Tulaby Lake
Mahnomen County, Minnesota832 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Tulaby Lake. Here is what has been measured.
- Eutrophic
- 43 ft max depth
- Public access
Tulaby Lake in Mahnomen County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7.8 ft visibility. Phosphorus: 23 µg/L. Chlorophyll-a (algae): 10.2 µg/L. Maximum depth: 43 ft. Surface area: 832.07 acres.
Minnesota DNR's Targeted Survey on July 18, 2023 caught 0.75 walleye per trap net at Tulaby Lake. Length samples in the latest survey that recorded them ran 7–28 inches. DNR survey details →
Free interactive depth-contour map of Tulaby Lake, reaching a maximum surveyed depth of 40 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Minnesota DNR.
Tulaby Lake is a 832-acre productive, nutrient-rich eutrophic lake in Mahnomen County, Minnesota with a maximum depth of 43 feet. Overall water quality is improving over recent sampling years. The lake supports 16 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 11 other monitored lakes in Mahnomen County, Tulaby Lake ranks #8 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-02. Methodology: how these readings are compared.
Tulaby Lake covers about 830 acres in Mahnomen County. It has one public boat landing. The median ice-out date is April 19, which is when the open-water season begins. Vrbo is where to look for cabins and lake homes around Tulaby Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Tulaby Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing16 species recorded
- Ice seasonIce-out around Apr 19
- Deep water43 ft surveyed max depth
Swimming conditions
Readings onlyModerate 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 Tulaby 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 Tulaby Lake
These are the measurements Minnesota PCA publishes for Tulaby 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 7.8 ft. Phosphorus 23 µg/L. Chlorophyll-a 10.2 µg/L. TSI 50.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 7.8ft | 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) | 10.2µg/L | Fair GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 50 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Tulaby Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Tulaby Lake typically sits around 64°F at the surface in October. Summer average is about 72°F. Usually warmest in Jul (about 75°F) and coldest in May (about 58°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (58°F) to its warmest (75°F).
Typical surface water temperature by month, from 180 field readings (2011–2025) via the EPA Water Quality Portal. See the full Tulaby Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Tulaby Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was high (159,956 cells/mL) on November 22, 2025.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Minnesota DNR's Targeted Survey on July 18, 2023 caught 0.75 walleye per trap net at Tulaby Lake. Length samples in the latest survey that recorded them ran 7–28 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Tulaby 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
14 surveys on file from MN DNR Fisheries. Most recent: 2025-08-07 (Targeted Survey).
14 surveys on file · most recent 2025-08-07 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Yellow Perch | 70.44 | 4–7 in 2023-07-18 | 0.14 lb |
| Bluegill | 12.71 | 3–9 in 2023-07-18 | 0.29 lb |
| Walleye | 8.60 | 7–28 in 2023-07-18 | 1.77 lb |
| Bluntnose Minnow | 8.24 |
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.
Yellow Perch
Bluegill
Walleye
From the 2025-08-07 survey
Coldwater habitat is needed by certain fish species such as Cisco, particularly during summer stratification. One coldwater habitat measure, the temperature at which dissolved oxygen decreases to 3.0 mg/L (i.e., TDO3), can be used to indicate whether coldwater habitat conditions support Cisco. Water quality data were…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Tulaby Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — TulabyFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Tulaby (1944)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — TulabyFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — TulabyPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
43 ft
Surface area
832 acres
Shoreline
5.8 mi
Littoral zone
34%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
3 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,526 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Tulaby 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 Tulaby Lake
Compare lakeside cabins, hotels, and vacation rentals near Tulaby Lake in Mahnomen 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 Tulaby 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 →
Follow Tulaby Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Tulaby Lake
Water Quality Trend: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving6 years
Phosphorus
Improving-1.57 µg/L/yr6 years
Chlorophyll-a
Improving-0.71 µg/L/yr6 years
Ice season
Typical ice-out
Apr 19
Earliest Mar 24, 2012 · Latest May 13, 2013
Typical ice-in
Nov 23
Earliest Nov 4, 1991 · Latest Dec 16, 1999
Most recent ice-out
Apr 5
2024
64 observations · Minnesota PCA ice records
Nearby Lakes in Mahnomen County
Frequently asked questions about Tulaby Lake
Where is Tulaby Lake?
- Tulaby Lake is a lake in Mahnomen County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Tulaby Lake?
- Tulaby Lake in Mahnomen County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 7.8 ft visibility. Phosphorus: 23 µg/L. Chlorophyll-a (algae): 10.2 µg/L. Maximum depth: 43 ft. Surface area: 832.07 acres.
Is Tulaby 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 Tulaby Lake?
- Tulaby Lake typically sits around 64°F at the surface in October, from 180 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Tulaby Lake?
- Tulaby Lake has a maximum depth of 43 feet. The lake covers 832.07 acres.
What fish are in Tulaby Lake?
- Fish species found in Tulaby Lake include black bullhead, black crappie, bluegill, brown bullhead, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, smallmouth bass, tullibee (cisco), walleye, white sucker, yellow bullhead, yellow perch. Tulaby Lake is located in Mahnomen County, Minnesota.
What did the DNR fisheries survey find at Tulaby Lake?
- Minnesota DNR's Targeted Survey on July 18, 2023 caught 0.75 walleye per trap net at Tulaby Lake. Length samples in the latest survey that recorded them ran 7–28 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Tulaby 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 Tulaby Lake thaw?
- Tulaby Lake typically has ice-out around Apr 19. Ice typically forms around Nov 23. The open water season is approximately 218 days.
Does Tulaby Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Tulaby Lake (clouds, ice, or an off-season gap). The most recent reading was high (159,956 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Tulaby Lake?
- Tulaby Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Tulaby Lake. Public access is listed as yes.
Can I fish at Tulaby Lake?
- Tulaby 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 Tulaby 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 Mahnomen County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Lakes in the Red River of the North Watershed, ranked by water quality
Minnesota's cleanest lakes, ranked on agency measurements
More lakes in Minnesota
State Parks Near Tulaby Lake
Other Lakes in Minnesota
Eutrophic Lakes in Minnesota
Compare Tulaby Lake With Nearby Lakes
Where this data comes from
248 measurements from 3 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
MNPCA209 samples · 2020–2025 - Minnesota Chippewa Tribe, Minnesota (White Earth Band) (Tribal)
WEARTH_WQX39 samples · 2023
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- Turbidity by Nephelometry
Monitoring station identifiers (3)
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
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate