What is the water quality grade for Fawn Lake?

Fawn Lake in Franklin County, Wisconsin received a water quality grade of C (Fair). Water clarity: 3.6 ft visibility. Phosphorus: 30 µg/L. Chlorophyll-a (algae): 10.8 µg/L. Surface area: 25 acres.

Is Fawn Lake safe to swim in?

Generally safe for swimming, moderate water quality. Fawn Lake has an overall water quality grade of C. Algae concentration (chlorophyll-a) is 10.8 µg/L. Always check local health department advisories before swimming.

Fawn Lake

Franklin County, WisconsinEutrophic

Fawn Lake is a 25-acre productive, nutrient-rich eutrophic lake in Franklin County, MO. Water quality is graded C based on 3 sampling years through 2024. Compared to the 4 other monitored lakes in Franklin County, Fawn Lake ranks #3 for water quality.

Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2024-09-20. Grade methodology: LakeGrade methodology.

Swimming Safety

Generally safe for swimming, moderate water quality

Water Quality Grade: C, Fair

Murky, only visible to about 3.6 ft. Phosphorus level: 30 µg/L. Chlorophyll-a: 10.8 µg/L. Trophic State Index: 55.

Metric	Value	Grade
Water Clarity (Secchi Depth)	3.6 ft	D
Phosphorus	30 µg/L	C
Chlorophyll-a (Algae)	10.8 µg/L	C
Trophic State Index (TSI)	55	Eutrophic

High nutrients, frequent algae, reduced clarity

Lake Details

Characteristic	Value
Surface Area	25 acres

Location

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County Ranking

Ranked #3 of 5 lakes in Franklin County

Cleaner Lakes Within 30 Miles

Fawn Lake holds Grade C. 3 nearby lakes hold higher grades.

See full comparison →

Nearby Lakes in Franklin County

More Wisconsin Lake Rankings

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Other Grade C Lakes in Wisconsin

Aspen Lake Along Southern Arm

Warren County · Clarity: 3.8 ft

Mark Twain Lake by Hwy J

Ralls County · Clarity: 3.7 ft

Red Fox Lake

Warren County · Clarity: 3.3 ft

Waukomis Lake

Platte County · Clarity: 4.7 ft

Table Rock L. Nr. Greens Hollow Lake

Barry County · Clarity: 5 ft

Little Prairie Lake by Dam

Phelps County · Clarity: 4.9 ft

Eutrophic Lakes in Wisconsin

Aspen Lake Along Southern Arm Boathouse Lake Hunnewell Lake Long Branch Lk. Lake

Reservoir Info (USACE NID)

Fawn Lake is a man-made reservoir impounded by the Fawn Lake Dam (completed 1969), built primarily for recreation on the TR TO ST JOHNS CR; earth-type dam, 43 ft tall and 650 ft long.

Surface area: 25 ac
Normal storage: 207 ac-ft
Max storage: 400 ac-ft
Drainage area: 0.91 sq mi
Hazard class: Significant
Owner: FAWN LAKE ESTATES

Source: USACE National Inventory of Dams, NID ID MO31253 · Operator website

Data Sources

Water quality data from the EPA Water Quality Portal

Grading methodology based on Metropolitan Council standards

Most recent sample: 2024-09-20

Monitoring stations: 1