What is the water quality grade for Milan Lake North?

Milan Lake North in Sullivan County, Wisconsin received a water quality grade of B (Good). Phosphorus: 51.8 µg/L. Chlorophyll-a (algae): 7.8 µg/L. Surface area: 15 acres.

Is Milan Lake North safe to swim in?

Good for swimming, clear water with low algae levels. Milan Lake North has an overall water quality grade of B. Algae concentration (chlorophyll-a) is 7.8 µg/L. Always check local health department advisories before swimming.

Milan Lake North

Sullivan County, WisconsinEutrophic

Milan Lake North is a 15-acre productive, nutrient-rich eutrophic lake in Sullivan County, MO. Water quality is graded B based on 2 sampling years through 2024. Compared to the 1 other monitored lakes in Sullivan County, Milan Lake North ranks #1 for water quality.

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

Swimming Safety

Good for swimming, clear water with low algae levels

Water Quality Grade: B, Good

No clarity data. Phosphorus level: 51.8 µg/L. Chlorophyll-a: 7.8 µg/L. Trophic State Index: 56.

Metric	Value	Grade
Water Clarity (Secchi Depth)	No data
Phosphorus	51.8 µg/L	C
Chlorophyll-a (Algae)	7.8 µg/L	B
Trophic State Index (TSI)	56	Eutrophic

High nutrients, frequent algae, reduced clarity

Lake Details

Characteristic	Value
Surface Area	15 acres

Location

Loading map…

County Ranking

Ranked #1 of 2 lakes in Sullivan County

Cleaner Lakes Within 30 Miles

Milan Lake North holds Grade B. 2 nearby lakes hold higher grades.

See full comparison →

Nearby Lakes in Sullivan County

Pershing State Park Lake

Linn County

Forest Lake

Adair County

Forest Lake Se Branch

Adair County

More Wisconsin Lake Rankings

Cleanest lakes in Wisconsin

Top 25 by overall water quality score

Best swimming lakes in Wisconsin

Grade A/B + low algae filter

Family fishing lakes in Wisconsin

Panfish-rich, public access

All Wisconsin lakes

Full state directory

Other Grade B Lakes in Wisconsin

Table Rock Lake

Taney County · Clarity: 10 ft

Whippoorwill Lake

Warren County · Clarity: 5 ft

Lake Taneycomo @ Rockaway Beach

Taney County · Clarity: 8.7 ft

Forest Lake

Adair County · Clarity: 4.1 ft

Fox Valley Lake

Clark County · Clarity: 8.5 ft

Sherwood Lake Nr. Dam

Warren County · Clarity: 5.9 ft

Eutrophic Lakes in Wisconsin

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

Reservoir Info (USACE NID)

Milan Lake North is a man-made reservoir impounded by the Milan Lake Dam-North (completed 1911), built primarily for recreation on the TR-LOCUST CREEK; earth-type dam, 30 ft tall.

Surface area: 15 ac
Normal storage: 125 ac-ft
Max storage: 241 ac-ft
Drainage area: 190 sq mi
Hazard class: Low
Owner: CITY OF MILAN

All listed purposes: Recreation;Water Supply.

Source: USACE National Inventory of Dams, NID ID MO10399 · Operator website

EPA Impairment Status

Milan Lake North is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).

Causes of impairment

Algal growth

Source: EPA ATTAINS assessment unit MO_7144.00 · 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: 2024-07-30

Monitoring stations: 1