Birch Lake Quick Facts
Lake Size: 32 acres
Watershed Drainage Area: 1,890 acres; land cover includes wetland, forest, cropland and grassland.
Maximum Depth: 8 ft.
Outlet Elevation: 894.5 ft.
Low Water Level: N/A
High Water Level: N/A
Impairments: Not listed as impaired (does not qualify as a lake)
Invasive Species (2018): curly-leaf pondweed
Water Quality 2021 Data
Lake Grade: C
Summer avg tot. phosphorus 71.8 μg/L
Summer average Secchi disc: 5.4 ft
Summer chlorophyll-a: 10.4 μg/L
10-Year (2031) Goals
- Reduce the 5-year mean phosphorus concentration (Average) to less than or equal to 60 μg/L.
- Improve the mean sechhi depth to greater than or equal to 3.3 ft.
- Identify a 10-year mean bottom water chloride level of less than of equal to 230 mg/L.
- Increase the percentage of parcels with greater than or equal to 75% natural shoreline.
Birch Lake has a surface area of 32 acres and is two miles downstream of Bone Lake. Nielsen Lake's landlocked watershed discharges groundwater flow towards Birch Lake. Birch Lake is considered a shallow lake or wetland with 100% littoral area shallow enough to support emergent and submerged aquatic plants. Birch Lake is identified in name as a lake but was determined by the State to be a wetland due to its physical characteristics. Therefore it is not listed for a water quality impairment. The lake has been identified by CLFLWD to be a key factor influencing the water quality of School Lake and Little Comfort Lake. A survey in 2008 identified a diverse plant population in Birch Lake with little curly-leaf pondweed present.