Fish Lake
Fish Lake in Kanabec County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 2 ft visibility. Maximum depth: 8 ft. Surface area: 506.41 acres.
- Clarity
- 2 ft
- Typical in August
- 74°F
- Max depth
- 8 ft
- Area
- 506 acres
- Trend
- ↓ Declining
- Public access
- Yes
- Ice-out
- Apr 19
- Open water
- 217 days
Next lake in Kanabec County
Why Fish Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Fish Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Fish Lake is a 506-acre lake in Kanabec County, Minnesota with a maximum depth of 8 feet. Overall water quality is declining over recent sampling years. The lake supports 21 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 2 public boat landings.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-29. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Fish Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Very murky, less than 2 ft of visibility. Trophic State Index: 67.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 67 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Fish Lake
Compare lakeside cabins, hotels, and vacation rentals near Fish Lake in Kanabec County, Minnesota — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Fish Lake
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Water Temperature
Fish Lake typically sits around 74°F at the surface in August. Summer average is about 74°F. Usually warmest in Jul (about 77°F) and coldest in Oct (about 46°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 51 field readings (2018–2025) via the EPA Water Quality Portal. See the full Fish Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Fish Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was high (216,770 cells/mL) on July 11, 2026.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 8 ft |
| Surface Area | 506 acres |
| Shoreline Length | 10 mi |
| Littoral Zone | 99% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Fish Lake (South)Public
- Fish Lake (North)Public
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Fish Lake
DNR Fisheries Survey Summary
14 surveys on file from MN DNR Fisheries. Most recent: 2025-10-13 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Black Crappie | 32.34 | 0.33 lb |
| Largemouth Bass | 26.20 | 2.49 lb |
| Spottail Shiner | 18.69 | — |
| Bluegill | 14.83 | 0.3 lb |
| Walleye | 14.08 | 2.1 lb |
| CNM | 12.01 | — |
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.
Black Crappie
Largemouth Bass
Bluegill
Walleye
From the 2025-10-13 survey
Fish Lake is a 506-acre shallow impoundment on the Ann River in southern Kanabec County located four miles south of Mora and is within the Snake River Watershed. The lake has a maximum depth of 8 feet and an average depth of 5 feet. The lake is 100% littoral (15 feet or less, 506 acres). Water clarity is poor with…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Fish Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — FishFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Fish (0284)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — FishFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — FishPublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: ↓ Declining
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.113 m/yr | 6 |
Ice Season
Historical ice data from Minnesota DNR (24 observations).
Estimated open water season: 217 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2024-03-06 (2024) | 2018-04-30 (2018) |
| Ice-In | 2006-11-03 (2006) | 2025-12-02 (2025) |
Most recent ice-out: 2025-04-02
Reservoir Info (USACE NID)
Fish Lake is a man-made reservoir impounded by the Fish Lake (completed 1930), built primarily for other on the Ann River; gravity-type dam, 13 ft tall and 1,200 ft long.
- Surface area
- 440 ac
- Normal storage
- 2,442 ac-ft
- Max storage
- 3,663 ac-ft
- Drainage area
- 87 sq mi
- Hazard class
- Low
- Owner
- MNDNR-Fisheries and Wildlife
Source: USACE National Inventory of Dams, NID ID MN00572 · Operator website
EPA Impairment Status
Fish 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 MN33-0036-00 · Official waterbody report
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Fish Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Ogilvie WwtpOgilvie · 3.8 mi away · NPDES MN0021997Recent violation
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Graded lakes near Fish Lake
Fish Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Kanabec County
Frequently asked questions about Fish Lake
What is the water quality grade for Fish Lake?
- Fish Lake in Kanabec County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 2 ft visibility. Maximum depth: 8 ft. Surface area: 506.41 acres.
Is Fish Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Fish Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
What is the water temperature of Fish Lake?
- Fish Lake typically sits around 74°F at the surface in August, from 51 EPA Water Quality Portal field readings (2018–2025). That is a typical value for the month, not a live reading.
How deep is Fish Lake?
- Fish Lake has a maximum depth of 8 feet. The lake covers 506.41 acres.
What fish are in Fish Lake?
- Fish species found in Fish Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, channel catfish, common carp, freshwater drum, golden redhorse, greater redhorse, largemouth bass, northern pike, pumpkinseed, shorthead redhorse, smallmouth bass, walleye, white bass, white crappie, white sucker, yellow bullhead, yellow perch. Fish Lake is located in Kanabec County, Minnesota.
When does Fish Lake thaw?
- Fish Lake typically has ice-out around Apr 19. Ice typically forms around Nov 22. The open water season is approximately 217 days.
Does Fish Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Fish Lake (clouds, ice, or an off-season gap). The most recent reading was high (216,770 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Fish Lake?
- Fish Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Fish Lake (South), Fish Lake (North). Public access is listed as yes.
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Where this data comes from
78 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA78 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate