Water Quality Assessment and Impaired Waters

Section 303(d) Streams and Lakes

Section 303(d) of the federal Clean Water Act requires that each state identify waters that are not meeting water quality standards and for which adequate water pollution controls have not been required. Water quality standards protect such beneficial uses of water as whole body contact (such as swimming), maintaining fish and other aquatic life, and providing drinking water for people, livestock and wildlife. The 303(d) list helps state and federal agencies keep track of waters that are impaired but not addressed by normal water pollution control programs. More info

Missouri Water Quality Report

The 305(b) Report is a summary of water quality in Missouri. It assesses how well the waters of the state are meeting national Clean Water Act goals. The report also contains maps showing what waters in the state are impaired, what pollutants affect them and the sources of those pollutants. More info...

Water Quality Standards

Water Quality Standards (WQS) are the foundation of the Clean Water Act. In Missouri, the standards define the water quality goals for a waterbody by designating its beneficial uses. WQS also set maximum allowable concentrations for up to 100 or more contaminants for each of those beneficial uses. Missouri's water quality standards name (and give locations for) over 3600 stream segments and more than 450 lakes. The standards also give the beneficial uses for each of those waters. The standards provide a very detailed set of water quality goals for streams and lakes in Missouri. All of Missouri's water quality management activities such as issuance and enforcement of discharge permits, inspection of wastewater and storm water treatment facilities, providing technical assistance in wastewater or storm water control and providing financial assistance in building and maintaining wastewater treatment facilities, are focused on meeting water quality standards. More info...

Total Maximum Daily Loads

One of the tools we use to protect our water quality is a TMDL study. That stands for the Total Maximum Daily Load calculation of the maximum amount of a given pollutant a waterbody can absorb before its quality is affected. That sounds like a mouthful, but think of it like this; when you don’t feel well, you often take your temperature. If it’s above 98.6 you generally take steps to bring your fever down to normal. A TMDL works the same way. It tells us something is wrong with a body of water and indicates a course of treatment to fix the problem. More info...