Elk Lake
Sherburne County, MinnesotaEutrophic
Elk Lake pulls a D on the LakeGrade rubric — phosphorus loading and limited clarity hold it below the Minnesota average. clarity and phosphorus rate similarly, so there is no obvious single lever to pull on watershed management.
A TSI in the eutrophic range signals a lake doing what nutrient-loaded waters do — supporting an active algal community at the cost of clear water. The lake bottoms out at 15 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 362 acres, Elk Lake fits the Minnesota median for monitored lakes, with 4.9 miles of shoreline. Within Sherburne County's 24 graded lakes, Elk Lake ranks 18 — below the local median, though not at the bottom.
Eurasian watermilfoil is established at Elk Lake, which can dampen recreational access and pressure the native plant community. The fishery includes walleye among the lake's 15 documented species — a notable draw for Minnesota anglers. Public access is available — the lake is on the Minnesota PCA public-access list. Ice-out has been recorded 9 times at Elk Lake, with a median around Apr 4. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-09-28. Grade methodology: LakeGrade methodology.
Track Elk Lake
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D, Poor
Very murky, less than 2.5 ft of visibility. Phosphorus level: 74 µg/L. Trophic State Index: 65.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.5 ft | F |
| Phosphorus | 74 µg/L | D |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 65 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 15 ft |
| Average Depth | 7 ft |
| Surface Area | 361.91 acres |
| Shoreline Length | 4.9 mi |
| Littoral Zone | 100% |
| Public Access | Yes |
Fish Species
Click a species to see all Minnesota and Wisconsin lakes where it is found.
→ Best fishing times for Elk Lake (14-day solunar calendar)
→ Is it safe to eat fish from Elk Lake? (mercury & PFAS guide)
→ Elk Lake fishing regulations (limits, seasons, special rules)
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 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.073 m/yr | 5 |
| Phosphorus | ↓ Declining | +2.5 µg/L/yr | 3 |
Ice Season
Historical ice data from Minnesota DNR (19 observations).
Estimated open water season: 233 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2026-03-30 (2026) | 2008-04-21 (2008) |
| Ice-In | 1991-11-02 (1991) | 2021-12-07 (2021) |
Most recent ice-out: 2026-03-30
Location
County Ranking
Ranked #18 of 24 lakes in Sherburne County
Cleaner Lakes Within 30 Miles
Elk Lake holds Grade D. 5 nearby lakes hold higher grades.
- AEast Hunter LakeSherburne County · mi · Two grade letters higher (D → A)
- ASandy LakeSherburne County · mi · Two grade letters higher (D → A)
- AAnn LakeSherburne County · mi · Two grade letters higher (D → A)
- BWest Hunter LakeSherburne County · mi · Two grade letters higher (D → B)
- CBlue LakeIsanti County · mi · Higher grade (D → C)
Nearby Lakes in Sherburne County
More Minnesota Lake Rankings
State Parks Near Elk Lake
Other Grade D Lakes in Minnesota
Eutrophic Lakes in Minnesota
DNR Fisheries Survey Summary
8 surveys on file from MN DNR Fisheries. Most recent: 2017-08-14 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Black Crappie | 49.14 | 0.21 lb |
| Black Bullhead | 27.70 | 0.42 lb |
| Bluntnose Minnow | 24.18 | — |
| Bluegill | 23.91 | 0.16 lb |
| Largemouth Bass | 10.31 | 1.32 lb |
| JND | 8.04 | — |
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.
Black Crappie
Black Bullhead
Bluntnose Minnow
Bluegill
From the 2017-08-14 survey
A targeted survey of the nearshore fish community on Elk Lake was conducted on August 14, 2017 by Fisheries Lake IBI program staff. Sampling stations were evenly spaced around the lake and each was sampled by backpack electrofishing and seining with a 50-foot, where possible. Backpack electrofishing was completed at…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Elk Lake. 3 reports on file.
- —Fisheries Lake Survey — ElkFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — ElkFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — ElkPublic Water Access Sites · MN DNR LakeFinder
Reservoir Info (USACE NID)
Elk Lake is a man-made reservoir impounded by the Elk Lake, built primarily for fish and wildlife pond on the Battle Brook; other-type dam, 9 ft tall and 44 ft long.
- Surface area
- 353 ac
- Normal storage
- 294 ac-ft
- Max storage
- 3,600 ac-ft
- Drainage area
- 42 sq mi
- Hazard class
- Low
- Owner
- MNDNR-Trails
Source: USACE National Inventory of Dams, NID ID MN01329 · Operator website
EPA Impairment Status
Elk Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN71-0055-00 · Official waterbody report
Data Sources
Water quality data from the EPA Water Quality Portal
Impairment status from EPA ATTAINS 303(d) database
Grading methodology based on Metropolitan Council standards
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate
Most recent sample: 2024-09-28
Monitoring stations: 1