Upper Kelly Lake
Waukesha County, WisconsinLimited DataEutrophic
Upper Kelly Lake earns an F: phosphorus readings still being added and clarity at 2.0 ft signal heavy nutrient loading from the surrounding watershed. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.
At a TSI of 67, Upper Kelly Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. A maximum depth of 31 ft puts Upper Kelly Lake in the middle of Wisconsin's depth distribution. At 13 acres, Upper Kelly Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Upper Kelly Lake ranks 44 of 45 in Waukesha County — at the lower end of the locally monitored distribution.
Eurasian watermilfoil is established at Upper Kelly Lake, which can dampen recreational access and pressure the native plant community. The fishery is bass-led, with 2 documented species across the lake's records. Public access is available — the lake is on the Wisconsin DNR public-access list. 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 2024-09-09. Grade methodology: LakeGrade methodology.
Watch Upper Kelly Lake water quality
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Swimming Safety
Avoid swimming, very poor water quality, potential algae toxins
Water Quality Grade: F, Very Poor
Very murky, less than 2 ft of visibility. Trophic State Index: 67.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 67 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 31 ft |
| Surface Area | 13 acres |
| Public Access | Yes |
Fish Species
Click a species to see every graded lake where it is documented.
→ Best fishing times for Upper Kelly Lake (14-day solunar calendar)
→ Is it safe to eat fish from Upper Kelly Lake? (mercury & PFAS guide)
→ Upper Kelly Lake fishing regulations (limits, seasons, special rules)
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
Water Quality Trend: ↑ Improving
Based on 3 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.188 m/yr | 2 |
Recreation & Access
Location
County Ranking
Ranked #44 of 45 lakes in Waukesha County
Cleaner Lakes Within 30 Miles
Upper Kelly Lake holds Grade F. 3 nearby lakes hold higher grades.
Nearby Lakes in Waukesha County
More Wisconsin Lake Rankings
State Parks Near Upper Kelly Lake
Other Grade F Lakes in Wisconsin
Eutrophic Lakes in Wisconsin
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. 1 station on file (most recent sample 2024).
Fish Species (DNR-rated)
EPA Impairment Status
Upper Kelly Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5R).
Causes of impairment
Source: EPA ATTAINS assessment unit WI10008146 · 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
Fish and recreation data from Wisconsin DNR Lakes
Public boat-access points from the USGS National Boat Ramps inventory
Most recent sample: 2024-09-09
Monitoring stations: 1
Where to stay near Upper Kelly Lake
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