Minnesota's Impaired Waters and TMDLs
TMDL Project: Lake Crystal — Excess Nutrients
Background
Lake Crystal blue-green algae bloom, September 9, 2004.
Lake Crystal blue-green algae bloom,
June 13, 2007.
Crystal Lake, a portion of the Crystal, Loon and Mills lake watershed, was listed on the 303d impaired waters list for excess nutrients in 2006. This listing was the result of previous monitoring data, investigative projects, and local support following toxic blue-green algae blooms in the fall of 2004. Minnesota Pollution Control Agency staff reported a concentration of microcystin, a blue-green algae toxin at 7190 ug/L. The acceptable exposure levels based on the World Health Organizations is 1.0ug/L.
Crystal Lake is 355 acres, with a contributing watershed of 15,900 acres. Based on the 1990 land use inventory, approximately 77 percent of the watershed is used for agriculture. This watershed has significant local importance, as it is a popular recreational area and also contains the city of Lake Crystal.
Crystal Lake receives surface water from two primary sources, County Ditch 56 and the outlet of Loon Lake. The study found County Ditch 56 to be a major contributor of nutrients and sediment to Crystal Lake. Ditch 56 drains agricultural land to the southwest of Lake Crystal and a portion of the city of Lake Crystal before discharging into the lake.
The TMDL program provides a cooperative approach where MPCA can assist the Water Resources Center at Mankato and the city of Lake Crystal in upgrading data collection, analysis and TMDL development operations. This project will also work in conjunction with the current Clean Water Partnership which is actively working toward reducing nutrient input from various areas of the watershed. The work plan for the TMDL has been completed, with ongoing monitoring continuing though 2009. Citizens within the area are invited to upcoming meetings to discuss the project and future work to be done. A citizen stakeholder group is still being developed.
Map and location
Lake Crystal is part of the Crystal Loon Mills watershed. Crystal Loon Mills watershed is located in Blue Earth County in the Minnesota River - Mankato watershed in the Minnesota River basin.;
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Map of Lake Crystal within the Minnesota River Basin (tmdl-mn-lakes-06)
TMDL report and implementation plan
- Draft TMDL (wq-iw7-37b)
- Public Notice open for comment August 27, 2012 – September 26, 2012
- Comments on the Draft TMDL for Lake Crystal — Excess Nutrients (wq-iw7-37n)
Other documents and online information
Factsheets:
Nutrients: Phosphorus, Nitrogen Sources, Impact on Water Quality- Assessing and Listing Impaired Waters
- Background on Total Maximum Daily Loads
- Minnesota Water Story — Technology helps farmers protect water quality
- Minnesota River — Mankato watershed
Meetings and events
See the TMDL Meetings, Events and News page for notices of general interest and event-related information on impaired waters/TMDLs.
Links
Information contact
Paul Davis, Project Manager
Minnesota Pollution Control Agency
12 Civic Center Plaza, Suite 2165
Mankato MN 56001
507-344-5246
Scott Bohling
Water Resources Center, MSUM
184 Trafton Science Center, South
Mankato, MN 56001
507-389-2355
