Lewiston Lake
Lewiston Lake in Trinity County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 674 acres.
- Area
- 674 acres
- Public access
- Yes
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Why Lewiston Lake 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 Lewiston Lake, 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 your state environmental agency and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Lewiston Lake is a 674-acre lake in Trinity County, California. Limited fish-species data available. Public access is available with 2 public boat landings.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Lewiston Lake 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 Lewiston Lake
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 Lewiston Lake
Compare lakeside cabins, hotels, and vacation rentals near Lewiston Lake in Trinity County, California — 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 Lewiston Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 674 acres |
| Public Access | Yes |
No bathymetric survey has been published for Lewiston Lake, so its depth is not documented here.
Recreation & Access
- Trinity Lake National Recreation Area (Pine Cove )Public
- Pine Cove MarinaPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Lewiston Lake
Nearby Lakes in Trinity County
Frequently asked questions about Lewiston Lake
Where is Lewiston Lake?
- Lewiston Lake is a lake in Trinity County, California. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Lewiston Lake?
- Lewiston Lake in Trinity County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 674 acres.
Is Lewiston Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lewiston Lake 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 Lewiston Lake?
- Lewiston Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Trinity Lake National Recreation Area (Pine Cove ), Pine Cove Marina. Public access is listed as yes.
Explore Lewiston Lake across LakeQuality
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Where this data comes from
Measurements for Lewiston Lake 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