Mud Lake
Martin County, Minnesota182 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Mud Lake. Here is what has been measured.
- Hypereutrophic
- 19 ft max depth
- Public access
- Limited data
Mud Lake in Martin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 1.6 ft visibility. Phosphorus: 125.5 µg/L. Chlorophyll-a (algae): 53.4 µg/L. Maximum depth: 19 ft. Surface area: 182.09 acres.
Minnesota DNR's Standard Survey on August 22, 2022 caught 2.50 walleye per gill net at Mud Lake. DNR survey details →
Mud Lake is a 182-acre highly nutrient-loaded hypereutrophic lake in Martin County, Minnesota with a maximum depth of 19 feet (11-foot average). Overall water quality is improving over recent sampling years. The lake supports 17 documented fish species including bigmouth buffalo, black bullhead, and black crappie. Public access is available. Compared to the 11 other monitored lakes in Martin County, Mud Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-30. Methodology: how these readings are compared.
Mud Lake covers about 180 acres in Martin County. The median ice-out date is March 25, which is when the open-water season begins. For a place on the water, look through cabin and lake-house rentals near Mud Lake on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Mud Lake is good for
From access and monitoring records, not editorial picks.
- Fishing17 species recorded
- Ice seasonIce-out around Mar 25
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 Mud 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 Mud Lake
These are the measurements Minnesota PCA publishes for Mud Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 1.6 ft of visibility. Phosphorus 125.5 µg/L. Chlorophyll-a 53.4 µg/L. TSI 71.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 1.6ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 126µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 53.4µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 71 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Mud Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Mud Lake typically sits around 67°F at the surface in August. Summer average is about 75°F. Usually warmest in Jun (about 80°F) and coldest in Aug (about 67°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (67°F) to its warmest (80°F).
Typical surface water temperature by month, from 9 field readings (2025–2025) via the EPA Water Quality Portal.
Minnesota DNR's Standard Survey on August 22, 2022 caught 2.50 walleye per gill net at Mud Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Mud Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
12 surveys on file from MN DNR Fisheries. Most recent: 2022-08-22 (Standard Survey).
12 surveys on file · most recent 2022-08-22 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Black Bullhead | 44.04 | 7–11 in 2022-08-22 | 0.36 lb |
| Common Carp | 21.39 | 4–28 in 2022-08-22 | 2.88 lb |
| Black Crappie | 15.03 | 7–12 in 2022-08-22 | 0.3 lb |
| Freshwater Drum | 12.24 | 7–15 in 2022-08-22 | 0.43 lb |
| Yellow Perch | 9.35 | 8–9 in 2022-08-22 | 0.17 lb |
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.
Black Bullhead
Common Carp
Black Crappie
Freshwater Drum
From the 2022-08-22 survey
Amber Lake is a 180 acre lake with a max depth of 19 feet and 108 acres of littoral zone (15 feet or less). Amber Lake is part of the "Fairmont Chain of Lakes" and is within the city limits of Fairmont. The Fairmont Chain of Lakes (from headwaters to mouth) is comprised of Amber Lake, Hall Lake, Budd Lake, Sisseton…
Lake Details
Max depth
19 ft
Average depth
11 ft
Surface area
182 acres
Shoreline
2.2 mi
Littoral zone
59%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
32 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,155 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Mud Lake
Compare lakeside cabins, hotels, and vacation rentals near Mud Lake in Martin 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 readings cover nutrients and algae, not lodging. Cabins and rentals around Mud Lake are listed below.
Top-rated places to stay near Mud Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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 →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Mud Lake
Water Quality Trend: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving6 years
Phosphorus
Improving-9.13 µg/L/yr6 years
Chlorophyll-a
Stable+0.29 µg/L/yr6 years
Ice season
Typical ice-out
Mar 25
Earliest Feb 29, 2024 · Latest Apr 29, 2018
Typical ice-in
Dec 1
Earliest Nov 13, 2018 · Latest Dec 14, 2017
Most recent ice-out
Mar 10
2026
27 observations · Minnesota PCA ice records
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Mud Lake under Clean Water Act (NPDES) discharge permits.
- Fairmont Puc-LincolnFairmont · 0.7 mi away · NPDES MN0045691
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.
Nearby Lakes in Martin County
Frequently asked questions about Mud Lake
Where is Mud Lake?
- Mud Lake is a lake in Martin County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Mud Lake?
- Mud Lake in Martin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 1.6 ft visibility. Phosphorus: 125.5 µg/L. Chlorophyll-a (algae): 53.4 µg/L. Maximum depth: 19 ft. Surface area: 182.09 acres.
Is Mud 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 Mud Lake?
- Mud Lake typically sits around 67°F at the surface in August, from 9 EPA Water Quality Portal field readings (2025–2025). That is a typical value for the month, not a live reading.
How deep is Mud Lake?
- Mud Lake has a maximum depth of 19 feet and an average depth of 11 feet. The lake covers 182.09 acres.
What fish are in Mud Lake?
- Fish species found in Mud Lake include bigmouth buffalo, black bullhead, black crappie, bluegill, channel catfish, common carp, freshwater drum, green sunfish, largemouth bass, orangespotted sunfish, quillback, walleye, white crappie, white sucker, yellow bass, yellow bullhead, yellow perch. Mud Lake is located in Martin County, Minnesota.
What did the DNR fisheries survey find at Mud Lake?
- Minnesota DNR's Standard Survey on August 22, 2022 caught 2.50 walleye per gill net at Mud Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Mud Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
When does Mud Lake thaw?
- Mud Lake typically has ice-out around Mar 25. Ice typically forms around Dec 1. The open water season is approximately 251 days.
Can I fish at Mud Lake?
- Public access to Mud Lake is listed as yes on the lake record. 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 Mud Lake across LakeQuality
Fish species and the cleanest lakes across Minnesota
Fish species and best lakes in Martin County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Minnesota's cleanest lakes, ranked on agency measurements
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Other Lakes in Minnesota
Hypereutrophic Lakes in Minnesota
Where this data comes from
18 measurements from 1 monitoring station, 2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA18 samples · 2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H 3 ~ Chlorophyll a-b-c Determination by fluorometer
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate