Lake Mattawa
Lake Mattawa in Franklin County, Massachusetts is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 118 acres.
- Area
- 118 acres
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Why Lake Mattawa 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 Mattawa, 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 MassDEP and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Lake Mattawa is a 118-acre lake in Franklin County, Massachusetts.
Source: EPA Water Quality Portal sampling records, MassDEP, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Lake Mattawa 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 Mattawa
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 Mattawa
Compare lakeside cabins, hotels, and vacation rentals near Lake Mattawa in Franklin County, Massachusetts — 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 Mattawa
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 118 acres |
No bathymetric survey has been published for Lake Mattawa, so its depth is not documented here.
Fishing Lake Mattawa
Nearby Lakes in Franklin County
Frequently asked questions about Lake Mattawa
Where is Lake Mattawa?
- Lake Mattawa is a lake in Franklin County, Massachusetts. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Lake Mattawa?
- Lake Mattawa in Franklin County, Massachusetts is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 118 acres.
Is Lake Mattawa safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lake Mattawa 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 Mattawa come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.