Marais des Cygnes Basin TMDLs

• TMDLs for the Marais des Cygnes Basin
• Implementation Priority
• Approval Letter

The Section 303(d) list submitted to and approved by EPA in 1998, identifies 86 river segments and 13 lakes in the Marais des Cygnes River Basin as water quality impaired. Among the streams, the greatest number of impairments were caused by excessive levels of fecal coliform bacteria and dissolved oxygen depletion. Among the lakes, eutrophic conditions indicative of excessive algae production was the predominant cause of impairment.

Other pollutants limiting the use of the Marais des Cygnes River Basin streams include nutrients oxygen demand, selenium and ammonia. Additional lake impairments were caused by dissolved oxygen depletion, pH, excessive aquatic plants, atrazine, and siltation. Each parameter causing impairment requires a TMDL.

Many of the stream segments, configured in a watershed setting, will have a TMDL applied to them as a whole. Thirteen watershed and 17 lake TMDLs will be developed. The TMDLs describing the goals to reduce pollution and achieve water quality standards and the plans to meet those goals were submitted to EPA on June 28, 2001 and approved on August 28, 2001.