Clearwater Lake
Clearwater Lake in Clearwater County, Minnesota has a water quality grade of A (Excellent). Water clarity: 10 ft visibility. Phosphorus: 16 µg/L. Chlorophyll-a (algae): 3.2 µg/L. Maximum depth: 65 ft. Surface area: 998.8 acres.
- Clarity
- 10 ft
- Typical in August
- 63°F
- Max depth
- 65 ft
- Area
- 999 acres
- Type
- Mesotrophic
- Trend
- ↓ Declining
- Public access
- Yes
- Ice-out
- Apr 22
- Open water
- 224 days
Next lake in Clearwater County
Free interactive depth-contour map of Clearwater Lake, reaching a maximum surveyed depth of 60 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Minnesota DNR.
Clearwater Lake is a 999-acre mesotrophic lake in Clearwater County, Minnesota with a maximum depth of 65 feet. Water quality is graded A based on 2 sampling years through 2025. Overall water quality is declining over recent sampling years. The lake supports 14 documented fish species including black crappie, bluegill, and largemouth bass. Public access is available with 1 public boat landing. Compared to the 36 other monitored lakes in Clearwater County, Clearwater Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-08. Grade methodology: LakeGrade methodology.
Watch Clearwater Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Grade onlyLow algae
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.
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A (Excellent)
Good clarity, visible to about 10 ft. Phosphorus level: 16 µg/L. Chlorophyll-a: 3.2 µg/L. Trophic State Index: 43.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 10 ft | Not graded |
| Phosphorus | 16 µg/L | Good |
| Chlorophyll-a (Algae) | 3.2 µg/L | Good |
| Trophic State Index (TSI) | 43 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Clearwater Lake
Compare lakeside cabins, hotels, and vacation rentals near Clearwater Lake in Clearwater 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 Clearwater 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
Clearwater Lake typically sits around 63°F at the surface in August. Summer average is about 66°F. Usually warmest in Jul (about 72°F) and coldest in May (about 53°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 85 field readings (2010–2025) via the EPA Water Quality Portal. See the full Clearwater Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Clearwater Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was high (111,686 cells/mL) on December 6, 2025.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 65 ft |
| Surface Area | 999 acres |
| Shoreline Length | 8.6 mi |
| Littoral Zone | 34% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Clearwater LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Clearwater Lake
DNR Fisheries Survey Summary
12 surveys on file from MN DNR Fisheries. Most recent: 2025-08-12 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Yellow Perch | 19.98 | 0.13 lb |
| CNM | 17.70 | — |
| BSD | 17.68 | — |
| JND | 13.78 | — |
| Bluegill | 9.53 | 0.2 lb |
| IOD | 8.57 | — |
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.
Yellow Perch
Bluegill
From the 2025-08-12 survey
Minnesota DNR Fisheries IBI program staff conducted an assessment of lakeshore habitat on Clearwater Lake on August 12th, 2025, following the Score the Shore survey protocols. The assessment consisted of 71 survey sites evenly spaced 200 meters around the lake. Assessments were made in three habitat zones: Shoreline…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Clearwater Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — ClearwaterFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Clearwater (1712)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — ClearwaterFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — ClearwaterPublic 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 | -0.105 m/yr | 6 |
| Phosphorus | ↓ Declining | +0.74 µg/L/yr | 6 |
| Chlorophyll-a | ↓ Declining | +0.35 µg/L/yr | 6 |
Ice Season
Historical ice data from Minnesota DNR (18 observations).
Estimated open water season: 224 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2024-04-12 (2024) | 2022-05-07 (2022) |
| Ice-In | 2019-11-13 (2019) | 2001-12-11 (2001) |
Most recent ice-out: 2024-04-12
Reservoir Info (USACE NID)
Clearwater Lake is a man-made reservoir impounded by the Clearwater (completed 1931), built primarily for other on the Clearwater River; gravity-type dam, 21 ft tall and 60 ft long.
- Surface area
- 886 ac
- Normal storage
- 31,170 ac-ft
- Max storage
- 38,963 ac-ft
- Drainage area
- 171 sq mi
- Hazard class
- Low
- Owner
- MNDNR-Fisheries
Source: USACE National Inventory of Dams, NID ID MN00232 · Operator website
EPA Impairment Status
Clearwater 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 MN04-0343-00 · Official waterbody report
County Ranking
Ranked #1 of 37 lakes in Clearwater County
Nearby Lakes in Clearwater County
Frequently asked questions about Clearwater Lake
What is the water quality grade for Clearwater Lake?
- Clearwater Lake in Clearwater County, Minnesota has a water quality grade of A (Excellent). Water clarity: 10 ft visibility. Phosphorus: 16 µg/L. Chlorophyll-a (algae): 3.2 µg/L. Maximum depth: 65 ft. Surface area: 998.8 acres.
Is Clearwater Lake safe to swim in?
- Excellent for swimming, crystal clear water with minimal algae. Clearwater Lake has a water quality grade of A (Excellent). Algae concentration (chlorophyll-a) is 3.2 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Clearwater Lake?
- Clearwater Lake typically sits around 63°F at the surface in August, from 85 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Clearwater Lake?
- Clearwater Lake has a maximum depth of 65 feet. The lake covers 998.8 acres.
What fish are in Clearwater Lake?
- Fish species found in Clearwater Lake include black crappie, bluegill, largemouth bass, northern pike, pumpkinseed, redhorse, rock bass, shorthead redhorse, silver redhorse, tullibee (cisco), walleye, white sucker, yellow bullhead, yellow perch. Clearwater Lake is located in Clearwater County, Minnesota.
When does Clearwater Lake thaw?
- Clearwater Lake typically has ice-out around Apr 22. Ice typically forms around Dec 2. The open water season is approximately 224 days.
Does Clearwater Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Clearwater Lake (clouds, ice, or an off-season gap). The most recent reading was high (111,686 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Clearwater Lake?
- Clearwater Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Clearwater Lake. Public access is listed as yes.
Explore Clearwater Lake across LakeGrade
Fish species and top-graded lakes across Minnesota
Fish species and best lakes in Clearwater County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its grade
Lakes in the Mississippi Headwaters, ranked by water quality
Moderate nutrients, good water quality
Minnesota's cleanest and most-polluted lakes, ranked
More Minnesota Lake Rankings
State Parks Near Clearwater Lake
Other Grade A Lakes in Minnesota
Mesotrophic Lakes in Minnesota
Compare Clearwater Lake With Nearby Lakes
Where this data comes from
86 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA86 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 (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