Lake Paho
Mercer County, WisconsinEutrophic
Lake Paho is a 269-acre productive, nutrient-rich eutrophic lake in Mercer County, MO. Water quality is graded D based on 3 sampling years through 2021. Compared to the 1 other monitored lakes in Mercer County, Lake Paho ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2021-09-01. 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 2.2 ft of visibility. Phosphorus level: 37 µg/L. Chlorophyll-a: 48.2 µg/L. Trophic State Index: 64.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.2 ft | F |
| Phosphorus | 37 µg/L | C |
| Chlorophyll-a (Algae) | 48.2 µg/L | F |
| Trophic State Index (TSI) | 64 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 269.1 acres |
Location
County Ranking
Ranked #2 of 2 lakes in Mercer County
Cleaner Lakes Within 30 Miles
Lake Paho holds Grade D. 2 nearby lakes hold higher grades.
- BLake MarieMercer County · 7.9 mi · Two grade letters higher (D → B)
- BNorth Bethany City ReservoirHarrison County · 20.8 mi · Two grade letters higher (D → B)
Nearby Lakes in Mercer County
More Wisconsin Lake Rankings
Other Grade D Lakes in Wisconsin
St. Louis city County · Clarity: 2.3 ft
Shelby County · Clarity: 3.2 ft
Macon County · Clarity: 1.8 ft
Harrison County · Clarity: 1.7 ft
Stone County · Clarity: 2.3 ft
Knox County · Clarity: 2.1 ft
Eutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Lake Paho is a man-made reservoir impounded by the Lake Paho Dam (completed 1951), built primarily for recreation on the WEST MUDDY CREEK; earth-type dam, 40 ft tall and 1,075 ft long.
- Surface area
- 269.1 ac
- Normal storage
- 3,477 ac-ft
- Max storage
- 5,884 ac-ft
- Drainage area
- 4.78 sq mi
- Hazard class
- High
- Owner
- MO DEPT OF CONSERVATION
Source: USACE National Inventory of Dams, NID ID MO10108 · Operator website
EPA Impairment Status
Lake Paho is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit MO_7132.00 · 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: 2021-09-01
Monitoring stations: 1