Skip to main content
LakeQuality

Round Lake

A
Grade A — Excellent
Excellent · #3 of 66 lakes in the county · 11.2 ft clear · Mesotrophic · 158 acres
Mesotrophic

Round Lake in Otter Tail County, Minnesota has a water quality grade of A (Excellent). Water clarity: 11.2 ft visibility. Phosphorus: 19 µg/L. Chlorophyll-a (algae): 4.8 µg/L. Maximum depth: 24 ft. Surface area: 157.63 acres.

Clarity
11.2 ft
Max depth
24 ft
Area
158 acres
Type
Mesotrophic
Trend
Stable
Public access
Yes

Next lake in Otter Tail County

ADeer Lake12.3 ft clear · Otter Tail CountyView →
Loading map…

Round Lake is a 158-acre mesotrophic lake in Otter Tail County, Minnesota with a maximum depth of 24 feet. Water quality is graded A based on 2 sampling years through 2025. Water clarity is improving over recent sampling years. Limited fish-species data available. Public access is available with 2 public boat landings. Compared to the 65 other monitored lakes in Otter Tail County, Round Lake ranks #3 for water quality.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-22. Grade methodology: LakeGrade methodology.

Watch Round 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 Detroit Lakes

Get alerts for Round Lake

Water Quality Grade: A (Excellent)

Good clarity, visible to about 11.2 ft. Phosphorus level: 19 µg/L. Chlorophyll-a: 4.8 µg/L. Trophic State Index: 45.

MetricValueGrade
Water Clarity (Secchi Depth)11.2 ftNot graded
Phosphorus19 µg/LGood
Chlorophyll-a (Algae)4.8 µg/LGood
Trophic State Index (TSI)45Mesotrophic

Moderate nutrients, good water quality

Where to stay near Round Lake

Compare lakeside cabins, hotels, and vacation rentals near Round 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 Round 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 whole trip? See where to stay at Minnesota’s top lakes →

Lake Details

CharacteristicValue
Maximum Depth24 ft
Surface Area158 acres
Shoreline Length2 mi
Littoral Zone81%
Public AccessYes

Lake Size & Watershed

Watershed (drainage) area
0 sq mi
Elevation
1,316 ft

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

Recreation & Access

2
Boat Landings
Yes
Public Access
  • Riverside (West)Public
  • Highway 72 BridgePublic

Fishing Round Lake

DNR Fisheries Survey Summary

2 surveys on file from MN DNR Fisheries. Most recent: 1991-08-12 (Standard Survey).

Top Species by Catch Rate

SpeciesAvg CPUEAvg Weight
Pumpkinseed89.290.07 lb
Black Bullhead41.150.21 lb
Yellow Perch39.790.09 lb
Bluegill35.700.13 lb
Green Sunfish20.340.09 lb
Hybrid Sunfish9.700.11 lb

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

From the 1991-08-12 survey

Round lake is in class 38 of the MN DNR lake classification system. Other area lakes included in this class are: Block, Buchanan, Elbow, and Sand. Northern pike were not represented in the gill net sample. Pike gill net CPUE in the 1975 survey was 2.5 per net. Black bullhead abundance declined from 118.0 per gill net…

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 Round Lake. 2 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+0.07 m/yr6
Phosphorus Stable-0.33 µg/L/yr6
Chlorophyll-a Declining+0.3 µg/L/yr6
See year-by-year chart →

County Ranking

Ranked #3 of 66 lakes in Otter Tail County

Nearby Lakes in Otter Tail County

Frequently asked questions about Round Lake

What is the water quality grade for Round Lake?

Round Lake in Otter Tail County, Minnesota has a water quality grade of A (Excellent). Water clarity: 11.2 ft visibility. Phosphorus: 19 µg/L. Chlorophyll-a (algae): 4.8 µg/L. Maximum depth: 24 ft. Surface area: 157.63 acres.

Is Round Lake safe to swim in?

Excellent for swimming, crystal clear water with minimal algae. Round Lake has a water quality grade of A (Excellent). Algae concentration (chlorophyll-a) is 4.8 µg/L. Always check local health department advisories before swimming.

How deep is Round Lake?

Round Lake has a maximum depth of 24 feet. The lake covers 157.63 acres.

Are there boat ramps on Round Lake?

Round Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Riverside (West), Highway 72 Bridge. Public access is listed as yes.

Mesotrophic Lakes in Minnesota

Where this data comes from

64 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 WaterMNPCA64 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 (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

Lake size & watershed from HydroLAKES (HydroSHEDS)

Lake details from Minnesota DNR LakeFinder

Named boat-access points from the USGS National Boat Ramps inventory