Surface Water Quality Assessments
The Brookings Area TMDL Sampling Project was a one year sampling project that began in the Spring of 2012, and then extended an additional year.
The project involved sampling 10 storm sewer locations within the City of Brookings, two sites on Six Mile Creek, and one site on the Big Sioux River. The
sites were monitored for water quality (sediment and bacteria), stage, and discharge during > 0.10 inche rain events. The stormwater outflows in the
southern part of Brookings, flow through constructed wetlands before entering waterways. The study showed lower bacteria and sediment concentrations from
these areas. The monitoring location on Six Mile Creek (above Brookings) showed higher concentrations of bacteria and sediment than at the monitoring
location on Six Mile Creek below Brookings. A follow-up study in 2015, determined the drop in pollutant levels between the two monitoring sites on Six Mile
Creek were due to the creek itself flowing through the South Dakota State University ponds just northwest of Brookings. These ponds are acting as a filter and
reducing the pollutants in Six Mile Creek as it flows through. For further information about this project, contact Andrew Kopp with the SD DENR.
The East Dakota Water Quality Monitoring Project was a two year project that began in the Fall of 2009. The project involved installing 22
permanent stream level recorders at state ambient WQM monitoring sites on the Big Sioux, Vermillion, and Minnesota Rivers and collecting stage and discharge
measurements at those sites. This effort was critical to long-term monitoring efforts and provides a continuous record of stage to discharge
relationships that will aid in making management decisions and developing restoration plans in the future. For more information on this project, contact the
District Manager, Jay Gilbertson.
Central Big Sioux River Watershed Assessment Project (1999-2003)
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. Phase II Implementation is currently in progress.
The Nitrate Monitoring Project began in 2015, due to a growing public concern in South Dakota and surrounding states regarding nitrate contamination of
drinking water sources. Numerous public water systems in Iowa and Minnesota are dealing with nitrate concentrations in source waters that exceed acceptable
levels. The District began an intesive program of testing for nitrates in the Big Sioux River from its headwaters to the confluence with the Missouri River.
Samples are collected April through November at 28 sites along the Big Siouix River and 12 sites on major tributaries entering the river. Depending on the site,
weekly or bi-weekly samples are being collected. For more information about this project, contact the District Manager, Jay Gilbertson.
Other Assessment Projects: