Union Valley Reservoir
Union Valley Reservoir in El Dorado County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 2735 acres.
- Area
- 2,735 acres
- Public access
- Yes
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Why Union Valley Reservoir 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 Union Valley Reservoir, 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.
Union Valley Reservoir is a 2,735-acre lake in El Dorado County, California. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Union Valley Reservoir 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 Union Valley Reservoir
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 Union Valley Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Union Valley Reservoir in El Dorado 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 Union Valley Reservoir
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 2,735 acres |
| Public Access | Yes |
No bathymetric survey has been published for Union Valley Reservoir, so its depth is not documented here.
Recreation & Access
- Union Valley Reservoir - PeninsulaPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Union Valley Reservoir
Nearby Lakes in El Dorado County
Frequently asked questions about Union Valley Reservoir
Where is Union Valley Reservoir?
- Union Valley Reservoir is a lake in El Dorado 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 Union Valley Reservoir?
- Union Valley Reservoir in El Dorado County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 2735 acres.
Is Union Valley Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Union Valley Reservoir 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 Union Valley Reservoir?
- Union Valley Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Union Valley Reservoir - Peninsula. Public access is listed as yes.
Explore Union Valley Reservoir across LakeQuality
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Where this data comes from
Measurements for Union Valley Reservoir 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