Lake Tschida
Grant County, WisconsinEutrophic
Lake Tschida is a 10,953-acre productive, nutrient-rich eutrophic lake in Grant County, ND. Water quality is graded C based on 2 sampling years through 2025. Compared to the 5 other monitored lakes in Grant County, Lake Tschida ranks #3 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2025-09-18. Grade methodology: LakeGrade methodology.
Swimming Safety
Generally safe for swimming, moderate water quality
Water Quality Grade: C, Fair
Murky, only visible to about 5.2 ft. Chlorophyll-a: 6.1 µg/L. Trophic State Index: 51.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 5.2 ft | D |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 6.1 µg/L | B |
| Trophic State Index (TSI) | 51 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 11.0K acres |
Location
County Ranking
Ranked #3 of 6 lakes in Grant County
Nearby Lakes in Grant County
More Wisconsin Lake Rankings
Other Grade C Lakes in Wisconsin
Eutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Lake Tschida is a man-made reservoir impounded by the Heart Butte Dam (completed 1949), built primarily for flood risk reduction on the HEART RIVER; earth-type dam, 142 ft tall and 1,850 ft long.
- Surface area
- 10,953 ac
- Normal storage
- 75,785 ac-ft
- Max storage
- 451,200 ac-ft
- Drainage area
- 1,714.46 sq mi
- Hazard class
- High
- Owner
- BUREAU OF RECLAMATION
All listed purposes: Flood Risk Reduction;Irrigation.
Source: USACE National Inventory of Dams, NID ID ND00149 · Operator website
EPA Impairment Status
Lake Tschida 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 ND-10130202-001-L_00 · Official waterbody report
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: 2025-09-18
Monitoring stations: 1