Swan Lake
Columbia County, WisconsinLimited DataEutrophic
Swan Lake pulls a D on the LakeGrade rubric — phosphorus loading and limited clarity hold it below the Wisconsin average.
Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. The lake's 82 ft maximum depth is in the upper tier for Wisconsin — deep enough for cold-water fish to find refuge in summer. Swan Lake covers 407 acres alongside partial shoreline records — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Swan Lake ranks 3 of 10 in Columbia County — solidly in the upper half of the local distribution.
Eurasian watermilfoil has been documented at Swan Lake, requiring shoreline management to keep dense mats from crowding native vegetation. The fishery includes walleye among the lake's 5 documented species — a notable draw for Wisconsin anglers. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-09-28. Grade methodology: LakeGrade methodology.
Track Swan Lake
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D, Poor
Murky, only visible to about 4.8 ft. Trophic State Index: 55.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.8 ft | D |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 55 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 82 ft |
| Surface Area | 407 acres |
Fish Species
Click a species to see all Wisconsin and Minnesota lakes where it is found.
→ Best fishing times for Swan Lake (14-day solunar calendar)
→ Is it safe to eat fish from Swan Lake? (mercury & PFAS guide)
→ Swan Lake fishing regulations (limits, seasons, special rules)
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
Location
County Ranking
Ranked #3 of 10 lakes in Columbia County
Cleaner Lakes Within 30 Miles
Swan Lake holds Grade D. 3 nearby lakes hold higher grades.
Nearby Lakes in Columbia County
More Wisconsin Lake Rankings
State Parks Near Swan Lake
Other Grade D Lakes in Wisconsin
Eutrophic Lakes in Wisconsin
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 1988. 12 stations on file (most recent sample 2025).
Fish Species (DNR-rated)
EPA Impairment Status
Swan Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit WI10000772 · 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: 2025-09-28
Monitoring stations: 1