Crane Lake
St. Louis County, MinnesotaLimited DataEutrophic
Crane Lake pulls a D on the LakeGrade rubric — phosphorus loading and limited clarity hold it below the Minnesota average. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.
At a TSI of 51, Crane Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. The lake's 80 ft maximum depth is in the upper tier for Minnesota — deep enough for cold-water fish to find refuge in summer. At 2,921 acres, Crane Lake is one of the larger lakes in St. Louis County, with 34.0 miles of shoreline supporting multiple distinct use patterns. Within the 187 graded lakes of St. Louis County, Crane Lake sits at rank 163, near the bottom of the county list.
An invasive species record — spiny waterflea — has been logged at Crane Lake; Minnesota PCA maintains the official infested-waters list. Muskie are on the species list at Crane Lake, alongside the lake's 12 other documented fish. A documented public access point at Crane Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The lake has a partial ice record — 6 observed ice-outs, centered near Apr 27. 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 2024-09-27. Grade methodology: LakeGrade methodology.
Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D, Poor
Murky, only visible to about 6 ft. Trophic State Index: 51.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 6 ft | D |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 51 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 80 ft |
| Surface Area | 2.9K acres |
| Shoreline Length | 34 mi |
| Littoral Zone | 21% |
| Public Access | Yes |
Fish Species
Click a species to see all Minnesota and Wisconsin lakes where it is found.
→ Best fishing times for Crane Lake (14-day solunar calendar)
→ Is it safe to eat fish from Crane Lake? (mercury & PFAS guide)
→ Crane Lake fishing regulations (limits, seasons, special rules)
Invasive Species
Water Quality Trend: ↓ Declining
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.219 m/yr | 5 |
Ice Season
Historical ice data from Minnesota DNR (6 observations).
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2012-03-27 (2012) | 2014-05-14 (2014) |
Most recent ice-out: 2019-04-24
Location
County Ranking
Ranked #163 of 187 lakes in St. Louis County
Cleaner Lakes Within 30 Miles
Crane Lake holds Grade D. 2 nearby lakes hold higher grades.
- AMukooda LakeSt. Louis County · 3.5 mi · Two grade letters higher (D → A)
- ALittle Trout LakeSt. Louis County · 8.2 mi · Two grade letters higher (D → A)
Nearby Lakes in St. Louis County
More Minnesota Lake Rankings
Other Grade D Lakes in Minnesota
Eutrophic Lakes in Minnesota
DNR Fisheries Survey Summary
17 surveys on file from MN DNR Fisheries. Most recent: 2025-08-20 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Smallmouth Bass | 13.48 | 0.98 lb |
| Walleye | 7.82 | 0.8 lb |
| Tullibee (Cisco) | 6.00 | 0.6 lb |
| Yellow Perch | 5.50 | 0.14 lb |
| Northern Pike | 2.02 | 3.04 lb |
| White Sucker | 1.99 | 2.16 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.
Smallmouth Bass
Walleye
Tullibee (Cisco)
Yellow Perch
From the 2025-08-20 survey
Temperature and dissolved oxygen (DO) measurements were collected from the deepest basin in Crane Lake on August 20th, 2025, to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Lake Whitefish, the most sensitive coldwater species present in this lake (Cisco, also…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Crane Lake. 3 reports on file.
- —Fisheries Lake Survey — CraneFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Crane (1910)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — CranePublic Water Access Sites · MN DNR LakeFinder
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate
Most recent sample: 2024-09-27
Monitoring stations: 1