Little Sand Lake
Forest County, WisconsinOligotrophic
On the LakeGrade rubric, Little Sand Lake pulls an A: clarity at 26.2 ft and 16 µg/L of phosphorus put it in the top bracket for Wisconsin. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.
The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. 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 237 acres, Little Sand Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Little Sand Lake ranks 5 of 35 in Forest County, putting it in the upper tier of locally monitored lakes.
No invasive species are currently listed at Little Sand Lake — the lake remains off the Wisconsin infested-waters roster. Walleye are documented at Little Sand Lake, one of 4 fish species on record for the lake. A documented public access point at Little Sand Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. 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 2022-09-21. 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 26.2 ft down. Phosphorus level: 15.9 µg/L. Trophic State Index: 37.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 26.2 ft | A |
| Phosphorus | 15.9 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 37 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 20 ft |
| Surface Area | 237 acres |
| Public Access | Yes |
Fish Species
Click a species to see all Wisconsin and Minnesota lakes where it is found.
→ Best fishing times for Little Sand Lake (14-day solunar calendar)
→ Is it safe to eat fish from Little Sand Lake? (mercury & PFAS guide)
→ Little Sand Lake fishing regulations (limits, seasons, special rules)
Water Quality Trend: ↓ Declining
Based on 2 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Phosphorus | ↓ Declining | +1.5 µg/L/yr | 2 |
Recreation & Access
Location
County Ranking
Ranked #5 of 35 lakes in Forest County
Nearby Lakes in Forest County
More Wisconsin Lake Rankings
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
Oligotrophic Lakes in Wisconsin
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. 1 station on file (most recent sample 2022).
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: 2022-09-21
Monitoring stations: 1