Lake Helen
Portage County, WisconsinLimited DataMesotrophic
On the LakeGrade rubric, Lake Helen pulls an A: clarity readings still being added and 16 µg/L of phosphorus put it in the top bracket for Wisconsin. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.
The lake sits in the mesotrophic zone — the band where most well-managed Wisconsin lakes fall. The lake bottoms out at 20 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 89 acres, Lake Helen sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Within Portage County's 29 graded lakes, Lake Helen ranks 19 — below the local median, though not at the bottom.
Zebra mussel presence at Lake Helen means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. Bass fishing is part of the appeal: the species list runs to 3, anchored by largemouth and/or smallmouth bass. 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 2021-09-13. Grade methodology: LakeGrade methodology.
Swimming Safety
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A, Excellent
No clarity data. Phosphorus level: 16.1 µg/L. Trophic State Index: 44.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No data | |
| Phosphorus | 16.1 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 44 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 20 ft |
| Surface Area | 89 acres |
| Public Access | Yes |
Fish Species
Click a species to see all Wisconsin and Minnesota lakes where it is found.
→ Best fishing times for Lake Helen (14-day solunar calendar)
→ Is it safe to eat fish from Lake Helen? (mercury & PFAS guide)
→ Lake Helen fishing regulations (limits, seasons, special rules)
Invasive Species
Water Quality Trend: → Stable
Based on 7 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.416 m/yr | 7 |
| Phosphorus | ↑ Improving | -0.64 µg/L/yr | 6 |
Recreation & Access
Location
County Ranking
Ranked #19 of 29 lakes in Portage County
Nearby Lakes in Portage County
More Wisconsin Lake Rankings
State Parks Near Lake Helen
Other Grade A Lakes in Wisconsin
Waukesha County · Clarity: 14.6 ft
Waukesha County · Clarity: 13.8 ft
Walworth County · Clarity: 19 ft
Washington County · Clarity: 12 ft
Kenosha County · Clarity: 10.1 ft
Washington County · Clarity: 12.5 ft
Mesotrophic Lakes in Wisconsin
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 1997. 7 stations on file (most recent sample 2025).
Fish Species (DNR-rated)
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Fish and recreation data from Wisconsin DNR Lakes
Most recent sample: 2021-09-13
Monitoring stations: 1