Skip to main content
LakeQuality

Deer Lake

A
Grade A — Excellent
Excellent · #7 of 72 lakes in the county · 13.1 ft clear · Oligotrophic · 4,093 acres
Oligotrophic

Deer Lake in Itasca County, Minnesota has a water quality grade of A (Excellent). 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.

Clarity
13.1 ft
Typical in August
67°F
Max depth
121 ft
Area
4,093 acres
Type
Oligotrophic
Trend
Improving
Public access
Yes
Ice-out
Apr 27
Open water
226 days

Next lake in Itasca County

NRLittle Moose Lake8 ft clear · Itasca CountyView →
Loading map…

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). Water quality is graded A based on 2 sampling years through 2025. 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. Grade methodology: LakeGrade methodology.

Watch Deer Lake water quality

Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.

Swimming Safety

Grade only

Low algae

Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.

Excellent for swimming, crystal clear water with minimal algae

Compare the safest swimming lakes near Grand Rapids

Get alerts for Deer Lake

Water Quality Grade: A (Excellent)

Good clarity, visible to about 13.1 ft. Phosphorus level: 11 µg/L. Chlorophyll-a: 2.1 µg/L. Trophic State Index: 39.

MetricValueGrade
Water Clarity (Secchi Depth)13.1 ftNot graded
Phosphorus11 µg/LGood
Chlorophyll-a (Algae)2.1 µg/LGood
Trophic State Index (TSI)39Oligotrophic

Low nutrients, clear water, excellent for swimming

Where to stay 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

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

Water Temperature

Deer Lake typically sits around 67°F at the surface in August. 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.

Jan
Feb
Mar
Apr
May
50°
Jun
59°
Jul
66°
Aug
67°
Sep
62°
Oct
57°
Nov
Dec

Typical surface water temperature by month, from 108 field readings (20112025) via the EPA Water Quality Portal. See the full Deer Lake water temperature breakdown →

Blue-Green Algae (Cyanobacteria)

No current satellite reading

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 ↗

Lake Details

CharacteristicValue
Maximum Depth121 ft
Average Depth42.1 ft
Surface Area4,093 acres
Shoreline Length26.1 mi
Littoral Zone22%
Public AccessYes

Lake Size & Watershed

Watershed (drainage) area
17 sq mi
Elevation
1,302 ft

Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).

Recreation & Access

2
Boat Landings
Yes
Public Access
  • Deer LakePublic
  • Moose Lake (South)Public

Fish Species

Click a species to see every graded lake where it is documented.

Fishing Deer Lake

DNR Fisheries Survey Summary

13 surveys on file from MN DNR Fisheries. Most recent: 2023-07-24 (Standard Survey).

Top Species by Catch Rate

SpeciesAvg CPUEAvg Weight
Smallmouth Bass13.571.13 lb
Rock Bass11.640.27 lb
CNM11.26
Yellow Perch10.530.2 lb
MTS8.88
Bluegill7.270.15 lb

CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.

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

227 fish · 220 in · 2023-07-24
43220trophy 182468101214161820

Rock Bass

257 fish · 39 in · 2023-07-24
613103456789

Yellow Perch

160 fish · 510 in · 2023-07-24
623105678910

Bluegill

328 fish · 38 in · 2023-07-24
98490345678

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…

Source: MN DNR LakeFinder Fisheries Lake Survey

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).

Based on 6 years of monitoring data (2020-2025).

MetricTrendChange/YearYears
Water Clarity Improving+0.165 m/yr5
Phosphorus Improving-0.43 µg/L/yr6
Chlorophyll-a Declining+0.05 µg/L/yr6
See year-by-year chart →

Ice Season

Historical ice data from Minnesota DNR (54 observations).

Typical Ice-Out
Apr 27
Typical Ice-In
Dec 9

Estimated open water season: 226 days

EarliestLatest
Ice-Out2017-04-08 (2017)2013-05-18 (2013)
Ice-In2002-11-30 (2002)2023-12-30 (2023)

Most recent ice-out: 2023-05-09

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

Mercury

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit MN31-0719-00 · Official waterbody report

County Ranking

Ranked #7 of 72 lakes in Itasca County

Nearby Lakes in Itasca County

Frequently asked questions about Deer Lake

What is the water quality grade for Deer Lake?

Deer Lake in Itasca County, Minnesota has a water quality grade of A (Excellent). 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?

Excellent for swimming, crystal clear water with minimal algae. Deer Lake has a water quality grade of A (Excellent). Algae concentration (chlorophyll-a) is 2.1 µg/L. Always check local health department advisories before swimming.

What is the water temperature of Deer Lake?

Deer Lake typically sits around 67°F at the surface in August, 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.

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.

Compare Deer Lake With Nearby Lakes

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 WaterMNPCA486 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)

Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated 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