Big Lake
Big Lake in Stearns County, Minnesota has a water quality grade of C (Fair). Water clarity: 6.9 ft visibility. Phosphorus: 26.5 µg/L. Chlorophyll-a (algae): 10.7 µg/L. Maximum depth: 42 ft. Surface area: 457.67 acres.
- Clarity
- 6.9 ft
- Typical in August
- 75°F
- Max depth
- 42 ft
- Area
- 458 acres
- Type
- Eutrophic
- Trend
- ↓ Declining
- Public access
- Yes
- Ice-out
- Apr 11
- Open water
- 229 days
Next lake in Stearns County
Big Lake is a 458-acre productive, nutrient-rich eutrophic lake in Stearns County, Minnesota with a maximum depth of 42 feet (15-foot average). Water quality is graded C based on 2 sampling years through 2025. Overall water quality is declining over recent sampling years. 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, Big Lake ranks #6 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-30. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyModerate
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.
Generally safe for swimming, moderate water quality
Water Quality Grade: C (Fair)
Moderate clarity, visible to about 6.9 ft. Phosphorus level: 26.5 µg/L. Chlorophyll-a: 10.7 µg/L. Trophic State Index: 52.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 6.9 ft | Not graded |
| Phosphorus | 26.5 µg/L | Fair |
| Chlorophyll-a (Algae) | 10.7 µg/L | Fair |
| Trophic State Index (TSI) | 52 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Big Lake
Compare lakeside cabins, hotels, and vacation rentals near Big 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.
Top-rated places to stay near Big Lake
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Water Temperature
Big Lake typically sits around 75°F at the surface in August. Summer average is about 75°F. Usually warmest in Jul (about 78°F) and coldest in May (about 60°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 60 field readings (2010–2021) via the EPA Water Quality Portal. See the full Big Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 42 ft |
| Average Depth | 14.6 ft |
| Surface Area | 458 acres |
| Shoreline Length | 7.5 mi |
| Littoral Zone | 50% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Big LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Big Lake
DNR Fisheries Survey Summary
8 surveys on file from MN DNR Fisheries. Most recent: 2017-08-07 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Bluegill | 35.90 | 0.14 lb |
| Largemouth Bass | 25.51 | 0.71 lb |
| BKF | 15.77 | — |
| PGS | 10.77 | — |
| Yellow Bass | 9.74 | 0.72 lb |
| Bluntnose Minnow | 8.01 | — |
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.
Bluegill
Largemouth Bass
Yellow Bass
From the 2017-08-07 survey
Big Lake is a 458 acre lake located three miles southwest of the City of Richmond. It has a maximum depth of 42 feet with an average depth of 15 feet. Big Lake has good water quality and excellent water clarity with a 10 year average summer Secchi reading of 10 feet. The Big Lake watershed is 20,371 acres with land…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Big Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — BigFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Big (1997)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — BigFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — BigPublic 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 | -0.224 m/yr | 6 |
| Phosphorus | ↓ Declining | +0.7 µg/L/yr | 6 |
| Chlorophyll-a | ↓ Declining | +1.73 µg/L/yr | 6 |
Ice Season
Historical ice data from Minnesota DNR (15 observations).
Estimated open water season: 229 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2017-03-01 (2017) | 2018-05-01 (2018) |
| Ice-In | 2014-11-14 (2014) | 2004-12-14 (2004) |
Most recent ice-out: 2019-04-20
EPA Impairment Status
Big Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit MN73-0159-00 · Official waterbody report
County Ranking
Ranked #6 of 32 lakes in Stearns County
Nearby Lakes in Stearns County
Frequently asked questions about Big Lake
What is the water quality grade for Big Lake?
- Big Lake in Stearns County, Minnesota has a water quality grade of C (Fair). Water clarity: 6.9 ft visibility. Phosphorus: 26.5 µg/L. Chlorophyll-a (algae): 10.7 µg/L. Maximum depth: 42 ft. Surface area: 457.67 acres.
Is Big Lake safe to swim in?
- Generally safe for swimming, moderate water quality. Big Lake has a water quality grade of C (Fair). Algae concentration (chlorophyll-a) is 10.7 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Big Lake?
- Big Lake typically sits around 75°F at the surface in August, from 60 EPA Water Quality Portal field readings (2010–2021). That is a typical value for the month, not a live reading.
How deep is Big Lake?
- Big Lake has a maximum depth of 42 feet and an average depth of 14.6 feet. The lake covers 457.67 acres.
What fish are in Big Lake?
- Fish species found in Big Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, channel catfish, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, smallmouth bass, walleye, white sucker, yellow bullhead, yellow perch. Big Lake is located in Stearns County, Minnesota.
When does Big Lake thaw?
- Big Lake typically has ice-out around Apr 11. Ice typically forms around Nov 26. The open water season is approximately 229 days.
Are there boat ramps on Big Lake?
- Big Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Big Lake. Public access is listed as yes.
Explore Big Lake across LakeGrade
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High nutrients, frequent algae, reduced clarity
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Where this data comes from
167 measurements from 2 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA167 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (2)
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