Skip to main content
LakeQuality
C

Cedar Lake

Carlton County, MinnesotaEutrophic

Cedar Lake sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

At a TSI of 56, Cedar 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 the 33 graded lakes of Carlton County, Cedar Lake sits at rank 25, near the bottom of the county list.

No invasive species are currently listed at Cedar Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Cedar Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. The grade is supported by multiple sampling years from Minnesota PCA volunteers and partner agencies, giving the letter a reasonably stable foundation.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-07-02. Grade methodology: LakeGrade methodology.

Swimming Safety

Generally safe for swimming, moderate water quality

Water Quality Grade: C, Fair

Murky, only visible to about 4.3 ft. Phosphorus level: 40 µg/L. Chlorophyll-a: 10 µg/L. Trophic State Index: 56.

MetricValueGrade
Water Clarity (Secchi Depth)4.3 ftD
Phosphorus40 µg/LC
Chlorophyll-a (Algae)10 µg/LC
Trophic State Index (TSI)56Eutrophic

High nutrients, frequent algae, reduced clarity

Water Quality Trend: Improving

Based on 6 years of monitoring data (2020-2025).

MetricTrendChange/YearYears
Water Clarity Stable+0.25 m/yr5
Phosphorus Improving-20 µg/L/yr2
Chlorophyll-a Improving-0.9 µg/L/yr5

Location

Loading map…

County Ranking

Ranked #25 of 33 lakes in Carlton County

Nearby Lakes in Carlton County

Data Sources

Water quality data from the EPA Water Quality Portal

Grading methodology based on Metropolitan Council standards

Most recent sample: 2024-07-02

Monitoring stations: 1