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Introduction <br />The Minnesota Pollution Control Agency (MPCA) conducts and <br />supports lake monitoring activities to determine if water quality <br />supports recreational uses (swimming, wading, boating, etc.) of <br />lakes, and to measure and compare regional differences and trends <br />in water quality with lakes from all over the state. MPCA staff, local <br />partners (SWCDs, watershed districts, tribal entities, etc.), and <br />citizens all play a role in sampling lake water quality. <br />As part of the MPCA's Advanced Citizen Lake Monitoring Program <br />(CLMP+), Kristen Genet, Ph. D. and her class at Anoka Ramsey <br />Community College measured water quality at Site 201 in Grass <br />Lake from May -September in 2012 & 2013. Grass Lake is 35 acres <br />in size and depth at sampling site was 1.5 meters (5 feet). Grass <br />Lake is located in the town of Ramsey in Anoka County, Minnesota. <br />CLMP+ volunteers measured water transparency, collected <br />temperature and dissolved oxygen profiles weekly, and collected <br />water chemistry samples monthly. This report provides a summary <br />of the water quality data, and of other physical and ecological <br />characteristics, of the lake (Figures 1 and 2). <br />Ecoregion and land use <br />characteristics <br />When investigating lake water quality, it is important to consider <br />how land within the lake's catchment (the area of land <br />surrounding the lake that drains water directly to it) is used. <br />Certain uses of the land increase pollutant loading to the lake. <br />For instance, phosphorus in animal waste and commercial <br />fertilizers can runoff to surface waters during heavy rain events. <br />In urban areas, runoff from impervious surfaces (roofs, <br />driveways, and roads) reaches surface waters via overland runoff <br />and storm water drainage. Additionally, phosphorus binds tightly <br />to soil, so eroded soil from developed Lakeshore or stream banks <br />is often a large source of phosphorus to lakes and streams. <br />Conversely, forested areas, undeveloped land, and wetlands are <br />important features that preserve good water quality by serving <br />as a buffer to filter water that flows across the catchment and <br />into the lake. <br />Minnesota is divided into seven ecoregions, as defined by soils, <br />land surface form, natural vegetation and current land use. Grass <br />Lake is located in the North Central Hardwood Forests (NCHF) <br />ecoregion. Throughout this report, Grass Lake characteristics are <br />compared to the typical range of values from reference lakes within the NCHF ecoregion. <br />Figure 1. Aerial photo of Grass Lake <br />0 0.1 0.2 <br />l 1 1 <br />Legend <br />KOpen Water K Rangeland <br />SIG Forest 3 Wetland <br />C=3, Cropland K Developed <br />0.4 Miles <br />Grass Lake (02-0113) • August 2014 <br />1 <br />Minnesota Pollution Control Agency <br />