Red Rock Lake
Located in Eden Prairie, Red Rock Lake is a part of the Purgatory Creek chain of lakes. During high water events it outflows through an overflow pipe to Staring Lake.
Lake size: 121 acres
Watershed size: 1,286 acres
Average depth: 4.7 ft
Maximum depth: 19 ft
DNR - Red Rock Lake depth mapDNR Shoreland classification: Recreational Development
MPCA classification: Shallow lake (average depth less than 15 feet)
MPCA Impaired Waters status: Impaired for mercury in fish tissue; Delisted for nutrients in 2016
Invasive species: Curlyleaf Pondweed, Purple Loosestrife
Water Quality
Red Rock Lake is classified as a “Shallow Lake” by the MPCA. To be considered healthy, the lake must have very low average phosphorus and chlorophyll-a levels and an average water clarity of 1.0 meters (3.3 feet) or greater.
From June through September every year, District staff visit this and other lakes every two weeks to collect water samples and take readings. Samples are sent to a laboratory to be tested for nutrients and other compounds. Staff also measure water clarity by lowering a Secchi disk into the water and measuring how deep it goes before it is no longer visible. The data indicates the lake’s health based on standards set by the MPCA.
Lake Grade
RPBCWD staff assigned this letter grade to the lake based upon how well it is meeting water quality goals. Learn more about lake water quality grades.
For more information about the water quality and grades for lakes monitored in the District, visit the lake factsheets page.
For more information about waterbody impairments, visit the Minnesota's Impaired Waters List webpage managed by the Minnesota Pollution Control Agency.
