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Showing 1 to 15 of 15 for “"TMDLs"”.
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An Examination of the Reference Watershed Approach for TMDLs with Benthic Impairments
This research addresses the Reference Watershed Approach (RWA) in the TMDL process for benthic impairments. In the RWA, do different land use sources (DOQQ and NLCD) or use of alternative water quality models (GWLF and SWAT) result in different stressor loadings? Is there a difference in stressor …
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Comparing Two Methods for Developing Local Sediment TMDLs to Address Benthic Impairments
… either the RWA or the DM for developing sediment TMDLs. Those issues are discussed in detail. Recommendations the need for further studies, based in questions raised by the research presented here are also discussed.
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Evaluation of the Development and Effectiveness of Copper Total Maximum Daily Loads (Tmdls) to Achieve Marine Water Quality Criteria
… agencies establish Total Maximum Daily Loads (TMDLs) to reduce concentrations of toxic chemicals from entering waterways. A TMDL determines the maximum amount of pollutant loading a water body can sustain and still achieve water quality standards; they are developed to ensure that surface water …
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Turbidity and Nutrient Response to Storm Events in the Wissahickon Creek, Suburban Philadelphia, PA
… and nutrients. Total Maximum Daily Loads (TMDLs) were implemented in 2003 for nutrients (NO3-, PO43-, NO2-, and CBOD5) and siltation. A new TMDL for total phosphorus (TP) was proposed in 2015, despite minimal data on the effectiveness of the 2003 TMDLs. This new proposal was met with …
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An Investigation of the Relationships Between Stream Benthic Macroinvertebrate Assemblage Conditions and Their Stressors
… of the study results for development of benthic TMDLs. A procedure to determine the relationships between stressors and benthic macroinvertebrate assemblage conditions was developed. Existing data on sediment, habitat, water quality, landuse, watershed characteristics, livestock numbers, and …
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Comparing Alternative Methods of Simulating Bacteria Concentrations with HSPF Under Low-Flow Conditions
… Virginia watersheds where bacterial impairment TMDLs had been previously developed and where low-flow conditions had been encountered. The three methods; Flow Stagnation (FS), DD Stage Cut-off (SC), and Stream Reach Surface Area (SA), have all been used previously to develop TMDLs. A modified …
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Performance Analysis of the Ashby Stormwater Retention Pond in Fairfax City, Virginia
… existing and future water quality goals set by TMDLs, it must be proven that such ponds truly provide the water quality benefits for which they have been credited. The inflow and outflow water quality of Ashby Pond was examined over 7 months from fall 2012 to spring 2013. During that period, the …
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Biophysical economic analysis of nutrient and sediment management practices in the Mississippi Alluvial Valley
… address future total maximum daily loads (TMDLs) for the Cabin-Teele sub-watershed, within the lower Mississippi River Basin. The dissertation had two objectives. The first objective was to examine the economic and environmental impact of tillage and nutrient management practices in …
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Neoliberalism, the Environmental Protection Agency, and the Chesapeake Bay
… legitimizes pollution-causing behavior through TMDLs. Further, the act was weakened by neoliberal forces with the non-point source exemption created for the sake of avoiding economic harm to large industries and its shortcomings are visible within many of the nation's waterways, including the …
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Examining the Influence of Wildlife Population and Fecal Coliform Density Variability on Virginia Bacterial TMDL Development
… water quality impairment in Virginia. Bacteria TMDLs (Total Maximum Daily Loads) for watersheds are typically created using a modeling approach. These models require characterization of all residential, agricultural, and wildlife sources of bacteria. Wildlife bacteria source characterization is …
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Potential and Quantification of Street Sweeping Pollutant Reductions towards addressing TMDL WLAs for MS4 Compliance
… (WLAs) and meet total maximum daily loads (TMDLs). Street sweeping is potentially an effective BMP since streets exist throughout urban watersheds, often are directly connected to the storm sewer, and are found to contain an abundance of contaminants. Although pollutant removal from street …
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Improving microbial fate and transport modeling to support TMDL development in an urban watershed
… can be can be readily integrated into existing TMDLs. As even small concentrations of FIB from human sources are associated with great risk, and monitoring efforts indicated moderate/high levels of human-associated MST marker in this watershed, remediation efforts to protect public health would …
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Identifying Sources of Fecal Pollution in the Appomattox River Watershed
… of bacterial Total Maximum Daily Loads (TMDLs). The Appomattox River watershed is primarily undeveloped with 70.8% of the land forested, 17.0% used for agriculture (mainly livestock production), and 7.7% classified as water, wetland or barren land. The remaining 4.5% is developed for …
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Modeling the Effects of Acid Deposition and Natural Organic Acids on Surface Waters
… loads (CLs) and Total Maximum Daily Loads (TMDLs) to project reductions in atmospheric deposition loads that would provide healthy conditions for the fisheries of surface waters in these regions. These concepts are commonly used as tools for communication between scientists and policy …
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Partitioning Between Soil-Adsorbed and Planktonic Escherichia coli
A scarcity of comparable research on the transport of bacteria has forced hydrologic models to assume that bacteria travel as dissolved chemicals. In reality, most bacteria preferentially attach to soil aggregates, and behave very differently from planktonic bacteria. The goal of this research …