What is the water quality grade for Gascoyne Lake?

Gascoyne Lake in Bowman County, Wisconsin received a water quality grade of D (Poor). Water clarity: 1.3 ft visibility. Chlorophyll-a (algae): 15.3 µg/L.

Is Gascoyne Lake safe to swim in?

Swimming not recommended, poor water quality with high algae risk. Gascoyne Lake has an overall water quality grade of D. Algae concentration (chlorophyll-a) is 15.3 µg/L. Always check local health department advisories before swimming.

Gascoyne Lake

Bowman County, WisconsinEutrophic

Gascoyne Lake is a 0-acre productive, nutrient-rich eutrophic lake in Bowman County, ND. Water quality is graded D based on 2 sampling years through 2023. Compared to the 3 other monitored lakes in Bowman County, Gascoyne Lake ranks #4 for water quality.

Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2023-10-10. Grade methodology: LakeGrade methodology.

Swimming Safety

Swimming not recommended, poor water quality with high algae risk

Water Quality Grade: D, Poor

Very murky, less than 1.3 ft of visibility. Chlorophyll-a: 15.3 µg/L. Trophic State Index: 65.

Metric	Value	Grade
Water Clarity (Secchi Depth)	1.3 ft	F
Phosphorus	No data
Chlorophyll-a (Algae)	15.3 µg/L	C
Trophic State Index (TSI)	65	Eutrophic

High nutrients, frequent algae, reduced clarity

Location

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County Ranking

Ranked #4 of 4 lakes in Bowman County

Cleaner Lakes Within 30 Miles

Gascoyne Lake holds Grade D. 4 nearby lakes hold higher grades.

See full comparison →

Nearby Lakes in Bowman County

Bowman-Haley Dam Lake

Indian Creek Dam Lake

Hettinger County

More Wisconsin Lake Rankings

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Top 25 by overall water quality score

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Grade A/B + low algae filter

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Panfish-rich, public access

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Other Grade D Lakes in Wisconsin

Dry Lake

Ramsey County · Clarity: 2.8 ft

Lake Alice

Ramsey County · Clarity: 3.1 ft

E. A. Patterson Lake

Stark County · Clarity: 5.3 ft

Lake Irvine

Ramsey County · Clarity: 2.9 ft

Lake Laretta

Nelson County · Clarity: 3.8 ft

Sweetwater Lake

Ramsey County · Clarity: 2.9 ft

Eutrophic Lakes in Wisconsin

Lake Alice J. Clark Salyer Pool 357 E. A. Patterson Lake Lake Irvine

Reservoir Info (USACE NID)

Gascoyne Lake is a man-made reservoir impounded by the Gascoyne Lake Dam (completed 1934), built primarily for recreation on the Buffalo Creek-TR; earth-type dam, 8 ft tall and 1,265 ft long.

Surface area: 0 ac
Normal storage: 1,300 ac-ft
Max storage: 1,691 ac-ft
Drainage area: 4 sq mi
Hazard class: Low
Owner: Bowman County WRB

Source: USACE National Inventory of Dams, NID ID ND00375 · Operator website

Data Sources

Water quality data from the EPA Water Quality Portal

Grading methodology based on Metropolitan Council standards

Most recent sample: 2023-10-10

Monitoring stations: 1