Upper Cullen Lake
Crow Wing County, Minnesota441 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Upper Cullen Lake. Here is what has been measured.
- Mesotrophic
- 40 ft max depth
- Public access
Upper Cullen Lake in Crow Wing County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 8.7 ft visibility. Phosphorus: 23 µg/L. Chlorophyll-a (algae): 6.8 µg/L. Maximum depth: 40 ft. Surface area: 441.47 acres.
Minnesota DNR's Targeted Survey on September 2, 2021 caught 1.00 largemouth bass per hour of electrofishing at Upper Cullen Lake. Length samples in the latest survey that recorded them ran 2–19 inches. DNR survey details →
Upper Cullen Lake is a 441-acre mesotrophic lake in Crow Wing County, Minnesota with a maximum depth of 40 feet. The lake supports 14 documented fish species including black crappie, bluegill, and bowfin (dogfish). Public access is available. Compared to the 84 other monitored lakes in Crow Wing County, Upper Cullen Lake ranks #56 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-20. Methodology: how these readings are compared.
Upper Cullen Lake covers about 440 acres in Crow Wing County. The median ice-out date is April 12, which is when the open-water season begins. Vrbo is where to look for cabins and lake homes around Upper Cullen Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Upper Cullen Lake is good for
From access and monitoring records, not editorial picks.
- Fishing14 species recorded
- Ice seasonIce-out around Apr 12
- Deep water40 ft surveyed max depth
Swimming conditions
Readings onlyLow algae
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. Check local advisories before you swim.
Whether Upper Cullen 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 Upper Cullen Lake
These are the measurements Minnesota PCA publishes for Upper Cullen Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 8.7 ft. Phosphorus 23 µg/L. Chlorophyll-a 6.8 µg/L. TSI 48.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 8.7ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 23µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 6.8µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 48 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Upper Cullen Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Upper Cullen Lake typically sits around 68°F at the surface in September. Summer average is about 74°F. Usually warmest in Jul (about 77°F) and coldest in May (about 61°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (61°F) to its warmest (77°F).
Typical surface water temperature by month, from 36 field readings (2016–2025) via the EPA Water Quality Portal. See the full Upper Cullen Lake water temperature breakdown →
Minnesota DNR's Targeted Survey on September 2, 2021 caught 1.00 largemouth bass per hour of electrofishing at Upper Cullen Lake. Length samples in the latest survey that recorded them ran 2–19 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Upper Cullen Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
10 surveys on file from MN DNR Fisheries. Most recent: 2021-09-02 (Targeted Survey).
10 surveys on file · most recent 2021-09-02 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluntnose Minnow | 23.16 | ||
| Bluegill | 17.08 | 2–8 in 2021-07-06 | 0.18 lb |
| Largemouth Bass | 11.37 | 2–19 in 2021-07-06 | 1.33 lb |
| Tullibee (Cisco) | 6.03 | 8–13 in 2015-07-06 | 0.76 lb |
| Northern Pike | 5.70 | 11–34 in 2021-07-06 | 1.78 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.
Bluegill
Largemouth Bass
Tullibee (Cisco)
Northern Pike
From the 2021-09-02 survey
Upper Cullen Lake is a 435 acre lake, with a maximum depth of 40', located 6 miles northeast of the town of Nisswa in Crow Wing County. Upper Cullen is located in the Crow Wing River watershed. A nearshore survey was conducted to assess the populations of both game and non-game fish species. Ten 100' long sampling…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Upper Cullen Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — Upper CullenFisheries Lake Survey · MN DNR LakeFinder
Lake Details
Max depth
40 ft
Surface area
441 acres
Shoreline
4.9 mi
Littoral zone
68%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
13 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,181 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Upper Cullen Lake
Compare lakeside cabins, hotels, and vacation rentals near Upper Cullen Lake in Crow Wing 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 Upper Cullen Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Fish Species
Click a species to see every lake where it is documented.
Fishing Upper Cullen Lake
- → Upper Cullen Lake fishing: DNR survey catch rates, species & stocking
- → Upper Cullen Lake fishing forecast & best times (species outlook + 14-day solunar calendar)
- → Upper Cullen Lake fishing regulations (limits, seasons, special rules)
- → Is it safe to eat fish from Upper Cullen Lake? (mercury & PFAS guide)
Water Quality Trend: Stable
Based on 6 years of monitoring (2020–2025).
Water clarity
Stable6 years
Phosphorus
Stable-0.16 µg/L/yr6 years
Chlorophyll-a
Stable-0.04 µg/L/yr6 years
Ice season
Typical ice-out
Apr 12
Earliest Mar 8, 2016 · Latest May 2, 2022
Typical ice-in
Nov 24
Earliest Nov 15, 2002 · Latest Dec 1, 2007
Most recent ice-out
Mar 29
2024
29 observations · Minnesota PCA ice records
Nearby Lakes in Crow Wing County
Frequently asked questions about Upper Cullen Lake
Where is Upper Cullen Lake?
- Upper Cullen Lake is a lake in Crow Wing County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Upper Cullen Lake?
- Upper Cullen Lake in Crow Wing County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 8.7 ft visibility. Phosphorus: 23 µg/L. Chlorophyll-a (algae): 6.8 µg/L. Maximum depth: 40 ft. Surface area: 441.47 acres.
Is Upper Cullen Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Upper Cullen Lake?
- Upper Cullen Lake typically sits around 68°F at the surface in September, from 36 EPA Water Quality Portal field readings (2016–2025). That is a typical value for the month, not a live reading.
How deep is Upper Cullen Lake?
- Upper Cullen Lake has a maximum depth of 40 feet. The lake covers 441.47 acres.
What fish are in Upper Cullen Lake?
- Fish species found in Upper Cullen Lake include black crappie, bluegill, bowfin (dogfish), brown bullhead, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, smallmouth bass, walleye, yellow bullhead, yellow perch. Upper Cullen Lake is located in Crow Wing County, Minnesota.
What did the DNR fisheries survey find at Upper Cullen Lake?
- Minnesota DNR's Targeted Survey on September 2, 2021 caught 1.00 largemouth bass per hour of electrofishing at Upper Cullen Lake. Length samples in the latest survey that recorded them ran 2–19 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Upper Cullen Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
When does Upper Cullen Lake thaw?
- Upper Cullen Lake typically has ice-out around Apr 12. Ice typically forms around Nov 24. The open water season is approximately 226 days.
Can I fish at Upper Cullen Lake?
- Public access to Upper Cullen Lake is listed as yes on the lake record. 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 Upper Cullen Lake across LakeQuality
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Species activity outlook by water temperature and season
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Where this data comes from
80 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
MNPCA80 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H 2 ~ Chlorophyll a-b-c Determination by spectrophotometer
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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Ice data from Minnesota DNR Climate