Ethel Lake
Ethel Lake in Otter Tail County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 14.6 ft visibility. Maximum depth: 64 ft. Surface area: 191.12 acres.
- Clarity
- 14.6 ft
- Typical in August
- 74°F
- Max depth
- 64 ft
- Area
- 191 acres
- Trend
- → Stable
- Public access
- Yes
- Ice-out
- Apr 15
- Open water
- 237 days
Next lake in Otter Tail County
Why Ethel Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Ethel Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Ethel Lake is a 191-acre lake in Otter Tail County, Minnesota with a maximum depth of 64 feet. The lake supports 13 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 2025-09-21. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Ethel Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Good clarity, visible to about 14.6 ft. Trophic State Index: 39.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 14.6 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 39 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Ethel Lake
Compare lakeside cabins, hotels, and vacation rentals near Ethel 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 Ethel Lake
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Water Temperature
Ethel Lake typically sits around 74°F at the surface in August. Summer average is about 75°F. Usually warmest in Jul (about 78°F) and coldest in May (about 57°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 15 field readings (2011–2025) via the EPA Water Quality Portal. See the full Ethel Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 64 ft |
| Surface Area | 191 acres |
| Shoreline Length | 3.2 mi |
| Littoral Zone | 36% |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Ethel LakePublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Ethel 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.
DNR Fisheries Survey Summary
6 surveys on file from MN DNR Fisheries. Most recent: 2025-07-16 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Bluntnose Minnow | 74.06 | — |
| Bluegill | 29.58 | 0.2 lb |
| MMS | 24.11 | — |
| Spottail Shiner | 21.53 | — |
| IOD | 14.82 | — |
| Yellow Bass | 9.79 | 0.51 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.
Bluegill
Yellow Bass
From the 2025-07-16 survey
A targeted survey of nearshore fish species in Ethel Lake was conducted on July 16 -July 17, 2025, by Lake Biological Monitoring and Assessment (LBMA) Program staff. Sampling sites were evenly spaced around the lake, and each was sampled by backpack electrofishing and seining with a 50-foot or 15-foot seine, where…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Ethel Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — EthelFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Ethel (0965)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — EthelFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — EthelPublic Water Access Sites · MN DNR LakeFinder
Water Quality Trend: → Stable
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | +0.047 m/yr | 6 |
Ice Season
Historical ice data from Minnesota DNR (8 observations).
Estimated open water season: 237 days
| Earliest | Latest | |
|---|---|---|
| Ice-Out | 2005-04-10 (2005) | 2008-05-01 (2008) |
| Ice-In | 2003-11-11 (2003) | 2004-12-14 (2004) |
Most recent ice-out: 2008-05-01
EPA Impairment Status
Ethel Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN56-0240-00 · Official waterbody report · Matched by proximity (2.81 km)
Graded lakes near Ethel Lake
Ethel Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Otter Tail County
Frequently asked questions about Ethel Lake
What is the water quality grade for Ethel Lake?
- Ethel Lake in Otter Tail County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 14.6 ft visibility. Maximum depth: 64 ft. Surface area: 191.12 acres.
Is Ethel Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Ethel Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
What is the water temperature of Ethel Lake?
- Ethel Lake typically sits around 74°F at the surface in August, from 15 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Ethel Lake?
- Ethel Lake has a maximum depth of 64 feet. The lake covers 191.12 acres.
What fish are in Ethel Lake?
- Fish species found in Ethel Lake include black bullhead, black crappie, bluegill, brown bullhead, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, walleye, white sucker, yellow bullhead, yellow perch. Ethel Lake is located in Otter Tail County, Minnesota.
When does Ethel Lake thaw?
- Ethel Lake typically has ice-out around Apr 15. Ice typically forms around Dec 8. The open water season is approximately 237 days.
Are there boat ramps on Ethel Lake?
- Ethel Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Ethel Lake. Public access is listed as yes.
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Where this data comes from
55 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA55 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (1)
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