Deer Lake
Itasca County, Minnesota4,093 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Deer Lake. Here is what has been measured.
- Oligotrophic
- Impaired · Mercury
- 121 ft max depth
- Public access
Deer Lake in Itasca County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 13.1 ft visibility. Phosphorus: 11 µg/L. Chlorophyll-a (algae): 2.1 µg/L. Maximum depth: 121 ft. Surface area: 4093.48 acres.
Minnesota DNR's Standard Survey on July 24, 2023 caught 6.13 walleye per gill net at Deer Lake. DNR survey details →
Free interactive depth-contour map of Deer Lake, reaching a maximum surveyed depth of 100 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Minnesota DNR.
Deer Lake is a 4,093-acre cold, clear oligotrophic lake in Itasca County, Minnesota with a maximum depth of 121 feet (42-foot average). Overall water quality is improving over recent sampling years. The lake supports 17 documented fish species including black crappie, bluegill, and bowfin (dogfish). Public access is available with 2 public boat landings. Compared to the 71 other monitored lakes in Itasca County, Deer Lake ranks #7 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-02. Methodology: how these readings are compared.
Deer Lake covers about 4,100 acres in Itasca County. It has 2 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 27, which is when the open-water season begins. If you are planning to stay, you can search lake houses and cabins around Deer Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.
What Deer Lake is good for
From access and monitoring records, not editorial picks.
- Clear water13.1 ft of visibility
- Boat launch2 documented ramps
- Fishing17 species recorded
- Ice seasonIce-out around Apr 27
- Deep water121 ft surveyed max depth
- Big water4,093 acres
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. Deer Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Deer 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 Deer Lake
These are the measurements Minnesota PCA publishes for Deer 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 13.1 ft. Phosphorus 11 µg/L. Chlorophyll-a 2.1 µg/L. TSI 39.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 13.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 11µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 2.1µg/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. | 39 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Deer Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Deer Lake typically sits around 57°F at the surface in October. Summer average is about 64°F. Usually warmest in Aug (about 67°F) and coldest in May (about 50°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (50°F) to its warmest (67°F).
Typical surface water temperature by month, from 108 field readings (2011–2025) via the EPA Water Quality Portal. See the full Deer Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Deer Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was moderate (77,983 cells/mL) on May 1, 2026.
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 24, 2023 caught 6.13 walleye per gill net at Deer Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Deer 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
13 surveys on file from MN DNR Fisheries. Most recent: 2023-07-24 (Standard Survey).
13 surveys on file · most recent 2023-07-24 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Smallmouth Bass | 13.57 | 2–20 in 2023-07-24 | 1.13 lb |
| Rock Bass | 11.64 | 3–9 in 2023-07-24 | 0.27 lb |
| Yellow Perch | 10.53 | 5–10 in 2023-07-24 | 0.2 lb |
| Bluegill | 7.27 | 3–8 in 2023-07-24 | 0.15 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.
Smallmouth Bass
Rock Bass
Yellow Perch
Bluegill
From the 2023-07-24 survey
Deer Lake is located northeast of Deer River, Minnesota. There is one public access on the southwest part of the lake. There were 373 homes or cabins counted during the last full survey, indicating moderate to high shoreline development. The 2018 lake management plan (LMP) indicated Muskie, Smallmouth Bass and Walleye…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Deer Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — DeerFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Deer (0609)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — DeerFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — DeerPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
121 ft
Average depth
42.1 ft
Surface area
4,093 acres
Shoreline
26.1 mi
Littoral zone
22%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
17 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,302 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Deer LakePublic
- Moose Lake (South)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 Deer Lake
Compare lakeside cabins, hotels, and vacation rentals near Deer Lake in Itasca 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 Deer 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 trip? Cabins and lodging at Deer Lake → · more Minnesota lake trips
Follow Deer Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Deer Lake
Water Quality Trend: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving5 years
Phosphorus
Improving-0.43 µg/L/yr6 years
Chlorophyll-a
Worsening+0.05 µg/L/yr6 years
Ice season
Typical ice-out
Apr 27
Earliest Apr 8, 2017 · Latest May 18, 2013
Typical ice-in
Dec 9
Earliest Nov 30, 2002 · Latest Dec 30, 2023
Most recent ice-out
May 9
2023
54 observations · Minnesota PCA ice records
Reservoir Info (USACE NID)
Deer Lake is a man-made reservoir impounded by the Deer Lake (completed 1938), built primarily for recreation on the Deer River; gravity-type dam, 8 ft tall and 43 ft long.
- Surface area
- 3,958 ac
- Normal storage
- 248,360 ac-ft
- Max storage
- 324,984 ac-ft
- Drainage area
- 45 sq mi
- Hazard class
- Low
- Owner
- MNDNR
Source: USACE National Inventory of Dams, NID ID MN00076 · Operator website
EPA Impairment Status
Deer 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 MN31-0719-00 · Official waterbody report
Nearby Lakes in Itasca County
Frequently asked questions about Deer Lake
Where is Deer Lake?
- Deer Lake is a lake in Itasca County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Deer Lake?
- Deer Lake in Itasca County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 13.1 ft visibility. Phosphorus: 11 µg/L. Chlorophyll-a (algae): 2.1 µg/L. Maximum depth: 121 ft. Surface area: 4093.48 acres.
Is Deer Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Deer 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 Deer Lake?
- Deer Lake typically sits around 57°F at the surface in October, from 108 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Deer Lake?
- Deer Lake has a maximum depth of 121 feet and an average depth of 42.1 feet. The lake covers 4093.48 acres.
What fish are in Deer Lake?
- Fish species found in Deer Lake include black crappie, bluegill, bowfin (dogfish), hybrid sunfish, lake whitefish, largemouth bass, muskellunge, northern pike, pumpkinseed, rock bass, smallmouth bass, tiger muskellunge, tullibee (cisco), walleye, white sucker, yellow bullhead, yellow perch. Deer Lake is located in Itasca County, Minnesota.
What did the DNR fisheries survey find at Deer Lake?
- Minnesota DNR's Standard Survey on July 24, 2023 caught 6.13 walleye per gill net at Deer Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Deer 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 Deer Lake thaw?
- Deer Lake typically has ice-out around Apr 27. Ice typically forms around Dec 9. The open water season is approximately 226 days.
Does Deer Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Deer 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 Deer Lake?
- Deer Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Deer Lake, Moose Lake (South). Public access is listed as yes.
Can I fish at Deer Lake?
- Deer Lake has 2 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.
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Where this data comes from
486 measurements from 8 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
MNPCA486 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H 2 ~ Chlorophyll a-b-c Determination by spectrophotometer
Monitoring station identifiers (8)
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