Widow Lake
Widow Lake in Cass County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 18.5 ft visibility. Maximum depth: 46 ft. Surface area: 197.5 acres.
- Clarity
- 18.5 ft
- Typical in August
- 74°F
- Max depth
- 46 ft
- Area
- 198 acres
- Trend
- ↑ Improving
- Public access
- Yes
Next lake in Cass County
Why Widow 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 Widow 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.
Widow Lake is a 198-acre lake in Cass County, Minnesota with a maximum depth of 46 feet. Overall water quality is improving over recent sampling years. The lake supports 12 documented fish species including black crappie, bluegill, and bowfin (dogfish). Public access is available with 2 public boat landings.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-08-31. 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 Widow Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Crystal clear, you can see 18.5 ft down. Trophic State Index: 35.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 18.5 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 35 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Widow Lake
Compare lakeside cabins, hotels, and vacation rentals near Widow Lake in Cass 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 Widow Lake
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Water Temperature
Widow Lake typically sits around 74°F at the surface in August. Summer average is about 74°F. Usually warmest in Jul (about 78°F) and coldest in Jun (about 69°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 8 field readings (2011–2025) via the EPA Water Quality Portal. See the full Widow Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 46 ft |
| Surface Area | 198 acres |
| Shoreline Length | 3 mi |
| Littoral Zone | 37% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Sand LakePublic
- Widow LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Widow Lake
DNR Fisheries Survey Summary
9 surveys on file from MN DNR Fisheries. Most recent: 2022-06-21 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Bluegill | 25.97 | 0.16 lb |
| BCS | 22.33 | — |
| Largemouth Bass | 6.72 | 0.59 lb |
| Black Crappie | 5.13 | 0.4 lb |
| Yellow Bass | 4.61 | 0.56 lb |
| Bluntnose Minnow | 3.40 | — |
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.
Bluegill
Largemouth Bass
Black Crappie
Yellow Bass
From the 2022-06-21 survey
A targeted survey of nearshore fish species in Widow Lake was conducted on June 21-23, 2022 by Index of Biological Integrity (IBI) Program Staff. Sampling sites were evenly spaced around the lake and each was sampled by backpack electrofishing and seining with a 50-foot seine, where possible. Backpack electrofishing…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Widow Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — WidowFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Widow (1594)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — WidowFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — WidowPublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: ↑ Improving
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.223 m/yr | 6 |
EPA Impairment Status
Widow 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 MN11-0274-00 · Official waterbody report · Matched by proximity (2.55 km)
Graded lakes near Widow Lake
Widow Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Cass County
Frequently asked questions about Widow Lake
What is the water quality grade for Widow Lake?
- Widow Lake in Cass County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 18.5 ft visibility. Maximum depth: 46 ft. Surface area: 197.5 acres.
Is Widow Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Widow 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 Widow Lake?
- Widow Lake typically sits around 74°F at the surface in August, from 8 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Widow Lake?
- Widow Lake has a maximum depth of 46 feet. The lake covers 197.5 acres.
What fish are in Widow Lake?
- Fish species found in Widow Lake include black crappie, bluegill, bowfin (dogfish), brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, walleye, yellow bullhead, yellow perch. Widow Lake is located in Cass County, Minnesota.
Are there boat ramps on Widow Lake?
- Widow Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Sand Lake, Widow Lake. Public access is listed as yes.
Explore Widow Lake across LakeGrade
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Where this data comes from
21 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
MNPCA21 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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory