Lake Wilhelm
Lake Wilhelm in Mercer County, Pennsylvania is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 1567 acres.
- Area
- 1,567 acres
- Public access
- Yes
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Why Lake Wilhelm has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Lake Wilhelm, no water-quality sampling on record for this lake.
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by PA DEP and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Lake Wilhelm is a 1,567-acre lake in Mercer County, Pennsylvania. Limited fish-species data available. Public access is available with 4 public boat landings.
Source: EPA Water Quality Portal sampling records, PA DEP, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Lake Wilhelm water quality
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Swimming Safety
Not ratedElevated nutrients
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Lake Wilhelm
These readings exist but are not enough for an A–F grade — see why.
No clarity data. Trophic State Index: undefined.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) |
Where to stay near Lake Wilhelm
Compare lakeside cabins, hotels, and vacation rentals near Lake Wilhelm in Mercer County, Pennsylvania — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Lake Wilhelm
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 1,567 acres |
| Public Access | Yes |
No bathymetric survey has been published for Lake Wilhelm, so its depth is not documented here.
Recreation & Access
- Lake Wilhelm #4Public
- Lake Wilhelm #2Public
- Lake Wilhelm MarinaPublic
- Lake Wilhelm #3Public
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Lake Wilhelm
Nearby Lakes in Mercer County
Frequently asked questions about Lake Wilhelm
Where is Lake Wilhelm?
- Lake Wilhelm is a lake in Mercer County, Pennsylvania. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Lake Wilhelm?
- Lake Wilhelm in Mercer County, Pennsylvania is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 1567 acres.
Is Lake Wilhelm safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lake Wilhelm is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Are there boat ramps on Lake Wilhelm?
- Lake Wilhelm has 4 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Lake Wilhelm #4, Lake Wilhelm #2, Lake Wilhelm Marina, Lake Wilhelm #3. Public access is listed as yes.
Explore Lake Wilhelm across LakeQuality
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Where this data comes from
Measurements for Lake Wilhelm come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Named boat-access points from the USGS National Boat Ramps inventory