Minnesota's Impaired Waters and TMDLs
Project: Kohlman Lake TMDL - Excess Nutrients
Background
This TMDL addresses excessive nutrients (phosphorus) in Kohlman Lake. Kohlman Lake is the most upstream of the four lakes that make up the Phalen Chain of Lakes in Maplewood, Little Canada, and St. Paul, Minnesota.
This TMDL project is being conducted by the Ramsey Washington Metro Watershed District in consultation with Barr Engineering, Inc. Contributors include the cities of Gem Lake, White Bear Lake, Vadnais Heights, Maplewood, North St. Paul, Little Canada, Oakdale in the watershed, and the Minnesota Pollution Control Agency.
A significant source of background information for this TMDL report is the Ramsey Washington Metro Watershed District’s Phalen Chain of Lakes Strategic Lake Management Plan (SLMP): Improvement Options and Recommendations (Barr Engineering Company, 2004) study, coupled with the follow-up studies recommended by the SLMP. The SLMP is included as an appendix to the TMDL report.
Kohlman Lake phosphorus reductions will be achieved through a series of implementation projects and programs sponsored by the Ramsey-Washington Metro Watershed District. The cities in the Kohlman Lake watershed will participate.
A TMDL implementation plan will be developed to address the phosphorus impairment within the Kohlman Lake watershed. The plan will provide a strategy of management and conservation practices necessary for the watersheds to reach water quality standards. Citizen involvement, education and outreach, and pollution prevention are key components of all TMDL implementation plans.
Map and location
Kohlman Lake is located in Maplewood in Ramsey County. The lake lies in the Mississippi RIver - Twin Cities watershed within the Upper Mississippi Drainage Basin. The watershed is in the North Central Hardwood Forests ecoregion. The lake has a surface area of 74 acres, a maximum depth of approximately 9 feet, and a mean depth of 4 feet. Most of the lake is less than 6 feet deep, with the littoral area covering the entire lake surface. Kohlman Lake is a fishing lake used primarily for motor boating, canoeing, fishing, picnicking, and aesthetic viewing. Kohlman Lake provides some limited wildlife habitat.
TMDL report and implementation plan
Fact Sheet (wq-iw11-01a)- Final TMDL (wq-iw11-01e)
- Appendix A (wq-iw11-01f)
- EPA Approval Letter (March 23, 2010) (wq-iw11-01g)
- TMDL Implementation Plan (Approved by MPCA on May 6, 2010) (wq-iw11-01c)
Other documents
None.
Meetings and events
None.
Links
Information contact
Roger Ramthun
TMDL Project Manager
Minnesota Pollution Control Agency
520 Lafayette Road
St. Paul, MN 55155
651-757-2663
roger.ramthun@state.mn.us