Maple Lake
Douglas County, Minnesota831 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Maple Lake. Here is what has been measured.
- Mesotrophic
- Impaired · Mercury
- zebra mussel
- 78 ft max depth
- Public access
Maple Lake in Douglas County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 14.1 ft visibility. Phosphorus: 15 µg/L. Chlorophyll-a (algae): 3.1 µg/L. Maximum depth: 78 ft. Surface area: 830.87 acres.
Minnesota DNR's Targeted Survey on August 4, 2025 caught 0.75 walleye per trap net at Maple Lake. DNR survey details →
Free interactive depth-contour map of Maple Lake, reaching a maximum surveyed depth of 70 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Minnesota DNR.
Maple Lake is a 831-acre mesotrophic lake in Douglas County, Minnesota with a maximum depth of 78 feet (16-foot average). 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 3 public boat landings. Compared to the 36 other monitored lakes in Douglas County, Maple Lake ranks #3 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-29. Methodology: how these readings are compared.
Maple Lake covers about 830 acres in Douglas County. It has 3 public boat landings, so a lakefront rental is not the only way to get a boat on the water. The median ice-out date is April 19, which is when the open-water season begins. Vrbo is where to look for cabins and lake homes around Maple Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Maple Lake is good for
From access and monitoring records, not editorial picks.
- Clear water14.1 ft of visibility
- Boat launch3 documented ramps
- Fishing17 species recorded
- Ice seasonIce-out around Apr 19
- Deep water78 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. Maple Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Maple 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 Maple Lake
These are the measurements Minnesota PCA publishes for Maple 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 14.1 ft. Phosphorus 15 µg/L. Chlorophyll-a 3.1 µg/L. TSI 41.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 14.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 15µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 3.1µg/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. | 41 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Maple Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Maple Lake typically sits around 69°F at the surface in September. Summer average is about 73°F. Usually warmest in Jul (about 75°F) and coldest in May (about 58°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (58°F) to its warmest (75°F).
Typical surface water temperature by month, from 46 field readings (2011–2025) via the EPA Water Quality Portal. See the full Maple Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Maple Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was moderate (77,983 cells/mL) on November 16, 2025.
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 August 4, 2025 caught 0.75 walleye per trap net at Maple Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Maple Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
17 surveys on file from MN DNR Fisheries. Most recent: 2025-08-04 (Targeted Survey).
17 surveys on file · most recent 2025-08-04 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 19.51 | 3–8 in 2025-08-04 | 0.19 lb |
| Largemouth Bass | 17.94 | 9–19 in 2025-08-04 | 0.8 lb |
| Bluntnose Minnow | 11.69 | ||
| Green Sunfish | 11.26 | 4 in 2025-08-04 | 0.17 lb |
| Northern Pike | 7.09 | 9–25 in 2025-08-04 | 1.6 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
Largemouth Bass
Green Sunfish
Northern Pike
From the 2025-08-04 survey
A summer trap net survey was conducted in Maple Lake by Lake Biological Monitoring and Assessment program staff beginning on August 4, 2025. Twelve trap nets were set along the shoreline in locations that encompassed multiple habitat types. Trap net sampling captured 12 species of fish, including two species that are…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Maple Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — MapleFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Maple (0935)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — MapleFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — MaplePublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
78 ft
Average depth
16.1 ft
Surface area
831 acres
Shoreline
9.1 mi
Littoral zone
49%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
24 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,375 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Lake Reno (Northeast)Public
- Maple Lake (North)Public
- Maple 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 Maple Lake
Compare lakeside cabins, hotels, and vacation rentals near Maple Lake in Douglas 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 Maple 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 Maple Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Maple 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: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving6 years
Phosphorus
Improving-0.74 µg/L/yr6 years
Chlorophyll-a
Improving-0.2 µg/L/yr6 years
Ice season
Typical ice-out
Apr 19
Earliest Mar 24, 2016 · Latest May 26, 2022
Typical ice-in
Dec 3
Earliest Nov 24, 2007 · Latest Dec 16, 2001
Most recent ice-out
May 26
2022
24 observations · Minnesota PCA ice records
EPA Impairment Status
Maple 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 MN21-0079-00 · Official waterbody report
Nearby Lakes in Douglas County
Frequently asked questions about Maple Lake
Where is Maple Lake?
- Maple Lake is a lake in Douglas County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Maple Lake?
- Maple Lake in Douglas County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 14.1 ft visibility. Phosphorus: 15 µg/L. Chlorophyll-a (algae): 3.1 µg/L. Maximum depth: 78 ft. Surface area: 830.87 acres.
Is Maple Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Maple 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 Maple Lake?
- Maple Lake typically sits around 69°F at the surface in September, from 46 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Maple Lake?
- Maple Lake has a maximum depth of 78 feet and an average depth of 16.1 feet. The lake covers 830.87 acres.
What fish are in Maple Lake?
- Fish species found in Maple Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, common carp, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, smallmouth bass, walleye, white sucker, yellow bullhead, yellow perch. Maple Lake is located in Douglas County, Minnesota.
What did the DNR fisheries survey find at Maple Lake?
- Minnesota DNR's Targeted Survey on August 4, 2025 caught 0.75 walleye per trap net at Maple Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Maple Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
When does Maple Lake thaw?
- Maple Lake typically has ice-out around Apr 19. Ice typically forms around Dec 3. The open water season is approximately 228 days.
Does Maple Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Maple Lake (clouds, ice, or an off-season gap). The most recent reading was moderate (77,983 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Maple Lake?
- Maple Lake has 3 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Lake Reno (Northeast), Maple Lake (North), Maple Lake (East). Public access is listed as yes.
Can I fish at Maple Lake?
- Maple Lake has 3 documented boat landings 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 Maple Lake across LakeQuality
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Where this data comes from
140 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
MNPCA140 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 (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
Ice data from Minnesota DNR Climate