National Lakes Assessment Project (NLAP)
Minnesota’s participation in the U.S. Environmental Protection Agency’s (USEPA) 2012 NLA involved a collaborative approach that included USEPA, U.S. Forest Service (USFS), MN Department of Natural Resources (MDNR), MN Department of Health (MDH), MN Department of Agriculture (MDA) and the Red Lake and White Earth Native American Bands. A total of 1,000 lakes was included in the national survey. Minnesota drew 42 lakes as a part of the initial draw for this statistically based national survey effort and added 8 lakes to allow for state-based assessment. All 50 lakes received the national level of assessment and contributed to both the state-based and national assessments. In addition, 100 lakes were added from USEPA’s randomized list of lakes to allow for ecoregion-based assessments (50 per major ecoregion) in Minnesota.
This collaboration and the various survey add-ons were the basis for several “value-added” topics.
- Emerging contaminant analysis in 50 lakes (MPCA)
- Pesticide analysis in 50 lakes and triazine analysis in all 150 lakes (MDA)
- Zooplankton analysis in all 150 lakes (MDNR)
- Blue-green algal toxin (microcystin) in all 150 lakes (lab analysis by MDH, reporting by MPCA)
- Water chemistry and profiles in all 150 lakes, including comparisons among 2007 and 2012 results (MPCA)
NLA 2012 statewide reports
A series of reports is being drafted based on the 2012 NLA. These reports or their links will be posted here as they are completed.
- Overview of Minnesota’s 2012 Survey
MPCA’s plan to sample 150 lakes as a part of the 2012 NLA was ambitious. Weather conditions in summer 2012 were challenging and included record rainfall events in June and transitioned to severe drought over much of the state by mid-summer. This resulted in numerous lakes being dry or too shallow to sample over much of the state.
- Pharmaceuticals and Endocrine Active Chemicals in Minnesota Lakes
Many previous studies have established that a variety of pharmaceuticals, personal care products (PPCPs), and other chemicals are commonly detected at low concentration in rivers and lakes. However, this was the first study to analyze this suite of chemicals in randomly-selected lakes. Forty-seven of the 50 lakes sampled had at least one of the chemicals that were tested for. The insect repellent DEET was found in 76 percent of the lakes sampled, making this chemical the most frequently discovered.
- Pesticides in Minnesota lakes (Minn. Dept of Agriculture)
Minnesota was the only state in the 2012 NLA to include comprehensive testing for pesticides as a part of the study. Fifty-two lakes were analyzed using the MDA laboratory’s gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) advanced methods for 132 different pesticide compounds. Nineteen different pesticide compounds were detected, with atrazine being discovered most frequently in 67 percent of samples. A comparison of 2012 and 2007 pesticide data notes a decrease in the detection frequency of atrazine and related compounds.
- Zooplankton communities in Minnesota lakes
As a part of the 2012 National Lakes Assessment, zooplankton were sampled in 149 randomly selected lakes across Minnesota. Laboratory identification, data analysis, and reporting were conducted by the Department of Natural Resources. These data provided a unique opportunity to describe zooplankton communities in Minnesota at a statewide and ecoregion basis and as a function of nutrient enrichment. Results from this work contribute to our understanding of the ecology of Minnesota’s lakes.
- National, state, and ecoregion-based approach
The MPCA partnered with several state agencies, Native American bands, and federal agencies to conduct the 2012 National Lakes Assessment for Minnesota. Several reports have been completed, while others are underway. This PowerPoint, presented at the October 2014 Minnesota Water Resources Conference, provides an overview of the survey and provides examples of how this data is used at the national, state, and ecoregion scales for describing lake condition.
- Aquatic macrophyte assessments
Aquatic plants are an essential part of the overall ecology of lakes. The 2012 NLA included rapid assessment of aquatic plant communities at randomized sites in the nearshore area of study lakes nationwide. This report shares findings for 50 Minnesota lakes and makes recommendations for modifying the assessment method in the 2017 NLA. (April 2015)
- Water chemistry, lake morphometry, and watershed characteristics
Minnesota has among the most diverse population of lakes in the U.S. The randomized 2012 data of the National Lakes Assessment provide a detailed look at lake and watershed characteristics, water chemistry, and physical measurements for Minnesota lakes. Regional patterns and statistical summaries provide a comprehensive description of Minnesota’s lake resource and contribute to its management. (May 2015)
- Analysis of physical habitat condition indices
The complexity and extent of near-shore riparian natural vegetation, woody debris and substrates influence the health of aquatic and terrestrial animal communities. Nearshore habitat assessments in the 2007 and 2012 NLA surveys were used to determine the health of shoreland areas in Minnesota lakes. Among the findings in this study was that Minnesota lakes were in significantly better shape with regard to the degree of human disturbance than Michigan and Wisconsin lakes. (May 2015)
These brief reports summarize data for one or more lakes that were included in the study. These reports are prepared as a service to study collaborators, including property owners that have granted access to the lakes. This page will be populated as reports are created.
- Lakes on the White Earth Reservation
- Lakes on the Red Lake Reservation
- Lakes in Tamarac Wildlife Refuge
- Lakes in Northeastern Minnesota
For more details on the national study: National Lakes Assessment (U.S. EPA)
For additional information about this project, please contact Steve Heiskary at 651-757-2419, or toll-free at 800-657-3864.
NLAP archived statewide reports
This report series examines statewide patterns in various chemical, physical and biological parameters based on data collected during the NLAP survey.
- Microcystin Concentrations in Minnesota Lakes
- Aquatic Macrophytes in Minnesota Lakes
- Water mercury concentrations in Minnesota lakes
- Fish-based Index of Biotic Integrity (IBI) for Minnesota lakes
- Pesticides in Minnesota Lakes  (Minn. Dept. of Agriculture)
- An overview of water chemistry in Minnesota lakes
NLAP archived survey reports for select Minnesota lakes
These lake information sheets contain a brief description of each lake sampled for the Environmental Protection Agency National Lake Assessment Program: general information about lake area and depth, watershed area and land use composition, lake dissolved oxygen and temperature profiles, and water quality data from the survey. The typical range of water quality values for each ecoregion is provided as a basis for comparison. Data tables will be periodically updated as more data becomes available.
|Blue Earth||Eagle (North)|
|Crow Wing||Crow Wing|
|Itasca||Long (Main Bay)|
|Le Sueur||Upper Sakatah|
|Otter Tail||West Leaf|
|Otter Tail||Maine (Round)|