S. Geological Survey (USGS), in cooperation with the Shoshone-Bannock Tribes, surveyed the bathymetry and selected above-water sections of Blackfoot Reservoir, Caribou County, Idaho, in 2011. Reservoir operators manage releases from Government Dam on Blackfoot Reservoir based on a stage-capacity relation developed about the time of dam construction in the early 1900s. Reservoir operation directly affects the amount of water that is available for irrigation of agricultural land on the Fort Hall Indian Reservation and surrounding areas. The USGS surveyed the below-water sections of the reservoir using a multibeam echosounder and real-time kinematic global positioning system (RTK-GPS) equipment at full reservoir pool in June 2011, covering elevations from 6,090 to 6,119 feet (ft) above the North American Vertical Datum of 1988 (NAVD 88). The USGS used data from a light detection and ranging (LiDAR) survey performed in 2000 to map reservoir bathymetry from 6,116 to 6,124 ft NAVD 88, which were mostly in depths too shallow to measure with the multibeam echosounder, and most of the above-water section of the reservoir (above 6,124 ft NAVD 88). Selected points and bank erosional features were surveyed by the USGS using RTK-GPS and a total station at low reservoir pool in September 2011 to supplement and verify the LiDAR data. The stage-capacity relation was revised and presented in a tabular format. The datasets show a 2.0-percent decrease in capacity from the original survey, due to sedimentation or differences in accuracy between surveys. A 1.3-percent error also was detected in the previously used capacity table and measured water-level elevation because of questionable reference elevation at monitoring stations near Government Dam. Reservoir capacity in 2011 at design maximum pool of 6,124 ft above NAVD 88 was 333,500 acre-ft.

  20. Dynamic probability evaluation of safety levels of earth-rockfill dams using Bayesian approach

    Zi-wu FAN; Shu-hai JIANG; Ming ZHANG


    In order to accurately predict and control the aging process of dams, new information should be collected continuously to renew the quantitative evaluation of dam safety levels. Owing to the complex structural characteristics of dams, it is quite difficult to predict the time-varying factors affecting their safety levels. It is not feasible to employ dynamic reliability indices to evaluate the actual safety levels of dams. Based on the relevant regulations for dam safety classification in China, a dynamic probability description of dam safety levels was developed. Using the Bayesian approach and effective information mining, as well as real-time information, this study achieved more rational evaluation and prediction of dam safety levels. With the Bayesian expression of discrete stochastic variables, the a priori probabilities of the dam safety levels determined by experts were combined with the likelihood probability of the real-time check information, and the probability information for the evaluation of dam safety levels was renewed. The probability index was then applied to dam rehabilitation decision-making. This method helps reduce the difficulty and uncertainty of the evaluation of dam safety levels and complies with the current safe decision-making regulations for dams in China. It also enhances the application of current risk analysis methods for dam safety levels.

  1. Flood hydrology and dam-breach hydraulic analyses of five reservoirs in Colorado

    Stevens, Michael R.; Hoogestraat, Galen K.


    The U.S. Department of Agriculture Forest Service has identified hazard concerns for areas downstream from five Colorado dams on Forest Service land. In 2009, the U.S. Geological Survey, in cooperation with the Forest Service, initiated a flood hydrology analysis to estimate the areal extent of potential downstream flood inundation and hazard to downstream life, property, and infrastructure if dam breach occurs. Readily available information was used for dam-breach assessments of five small Colorado reservoirs (Balman Reservoir, Crystal Lake, Manitou Park Lake, McGinnis Lake, and Million Reservoir) that are impounded by an earthen dam, and no new data were collected for hydraulic modeling. For each reservoir, two dam-breach scenarios were modeled: (1) the dam is overtopped but does not fail (break), and (2) the dam is overtopped and dam-break occurs. The dam-breach scenarios were modeled in response to the 100-year recurrence, 500-year recurrence, and the probable maximum precipitation, 24-hour duration rainstorms to predict downstream flooding. For each dam-breach and storm scenario, a flood inundation map was constructed to estimate the extent of flooding in areas of concern downstream from each dam. Simulation results of the dam-break scenarios were used to determine the hazard classification of the dam structure (high, significant, or low), which is primarily based on the potential for loss of life and property damage resulting from the predicted downstream flooding.

  2. The effects of turbine passage on C-start behavior of salmon at the Wanapum Dam, Washington

    Cada, Glenn F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ryon, Michael G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Smith, John G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Luckett, Cloe A. [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States)


    In 2005, Grant County Public Utility District No. 2 (GCPUD) replaced one of the 10 Kaplan turbines at Wanapum Dam with an advanced turbine that was developed with support from the U.S. Department of Energy’s Advanced Hydropower Turbine System Program. Compared to a conventional Kaplan turbine, the advanced minimum gap runner (MGR) turbine is predicted to have lower values for several potential fish injury mechanisms, and therefore was expected to improve turbine-passage fish survival. Fish survival tests of the new turbine were carried out by GCPUD between February and April 2005. A total of 8,960 tagged juvenile summer Chinook salmon were used to quantify the differences in direct mortality associated with turbine passage for the new and old turbines. There were few test conditions in which the study was noted a distinct difference between the old Kaplan turbine and the new MGR turbine on the basis of changes in the escape behavior of uninjured fish.

  3. Castleward, County Down

    Fisher, Jonathan


    Fisher was a painter and engraver in Ireland, working after the Dutch and Italian landscape painting tradition. He is best known by engravings after his designs, of which a large number were produced during his career.[notes from Irish Paintings in the `National Gallery of Ireland?, 2001]The house depicted in the present painting is Castle Ward, located in County Down, Northern Ireland. The 18th century house is famed for its mixture of Classical and Gothic styles.

  4. Vortices in dam reservoir: A case study of Karun III dam

    Maryam Azarpira; Hamed Sarkardeh; Sasan Tavakkol; Reza Roshan; Hossein Bakhshi


    The present study focuses on the effect of vortex formation on plane velocities in a reservoir. Velocity measurements are performed in the hydraulic model of Karun III dam and hydropower plant. Different vortices were produced at the horizontal intake by changing the submerged depth. Tangential velocities were measured on a rectangular mesh in the reservoir. The results were then processed to plot the contour lines of the plane velocities and study the effect of vortex formation on the flow condition in the reservoir. Contour lines in different submerged depths show that circulation zones are formed in different potential locations over the intakes causing vortex formation. These results were correlated with the location of the appearing vortices observed in the experiments. Experimental data of this study could be useful for numerical modelling of vortex in the reservoirs.

  5. Sediment trapping by dams creates methane emission hot spots

    Maeck, A.; Delsontro, T.; McGinnis, Daniel F.


    Inland waters transport and transform substantial amounts of carbon and account for similar to 18% of global methane emissions. Large reservoirs with higher areal methane release rates than natural waters contribute significantly to freshwater emissions. However, there are millions of small dams...... worldwide that receive and trap high loads of organic carbon and can therefore potentially emit significant amounts of methane to the atmosphere. We evaluated the effect of damming on methane emissions in a central European impounded river. Direct comparison of riverine and reservoir reaches, where...... sedimentation in the latter is increased due to trapping by dams, revealed that the reservoir reaches are the major source of methane emissions (similar to 0.23 mmol CH4 m(-2) d(-1) vs similar to 19.7 mmol CH4 m(-2) d(-1), respectively) and that areal emission rates far exceed previous estimates for temperate...

  6. Social Discounting of Large Dams with Climate Change Uncertainty

    Marc Jeuland


    This paper reviews the recent discounting controversy and examines its implications for the appraisal of an illustrative hydropower project in Ethiopia. The analysis uses an integrated hydro-economic model that accounts for how the dam’s transboundary impacts vary with climate change. The real value of the dam is found to be highly sensitive to assumptions about future economic growth. The argument for investment is weakest under conditions of robust global economic growth, particularly if these coincide with unfavourable hydrological or development factors related to the project. If however long-term growth is reduced, the value of the dam tends to increase. There may also be distributional or local arguments favouring investment, if growth in the investment region lags behind that of the rest of the globe. In such circumstances, a large dam can be seen as a form of insurance that protects future vulnerable generations against the possibility of macroeconomic instability or climate shocks.

  7. Roles for Dam methylation in bacterial chromosome replication

    Charbon, Godefroid; Koch, Birgit; Skovgaard, Ole;

    GATC sequences in the DNA of Escherichia coli and related species are methylated at the adenine residue by DNA adenine methyltransferase (DamMT). These methylated residues and/or the level of DamMT influence initiation of chromosome replication from the replication origin, oriC, which contain...... an over-representation of GATC sites, in at least two ways. First, full methylation of oriC promotes duplex opening and hence certain oriC mutants are dependent on Dam methylation for initiation. Second, newly replicated and hemimethylated origins, are bound by SeqA (‘sequestered’) and remain inactive...... for initiation is not affected by additional SeqA whereas DnaA binding to sites outside the origin is inhibited by increased sequestration and/or hemimethylation....


    Kholopov Igor' Serafimovich


    Full Text Available The following conclusions were made upon completion of the testing of crane beams: The lowest rigidity is demonstrated by welded beams exposed to temporary mobile loads; the maximal buckling caused by temporary mobile loads is equal to 12 mm, or 1/1,1790 of the span; the rigidity of crane beams of an overflow dam meets the requirements set by Section E2.1 of Construction Rules 20.13330.2011 "Loads and Actions". In general, the authors state that the crane beams of the span structure of the overflow dam are in a serviceable operating condition, according to their opinion issued upon completion of examination and testing procedures. The recommendation is to regularly tighten screw nuts and to install high-strength bolts in the points of missing rivets. The authors also recommend applying a rust-proofing coating to all metal structures of the dam spans.

  9. A Hidden-Removal Model of Dam Perspective Drawing

    WANG Zi-ru; ZHOU Hui-cheng; LI Ming-qiu


    Aming at water conservancy project visualization, a hidden-removal method of dam perspective drawings is realized by building a hidden-removal mathematical model for overlapping points location to set up the hidden relationship among point and plane, plane and plane in space. On this basis, as an example of panel rockfill dam, a dam hidden-removal perspective drawing is generated in different directions and different visual angles through adapting VC++ and OpenGL visualizing technology. The results show that the data construction of the model is simple which can overcome the disadvantages of considerable and complicated calculation. This method also provides the new means to draw hidden-removal perspective drawings for those landforms and ground objects.

  10. Environmental Risk Assessment System for Phosphogypsum Tailing Dams

    Xin Sun


    Full Text Available This paper may be of particular interest to the readers as it provides a new environmental risk assessment system for phosphogypsum tailing dams. In this paper, we studied the phosphogypsum tailing dams which include characteristics of the pollution source, environmental risk characteristics and evaluation requirements to identify the applicable environmental risk assessment methods. Two analytical methods, that is, the analytic hierarchy process (AHP and fuzzy logic, were used to handle the complexity of the environmental and nonquantitative data. Using our assessment method, different risk factors can be ranked according to their contributions to the environmental risk, thereby allowing the calculation of their relative priorities during decision making. Thus, environmental decision-makers can use this approach to develop alternative management strategies for proposed, ongoing, and completed PG tailing dams.

  11. Environmental risk assessment system for phosphogypsum tailing dams.

    Sun, Xin; Ning, Ping; Tang, Xiaolong; Yi, Honghong; Li, Kai; Zhou, Lianbi; Xu, Xianmang


    This paper may be of particular interest to the readers as it provides a new environmental risk assessment system for phosphogypsum tailing dams. In this paper, we studied the phosphogypsum tailing dams which include characteristics of the pollution source, environmental risk characteristics and evaluation requirements to identify the applicable environmental risk assessment methods. Two analytical methods, that is, the analytic hierarchy process (AHP) and fuzzy logic, were used to handle the complexity of the environmental and nonquantitative data. Using our assessment method, different risk factors can be ranked according to their contributions to the environmental risk, thereby allowing the calculation of their relative priorities during decision making. Thus, environmental decision-makers can use this approach to develop alternative management strategies for proposed, ongoing, and completed PG tailing dams.

  12. Detection of subcritical crack propagation for concrete dams

    BAO TengFei; YU Hong


    Subcritical propagation of cracks is a warning sign of fracture.If such propagation is detected at an early stage,timely maintenance measures can be taken to prevent the failure of structures.To detect the subcritical propagation of a crack,the crack needs to be monitored continuously in a long term,which is not realistic under certain conditions.However,cracks in concrete dams can be monitored continuously by dam monitoring to offer possible detection for subcritical propagation.In this paper,with measured crack openings from dam monitoring,a state equation for characterizing crack development is established based on the grey system theory.The relation between the stability of the equation and the subcritical crack propagation is investigated,then a criterion is proposed for detecting subcritical propagation.An example demonstrates the validity of the criterion and its potential for practical application.

  13. Analysis of the behaviour of the Toulnoustouc CFRD Dam

    Bouzaiene, H.; Chartrand, C. [RSW Inc., Montreal, PQ (Canada); Hammamji, Y. [Hydro-Quebec, Montreal, PQ (Canada)


    Concrete-face rockfill dams (CFRD) are typically designed using empirical methods which occasionally lead to leakage problems and the need for remedial measures. This paper argued that the application of numerical simulations in dam design may provide a greater understanding of CFRD dam behaviour. A 3D finite element method was used for the basic design of the Toulnustouc dam in Quebec. The interaction between the face concrete slabs, rockfill, and the rigid foundation was modelled with a specific emphasis on discontinuities of the concrete slabs. Data from a topographical survey was used to consider the rock excavation, dental concrete and the plinth alignment discontinuities. The rockfill modulus was calibrated using a 2D non-linear elastic model with plane deformation. Results of the modelling study were used to confirm the location of compression and tension joints for water stops design. The study showed that most of the joint sealing defects of CFRD dams were located at joints between slabs and at the plinth perimeter joint. Various analyses were then conducted to evaluate stress concentration in the reinforced concrete slabs and the variation of stresses with the rockfill deformation modulus as well as the contact points between the slab and the fill. It was observed that changes in plinth alignment introduced important tension stresses in the upstream face of the slabs within a band of 12 meters along the perimeter joint. Stresses were governed by the difference of rigidity of the fill and the developed friction forces between the fill and the slabs. It was concluded that the finite element model was useful in determining the behaviour of the CFRD dam. 3 refs., 15 figs.

  14. Environmental risk assessment of a dam during construction phase

    S. Rezaian


    Full Text Available The present study was conducted to assess the possible risks induced by construction of Gavi Dam in Ilam Province; western part of Iran, using MIKE-11 model and technique for order of preference by similarity to ideal solution. For this purpose, vulnerable zone of the dam site against the flooding risk of Gavi River was calculated for different return periods. The flooding zones were stimulated by MIKE-11 model. In order to check whether or not the dam construction could affect the quality of the Gavi River, the physicochemical quality of the river water was also tested. Afterwards, a questionnaire was prepared containing an inventory of possible risks supposed to be induced by construction of Gavi Dam. The questionnaires were placed at disposal of experts to score the items based on their importance. The questionnaires were then analyzed using SPSS Software, version 16. According to which, a total number of 12 risk factors were identified. The dam construction risks were qualitatively assessed by preliminary hazard analysis. Based on the results, 3 of 12 identified risks were recognized unacceptable. The shortlisted risks were prioritized at final step using technique for order of preference by similarity to ideal solution. "Habitat fragmentation" with a weight of 0.3002, "water pollution" with a weight of 0.295, and "impacts on aquatics" with a weight of 0.293 were identified as three top priority flooding risks. Among the most important corrective measures for mitigation of the risks at construction phase can be pointed to "restoration of the land cover", “conservation of areas surrounding the dam as a new wildlife habitat", “prevention of water contamination”, and "conservation of fish spawning sites".

  15. Introduction of an Emergency Response Plan for flood loading of Sultan Abu Bakar Dam in Malaysia

    Said, N. F. Md; Sidek, L. M.; Basri, H.; Muda, R. S.; Razad, A. Z. Abdul


    Sultan Abu Bakar Dam Emergency Response Plan (ERP) is designed to assist employees for identifying, monitoring, responding and mitigation dam safety emergencies. This paper is outlined to identification of an organization chart, responsibility for emergency management team and triggering level in Sultan Abu Bakar Dam ERP. ERP is a plan that guides responsibilities for proper operation of Sultan Abu Bakar Dam in respond to emergency incidents affecting the dam. Based on this study four major responsibilities are needed for Abu Bakar Dam owing to protect any probable risk for downstream which they can be Incident Commander, Deputy Incident Commander, On-Scene Commander, Civil Engineer. In conclusion, having organization charts based on ERP studies can be helpful for decreasing the probable risks in any projects such as Abu Bakar Dam and it is a way to identify and suspected and actual dam safety emergencies.

  16. Crucial technologies in High the design of Xiluodu Super Arch Dam

    Wang Renkun


    Some super high arch dams ( SHADs), like Xiluodu Arch Dam, after their heights reaching the magnitude of 300 m, confront lots of technical challenges in design and construction. Several crucial technologies of 6 SHADs will be reviewed and discussed in this and consecutive papers, including Xiluodu, Jinping I in China, Baktiary in Iran, ete. , on the topics of the research method, criterion for evaluation and engineering application of dam safety analysis and evaluation, reasonable dam base interface, dam shape optimization, comprehensive treatments of complex foundation, anti-seismic engineering, dam construction material, concrete placement and temperature control, instrumentation and monitoring of dam operation, etc. This paper will mainly focus on the overall safety of SHADs, reasonable dam base interface analysis and evaluation and their engineering application.

  17. Wear and Thermal Stress Analysis of Side Dam for Twin Roll Strip Casting

    LI Chao-feng; DI Hong-shuang; ZHANG Xiao-ming; WANG Guo-dong; LIU Xiang-hua


    The side dam technology for twin roll strip casting was discussed. The effect of pre-heating temperature, material and design of side dam on the process stability and surface quality of products was analyzed. The wear and erosion of side dam for different steel grades were described. Two types of side dam designs, namely integral type and combined type, were used in the experiment, and the suitable position of side dam was determined by experiment. The results show that the combined side dam is better than the integral one in process stability and long service life. The temperature fields and thermal stress fields in side dam during strip casting were analyzed using the finite element analysis software, and the causes of side dam cracking were explained.

  18. Prediction of downstream geomorphological changes after dam construction: A stream power approach

    Brandt, Anders


    physical geography, hydrology, reservoirs, sediment transport, erosion, sedimentation, fluvial geomorphology, dams, river channel geometry......physical geography, hydrology, reservoirs, sediment transport, erosion, sedimentation, fluvial geomorphology, dams, river channel geometry...

  19. EnviroAtlas - National Inventory of Dams for the Conterminous United States

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is a summary of the National Dams Inventory data from 2009 survey. The file contains counts of inventoried dams by 12-digit hydrologic...

  20. Thermal margin comparison between DAM and simple model

    Cha, Jeonghun; Yook, Daesik [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)


    The nuclear industry in Korea, has considered using a detail analysis model (DAM), which described each rod, to get more thermal margin with the design a dry storage facility for nuclear spent fuel (NSF). A DAM is proposed and a thermal analysis to determine the cladding integrity is performed using test conditions with a homogenized NSF assembly analysis model(Simple model). The result show that according to USA safety criteria, temperature of canister surface has to keep below 500 K in normal condition and 630 K in excess condition. A commercial Computational Fluid Dynamics (CFD) called ANSYS Fluent version 14.5 was used.

  1. Merowe Dam and the inundation of paleochannels of the Nile

    Sparavigna, Amelia Carolina


    The course of the Nile in northern Sudan follows a contorted path through bedrocks, creating the Great Bend. Few years ago, the satellite images showed a fertile strip of land with villages, where paleochannels of the river hosted many fields with cultivations and archaeological sites. Now, a huge part of this valley is under the waters of Merowe Dam reservoir. Comparing the images of the region before and after the dam gates were closed, we can see that the reservoir created itself through flooding the paleochannels.

  2. Rollers in low-head dams - Challenges and solutions

    Zamankhan, Piroz


    Low-head dams exist in many rivers for the purposes of diverting water for open-channel irrigation and providing power plants with cooling water. Flow over low-head dams is quite complex and dangerous rollers often develop down-stream that tend to trap and submerge floating objects. This paper presents an analysis of the problem based on physical and computational fluid dynamics (CFD) modeling and the result of this analysis in the form of design suggestions intended to diminish the hazards associated with rollers.

  3. Conception of a synthesis pozzolan from sediment dams calcined (Case: Gargar dams

    Ouhba K.


    The analysis by the diffraction of x-rays (X-ray and the differential thermal analysis (DTA show that the chemical reactions between principal minerals of the vase used and cement give the formation of new products such as the freezing of HSC and the tobermorite.

  4. Somerset County Renewable Energy Initiative

    Katula, Denise [County of Somerset, Somervile, NJ (United States)


    The County of Somerset, New Jersey, through the Somerset County Improvement Authority (SCIA), applied Federal funding through the U.S. Department of Energy to will apply project funds to buy-down the capital costs of equipment associated with the installation of solar photovoltaic (PV) systems at two sites owned by the County. This Renewable Energy Initiative allows the County to take advantage of clean renewable energy, without any adverse debt impacts, and at a price that results in operating budget savings beyond what is presently available in the marketplace. This project addressed the objectives of the Office of Energy Efficiency and Renewable Energy by making the acquisition of renewable energy more affordable for the County, thereby, encouraging other counties and local units to develop similar programs and increase the deployment of solar energy technologies. The two sites that were funded by the DOE grant are part of a much larger, ambitious, and unique renewable energy project, described in the next section.

  5. Large dams and alluvial rivers in the Anthropocene: The impacts of the Garrison and Oahe Dams on the Upper Missouri River

    Skalak, Katherine; Benthem, Adam J.; Schenk, Edward R.; Hupp, Cliff R.; Galloway, Joel M.; Nustad, Rochelle A.; Wiche, Gregg J.


    The Missouri River has had a long history of anthropogenic modification with considerable impacts on river and riparian ecology, form, and function. During the 20th century, several large dam-building efforts in the basin served the needs for irrigation, flood control, navigation, and the generation of hydroelectric power. The managed flow provided a range of uses, including recreation, fisheries, and habitat. Fifteen dams impound the main stem of the river, with hundreds more on tributaries. Though the effects of dams and reservoirs are well-documented, their impacts have been studied individually, with relatively little attention paid to their interaction along a river corridor. We examine the morphological and sedimentological changes in the Upper Missouri River between the Garrison Dam in ND (operational in 1953) and Oahe Dam in SD (operational in 1959). Through historical aerial photography, stream gage data, and cross sectional surveys, we demonstrate that the influence of the upstream dam is still a major control of river dynamics when the backwater effects of the downstream reservoir begin. In the “Anthropocene”, dams are ubiquitous on large rivers and often occur in series, similar to the Garrison Dam Segment. We propose a conceptual model of how interacting dams might affect river geomorphology, resulting in distinct and recognizable morphologic sequences that we term “Inter-Dam sequence” characteristic of major rivers in the US.

  6. Compliance Monitoring of Subyearling Chinook Salmon Smolt Survival and Passage at Bonneville Dam, Summer 2012

    Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.


    The purpose of this compliance study was to estimate dam passage survival of subyearling Chinook salmon at Bonneville Dam during summer 2012, as required by the 2008 Federal Columbia River Power System Biological Opinion. The study also estimated smolt passage survival from the forebay 2 km upstream of the dam to the tailrace 1 km below the dam, as well as forebay residence time, tailrace egress, and spill passage efficiency, as required in the 2008 Columbia Basin Fish Accords.

  7. Seismic Fortification Analysis of the Guoduo Gravity Dam in Tibet, China

    Peng Lin; Wenwei Zheng; Bo Huang; Haichao Zhang


    The primary aim of this research was to analyze the seismic performance of the Guoduo gravity dam. A nonlinear FEM method was implemented to study the deformation, stress, and overall stability of dam under both static and dynamic loading conditions, including both normal and overloading conditions. A dam seismic failure risk control method is proposed based on the cracking mechanism induced by the dynamic load to ensure dam safety and stability. Numerical simulation revealed that (1) under n...

  8. Past, Present, and Future Nutrient Quality of a Small Southeastern River: A Pre-Dam Assessment

    Stewart, Paul M.; Miller, Jonathan M


    Riverine dams alter both the physical environment and water chemistry, thus affecting species assemblages within these environments. In the United States, dam construction is on the decline and there is a growing trend for dam removal. The Choctawhatchee, Pea, and Yellow Rivers Watershed Management Authority had initiated the permitting process for placing a reservoir dam on the Little Choctawhatchee River (LCR), a tributary to the Choctawhatchee River. The purpose of the proposed reservoir w...

  9. Alba County - Rural Tourism Destination?

    Claudia Olimpia Moisa


    Full Text Available The purpose of this paper is to identify the main rural touristic resources available in Alba County and also the preferred tourist destinations, highlighting the role and the importance of the rural tourism and agro-tourism in the economy of Alba County and, not least, identifying the main direction for its development and promotion. In other words, the aim of this paper is to answer the question "Is it or not Alba County a rural tourist destination?"

  10. A continous Bayesian network for earth dams' risk assessment: methodology and quantification

    Morales-Napoles, O.; Delgado-Hernadez-D.J.; De-Leon-Escobedo, D.; Arteaga-Arcos, J.C.


    Dams’ safety is highly important for authorities around the world. The impacts of a dam failure can be enormous. Models for investigating dam safety are required for helping decision-makers to mitigate the possible adverse consequences of flooding. A model for earth dam safety must specify clearly p

  11. The Cemented Material Dam: A New, Environmentally Friendly Type of Dam

    Jinsheng Jia Michel Lino Feng Jin Cuiying Zheng


    The first author proposed the concept of the cemented material dam (CMD) in 2009. This concept was aimed at building an environmentally friendly dam in a safer and more economical way for both the dam and the area downstream...

  12. Characteristics of stress distribution in trapezoid-shaped CSG dam during earthquake

    Kondo, M.; Kawasaki, H. [Ministry of Land, Infrastructure and Transport (Japan). Water Management and Dam Division; Sasaki, T. [Public Works Research Institute, Tsukuba (Japan). Hydraulic Engineering Research Group


    There is currently a shortage of dam sites with optimal conditions in Japan. Dam design and construction technologies must also respond to a growing demand for cost reductions and environmental concerns. Cemented Sand and Gravel (CSG) is a new dam construction material that reduces the costs of material production. However, it is not as strong as concrete. The trapezoid shape was proposed to resolve this problem, as a trapezoidal cross section can minimize stress inside the dam body and reduce fluctuations during earthquakes. This paper examines the effects of dam size and the deformability of the foundation ground on the dynamic behavior of a trapezoid-shaped CSG dam during an earthquake, as well as examining the differences between the dynamic behaviors of trapezoid-shaped CSG dams and conventional concrete gravity dams. Finite element models of both dams were used to conduct the comparison. Analysis results included stress distribution during usual loading conditions. It was concluded that stress generated inside the dam body of trapezoid-shaped CSG during earthquakes is considerably lower than concrete gravity dams with a conventional triangle shape. In addition, stress distribution inside the dam body is affected largely by the relative deformability of the foundation to CSG. 4 refs., 2 tabs.,12 figs.

  13. Landscape context and the biophysical response of rivers to dam removal in the United States

    Foley, Melissa M.; Magilligan, Francis J.; Torgersen, Christian; Major, Jon J.; Anderson, Chauncey; Connolly, Patrick J.; Wieferich, Daniel; Shafroth, Patrick B.; Evans, James E.; Infante, Dana M.; Craig, Laura


    Dams have been a fundamental part of the U.S. national agenda over the past two hundred years. Recently, however, dam removal has emerged as a strategy for addressing aging, obsolete infrastructure and more than 1,100 dams have been removed since the 1970s. However, only 130 of these removals had any ecological or geomorphic assessments, and fewer than half of those included before- and after-removal (BAR) studies. In addition, this growing, but limited collection of dam-removal studies is limited to distinct landscape settings. We conducted a meta-analysis to compare the landscape context of existing and removed dams and assessed the biophysical responses to dam removal for 63 BAR studies. The highest concentration of removed dams was in the Northeast and Upper Midwest, and most have been removed from 3rd and 4th order streams, in low-elevation (landscape settings, which limits predictive capacity in other environmental settings. Biophysical responses to dam removal varied by landscape cluster, indicating that landscape features are likely to affect biophysical responses to dam removal. However, biophysical data were not equally distributed across variables or clusters, making it difficult to determine which landscape features have the strongest effect on dam-removal response. To address the inconsistencies across dam-removal studies, we provide suggestions for prioritizing and standardizing data collection associated with dam removal activities.

  14. 77 FR 2970 - Gibson Dam Hydroelectric Company, LLC, Montana; Notice of Availability of Final Environmental...


    ... Energy Regulatory Commission Gibson Dam Hydroelectric Company, LLC, Montana; Notice of Availability of... 47897), the Office of Energy Projects has reviewed the application for license for the Gibson Dam Hydroelectric Project, located at the U.S. Department of the Interior, Bureau of Reclamation's Gibson dam on...

  15. 75 FR 81464 - Safety Zone; Columbia River, The Dalles Lock and Dam


    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Columbia River, The Dalles Lock and Dam... temporary safety zone on the waters of the Columbia River in the vicinity of The Dalles Lock and Dam while... Dalles Lock and Dam (a) Location. The following is a safety zone: All waters of the Columbia...

  16. 75 FR 30805 - Gibson Dam Hydroelectric Company, LLC; Notice Soliciting Comments, and Final Terms and Conditions...


    ... Energy Regulatory Commission Gibson Dam Hydroelectric Company, LLC; Notice Soliciting Comments, and Final... Commission and is available for public inspection. a. Type of Application: Major Project--Existing Dam. b. Project No.: P-12478-003. c. Date filed: August 28, 2009. d. Applicant: Gibson Dam Hydroelectric...

  17. 78 FR 35630 - Martin Dam Hydroelectric Project; Notice of Availability of the Draft Environmental Impact...


    ... Energy Regulatory Commission Martin Dam Hydroelectric Project; Notice of Availability of the Draft Environmental Impact Statement for the Martin Dam Hydroelectric Project and Intention To Hold Public Meetings In... reviewed the application for license for the Martin Dam Hydroelectric Project (FERC No. 349), located...

  18. 76 FR 26718 - Gibson Dam Hydroelectric Company, LLC; Notice of Availability of Draft Environmental Assessment


    ... Energy Regulatory Commission Gibson Dam Hydroelectric Company, LLC; Notice of Availability of Draft... Energy Projects has reviewed the application for license for the Gibson Dam Hydroelectric Project, located at the U.S. Department of the Interior, Bureau of Reclamation's, Gibson dam on the Sun River...

  19. 76 FR 54487 - Charter Renewal, Glen Canyon Dam Adaptive Management Work Group


    ... Bureau of Reclamation Charter Renewal, Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of... the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group... of the Glen Canyon Dam Adaptive Management Work Group is in the public interest in connection...

  20. 78 FR 54482 - Charter Renewal, Glen Canyon Dam Adaptive Management Work Group


    ... Bureau of Reclamation Charter Renewal, Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of... the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group... Canyon Dam Adaptive Management Work Group is in the public interest in connection with the performance...