Crowder S.P. Lake
Grundy County, WisconsinHypereutrophic
Crowder S.P. Lake is a 22-acre highly nutrient-loaded hypereutrophic lake in Grundy County, MO. Water quality is graded F based on 3 sampling years through 2021.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2021-09-02. 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 ft of visibility. Phosphorus level: 110 µg/L. Chlorophyll-a: 176.4 µg/L. Trophic State Index: 77.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1 ft | F |
| Phosphorus | 110 µg/L | F |
| Chlorophyll-a (Algae) | 176.4 µg/L | F |
| Trophic State Index (TSI) | 77 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 22 acres |
Location
County Ranking
Ranked #1 of 1 lakes in Grundy County
Cleaner Lakes Within 30 Miles
Crowder S.P. Lake holds Grade F. 5 nearby lakes hold higher grades.
- BNorth Bethany City ReservoirHarrison County · 24.7 mi · Two grade letters higher (F → B)
- BLake MarieMercer County · 27.7 mi · Two grade letters higher (F → B)
- DIndian Creek LakeLivingston County · 13.7 mi · Higher grade (F → D)
- DJamesport City LakeDaviess County · 10.7 mi · Higher grade (F → D)
- DLake PahoMercer County · 21.2 mi · Higher grade (F → D)
Nearby Lakes in Grundy County
More Wisconsin Lake Rankings
Other Grade F Lakes in Wisconsin
St. Louis County · Clarity: 1.6 ft
Jackson County · Clarity: 2 ft
St. Charles County · Clarity: 2.3 ft
St. Francois County · Clarity: 1.1 ft
Saline County · Clarity: 2.3 ft
Polk County · Clarity: 1.2 ft
Hypereutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Crowder S.P. Lake is a man-made reservoir impounded by the Crowder Dam (completed 1941), built primarily for recreation on the TR-THOMPSON RIVER; earth-type dam, 28 ft tall.
- Surface area
- 22 ac
- Normal storage
- 235 ac-ft
- Max storage
- 330 ac-ft
- Drainage area
- 900 sq mi
- Hazard class
- Low
- Owner
- MO. DNR PARKS
Source: USACE National Inventory of Dams, NID ID MO10378 · Operator website · Matched by proximity (0.18 km)
EPA Impairment Status
Crowder S.P. Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit MO_7135.00 · Official waterbody report · Matched by proximity (0.01 km)
Data Sources
Water quality data from the EPA Water Quality Portal
Impairment status from EPA ATTAINS 303(d) database
Grading methodology based on Metropolitan Council standards
Most recent sample: 2021-09-02
Monitoring stations: 1