Mud Lake
Mud Lake in Stearns County, Minnesota has a water quality grade of F (Algae-prone). Water clarity: 3 ft visibility. Phosphorus: 166 µg/L. Chlorophyll-a (algae): 59.5 µg/L. Maximum depth: 20 ft. Surface area: 160.64 acres.
- Clarity
- 3 ft
- Typical in August
- 70°F
- Max depth
- 20 ft
- Area
- 161 acres
- Type
- Eutrophic
- Public access
- Yes
- Ice-out
- Apr 15
Grade F measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Mud Lake →
Next lake in Stearns County
Mud Lake is a 161-acre productive, nutrient-rich eutrophic lake in Stearns County, Minnesota with a maximum depth of 20 feet (9-foot average). Water quality is graded F based on 2 sampling years through 2023. The lake supports 16 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 31 other monitored lakes in Stearns County, Mud Lake ranks #22 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-09-14. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Algae and nutrients are often high — check current advisories before swimming. Skip the water if you see scum or a paint-like bloom
Water Quality Grade: F (Algae-prone)
Very murky, less than 3 ft of visibility. Phosphorus level: 166 µg/L. Chlorophyll-a: 59.5 µg/L. Trophic State Index: 70.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3 ft | Not graded |
| Phosphorus | 166 µg/L | Poor |
| Chlorophyll-a (Algae) | 59.5 µg/L | Poor |
| Trophic State Index (TSI) | 70 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Mud Lake
Compare lakeside cabins, hotels, and vacation rentals near Mud Lake in Stearns 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. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Mud Lake are listed below.
Top-rated places to stay near Mud Lake
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Minnesota’s top lakes →
Water Temperature
Mud Lake typically sits around 70°F at the surface in August. Summer average is about 69°F. Usually warmest in Aug (about 70°F) and coldest in May (about 59°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 51 field readings (2023–2023) via the EPA Water Quality Portal. See the full Mud Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 20 ft |
| Average Depth | 8.6 ft |
| Surface Area | 161 acres |
| Shoreline Length | 1.9 mi |
| Littoral Zone | 79% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Mud LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Mud Lake
DNR Fisheries Survey Summary
10 surveys on file from MN DNR Fisheries. Most recent: 2024-06-10 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Black Bullhead | 52.28 | 0.49 lb |
| Largemouth Bass | 19.73 | 1.02 lb |
| Bluegill | 19.35 | 0.18 lb |
| Yellow Perch | 13.99 | 0.14 lb |
| Black Crappie | 12.61 | 0.27 lb |
| Green Sunfish | 10.43 | 0.21 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.
Black Bullhead
Largemouth Bass
Bluegill
Yellow Perch
From the 2024-06-10 survey
Vails Lake (aka Mud Lake) is a 151-acre lake located just north of Eden Valley in southern Stearns County. It has a maximum depth of 20 feet. It is the first in a series of lakes which outlet northward to the Sauk River chain of lakes. The watershed is large and dominated by agriculture, pasture, and development. A…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Mud Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — VailsFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — VailsFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — VailsPublic Water Access Sites · MN DNR LakeFinder
Ice Season
Historical ice data from Minnesota DNR (5 observations).
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2004-04-02 (2004) | 2023-04-16 (2023) |
| Ice-In | 2003-12-10 (2003) | 2001-12-22 (2001) |
Most recent ice-out: 2023-04-16
EPA Impairment Status
Mud 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 MN73-0151-00 · Official waterbody report · Matched by proximity (0.18 km)
County Ranking
Ranked #22 of 32 lakes in Stearns County
Nearby Lakes With Higher Grades
Mud Lake holds Grade F. 2 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.
Nearby Lakes in Stearns County
Frequently asked questions about Mud Lake
What is the water quality grade for Mud Lake?
- Mud Lake in Stearns County, Minnesota has a water quality grade of F (Algae-prone). Water clarity: 3 ft visibility. Phosphorus: 166 µg/L. Chlorophyll-a (algae): 59.5 µg/L. Maximum depth: 20 ft. Surface area: 160.64 acres.
Is Mud Lake safe to swim in?
- Algae and nutrients are often high — check current advisories before swimming. Skip the water if you see scum or a paint-like bloom. Mud Lake has a water quality grade of F (Algae-prone). Algae concentration (chlorophyll-a) is 59.5 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Mud Lake?
- Mud Lake typically sits around 70°F at the surface in August, from 51 EPA Water Quality Portal field readings (2023–2023). That is a typical value for the month, not a live reading.
How deep is Mud Lake?
- Mud Lake has a maximum depth of 20 feet and an average depth of 8.6 feet. The lake covers 160.64 acres.
What fish are in Mud Lake?
- Fish species found in Mud Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, channel catfish, common carp, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, walleye, white sucker, yellow bullhead, yellow perch. Mud Lake is located in Stearns County, Minnesota.
When does Mud Lake thaw?
- Mud Lake typically has ice-out around Apr 15.
Are there boat ramps on Mud Lake?
- Mud Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Mud Lake. Public access is listed as yes.
Explore Mud Lake across LakeGrade
Fish species and top-graded lakes across Minnesota
Fish species and best lakes in Stearns County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its grade
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High nutrients, frequent algae, reduced clarity
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Where this data comes from
29 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
MNPCA29 samples · 2023
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H 2 ~ Chlorophyll a-b-c Determination by spectrophotometer
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
Ice data from Minnesota DNR Climate