Graham Lake
Otter Tail County, MinnesotaMesotrophic
Graham Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.
The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. Graham Lake reaches 34 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 217 acres, Graham Lake fits the Minnesota median for monitored lakes, with 2.9 miles of shoreline. Graham Lake ranks 77 of 97 in Otter Tail County — at the lower end of the locally monitored distribution.
Graham Lake has no invasive species recorded in Minnesota state databases as of 2023, though prevention practices still apply at all access points. Walleye are documented at Graham Lake, one of 16 fish species on record for the lake. The lake lacks a documented public access point, so visitor use is limited. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-07-17. Grade methodology: LakeGrade methodology.
Swimming Safety
Good for swimming, clear water with low algae levels
Water Quality Grade: B, Good
Moderate clarity, visible to about 8.4 ft. Phosphorus level: 25.5 µg/L. Trophic State Index: 49.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 8.4 ft | C |
| Phosphorus | 25.5 µg/L | B |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 49 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 34 ft |
| Surface Area | 216.8 acres |
| Shoreline Length | 2.9 mi |
| Littoral Zone | 58% |
| Public Access | No |
Fish Species
Click a species to see all Minnesota and Wisconsin lakes where it is found.
→ Best fishing times for Graham Lake (14-day solunar calendar)
→ Is it safe to eat fish from Graham Lake? (mercury & PFAS guide)
→ Graham Lake fishing regulations (limits, seasons, special rules)
Water Quality Trend: ↓ Declining
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.155 m/yr | 5 |
| Phosphorus | ↓ Declining | +1.8 µg/L/yr | 5 |
Location
County Ranking
Ranked #77 of 97 lakes in Otter Tail County
Nearby Lakes in Otter Tail County
More Minnesota Lake Rankings
State Parks Near Graham Lake
Other Grade B Lakes in Minnesota
Mesotrophic Lakes in Minnesota
DNR Fisheries Survey Summary
2 surveys on file from MN DNR Fisheries. Most recent: 2002-06-10 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Bluegill | 26.80 | 0.31 lb |
| Black Bullhead | 12.98 | 0.57 lb |
| Yellow Perch | 12.00 | 0.1 lb |
| Hybrid Sunfish | 8.28 | 0.21 lb |
| Pumpkinseed | 4.96 | 0.21 lb |
| Northern Pike | 4.83 | 1.93 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
Black Bullhead
Yellow Perch
Hybrid Sunfish
From the 2002-06-10 survey
Graham Lake is a 210-acre mesotrophic (moderately fertile) lake located in north-central Otter Tail County one mile southwest of Frazee, MN. The northern portion of the lake is located within Becker County. Graham Lake is connected to Wimar Lake via a culvert under a township road along the southeast shoreline. The…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Graham Lake. 1 report on file.
- —Fisheries Lake Survey — GrahamFisheries Lake Survey · MN DNR LakeFinder
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Lake details from Minnesota DNR LakeFinder
Most recent sample: 2023-07-17
Monitoring stations: 1