Pine Mountain Lake
Pine Mountain Lake in Tuolumne County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 18 ft visibility. Surface area: 200 acres.
- Clarity
- 18 ft
- Area
- 200 acres
Why Pine Mountain Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: 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 Pine Mountain Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
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.
Pine Mountain Lake is a 200-acre lake in Tuolumne County, California.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2021-07-13. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Pine Mountain Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Crystal clear, you can see 18 ft down. Trophic State Index: 35.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 18 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 35 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Pine Mountain Lake
Compare lakeside cabins, hotels, and vacation rentals near Pine Mountain Lake in Tuolumne 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 Pine Mountain Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 200 acres |
No bathymetric survey has been published for Pine Mountain Lake, so its depth is not documented here.
Fishing Pine Mountain Lake
Reservoir Info (USACE NID)
Pine Mountain Lake is a man-made reservoir impounded by the Big Creek (completed 1969), built primarily for water supply on the Big Creek; earth-type dam, 120 ft tall and 480 ft long.
- Surface area
- 200 ac
- Max storage
- 7,650 ac-ft
- Drainage area
- 25.6 sq mi
- Hazard class
- High
- Owner
- Pine Mountain Lake Association
All listed purposes: Water Supply;Recreation.
Source: USACE National Inventory of Dams, NID ID CA00652 · Operator website · Matched by proximity (0.81 km)
Graded lakes near Pine Mountain Lake
Pine Mountain Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Tuolumne County
Frequently asked questions about Pine Mountain Lake
Where is Pine Mountain Lake?
- Pine Mountain Lake is a lake in Tuolumne County, California. LakeQuality has not rated this lake (UNRATED) — there is not enough recent sampling to assign a letter.
What is the water quality grade for Pine Mountain Lake?
- Pine Mountain Lake in Tuolumne County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 18 ft visibility. Surface area: 200 acres.
Is Pine Mountain Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Pine Mountain Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Explore Pine Mountain Lake across LakeGrade
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Where this data comes from
1 measurement from 1 monitoring station, 2021. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- North American Lake Management Society
NALMS1 sample · 2021
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.