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Watershed Assessments |
The Central Big Sioux River Watershed Assessment Project began in April of 1999 and lasted through December of 2003 when data analysis and compilation into a final report was completed. The assessment was conducted as a result of several segments of the Big Sioux River being identified as impaired in the 1998 South Dakota 303(d) Impaired Water Body List. Excessive fecal coliform bacteria and total suspended solids were cited as the primary problems in this area. An Environmental Protection Agency (EPA) Section 319 grant provided a majority of the funding for this project. The South Dakota Department of Environment and Natural Resources (SD DENR) and the East Dakota Water Development District (EDWDD) provided matching funds for the project. The assessment focused on the central portion of the Big Sioux River (BSR) and its major tributaries between the communities of Volga and Brandon. Water quality monitoring and watershed modeling of the 1.2 million acre area spanning Brookings, Lake, Moody and Minnehaha Counties resulted in the identification of several sources of impairment not only in the BSR but also in many of the major tributaries joining the river. Recommendations for improving water quality in these areas included implementing Best Management Practices (BMPs) and construction of several waste management systems at animal feeding operations. The SD DENR and EDWDD have also been in contact with the Minnesota Pollution Control Agency to address impaired streams draining Minnesota land. The long term goal of this assessment was to locate and document sources of non-point source pollution in the watershed and provide feasible restoration alternatives to improve water quality within the watershed. A final assessment report with attached Total Maximum Daily Load Reports (TMDLs) for each waterbody and impairment can be viewed here. EPA approved TMDL list for this project can be viewed here. The final report has been completed and has been published by the SD Department of Environment and Natural Resources. A printed copy can be requested from the Department of Environment and Natural Resources in Pierre. Phase II Implementation is currently in progress. For more information see the Big Sioux Watershed Project section. The North-Central Big Sioux River Watershed Assessment Project began in April of 2001 and continued through December of 2005 when data analysis and compilation into a final report was completed. The assessment was conducted as a result of several segments of the Big Sioux River being identified as impaired in the 1998 South Dakota 303(d) Impaired Water Body List. Total suspended solids were cited as the primary problem in this area. An EPA Section 319 grant provided a majority of the funding for this project. The SD DENR and the EDWDD provided matching funds for the project. The assessment focused on the north-central portion of the Big Sioux River (BSR) and its major tributaries between the communities of Watertown and Volga. Water quality monitoring and watershed modeling of the 500,000 acre area spanning Brookings, Hamlin, Deuel and Codington Counties resulted in the identification of several sources of impairment not only in the BSR but also in the major tributaries joining the river. Recommendations for improving water quality in these areas included implementing BMPs and construction of waste management systems at animal feeding operations. The long term goal of this assessment was to locate and document sources of non-point source pollution in the watershed and provide feasible restoration alternatives to improve water quality within the watershed. A final assessment report with attached TMDLs for each waterbody and impairment can be viewed here. EPA approved TMDL list for this project can be viewed here. The final report has been completed and has been published by the SD Department of Environment and Natural Resources. A printed copy can be requested the Department of Environment and Natural Resources in Pierre. The Oakwood Lakes Watershed Assessment Project began in April of 2001 in conjunction with the North-Central Big Sioux River Watershed Assessment Project. This assessment continued through December of 2005 when data analysis and compilation into a final report was completed. The Oakwood Lakes watershed assessment was conducted as a result of East Oakwood Lake being placed on the 1998 South Dakota 303(d) Impaired Waterbody List due to excess nutrients, siltation, and noxious aquatic plants. Additionally, West Oakwood Lake was listed on the 2002 South Dakota 303(d) Impaired Waterbody List for not supporting its beneficial uses due to Trophic State Index (TSI) impairment. Both East Oakwood Lake and West Oakwood Lake have been identified as impaired on subsequent impaired waterbody lists to include the most recent 2006 South Dakota Integrated Report for Surface Water Quality Assessment. An EPA Section 319 grant provided a majority of the funding for this project. The SD DENR and the EDWDD provided matching funds for the project. Water quality monitoring and watershed modeling of the 55,000 acre watershed located in Brookings County resulted in the identification of nutrient impairment as related to TSI trend in both East Oakwood Lake and West Oakwood Lake. There were also a number of pH exceedences identified in East Oakwood Lake. The sources of these impairments may be addressed through BMPs such as shoreline buffers, riparian management, and in-lake management of rough fish biomass. The long term goal of this assessment was to locate and document sources of non-point source pollution in the watershed and provide feasible restoration alternatives to improve water quality. A final assessment report with attached TMDLs for each waterbody and impairment can be viewed here. The final report has been completed and has been published by the SD Department of Environment and Natural Resources. A printed copy can be requested from the Department of Environment and Natural Resources in Pierre. The School Lake Watershed Assessment Project began in March of 2003 and lasted through August of 2005, when data analysis and compilation into a final report was completed. The assessment was conducted as a result of School Lake being placed on the 1998 South Dakota Report 303(d) Impaired Waterbody List due to excess nutrients, siltation, and noxious aquatic plants. The lake has been identified as impaired on subsequent impaired waterbody lists to include the most recent 2006 South Dakota Integrated Report for Surface Water Quality Assessment for not supporting its beneficial uses due to TSI impairment. An EPA Section 106 grant provided a majority of the funding for this project and the SD DENR and the EDWDD provided matching funds. Water quality monitoring and watershed modeling of the 22,000 acre watershed located in northwest Deuel County resulted in the identification of nutrient impairments in School Lake and Bullhead Lake. There were also a number of pH exceedences identified in School Lake, Bullhead Lake, and Round Lake. The sources of these impairments may be addressed through BMPs such as shoreline buffers and riparian management, as well as in-lake management of nuisance algae and rough fish removal. The long term goal for this project was to locate and document the sources of non-point source pollution in the School Lake Watershed and provide feasible restoration alternatives for the improvement of water quality. A final assessment report with attached TMDLs for each waterbody and impairment can be viewed here. The 30-day public notice period of this assessment and its TMDLs ended November 2006. The State is currently in the process of officially publishing these documents. A copy of the presentation made to the South Dakota Non-point Source Task Force in March 2007 is located here. The Lake Campbell Watershed Post-Assessment Project began in April of 2007 and concluded with a final report December 31, 2008. This assessment was conducted to compare historical watershed conditions and present-day conditions of the lake and its watershed. Lake Campbell was initially identified in the 1996 South Dakota Report to Congress 305(b) Water Quality Assessment as being hypereutrophic due to excessive nutrients, siltation, and noxious aquatic plants. Since that time, it has been listed as impaired in subsequent reports as well as listed on the South Dakota 303(d) Waterbody Lists. Lake Campbell was most recently identified in the 2006 Integrated Report for Surface Water Quality Assessment for TMDL development due to TSI trend and not supporting of its Warmwater Marginal Fish Life Propagation beneficial use. Water quality monitoring and watershed modeling of the 118,000 acre watershed spanning across Brookings, Lake, Kingsbury, and Moody Counties shows the lake is meeting all of its water quality standards for its assigned beneficial uses. Results also show that more improvements are needed in order for Lake Campbell to attain its recommended Trophic State Index goal of 68.4. This means the lake still contains excessive nutrients even though it is meeting all of its water quality criteria for a Warmwater Marginal Fishery. The final report has been completed and has been published by the SD Department of Environment and Natural Resources. A printed copy can be requested from the East Dakota Water Development District in Brookings or from the Department of Environment and Natural Resources in Pierre. |