Sewell Lake
Otter Tail County, Minnesota369 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Sewell Lake. Here is what has been measured.
- Impaired · Mercury
- 52 ft max depth
- Public access
- Limited data
Sewell Lake in Otter Tail County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5 ft visibility. Maximum depth: 52 ft. Surface area: 368.8 acres.
Minnesota DNR's Targeted Survey on June 24, 2024 caught 0.56 walleye per trap net at Sewell Lake. DNR survey details →
Sewell Lake is a 369-acre lake in Otter Tail County, Minnesota with a maximum depth of 52 feet. The lake supports 13 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-08-22. Methodology: how these readings are compared.
Sewell Lake covers about 370 acres in Otter Tail County. It has one public boat landing. Vrbo is where to look for cabins and lake homes around Sewell Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Sewell Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing13 species recorded
- Deep water52 ft surveyed max depth
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Sewell Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Sewell Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Sewell Lake
These are the measurements Minnesota PCA publishes for Sewell Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 5 ft. TSI 54.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 54 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Sewell Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Sewell Lake typically sits around 61°F at the surface in September. Summer average is about 69°F. Usually warmest in Aug (about 72°F) and coldest in May (about 59°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (59°F) to its warmest (72°F).
Typical surface water temperature by month, from 39 field readings (2010–2025) via the EPA Water Quality Portal. See the full Sewell Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Sewell Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was high (139,316 cells/mL) on July 4, 2026.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Minnesota DNR's Targeted Survey on June 24, 2024 caught 0.56 walleye per trap net at Sewell Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Sewell Lake’s water-quality measurements separately, and the water-quality trend over 5 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
10 surveys on file from MN DNR Fisheries. Most recent: 2024-06-24 (Targeted Survey).
10 surveys on file · most recent 2024-06-24 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Largemouth Bass | 39.95 | 5–18 in 2024-06-24 | 1.74 lb |
| Bluegill | 38.59 | 3–8 in 2024-06-24 | 0.16 lb |
| Spottail Shiner | 17.55 | ||
| Fathead Minnow | 16.99 | ||
| Yellow Perch | 13.79 | 5 in 2024-06-24 | 0.1 lb |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
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.
Largemouth Bass
Bluegill
Yellow Perch
From the 2024-06-24 survey
A targeted survey of nearshore fish species in Sewell Lake was conducted on June 24th-25th, 2024, by Index of Biological Integrity (IBI) Program. Sampling sites were evenly spaced around the lake, and each was sampled by backpack electrofishing and seining with a 50-foot or 15-foot seine, where possible. Backpack…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Sewell Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — SewellFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Sewell (1054)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — SewellFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — SewellPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
52 ft
Surface area
369 acres
Shoreline
5.6 mi
Littoral zone
46%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
7 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,289 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Sewell LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Sewell Lake
Compare lakeside cabins, hotels, and vacation rentals near Sewell Lake in Otter Tail 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 Sewell Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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 →
Follow Sewell Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Sewell Lake
Water Quality Trend: Stable
Based on 5 years of monitoring (2020–2025).
Water clarity
Stable5 years
EPA Impairment Status
Sewell Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN56-0408-00 · Official waterbody report
Nearby Lakes in Otter Tail County
Frequently asked questions about Sewell Lake
Where is Sewell Lake?
- Sewell Lake is a lake in Otter Tail County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Sewell Lake?
- Sewell Lake in Otter Tail County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5 ft visibility. Maximum depth: 52 ft. Surface area: 368.8 acres.
Is Sewell Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Sewell Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
What is the water temperature of Sewell Lake?
- Sewell Lake typically sits around 61°F at the surface in September, from 39 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Sewell Lake?
- Sewell Lake has a maximum depth of 52 feet. The lake covers 368.8 acres.
What fish are in Sewell Lake?
- Fish species found in Sewell Lake include black bullhead, black crappie, bluegill, brown bullhead, common carp, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, walleye, yellow bullhead, yellow perch. Sewell Lake is located in Otter Tail County, Minnesota.
What did the DNR fisheries survey find at Sewell Lake?
- Minnesota DNR's Targeted Survey on June 24, 2024 caught 0.56 walleye per trap net at Sewell Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Sewell Lake’s water-quality measurements separately, and the water-quality trend over 5 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
Does Sewell Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Sewell Lake (clouds, ice, or an off-season gap). The most recent reading was high (139,316 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Sewell Lake?
- Sewell Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Sewell Lake. Public access is listed as yes.
Can I fish at Sewell Lake?
- Sewell Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Sewell Lake across LakeQuality
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Where this data comes from
48 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
MNPCA47 samples · 2020–2025 - Minnesota Department of Agriculture - Pesticide Monitoring
MNDA_PESTICIDE1 sample · 2022
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (2)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from 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