Mason Lake
Otter Tail County, Minnesota5,615 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Mason Lake. Here is what has been measured.
- zebra mussel
- 108 ft max depth
- Public access
- Limited data
Mason Lake in Otter Tail County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 21 µg/L. Chlorophyll-a (algae): 16.9 µg/L. Maximum depth: 108 ft. Surface area: 5614.95 acres.
Minnesota DNR's Standard Survey on July 8, 2024 caught 1.67 walleye per gill net at Mason Lake. DNR survey details →
Mason Lake is a 5,615-acre lake in Otter Tail County, Minnesota with a maximum depth of 108 feet. Overall water quality is improving over recent sampling years. The lake supports 17 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 2023-08-02. Methodology: how these readings are compared.
At about 5,600 acres, Mason Lake is large enough that where you stay decides which shore you see most of. It has one public boat landing. The median ice-out date is April 15, which is when the open-water season begins. Vrbo is where to look for cabins and lake homes around Mason Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Mason Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing17 species recorded
- Ice seasonIce-out around Apr 15
- Deep water108 ft surveyed max depth
- Big water5,615 acres
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Mason 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 Mason Lake
These are the measurements Minnesota PCA publishes for Mason Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 3 ft of visibility. Phosphorus 21 µg/L. Chlorophyll-a 16.9 µg/L. TSI 56.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 21µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | 16.9µg/L | Measured, not scored 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. | 56 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Mason Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Standard Survey on July 8, 2024 caught 1.67 walleye per gill net at Mason Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Mason Lake’s water-quality measurements separately, and the water-quality trend over 3 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
11 surveys on file from MN DNR Fisheries. Most recent: 2025-04-21 (Targeted Survey).
11 surveys on file · most recent 2025-04-21 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 33.78 | 3–9 in 2024-07-08 | 0.14 lb |
| Yellow Perch | 11.42 | 5–10 in 2024-07-08 | 0.17 lb |
| Rock Bass | 5.70 | 3–12 in 2024-07-08 | 0.39 lb |
| Pumpkinseed | 5.57 | 3–8 in 2024-07-08 | 0.21 lb |
| Hybrid Sunfish | 5.11 | 3–8 in 2024-07-08 | 0.23 lb |
| Northern Pike | 3.56 | 13–31 in 2024-07-08 | 2.16 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.
Bluegill
Yellow Perch
Rock Bass
Pumpkinseed
From the 2025-04-21 survey
West Battle Lake is a 5,624-acre mesotrophic (moderately fertile) lake located in south-central Otter Tail County. The city of Battle Lake, Minnesota abuts the west shoreline. The immediate watershed is composed primarily of agricultural land interspersed with hardwood woodlots. The maximum depth is 108 feet; however,…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Mason Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — West BattleFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — West Battle (1195)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — West BattleFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — West BattlePublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
108 ft
Surface area
5,615 acres
Shoreline
17.1 mi
Littoral zone
44%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
4 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,329 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- West Battle Lake (East)Public
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Mason Lake
Compare lakeside cabins, hotels, and vacation rentals near Mason 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 Mason Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Follow Mason Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Mason 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 readings over time
3 seasons of samples on record (2023–2025). Calling a direction takes at least 4 years of the same measurement.
Water clarity
Improving3 years
Ice season
Typical ice-out
Apr 15
Earliest Mar 19, 2024 · Latest May 13, 2013
Typical ice-in
Nov 30
Earliest Nov 26, 2002 · Latest Dec 20, 2001
Most recent ice-out
Apr 11
2025
57 observations · Minnesota PCA ice records
Nearby Lakes in Otter Tail County
Frequently asked questions about Mason Lake
Where is Mason Lake?
- Mason 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 Mason Lake?
- Mason Lake in Otter Tail County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 21 µg/L. Chlorophyll-a (algae): 16.9 µg/L. Maximum depth: 108 ft. Surface area: 5614.95 acres.
Is Mason Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Mason Lake?
- Mason Lake has a maximum depth of 108 feet. The lake covers 5614.95 acres.
What fish are in Mason Lake?
- Fish species found in Mason Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, common carp, green sunfish, hybrid sunfish, largemouth bass, muskellunge, northern pike, pumpkinseed, rock bass, walleye, white sucker, yellow bullhead, yellow perch. Mason Lake is located in Otter Tail County, Minnesota.
What did the DNR fisheries survey find at Mason Lake?
- Minnesota DNR's Standard Survey on July 8, 2024 caught 1.67 walleye per gill net at Mason Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Mason Lake’s water-quality measurements separately, and the water-quality trend over 3 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
When does Mason Lake thaw?
- Mason Lake typically has ice-out around Apr 15. Ice typically forms around Nov 30. The open water season is approximately 229 days.
Are there boat ramps on Mason Lake?
- Mason Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include West Battle Lake (East). Public access is listed as yes.
Can I fish at Mason Lake?
- Mason 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 Mason Lake across LakeQuality
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Where this data comes from
4 measurements from 1 monitoring station, 2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA4 samples · 2023
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- 2120 B ~ Color in Water by Visual Comparison
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
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