Hay Lake
Cass County, Minnesota364 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Hay Lake. Here is what has been measured.
- Mesotrophic
- 56 ft max depth
- Public access
- Limited data
Hay Lake in Cass County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 13.2 ft visibility. Phosphorus: 16.5 µg/L. Chlorophyll-a (algae): 2.4 µg/L. Maximum depth: 56 ft. Surface area: 363.7 acres.
Minnesota DNR's Standard Survey on June 10, 2024 caught 0.50 walleye per gill net at Hay Lake. DNR survey details →
Hay Lake is a 364-acre mesotrophic lake in Cass County, Minnesota with a maximum depth of 56 feet. The lake supports 14 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 103 other monitored lakes in Cass County, Hay Lake ranks #67 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-09-06. Methodology: how these readings are compared.
What Hay Lake is good for
From access and monitoring records, not editorial picks.
- Clear water13.2 ft of visibility
- Boat launch1 documented ramp
- Fishing14 species recorded
- Deep water56 ft surveyed max depth
Swimming conditions
Readings onlyLimited data
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Hay Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Hay Lake
These are the measurements Minnesota PCA publishes for Hay Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 13.2 ft. Phosphorus 16.5 µg/L. Chlorophyll-a 2.4 µg/L. TSI 41.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 13.2ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 16.5µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 2.4µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 41 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Hay Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Hay Lake typically sits around 59°F at the surface in September. Summer average is about 59°F. Usually warmest in Aug (about 60°F) and coldest in May (about 49°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (49°F) to its warmest (60°F).
Typical surface water temperature by month, from 127 field readings (2011–2024) via the EPA Water Quality Portal. See the full Hay Lake water temperature breakdown →
Minnesota DNR's Standard Survey on June 10, 2024 caught 0.50 walleye per gill net at Hay Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Hay Lake’s water-quality measurements separately. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
14 surveys on file from MN DNR Fisheries. Most recent: 2024-08-01 (Targeted Survey).
14 surveys on file · most recent 2024-08-01 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 22.16 | 3–10 in 2024-06-10 | 0.19 lb |
| Bluntnose Minnow | 19.80 | ||
| Golden Shiner | 14.65 | ||
| Spottail Shiner | 6.89 |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
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
From the 2024-08-01 survey
Temperature and dissolved oxygen profiles were collected in the deepest basins in Hay Lake on August 1, 2024 , to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Cisco, also known as Tullibee, the most sensitive coldwater species present in this lake. Cisco require a…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Hay Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — HayFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Hay (1527)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — HayFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — HayPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
56 ft
Surface area
364 acres
Shoreline
5.2 mi
Littoral zone
49%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
5 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,329 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Hay LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Hay Lake
Compare lakeside cabins, hotels, and vacation rentals near Hay 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 Hay Lake
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Follow Hay Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Hay Lake
Nearby Lakes in Cass County
Frequently asked questions about Hay Lake
Where is Hay Lake?
- Hay Lake is a lake in Cass County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Hay Lake?
- Hay Lake in Cass County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 13.2 ft visibility. Phosphorus: 16.5 µg/L. Chlorophyll-a (algae): 2.4 µg/L. Maximum depth: 56 ft. Surface area: 363.7 acres.
Is Hay Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Hay Lake?
- Hay Lake typically sits around 59°F at the surface in September, from 127 EPA Water Quality Portal field readings (2011–2024). That is a typical value for the month, not a live reading.
How deep is Hay Lake?
- Hay Lake has a maximum depth of 56 feet. The lake covers 363.7 acres.
What fish are in Hay Lake?
- Fish species found in Hay Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, tullibee (cisco), walleye, yellow bullhead, yellow perch. Hay Lake is located in Cass County, Minnesota.
What did the DNR fisheries survey find at Hay Lake?
- Minnesota DNR's Standard Survey on June 10, 2024 caught 0.50 walleye per gill net at Hay Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Hay Lake’s water-quality measurements separately. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Hay Lake?
- Hay Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Hay Lake. Public access is listed as yes.
Can I fish at Hay Lake?
- Hay Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Hay Lake across LakeQuality
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Fish species and best lakes in Cass County
Species activity outlook by water temperature and season
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Where this data comes from
20 measurements from 1 monitoring station, 2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA20 samples · 2023
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory