Skip to main content
LakeQuality
C

Unnamed Lake

Polk County, WisconsinEutrophic

Unnamed Lake sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year. The lake's weakest score is on Secchi depth — the water looks more turbid than its phosphorus number alone would predict.

At a TSI of 51, Unnamed Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Within Polk County's 74 graded lakes, Unnamed Lake ranks 45 — below the local median, though not at the bottom.

Unnamed Lake has no invasive species recorded in Wisconsin state databases as of 2022, though prevention practices still apply at all access points. The state fisheries records do not list documented species for Unnamed Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.

Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2022-09-13. Grade methodology: LakeGrade methodology.

Watch Unnamed Lake water quality

Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.

Swimming Safety

Generally safe for swimming, moderate water quality

Water Quality Grade: C, Fair

Murky, only visible to about 5 ft. Phosphorus level: 22.4 µg/L. Trophic State Index: 51.

MetricValueGrade
Water Clarity (Secchi Depth)5 ftD
Phosphorus22.4 µg/LB
Chlorophyll-a (Algae)No data
Trophic State Index (TSI)51Eutrophic

High nutrients, frequent algae, reduced clarity

Water Quality Trend: Declining

Based on 2 years of monitoring data (2020-2025).

MetricTrendChange/YearYears
Water Clarity Declining-5.25 m/yr2
Phosphorus Declining+4.25 µg/L/yr2

Location

Loading map…

County Ranking

Ranked #45 of 74 lakes in Polk County

Cleaner Lakes Within 30 Miles

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

See full comparison →

Nearby Lakes in Polk County

Data Sources

Water quality data from the EPA Water Quality Portal

Grading methodology based on Metropolitan Council standards

Fish and recreation data from Wisconsin DNR Lakes

Most recent sample: 2022-09-13

Monitoring stations: 1

Where to stay near Unnamed Lake

Compare lakeside cabins, hotels, and vacation rentals near Unnamed Lake in Polk County, Wisconsin — live availability and prices for your trip.

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.