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LakeQuality

Watap Lake

NR
Not yet rated
9 ft clear · Mesotrophic · 1,993 acres
Limited DataMesotrophic

Watap Lake in Cook County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 9 ft visibility. Maximum depth: 210 ft. Surface area: 1992.66 acres.

Clarity
9 ft
Max depth
210 ft
Area
1,993 acres
Public access
No

Next lake in Cook County

AClearwater Lake29 ft clear · Cook CountyView →
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Why Watap Lake has no grade

We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Watap Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).

Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.

Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.

Watap Lake is a 1,993-acre lake in Cook County, Minnesota with a maximum depth of 210 feet. The lake supports 1 documented fish species including lake trout. No public access — the lake is private or restricted.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-07-30. Grade methodology: LakeGrade methodology.

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Swimming Safety

Not rated

Limited data

Not rated for swimming — there is not enough monitoring data to judge this lake

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Water quality measurements for Watap Lake

These readings exist but do not meet the evidence bar for an A–F grade — see why.

Moderate clarity, visible to about 9 ft. Trophic State Index: 45.

MetricValueGrade
Water Clarity (Secchi Depth)9 ftNot graded
PhosphorusNo recent samples
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)45Mesotrophic

Moderate nutrients, good water quality

Where to stay near Watap Lake

Compare lakeside cabins, hotels, and vacation rentals near Watap Lake in Cook 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 Watap 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 Depth210 ft
Surface Area1,993 acres
Shoreline Length35.7 mi
Littoral Zone25%
Public AccessNo

Lake Size & Watershed

Watershed (drainage) area
3 sq mi
Elevation
1,660 ft

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

Fish Species

Click a species to see every graded lake where it is documented.

Fishing Watap Lake

DNR Fisheries Survey Summary

8 surveys on file from MN DNR Fisheries. Most recent: 2025-08-12 (Targeted Survey).

Top Species by Catch Rate

SpeciesAvg CPUEAvg Weight
Lake Trout9.791.36 lb
White Sucker6.861 lb
Spottail Shiner0.92
Smallmouth Bass0.720.5 lb
SCU0.170.03 lb
Fathead Minnow0.08

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

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.

Lake Trout

73 fish · 1040 in · 2011-09-19
24120trophy 3010121416182022242628303234363840

White Sucker

34 fish · 1220 in · 2011-09-19
1050121314151617181920

Smallmouth Bass

8 fish · 1011 in · 2011-09-19
5301011

SCU

1 fish · 44 in · 2011-09-19
104

From the 2025-08-12 survey

Temperature and dissolved oxygen (DO) measurements were collected from the deepest basin in Mountain Lake on August 12th, 2025, to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Lake Trout, the most sensitive coldwater species present in this lake. During the…

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 Watap Lake. 1 report on file.

These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).

EPA Impairment Status

Watap Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).

Causes of impairment

Mercury

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit MN16-0139-00 · Official waterbody report · Matched by proximity (2.68 km)

Graded lakes near Watap Lake

Watap Lake has no grade, but these lakes within a short drive do.

Nearby Lakes in Cook County

Frequently asked questions about Watap Lake

What is the water quality grade for Watap Lake?

Watap Lake in Cook County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 9 ft visibility. Maximum depth: 210 ft. Surface area: 1992.66 acres.

Is Watap Lake safe to swim in?

Not rated for swimming — there is not enough monitoring data to judge this lake. Watap Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.

How deep is Watap Lake?

Watap Lake has a maximum depth of 210 feet. The lake covers 1992.66 acres.

What fish are in Watap Lake?

Fish species found in Watap Lake include lake trout. Watap Lake is located in Cook County, Minnesota.

Where this data comes from

1 measurement from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Minnesota Pollution Control Agency - Ambient Surface WaterMNPCA1 sample · 2024

Analytical methods

  • Field measurement/observation, generic method
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

Impairment status from EPA ATTAINS 303(d) database

Lake size & watershed from HydroLAKES (HydroSHEDS)

Lake details from Minnesota DNR LakeFinder