D

Jefferson Lake

St. Louis city County, WisconsinEutrophic

Jefferson Lake is a productive, nutrient-rich eutrophic lake in St. Louis city County, MO. Water quality is graded D based on 2 sampling years through 2020. Compared to the 4 other monitored lakes in St. Louis city County, Jefferson Lake ranks #5 for water quality.

Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2020-08-24. Grade methodology: LakeGrade methodology.

Swimming Safety

Swimming not recommended, poor water quality with high algae risk

Water Quality Grade: D, Poor

No clarity data. Phosphorus level: 70 µg/L. Chlorophyll-a: 55.2 µg/L. Trophic State Index: 68.

Metric	Value	Grade
Water Clarity (Secchi Depth)	No data
Phosphorus	70 µg/L	D
Chlorophyll-a (Algae)	55.2 µg/L	F
Trophic State Index (TSI)	68	Eutrophic

High nutrients, frequent algae, reduced clarity

Location

Loading map…

County Ranking

Ranked #5 of 5 lakes in St. Louis city County

Cleaner Lakes Within 30 Miles

Jefferson Lake holds Grade D. 5 nearby lakes hold higher grades.

See full comparison →

Nearby Lakes in St. Louis city County

St. Louis city County

O'Fallon Park Lake

St. Louis city County

Lafayette Park Lake

St. Louis city County

Forest Park Pond

St. Louis city 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 D Lakes in Wisconsin

Shelby County · Clarity: 3.2 ft

Long Branch Lk. Lake

Macon County · Clarity: 1.8 ft

Harrison County Lake Intake

Harrison County · Clarity: 1.7 ft

Table Rock L. Bl. Hwy. 173 Lake

Stone County · Clarity: 2.3 ft

Henry Sever Lake

Knox County · Clarity: 2.1 ft

W Arm Loto Lake

Camden County · Clarity: 2.7 ft

Eutrophic Lakes in Wisconsin

Aspen Lake Along Southern Arm Hunnewell Lake Long Branch Lk. Lake Creve Coeur Lake

Data Sources

Water quality data from the EPA Water Quality Portal

Grading methodology based on Metropolitan Council standards

Most recent sample: 2020-08-24

Monitoring stations: 1