Lake Darling Max Depth
Washington County, WisconsinHypereutrophic
Lake Darling Max Depth is a 304-acre highly nutrient-loaded hypereutrophic lake in Washington County, IA. Water quality is graded F based on 2 sampling years through 2024.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2024-08-26. 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: 60.5 µg/L. Trophic State Index: 71.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.6 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 60.5 µg/L | F |
| Trophic State Index (TSI) | 71 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 304 acres |
Location
County Ranking
Ranked #1 of 1 lakes in Washington County
Cleaner Lakes Within 30 Miles
Lake Darling Max Depth holds Grade F. One nearby lake has a higher grade.
See full comparison →Nearby Lakes in Washington County
More Wisconsin Lake Rankings
Other Grade F Lakes in Wisconsin
Hypereutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Lake Darling Max Depth is a man-made reservoir impounded by the Lake Darling Dam (completed 1950), built primarily for recreation on the HONEY CREEK; earth-type dam, 47 ft tall and 1,230 ft long.
- Surface area
- 304 ac
- Normal storage
- 3,154 ac-ft
- Max storage
- 9,823 ac-ft
- Drainage area
- 19.64 sq mi
- Hazard class
- Significant
- Owner
- Iowa Department of Natural Resources
Source: USACE National Inventory of Dams, NID ID IA01381 · Operator website · Matched by proximity (0.2 km)
EPA Impairment Status
Lake Darling Max Depth is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit IA 03-SKU-924 · Official waterbody report · Matched by proximity (1.1 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: 2024-08-26
Monitoring stations: 1