What is the water quality grade for Newton Lake?

Newton Lake in Jasper County, Wisconsin received a water quality grade of D (Poor). Water clarity: 1.7 ft visibility. Phosphorus: 82.5 µg/L.

Is Newton Lake safe to swim in?

Swimming not recommended, poor water quality with high algae risk. Newton Lake has an overall water quality grade of D. Always check local health department advisories before swimming.

Newton Lake

Jasper County, WisconsinEutrophic

Newton Lake is a productive, nutrient-rich eutrophic lake in Jasper County, IL. Water quality is graded D based on 2 sampling years through 2022.

Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2022-10-20. 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 1.7 ft of visibility. Phosphorus level: 82.5 µg/L. Trophic State Index: 69.

Metric	Value	Grade
Water Clarity (Secchi Depth)	1.7 ft	F
Phosphorus	82.5 µg/L	D
Chlorophyll-a (Algae)	No data
Trophic State Index (TSI)	69	Eutrophic

High nutrients, frequent algae, reduced clarity

Location

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County Ranking

Ranked #1 of 1 lakes in Jasper County

Cleaner Lakes Within 30 Miles

Newton Lake holds Grade D. 2 nearby lakes hold higher grades.

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Other Grade D Lakes in Wisconsin

Lake Opeka

Cook County · Clarity: 4 ft

Consumers Quarry Lake

Cook County · Clarity: 6.5 ft

Lake Arlington

Cook County · Clarity: 4.5 ft

Great Lakes Quarries East

Cook County · Clarity: 4.5 ft

Flatfoot Lake

Cook County · Clarity: 6 ft

Papoose Lake

Cook County · Clarity: 5 ft

Eutrophic Lakes in Wisconsin

Lake Opeka Consumers Quarry Lake Lake Charlemagne Lake Arlington

Reservoir Info (USACE NID)

Newton Lake is a man-made reservoir impounded by the Newton Station Ash Pond, built primarily for other on the NEWTON LAKE, 22 ft tall and 2,400 ft long.

Normal storage: 0 ac-ft
Hazard class: Significant

Source: USACE National Inventory of Dams, NID ID IL50719 · Operator website · Matched by proximity (0.8 km)

EPA Impairment Status

Newton Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).

Causes of impairment

MercuryNutrients (phosphorus, nitrogen)

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

Source: EPA ATTAINS assessment unit IL_RCR · Official waterbody report

Data Sources

Water quality data from the EPA Water Quality Portal

Impairment status from EPA ATTAINS 303(d) database

Grading methodology based on Metropolitan Council standards

Most recent sample: 2022-10-20

Monitoring stations: 4