Caroline Lake
Wright County, Minnesota137 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Caroline Lake. Here is what has been measured.
- Eutrophic
- Impaired · Nutrients (phosphorus, nitrogen)
- Eurasian watermilfoil
- 45 ft max depth
Caroline Lake in Wright County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3.5 ft visibility. Phosphorus: 53 µg/L. Chlorophyll-a (algae): 31.6 µg/L. Maximum depth: 45 ft. Surface area: 137.15 acres.
Minnesota DNR's Standard Survey on July 1, 2019 caught 1.83 walleye per gill net at Caroline Lake. DNR survey details →
Caroline Lake is a 137-acre productive, nutrient-rich eutrophic lake in Wright County, Minnesota with a maximum depth of 45 feet (15-foot average). Overall water quality is declining over recent sampling years. The lake supports 17 documented fish species including black bullhead, black crappie, and bluegill. No public access — the lake is private or restricted. Compared to the 50 other monitored lakes in Wright County, Caroline Lake ranks #39 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-10. Methodology: how these readings are compared.
What Caroline Lake is good for
From access and monitoring records, not editorial picks.
- Fishing17 species recorded
- Ice seasonIce-out around Apr 11
- Deep water45 ft surveyed max depth
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. Caroline Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Caroline 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 Caroline Lake
These are the measurements Minnesota PCA publishes for Caroline 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 3.5 ft. Phosphorus 53 µg/L. Chlorophyll-a 31.6 µg/L. TSI 62.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 53µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 31.6µg/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. | 62 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Caroline Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Caroline Lake typically sits around 61°F at the surface in September. Summer average is about 63°F. Usually warmest in Mar (about 69°F) and coldest in May (about 54°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (54°F) to its warmest (69°F).
Typical surface water temperature by month, from 354 field readings (2010–2025) via the EPA Water Quality Portal. See the full Caroline Lake water temperature breakdown →
Minnesota DNR's Standard Survey on July 1, 2019 caught 1.83 walleye per gill net at Caroline Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Caroline Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
7 surveys on file from MN DNR Fisheries. Most recent: 2019-07-01 (Standard Survey).
7 surveys on file · most recent 2019-07-01 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Black Bullhead | 22.24 | 11–13 in 2014-06-30 | 0.65 lb |
| Bluegill | 13.01 | 3–7 in 2019-07-01 | 0.22 lb |
| Black Crappie | 10.68 | 3–11 in 2019-07-01 | 0.31 lb |
| Largemouth Bass | 6.57 | 10–18 in 2019-07-01 | 1.65 lb |
| Northern Pike | 2.77 | 17–34 in 2019-07-01 | 3.14 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
Bluegill
Black Crappie
Largemouth Bass
From the 2019-07-01 survey
Lake Caroline is a 126 acre lake located along the Clearwater River in Wright County east of the city of Fairhaven. The lake has a surface area of 126 acres with a maximum depth of 45 feet and a mid-summer secchi depth of 5 feet. Lake Caroline has no public access; however it can be accessed from Lake Augusta via the…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Caroline Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — CarolineFisheries Lake Survey · MN DNR LakeFinder
Lake Details
Max depth
45 ft
Average depth
15 ft
Surface area
137 acres
Shoreline
3.1 mi
Littoral zone
33%
Share shallower than 15 ft
Public access
No
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
90 sq mi
HydroLAKES / HydroSHEDS
Elevation
991 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Caroline Lake
Compare lakeside cabins, hotels, and vacation rentals near Caroline Lake in Wright 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 Caroline Lake are listed below.
Top-rated places to stay near Caroline Lake
Prices for Oct 16–18, 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 Caroline 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.
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving6 years
Phosphorus
Worsening+9.64 µg/L/yr5 years
Chlorophyll-a
Worsening+0.92 µg/L/yr5 years
Ice season
Typical ice-out
Apr 11
Earliest Mar 14, 2016 · Latest Apr 30, 2018
Typical ice-in
Dec 1
Earliest Nov 13, 2018 · Latest Dec 19, 2015
Most recent ice-out
Apr 14
2022
15 observations · Minnesota PCA ice records
EPA Impairment Status
Caroline 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: Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN86-0281-00 · Official waterbody report
Nearby Lakes in Wright County
Frequently asked questions about Caroline Lake
Where is Caroline Lake?
- Caroline Lake is a lake in Wright County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Caroline Lake?
- Caroline Lake in Wright County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3.5 ft visibility. Phosphorus: 53 µg/L. Chlorophyll-a (algae): 31.6 µg/L. Maximum depth: 45 ft. Surface area: 137.15 acres.
Is Caroline Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Caroline Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Caroline Lake?
- Caroline Lake typically sits around 61°F at the surface in September, from 354 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Caroline Lake?
- Caroline Lake has a maximum depth of 45 feet and an average depth of 15 feet. The lake covers 137.15 acres.
What fish are in Caroline Lake?
- Fish species found in Caroline Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, channel catfish, common carp, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, tullibee (cisco), walleye, white sucker, yellow bullhead, yellow perch. Caroline Lake is located in Wright County, Minnesota.
What did the DNR fisheries survey find at Caroline Lake?
- Minnesota DNR's Standard Survey on July 1, 2019 caught 1.83 walleye per gill net at Caroline Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Caroline Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
When does Caroline Lake thaw?
- Caroline Lake typically has ice-out around Apr 11. Ice typically forms around Dec 1. The open water season is approximately 234 days.
Can I fish at Caroline Lake?
- Public access to Caroline Lake is listed as no on the lake record, so confirm before you make the trip. 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 Caroline Lake across LakeQuality
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Where this data comes from
140 measurements from 2 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 Water
MNPCA140 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (2)
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
Ice data from Minnesota DNR Climate