Grand Lake
Grand Lake in Stearns County, Minnesota has a water quality grade of C (Fair). Water clarity: 8 ft visibility. Phosphorus: 27 µg/L. Chlorophyll-a (algae): 8.5 µg/L. Maximum depth: 34 ft. Surface area: 650.53 acres.
- Clarity
- 8 ft
- Typical in August
- 73°F
- Max depth
- 34 ft
- Area
- 651 acres
- Type
- Eutrophic
- Trend
- → Stable
- Public access
- Yes
- Ice-out
- Apr 19
- Open water
- 223 days
Next lake in Stearns County
Grand Lake is a 651-acre productive, nutrient-rich eutrophic lake in Stearns County, Minnesota with a maximum depth of 34 feet (19-foot average). Water quality is graded C based on 2 sampling years through 2025. 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 31 other monitored lakes in Stearns County, Grand Lake ranks #12 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-08-27. 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.
Generally safe for swimming, moderate water quality
Water Quality Grade: C (Fair)
Moderate clarity, visible to about 8 ft. Phosphorus level: 27 µg/L. Chlorophyll-a: 8.5 µg/L. Trophic State Index: 50.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 8 ft | Not graded |
| Phosphorus | 27 µg/L | Fair |
| Chlorophyll-a (Algae) | 8.5 µg/L | Fair |
| Trophic State Index (TSI) | 50 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Grand Lake
Compare lakeside cabins, hotels, and vacation rentals near Grand 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.
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Water Temperature
Grand Lake typically sits around 73°F at the surface in August. Summer average is about 71°F. Usually warmest in Jul (about 73°F) and coldest in May (about 62°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 113 field readings (2016–2025) via the EPA Water Quality Portal. See the full Grand Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 34 ft |
| Average Depth | 19 ft |
| Surface Area | 651 acres |
| Shoreline Length | 3.8 mi |
| Littoral Zone | 36% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Grand LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Grand Lake
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
DNR Fisheries Survey Summary
10 surveys on file from MN DNR Fisheries. Most recent: 2025-08-18 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| BKF | 91.20 | — |
| Bluntnose Minnow | 50.05 | — |
| BNS | 26.81 | — |
| MMS | 23.95 | — |
| Bluegill | 23.18 | 0.13 lb |
| Yellow Perch | 15.66 | 0.1 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.
Bluegill
Yellow Perch
From the 2025-08-18 survey
Grand Lake is a 655-acre, highly developed lake located approximately two miles south of Rockville in eastern Stearns County. The lake has moderate to good water quality with an average summer Secchi depth of 8.9 feet, reflecting improved water clarity since the last survey. It is classified as lake class 27. The…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Grand Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — GrandFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — GrandFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — GrandPublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: → Stable
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | -0.026 m/yr | 6 |
Ice Season
Historical ice data from Minnesota DNR (23 observations).
Estimated open water season: 223 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 1996-02-24 (1996) | 2014-04-27 (2014) |
| Ice-In | 1996-11-13 (1996) | 2001-12-21 (2001) |
Most recent ice-out: 2014-04-27
EPA Impairment Status
Grand 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 MN73-0055-00 · Official waterbody report
County Ranking
Ranked #12 of 32 lakes in Stearns County
Nearby Lakes in Stearns County
Frequently asked questions about Grand Lake
What is the water quality grade for Grand Lake?
- Grand Lake in Stearns County, Minnesota has a water quality grade of C (Fair). Water clarity: 8 ft visibility. Phosphorus: 27 µg/L. Chlorophyll-a (algae): 8.5 µg/L. Maximum depth: 34 ft. Surface area: 650.53 acres.
Is Grand Lake safe to swim in?
- Generally safe for swimming, moderate water quality. Grand Lake has a water quality grade of C (Fair). Algae concentration (chlorophyll-a) is 8.5 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Grand Lake?
- Grand Lake typically sits around 73°F at the surface in August, from 113 EPA Water Quality Portal field readings (2016–2025). That is a typical value for the month, not a live reading.
How deep is Grand Lake?
- Grand Lake has a maximum depth of 34 feet and an average depth of 19 feet. The lake covers 650.53 acres.
What fish are in Grand Lake?
- Fish species found in Grand Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, walleye, white sucker, yellow bullhead, yellow perch. Grand Lake is located in Stearns County, Minnesota.
When does Grand Lake thaw?
- Grand Lake typically has ice-out around Apr 19. Ice typically forms around Nov 28. The open water season is approximately 223 days.
Are there boat ramps on Grand Lake?
- Grand Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Grand Lake. Public access is listed as yes.
Explore Grand Lake across LakeGrade
Depth, room, public access, and the state wake-sport rules
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
Lakes in the Crow River Watershed, ranked by water quality
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High nutrients, frequent algae, reduced clarity
Minnesota's cleanest and most-polluted lakes, ranked
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Where this data comes from
88 measurements from 3 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
MNPCA88 samples · 2020–2025
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 (3)
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