Locke Lake
Wright County, MinnesotaEutrophic
Locke Lake earns a C — middle-of-the-pack water quality, with one or two parameters dragging the average down from a stronger grade. clarity and phosphorus rate similarly, so there is no obvious single lever to pull on watershed management.
A TSI in the eutrophic range signals a lake doing what nutrient-loaded waters do — supporting an active algal community at the cost of clear water. A maximum depth of 49 ft puts Locke Lake in the middle of Minnesota's depth distribution. The lake's 140 acres and 2.6 miles of shoreline put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Within Wright County's 64 graded lakes, Locke Lake ranks 33 — below the local median, though not at the bottom.
Zebra mussels have been documented at Locke Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. Walleye are documented at Locke Lake, one of 15 fish species on record for the lake. Public access is available — the lake is on the Minnesota PCA public-access list. Ice-out has been logged at Locke Lake more than two dozen times, putting the median around Apr 8 — a useful baseline for tracking climate trends. 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, Minnesota DNR LakeFinder, last sampled 2024-09-15. Grade methodology: LakeGrade methodology.
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Swimming Safety
Generally safe for swimming, moderate water quality
Water Quality Grade: C, Fair
Murky, only visible to about 4.3 ft. Phosphorus level: 32 µg/L. Trophic State Index: 55.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.3 ft | D |
| Phosphorus | 32 µg/L | C |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 55 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 49 ft |
| Average Depth | 18.1 ft |
| Surface Area | 139.97 acres |
| Shoreline Length | 2.6 mi |
| Littoral Zone | 48% |
| Public Access | Yes |
Fish Species
Click a species to see all Minnesota and Wisconsin lakes where it is found.
→ Best fishing times for Locke Lake (14-day solunar calendar)
→ Is it safe to eat fish from Locke Lake? (mercury & PFAS guide)
→ Locke 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.
Water Quality Trend: ↓ Declining
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.055 m/yr | 5 |
| Phosphorus | ↓ Declining | +6.9 µg/L/yr | 5 |
Ice Season
Historical ice data from Minnesota DNR (48 observations).
Estimated open water season: 244 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2024-03-07 (2024) | 2018-05-01 (2018) |
| Ice-In | 2014-11-15 (2014) | 2024-01-11 (2024) |
Most recent ice-out: 2024-03-07
Location
County Ranking
Ranked #33 of 64 lakes in Wright County
Cleaner Lakes Within 30 Miles
Locke Lake holds Grade C. 4 nearby lakes hold higher grades.
- ASugar LakeWright County · mi · Two grade letters higher (C → A)
- AEmber LakeWright County · mi · Two grade letters higher (C → A)
- AIda LakeWright County · mi · Two grade letters higher (C → A)
- CIndian LakeWright County · mi · Higher overall water quality score
Nearby Lakes in Wright County
More Minnesota Lake Rankings
State Parks Near Locke Lake
Other Grade C Lakes in Minnesota
Eutrophic Lakes in Minnesota
DNR Fisheries Survey Summary
14 surveys on file from MN DNR Fisheries. Most recent: 2025-10-08 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| BKS | 104.25 | — |
| Black Bullhead | 41.51 | 0.43 lb |
| Bluegill | 20.04 | 0.23 lb |
| Walleye | 16.11 | 1.36 lb |
| Smallmouth Bass | 12.22 | 1.33 lb |
| Largemouth Bass | 11.14 | 1.94 lb |
CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.
Length Distributions
Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.
BKS
Black Bullhead
Bluegill
Walleye
From the 2025-10-08 survey
Locke Lake is a 156-acre general development lake located one mile southeast of Hasty in northern Wright County. The watershed is large (32,365 acres) and the primary land uses are cultivated crops (43%), forest (16%), and hay/pasture (11%). A downstream barrier on Silver Creek isolates Locke Lake from the Mississippi…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Locke Lake. 3 reports on file.
- —Fisheries Lake Survey — LockeFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — LockeFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — LockePublic Water Access Sites · MN DNR LakeFinder
EPA Impairment Status
Locke Lake 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 MN86-0168-00 · 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
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate
Most recent sample: 2024-09-15
Monitoring stations: 1