Wednesday, March 4, 2009

Water Quality Standards on Mississippi - EPA Requirements for MDNR

In December 2008, US EPA informed the Missouri Department Natural Resources (MDNR) that new or revised water quality standards are necessary to protect portions of the Mississippi River in Missouri.

MDNR designated many stream segments and all of its lakes for recreational uses. However, Missouri did not assign the highest level of recreational use to a 195.5-mile segment of the Mississippi River that flows from St. Louis to the confluence of the Mississippi and Ohio Rivers. This EPA action directs the State to address approximately 160 miles of the Mississippi River to ensure that swimming, water-skiing and other recreational uses are protected. This will require MDNR to assign more stringent water quality criteria, which may in turn result in tighter wastewater discharge permit limits.

This action could impact many municipal and industrial NPDES permitted discharges in this reach of the Mississippi River, whether or not existing water quality data indicate that the river does/ does not currently meet recreational use standards.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

Caltha LLP Aquatic Toxicology / WQ Standards Services Website