Cochran Lake
Price County, WisconsinOligotrophic
Cochran Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Price County. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.
Trophically, Cochran Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. A maximum depth of 20 ft puts Cochran Lake in the middle of Wisconsin's depth distribution. At 111 acres, Cochran Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Among the 26 graded lakes in Price County, Cochran Lake ranks 2 — in the top quartile locally.
Cochran Lake has no invasive species recorded in Wisconsin state databases as of 2025, though prevention practices still apply at all access points. Bass fishing is part of the appeal: the species list runs to 2, anchored by largemouth and/or smallmouth bass. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-10-29. Grade methodology: LakeGrade methodology.
Swimming Safety
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A, Excellent
Crystal clear, you can see 37.7 ft down. Phosphorus level: 14.2 µg/L. Trophic State Index: 34.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 37.7 ft | A |
| Phosphorus | 14.2 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 34 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 20 ft |
| Surface Area | 111 acres |
Fish Species
Click a species to see all Wisconsin and Minnesota lakes where it is found.
→ Best fishing times for Cochran Lake (14-day solunar calendar)
→ Is it safe to eat fish from Cochran Lake? (mercury & PFAS guide)
→ Cochran Lake fishing regulations (limits, seasons, special rules)
Water Quality Trend: ↓ Declining
Based on 7 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | +0.17 m/yr | 7 |
| Phosphorus | ↓ Declining | +0.63 µg/L/yr | 6 |
Location
County Ranking
Ranked #2 of 26 lakes in Price County
Nearby Lakes in Price County
More Wisconsin Lake Rankings
Other Grade A Lakes in Wisconsin
Waukesha County · Clarity: 14.6 ft
Waukesha County · Clarity: 13.8 ft
Walworth County · Clarity: 19 ft
Washington County · Clarity: 12 ft
Kenosha County · Clarity: 10.1 ft
Washington County · Clarity: 12.5 ft
Oligotrophic Lakes in Wisconsin
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 1998. 2 stations on file (most recent sample 2025).
Fish Species (DNR-rated)
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Fish and recreation data from Wisconsin DNR Lakes
Most recent sample: 2025-10-29
Monitoring stations: 1