Lake Capri
St. Francois County, WisconsinOligotrophic
Lake Capri is a 112-acre cold, clear oligotrophic lake in St. Francois County, MO. Water quality is graded A based on 3 sampling years through 2025. Compared to the 3 other monitored lakes in St. Francois County, Lake Capri ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2025-07-29. Grade methodology: LakeGrade methodology.
Swimming Safety
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A, Excellent
Crystal clear, you can see 16.3 ft down. Phosphorus level: 5.7 µg/L. Chlorophyll-a: 0.9 µg/L. Trophic State Index: 32.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 16.3 ft | A |
| Phosphorus | 5.7 µg/L | A |
| Chlorophyll-a (Algae) | 0.9 µg/L | A |
| Trophic State Index (TSI) | 32 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 112 acres |
Location
County Ranking
Ranked #1 of 4 lakes in St. Francois County
Nearby Lakes in St. Francois County
More Wisconsin Lake Rankings
Other Grade A Lakes in Wisconsin
Jefferson County · Clarity: 12.9 ft
Washington County · Clarity: 11.1 ft
Warren County · Clarity: 12.6 ft
Taney County · Clarity: 13.3 ft
Taney County · Clarity: 12.6 ft
Iron County · Clarity: 13.1 ft
Oligotrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Lake Capri is a man-made reservoir impounded by the Lac Capri Dam (completed 1972), built primarily for recreation on the TR BIG RIVER; earth-type dam, 97 ft tall and 2,170 ft long.
- Surface area
- 112 ac
- Normal storage
- 2,828 ac-ft
- Max storage
- 3,541 ac-ft
- Drainage area
- 0.99 sq mi
- Hazard class
- High
- Owner
- TERRE DU LAC POA
Source: USACE National Inventory of Dams, NID ID MO30063 · Operator website · Matched by proximity (0.04 km)
EPA Impairment Status
Lake Capri 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_7297.00 · Official waterbody report · Matched by proximity (0.28 km)
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: 2025-07-29
Monitoring stations: 2