Preston Lake
Renville County, Minnesota655 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Preston Lake. Here is what has been measured.
- Eutrophic
- Impaired · Mercury
- 11 ft max depth
- Public access
Preston Lake in Renville County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5 ft visibility. Phosphorus: 222 µg/L. Chlorophyll-a (algae): 39.2 µg/L. Maximum depth: 11 ft. Surface area: 654.96 acres.
Minnesota DNR's Targeted Survey on July 7, 2025 caught 2.67 walleye per gill net at Preston Lake. Length samples in the latest survey that recorded them ran 10–27 inches. DNR survey details →
Preston Lake is a 655-acre productive, nutrient-rich eutrophic lake in Renville County, Minnesota with a maximum depth of 11 feet (7-foot average). Overall water quality is improving over recent sampling years. The lake supports 13 documented fish species including bigmouth buffalo, black bullhead, and black crappie. Public access is available with 1 public boat landing. Compared to the 1 other monitored lakes in Renville County, Preston Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-15. Methodology: how these readings are compared.
What Preston Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing13 species recorded
- Ice seasonIce-out around Apr 16
Swimming conditions
Readings onlyRecreation use not supported
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. Preston Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Preston 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 Preston Lake
These are the measurements Minnesota PCA publishes for Preston Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 5 ft. Phosphorus 222 µg/L. Chlorophyll-a 39.2 µg/L. TSI 68.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 222µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 39.2µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 68 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Preston Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Preston Lake typically sits around 70°F at the surface in September. Summer average is about 73°F. Usually warmest in Jul (about 80°F) and coldest in Jun (about 65°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (65°F) to its warmest (80°F).
Typical surface water temperature by month, from 8 field readings (2016–2025) via the EPA Water Quality Portal. See the full Preston Lake water temperature breakdown →
Minnesota DNR's Targeted Survey on July 7, 2025 caught 2.67 walleye per gill net at Preston Lake. Length samples in the latest survey that recorded them ran 10–27 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Preston 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: 2025-07-07 (Targeted Survey).
13 surveys on file · most recent 2025-07-07 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Black Bullhead | 82.53 | 5–9 in 2025-07-07 | 0.26 lb |
| Common Carp | 21.31 | 22–29 in 2025-07-07 | 4.9 lb |
| Brown Bullhead | 19.29 | 12 in 2010-07-26 | 0.79 lb |
| Fathead Minnow | 13.41 | ||
| Walleye | 12.86 | 10–27 in 2025-07-07 | 1.36 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.
Black Bullhead
Common Carp
Brown Bullhead
Walleye
From the 2025-07-07 survey
Preston is a moderate-sized lake (655 acres) located northeast of the Town of Buffalo Lake in Renville County. A state-owned access with gravel parking and a single cement boat ramp is present along the west shore. There is a fishing pier present at the public access. Preston has approximately five miles of shoreline…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Preston Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — PrestonFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — PrestonFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — PrestonPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
11 ft
Average depth
7 ft
Surface area
655 acres
Shoreline
5.4 mi
Littoral zone
100%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
7 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,033 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Preston LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Preston Lake
Compare lakeside cabins, hotels, and vacation rentals near Preston Lake in Renville 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Preston Lake are listed below.
Top-rated places to stay near Preston 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 whole trip? See where to stay at Minnesota’s top lakes →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Preston Lake
Water Quality Trend: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving5 years
Phosphorus
Improving-10.23 µg/L/yr6 years
Chlorophyll-a
Worsening+2.11 µg/L/yr6 years
Ice season
Typical ice-out
Apr 16
Earliest Mar 6, 2017 · Latest May 1, 2018
Most recent ice-out
May 1
2018
6 observations · Minnesota PCA ice records
EPA Impairment Status
Preston 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, Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN65-0002-00 · Official waterbody report
Nearby Lakes in Renville County
Frequently asked questions about Preston Lake
Where is Preston Lake?
- Preston Lake is a lake in Renville County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Preston Lake?
- Preston Lake in Renville County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5 ft visibility. Phosphorus: 222 µg/L. Chlorophyll-a (algae): 39.2 µg/L. Maximum depth: 11 ft. Surface area: 654.96 acres.
Is Preston Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Preston Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Preston Lake?
- Preston Lake typically sits around 70°F at the surface in September, from 8 EPA Water Quality Portal field readings (2016–2025). That is a typical value for the month, not a live reading.
How deep is Preston Lake?
- Preston Lake has a maximum depth of 11 feet and an average depth of 7 feet. The lake covers 654.96 acres.
What fish are in Preston Lake?
- Fish species found in Preston Lake include bigmouth buffalo, black bullhead, black crappie, bluegill, common carp, green sunfish, hybrid sunfish, largemouth bass, northern pike, orangespotted sunfish, walleye, white sucker, yellow perch. Preston Lake is located in Renville County, Minnesota.
What did the DNR fisheries survey find at Preston Lake?
- Minnesota DNR's Targeted Survey on July 7, 2025 caught 2.67 walleye per gill net at Preston Lake. Length samples in the latest survey that recorded them ran 10–27 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Preston 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 Preston Lake thaw?
- Preston Lake typically has ice-out around Apr 16.
Are there boat ramps on Preston Lake?
- Preston Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Preston Lake. Public access is listed as yes.
Can I fish at Preston Lake?
- Preston Lake has 1 documented boat landing 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.
Explore Preston Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
Fish species and the cleanest lakes across Minnesota
Fish species and best lakes in Renville County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Lakes in the Minnesota River Watershed, ranked by water quality
Minnesota's cleanest lakes, ranked on agency measurements
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State Parks Near Preston Lake
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Compare Preston Lake With Nearby Lakes
Where this data comes from
69 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
MNPCA69 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (1)
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