Lake Mahopac
Lake Mahopac in Putnam County, New York is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 598 acres.
- Area
- 598 acres
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Why Lake Mahopac 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 Mahopac, 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 NYSDEC and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Lake Mahopac is a 598-acre lake in Putnam County, New York.
Source: EPA Water Quality Portal sampling records, NYSDEC, last sampled recent years. Grade methodology: LakeQuality methodology.
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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 Mahopac
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 Mahopac
Compare lakeside cabins, hotels, and vacation rentals near Lake Mahopac in Putnam County, New York — 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 Mahopac
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 598 acres |
No bathymetric survey has been published for Lake Mahopac, so its depth is not documented here.
Fishing Lake Mahopac
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Frequently asked questions about Lake Mahopac
Where is Lake Mahopac?
- Lake Mahopac is a lake in Putnam County, New York. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Lake Mahopac?
- Lake Mahopac in Putnam County, New York is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 598 acres.
Is Lake Mahopac safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lake Mahopac is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
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Where this data comes from
Measurements for Lake Mahopac come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.