Cedar Lake
Madison County, WisconsinHypereutrophic
Cedar Lake is a 84-acre highly nutrient-loaded hypereutrophic lake in Madison County, IA. Water quality is graded F based on 2 sampling years through 2022. Compared to the 1 other monitored lakes in Madison County, Cedar Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2022-09-07. Grade methodology: LakeGrade methodology.
Swimming Safety
Avoid swimming, very poor water quality, potential algae toxins
Water Quality Grade: F, Very Poor
Very murky, less than 1.6 ft of visibility. Chlorophyll-a: 62.7 µg/L. Trophic State Index: 71.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.6 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 62.7 µg/L | F |
| Trophic State Index (TSI) | 71 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 84 acres |
Location
County Ranking
Ranked #2 of 2 lakes in Madison County
Cleaner Lakes Within 30 Miles
Cedar Lake holds Grade F. 2 nearby lakes hold higher grades.
- BDale Maffitt ReservoirDallas County · 14.6 mi · Two grade letters higher (F → B)
- DHooper Pond LakeWarren County · 22 mi · Higher grade (F → D)
Nearby Lakes in Madison County
More Wisconsin Lake Rankings
Other Grade F Lakes in Wisconsin
Hypereutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Cedar Lake is a man-made reservoir impounded by the Cedar Creek Dam (completed 1939), built primarily for water supply on the TR-CEDAR CREEK; earth-type dam, 50 ft tall and 860 ft long.
- Surface area
- 84 ac
- Normal storage
- 935 ac-ft
- Max storage
- 1,820 ac-ft
- Drainage area
- 16.72 sq mi
- Hazard class
- Significant
- Owner
- Winterset Water Works
Source: USACE National Inventory of Dams, NID ID IA01360 · Operator website · Matched by proximity (0.19 km)
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2022-09-07
Monitoring stations: 1