Monroe City Lake B Nr. Dam
Monroe County, WisconsinLimited DataEutrophic
Monroe City Lake B Nr. Dam is a 50-acre productive, nutrient-rich eutrophic lake in Monroe County, MO. Water quality is graded C based on 1 sampling years through 2025. Compared to the 2 other monitored lakes in Monroe County, Monroe City Lake B Nr. Dam ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2025-07-28. Grade methodology: LakeGrade methodology.
Swimming Safety
Generally safe for swimming, moderate water quality
Water Quality Grade: C, Fair
No clarity data. Phosphorus level: 44 µg/L. Trophic State Index: 59.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No data | |
| Phosphorus | 44 µg/L | C |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 59 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 50 acres |
Location
County Ranking
Ranked #1 of 3 lakes in Monroe County
Nearby Lakes in Monroe County
More Wisconsin Lake Rankings
Other Grade C Lakes in Wisconsin
Warren County · Clarity: 3.8 ft
Ralls County · Clarity: 3.7 ft
Warren County · Clarity: 3.3 ft
Platte County · Clarity: 4.7 ft
Barry County · Clarity: 5 ft
Phelps County · Clarity: 4.9 ft
Eutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Monroe City Lake B Nr. Dam is a man-made reservoir impounded by the Monroe City South Lake Dam (completed 1937), built primarily for recreation on the TR.TO LITTLE INDIAN CREEK; earth-type dam, 31 ft tall.
- Surface area
- 50 ac
- Normal storage
- 217 ac-ft
- Max storage
- 829 ac-ft
- Drainage area
- 668 sq mi
- Hazard class
- High
- Owner
- CITY OF MONROE
All listed purposes: Recreation;Water Supply.
Source: USACE National Inventory of Dams, NID ID MO10538 · Operator website · Matched by proximity (0.06 km)
EPA Impairment Status
Monroe City Lake B Nr. Dam 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_7034.00 · Official waterbody report · Matched by proximity (0.46 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: 2025-07-28
Monitoring stations: 1