Swan Lake
Otter Tail County, Minnesota749 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Swan Lake. Here is what has been measured.
- Mesotrophic
- Impaired · Mercury
- zebra mussel
- 44 ft max depth
- Public access
Swan Lake in Otter Tail County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 12.1 ft visibility. Phosphorus: 18 µg/L. Chlorophyll-a (algae): 4 µg/L. Maximum depth: 44 ft. Surface area: 748.9 acres.
Minnesota DNR's Standard Survey on July 5, 2022 caught 4.56 walleye per gill net at Swan Lake. DNR survey details →
Swan Lake is a 749-acre mesotrophic lake in Otter Tail County, Minnesota with a maximum depth of 44 feet (13-foot average). Water clarity is improving over recent sampling years. The lake supports 16 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 65 other monitored lakes in Otter Tail County, Swan Lake ranks #22 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-22. Methodology: how these readings are compared.
Swan Lake covers about 750 acres in Otter Tail County. It has one public boat landing. The median ice-out date is April 18, which is when the open-water season begins. Vrbo is where to look for cabins and lake homes around Swan Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Swan Lake is good for
From access and monitoring records, not editorial picks.
- Clear water12.1 ft of visibility
- Boat launch1 documented ramp
- Fishing16 species recorded
- Ice seasonIce-out around Apr 18
- Deep water44 ft surveyed max depth
Swimming conditions
Readings onlyLow algae
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Swan Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Swan 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 Swan Lake
These are the measurements Minnesota PCA publishes for Swan Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 12.1 ft. Phosphorus 18 µg/L. Chlorophyll-a 4 µg/L. TSI 44.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 12.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 18µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 4µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 44 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Swan Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Swan Lake typically sits around 67°F at the surface in September. Summer average is about 74°F. Usually warmest in Jul (about 77°F) and coldest in May (about 60°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (60°F) to its warmest (77°F).
Typical surface water temperature by month, from 35 field readings (2011–2025) via the EPA Water Quality Portal. See the full Swan Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Swan Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was low (11,588 cells/mL) on November 8, 2025.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Minnesota DNR's Standard Survey on July 5, 2022 caught 4.56 walleye per gill net at Swan Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Swan Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
9 surveys on file from MN DNR Fisheries. Most recent: 2022-07-05 (Standard Survey).
9 surveys on file · most recent 2022-07-05 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Largemouth Bass | 29.21 | 2–19 in 2022-07-05 | 1.04 lb |
| Bluegill | 29.08 | 2–7 in 2022-07-05 | 0.1 lb |
| Green Sunfish | 19.60 | 3–4 in 2022-07-05 | 0.05 lb |
| Yellow Bullhead | 7.31 | 6–12 in 2022-07-05 | 0.68 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
Green Sunfish
Yellow Bullhead
From the 2022-07-05 survey
Swan Lake is a 689-acre mesotrophic (moderately fertile) lake located in southwestern Otter Tail County approximately three miles southeast of Fergus Falls, MN. Swan Lake is part of the Pomme de Terre River Watershed. The Pomme de Terre River outlet is located along the south shoreline of the lake and is unnavigable.…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Swan Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — SwanFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — SwanFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — SwanPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
44 ft
Average depth
13 ft
Surface area
749 acres
Shoreline
9.2 mi
Littoral zone
50%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
13 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,184 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Swan 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 Swan Lake
Compare lakeside cabins, hotels, and vacation rentals near Swan 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 Swan 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 →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Swan 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.
Water Quality Trend: Stable
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving6 years
Phosphorus
Worsening+0.59 µg/L/yr6 years
Chlorophyll-a
Stable+0.05 µg/L/yr6 years
Ice season
Typical ice-out
Apr 18
Earliest Mar 11, 2024 · Latest May 9, 2013
Typical ice-in
Nov 30
Earliest Nov 12, 2018 · Latest Dec 10, 2016
Most recent ice-out
Mar 11
2024
24 observations · Minnesota PCA ice records
EPA Impairment Status
Swan 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 MN56-0781-00 · Official waterbody report
Nearby Lakes in Otter Tail County
Frequently asked questions about Swan Lake
Where is Swan Lake?
- Swan 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 Swan Lake?
- Swan Lake in Otter Tail County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 12.1 ft visibility. Phosphorus: 18 µg/L. Chlorophyll-a (algae): 4 µg/L. Maximum depth: 44 ft. Surface area: 748.9 acres.
Is Swan Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Swan 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 Swan Lake?
- Swan Lake typically sits around 67°F at the surface in September, from 35 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Swan Lake?
- Swan Lake has a maximum depth of 44 feet and an average depth of 13 feet. The lake covers 748.9 acres.
What fish are in Swan Lake?
- Fish species found in Swan Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, common carp, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, walleye, white sucker, yellow bullhead, yellow perch. Swan Lake is located in Otter Tail County, Minnesota.
What did the DNR fisheries survey find at Swan Lake?
- Minnesota DNR's Standard Survey on July 5, 2022 caught 4.56 walleye per gill net at Swan Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Swan Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
When does Swan Lake thaw?
- Swan Lake typically has ice-out around Apr 18. Ice typically forms around Nov 30. The open water season is approximately 226 days.
Does Swan Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Swan Lake (clouds, ice, or an off-season gap). The most recent reading was low (11,588 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Swan Lake?
- Swan Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Swan Lake. Public access is listed as yes.
Can I fish at Swan Lake?
- Swan 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 Swan Lake across LakeQuality
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Fish species and best lakes in Otter Tail County
Species activity outlook by water temperature and season
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Top lakes and where to stay in the Otter Tail County area
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Minnesota's cleanest lakes, ranked on agency measurements
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Where this data comes from
133 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
MNPCA133 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)
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
Ice data from Minnesota DNR Climate