Lake Water Quality Assessment

The Minnesota Pollution Control Agency has conducted assessments of lake water quality for over 3,100 lakes. Lake water quality assessments were first required by the Federal Water Quality Act of 1987, with biennial or annual assessments conducted since that time. Starting in 2010, annual assessments are conducted on a rotating watershed basis, and reports are written that summarize results for all assessed lakes in a given watershed.

As a part of MPCA’s lake assessment efforts, numerous studies that document the condition of lakes across Minnesota have been conducted. Many of these studies were conducted in collaboration with lake associations, county coalitions, Minnesota Department of Natural Resources and various other partners and have been referred to as Lake Assessment Program (LAP) reports. Detailed reports on lake and watershed condition and trends are developed as a part of these studies. Since 1985, over 200 LAP studies have been conducted. In addition to complete LAP studies, the MPCA has conducted a variety of other lake monitoring (regional and trend studies) efforts that result in a variety of reports. These include the following:

• “Trend” reports are often follow-up studies to previously conducted LAP or other studies. Their primary focus is to assess trends in lake condition over time.
• “Notes” reports, as they are referred to, are brief LAP-like reports often prepared in response to lakeshore residents' concerns or as a part of oral presentations. These brief reports often focus primarily on the current trophic status of the lake.
• “Status” reports are brief reports that serve to characterize the trophic status and trends of several lakes in a county.
• “CLMP+” was initiated in 2001 and represents advanced monitoring for Citizen Lake Monitoring Program (CLMP) volunteers.  These studies are typically conducted in cooperation with county local water planning offices.

Below are some of the more recent lake assessment reports and following is a listing of all available LAP and related reports sorted by county. The spreadsheet includes the name of the lake, the Minnesota Department of Natural Resources lake identification number, year the study was conducted and the type of report.

In addition to lake or watershed specific studies a variety of research studies have been conducted as a part of MPCA’s LWQA. This research addresses specific issues such as the extent of blue-green algal toxins in Minnesota lakes, ecology and water quality of shallow lakes, determining lake trends based on sediment cores and providing support for development of lake eutrophication standards. Below are some of the more current studies that have been conducted. The spreadsheet that follows includes other reports developed as a part of lake water quality assessments.