Elmwood Lake
Sullivan County, WisconsinEutrophic
Elmwood Lake is a 224-acre productive, nutrient-rich eutrophic lake in Sullivan County, MO. Water quality is graded F based on 3 sampling years through 2024. Compared to the 1 other monitored lakes in Sullivan County, Elmwood Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2024-07-30. 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 2.7 ft of visibility. Phosphorus level: 70.8 µg/L. Chlorophyll-a: 35.2 µg/L. Trophic State Index: 65.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.7 ft | F |
| Phosphorus | 70.8 µg/L | D |
| Chlorophyll-a (Algae) | 35.2 µg/L | F |
| Trophic State Index (TSI) | 65 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 224 acres |
Location
County Ranking
Ranked #2 of 2 lakes in Sullivan County
Cleaner Lakes Within 30 Miles
Elmwood Lake holds Grade F. 5 nearby lakes hold higher grades.
- BLake MarieMercer County · 29.3 mi · Two grade letters higher (F → B)
- BForest LakeAdair County · 24.6 mi · Two grade letters higher (F → B)
- BMilan Lake NorthSullivan County · 1.8 mi · Two grade letters higher (F → B)
- CHazel Creek Lk. LakeAdair County · 26.3 mi · Two grade letters higher (F → C)
- CForest Lake Se BranchAdair County · 25.6 mi · Two grade letters higher (F → C)
Nearby Lakes in Sullivan 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
Eutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Elmwood Lake is a man-made reservoir impounded by the Elmwood City Lake Dam (completed 1972), built primarily for water supply on the ELMWOOD BRANCH; earth-type dam, 47 ft tall and 850 ft long.
- Surface area
- 224 ac
- Normal storage
- 2,445 ac-ft
- Max storage
- 7,000 ac-ft
- Drainage area
- 6.41 sq mi
- Hazard class
- High
- Owner
- CITY OF MILAN
All listed purposes: Water Supply;Recreation.
Source: USACE National Inventory of Dams, NID ID MO10240 · Operator website · Matched by proximity (0.15 km)
EPA Impairment Status
Elmwood 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_7146.00 · Official waterbody report · Matched by proximity (1.18 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: 2024-07-30
Monitoring stations: 2