Cedar River Basin, Minnesota TMDL Study: Turbidity and Excess Nutrients wq-iw9-09a • January 2009 he Cedar River runs about 300 $10 million in Freeborn and Mower miles, from its headwaters in Dodge counties. TCounty, southern Minnesota, to Louisa County, southeastern Iowa, where it Parts of the basin also have lakes used for joins the Iowa River and then winds its recreational activities such as fishing, way to the Mississippi River. hunting and boating. Excessive nutrients In Minnesota, the Cedar River Basin Phosphorus is an consists of three watersheds: Water quality concerns essential nutrient, • Turtle Creek at 158 square miles The Cedar River Basin has several lakes but is considered a • Shell Rock River at 246 square and stream reaches (segments) listed as pollutant when it miles impaired waters by the Minnesota stimulates excessive Pollution Control Agency (MPCA), growth of aquatic • Cedar River at 435 square miles including those listed in the table below. plants or algae production. The basin spans across parts of four counties: Mower, Freeborn, Dodge and Water Body Impairment Steele. Turtle Creek Watershed Turtle Creek Turbidity Agriculture is the dominant land use in the Cedar River Watershed Cedar River Basin. The Shell Rock Two segments or Turbidity watershed has steeper slopes, while the “reaches” of the Cedar River watershed is flatter, and more Cedar River Dobbins Creek from Turbidity intensively drained. Both watersheds have East Side Lake to many small tributary streams and drainage Cedar River ditches. Shell Rock River Watershed Shell Rock River Turbidity The entire basin has experienced major Pickerel, Fountain and Excessive nutrients, hydrological changes over the decades. Albert Lea lakes namely phosphorus Turbidity Parts of the basin face serious flooding risks. For example, in the Cedar River Measures water Watershed in Mower County, the City of clarity; related to Water quality in the Cedar River Basin in Austin is located on the river at the particles in water Minnesota is also a concern for Iowa, confluence of several tributaries, (sediment and where the Cedar River is used for as a presenting significant flooding risks to the algae). Turbid, or supply for drinking water and for city and surrounding region. cloudy, water harms recreation. Iowa is conducting its own fish and wildlife, and TMDL study of the river and watershed for Major flooding occurred in the basin in thus also affects nitrate impairment. 1978, 1993, 2000 and 2004, with each recreational flood being worse than the previous. The opportunities. September 2004 flood resulted in crop losses of $7 million and property losses of wq-iw9-09a Minnesota Pollution Control Agency • 520 Lafayette Rd. N., St. Paul, MN 55155-4194 • www.pca.state.mn.us 651-296-6300 • 800-657-3864 • TTY 651-282-5332 or 800-657-3864 • Available in alternative formats watersheds. TMDL Background 2. Use computer modeling to help identify Impaired waters are those that fail to meet water quality pollutant sources, using the data collected in step standards. The federal and state governments establish one. The researchers will also model different these standards to protect specific designated uses, such scenarios for reducing pollutants. as recreation, fishing, irrigation, and support of aquatic life. 3. Write a plan, with public input, to reduce the pollutant loading to the rivers and lakes. Examples of pollutants or conditions that may place a lake or stream on the impaired waters list include 4. Implement activities to improve water quality, nutrients, bacteria, sediment, high turbidity and low such as conservation practices on farm fields and dissolved oxygen. Waters are sometimes impaired by sediment controls in urban areas. multiple pollutants. Water monitoring for the Cedar River Basin in For each impaired water, federal law requires that Minnesota began in 2008, with completion of the TMDL individual states, such as Minnesota, determine an study expected in 2011. acceptable Total Maximum Daily Load (TMDL) for the relevant pollutant(s). For more Information The TMDL process establishes the allowable level of Project Coordination pollutants for a water body based on the relationship Bev Nordby between pollutant sources and water conditions. In Mower County SWCD developing the TMDL Report, agency staff and 507-434-2603 stakeholders determine how to reduce pollutants, from both point and non-point sources, to restore water Project Leader quality to state standards. Bill Thomspon Minnesota Pollution Control Agency 507-281-7764 The process and timeline Steps in writing the Cedar River Basin TMDL include: Watershed District Web Sites Cedar River: www.cedarriverwd.org 1. Start a three-year monitoring program with field Shell Rock River: www.shellrock.org surveys to measure the levels of pollutants in, Turtle Creek www.turtlecreekwd.org and entering, streams and selected lakes in the Cedar River Basin TMDL • wq-iw9-09a • January 2009 page 2 .