Peterson Lake
Peterson Lake in Clearwater County, Minnesota has a water quality grade of A (Excellent). Water clarity: 11.3 ft visibility. Phosphorus: 22 µg/L. Chlorophyll-a (algae): 4.9 µg/L. Maximum depth: 70 ft. Surface area: 98.87 acres.
- Clarity
- 11.3 ft
- Typical in August
- 57°F
- Max depth
- 70 ft
- Area
- 99 acres
- Type
- Mesotrophic
- Trend
- ↓ Declining
- Public access
- Yes
Next lake in Clearwater County
Peterson Lake is a 99-acre mesotrophic lake in Clearwater County, Minnesota with a maximum depth of 70 feet. Water quality is graded A based on 2 sampling years through 2025. Overall water quality is declining over recent sampling years. Limited fish-species data available. Public access is available with 2 public boat landings. Compared to the 36 other monitored lakes in Clearwater County, Peterson Lake ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-09. Grade methodology: LakeGrade methodology.
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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 11.3 ft. Phosphorus level: 22 µg/L. Chlorophyll-a: 4.9 µg/L. Trophic State Index: 46.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 11.3 ft | Not graded |
| Phosphorus | 22 µg/L | Good |
| Chlorophyll-a (Algae) | 4.9 µg/L | Good |
| Trophic State Index (TSI) | 46 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Peterson Lake
Compare lakeside cabins, hotels, and vacation rentals near Peterson 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.
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Water Temperature
Peterson Lake typically sits around 57°F at the surface in August. Summer average is about 56°F. Usually warmest in Jul (about 58°F) and coldest in May (about 51°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 189 field readings (2011–2019) via the EPA Water Quality Portal. See the full Peterson Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 70 ft |
| Surface Area | 99 acres |
| Shoreline Length | 2.9 mi |
| Littoral Zone | 32% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Peterson LakePublic
- Deep LakePublic
Fishing Peterson Lake
DNR Fisheries Survey Summary
3 surveys on file from MN DNR Fisheries. Most recent: 1998-06-17 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Black Bullhead | 68.99 | 0.13 lb |
| Yellow Perch | 17.90 | 0.23 lb |
| Northern Pike | 5.45 | 1.2 lb |
| Bluegill | 3.50 | 0.61 lb |
| Pumpkinseed | 1.41 | 0.29 lb |
| Brown Bullhead | 0.67 | 0.39 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
Yellow Perch
Northern Pike
Bluegill
From the 1998-06-17 survey
Peterson Lake is in fisheries lake class 28 which is a group of small lakes with a regular shoreline and hard, clear water. Most Bemidji area lakes in this class are in Clearwater County. The list includes Lone, Lomond, Walker Brook, Deep, First, Second, and Falk lakes. The latest lake management plan, written in…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Peterson Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — PetersonFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Peterson (1700)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — PetersonPublic 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 | → Stable | -0.033 m/yr | 6 |
| Phosphorus | ↓ Declining | +0.46 µg/L/yr | 6 |
| Chlorophyll-a | ↓ Declining | +0.11 µg/L/yr | 6 |
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Peterson Lake under Clean Water Act (NPDES) discharge permits.
- Enbridge Energy Ltd - ClearbrookClearbrook · 2 mi away · NPDES MN0056324
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.
County Ranking
Ranked #4 of 37 lakes in Clearwater County
Nearby Lakes in Clearwater County
Frequently asked questions about Peterson Lake
What is the water quality grade for Peterson Lake?
- Peterson Lake in Clearwater County, Minnesota has a water quality grade of A (Excellent). Water clarity: 11.3 ft visibility. Phosphorus: 22 µg/L. Chlorophyll-a (algae): 4.9 µg/L. Maximum depth: 70 ft. Surface area: 98.87 acres.
Is Peterson Lake safe to swim in?
- Excellent for swimming, crystal clear water with minimal algae. Peterson Lake has a water quality grade of A (Excellent). Algae concentration (chlorophyll-a) is 4.9 µg/L. Always check local health department advisories before swimming.
What is the water temperature of Peterson Lake?
- Peterson Lake typically sits around 57°F at the surface in August, from 189 EPA Water Quality Portal field readings (2011–2019). That is a typical value for the month, not a live reading.
How deep is Peterson Lake?
- Peterson Lake has a maximum depth of 70 feet. The lake covers 98.87 acres.
Are there boat ramps on Peterson Lake?
- Peterson Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Peterson Lake, Deep Lake. Public access is listed as yes.
Explore Peterson Lake across LakeGrade
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Where this data comes from
83 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
MNPCA83 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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory