Fish and Aquatic Life
Grassy Knoll Lake is a soft water, drainage lake located between Sackett Lake and Perchstein Lake on Washington Creek. The estimated normal flow of the outlet is 3.0 cubic feet per second. Severe winterkills occur occasionally. The only fish present are perch, black bullheads, white suckers, and golden shiners. The shoreline vegetation is about 50 percent tamarack and leatherleaf boa with the remainder being upland hardwood, tag alder, and cattails. The littoral bottom consists of 80 percent muck and 20 percent gravel, and supports a great variety of plant life. At least 20 species of plants are present, and they cover most of the surface of the lake. Wildlife use is high. Muskrats and beaver are usually numerous. Mallard, blue-winged teal, and wood ducks use the lakeshore for nesting and other migratory waterfowl use the lake as a feeding and resting stop. No public access is present and only one abandoned dwelling is located on the shoreline.
Source: 1970, Surface Water Resources of Taylor County Grassy Knoll Lake, T32N, R1E, Section 30 Surface Acres = 58.3, Maximum Depth = 6 feet, M.P.A. = 5 ppm, Secchi Disk = 2 feet.
Author Aquatic Biologist
Wisconsin has over 84,000 miles of streams, 15,000 lakes and milllions of acres of wetlands. Assessing the condition of this vast amount of water is challenging. The state's water monitoring program uses a media-based, cross-program approach to analyze water condition. An updated monitoring strategy (2015-2020) is now available. Compliance with Clean Water Act fishable, swimmable standards are located in the Executive Summary of Water Condition in 2018. See also the 'monitoring and projects' tab.
Wisconsin's Water Quality Standards provide qualitative and quantitative goals for waters that are protective of Fishable, Swimmable conditions [Learn more]. Waters that do not meet water quality standards are considered impaired and restoration actions are planned and carried out until the water is once again fishable and swimmable
Management goals can include creation or implementation of a Total Maximum Daily Load analysis, a Nine Key Element Plan, or other restoration work, education and outreach and more. If specific recommendations exist for this water, they will be displayed below online.
Monitoring the condition of a river, stream, or lake includes gathering physical, chemical, biological, and habitat data. Comprehensive studies often gather all these parameters in great detail, while lighter assessment events will involve sampling physical, chemical and biological data such as macroinvertebrates. Aquatic macroinvertebrates and fish communities integrate watershed or catchment condition, providing great insight into overall ecosystem health. Chemical and habitat parameters tell researchers more about human induced problems including contaminated runoff, point source dischargers, or habitat issues that foster or limit the potential of aquatic communities to thrive in a given area. Wisconsin's Water Monitoring Strategy was recenty updated.
Grants and Management Projects
|Project Name (Click for Details)||Year Started|
|WBIC||Official Waterbody Name||Station ID||Station Name||Earliest Fieldwork Date||Latest Fieldwork Date||View Station||View Data|
|1764400||Grassy Knoll Lake||10005856||Grassy Knoll Lake||8/29/2000||8/7/2012||Map||Data|
Grassy Knoll Lake is located in the Black and Little Black Rivers watershed which is 160.81 mi². Land use in the watershed is primarily wetland (32.40%), forest (30.10%) and a mix of agricultural (24.40%) and other uses (13.10%). This watershed has 211.97 stream miles, 505.95 lake acres and 23,424.34 wetland acres.
Nonpoint Source Characteristics
This watershed is ranked Low for runoff impacts on streams, Not Available for runoff impacts on lakes and Medium for runoff impacts on groundwater and therefore has an overall rank of Medium. This value can be used in ranking the watershed or individual waterbodies for grant funding under state and county programs.However, all waters are affected by diffuse pollutant sources regardless of initial water quality. Applications for specific runoff projects under state or county grant programs may be pursued. For more information, go to surface water program grants.