Union Valley reservoir
Union Valley
Union Valley is a reservoir located in El Dorado County, California. The reservoir was created in 1963 with the construction of the Union Valley Dam, which is part of the American River watershed. The hydrology of Union Valley is primarily fed by the Rubicon River, and the reservoir provides water for hydroelectric power generation, irrigation, and municipal use. The area is also popular for recreational activities such as fishing, boating, camping, and hiking. The surrounding forests and hills are home to a diverse range of wildlife, including deer, elk, and black bears. The Union Valley Snowpack, which is a significant provider of water to the region, is particularly important for the agricultural community, with crops such as potatoes, grapes, and apples requiring water from the snowpack for irrigation.
Daily levels at Union Valley
Storage volume, pool elevation, and total release plotted from the operating agency's daily observations.
Storage
acre-ft · code 2
Pool Elevation
ft · code 1
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Union Valley -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Pilot C Ab Stumpy Meadows Res Ca | 3 cfs | → |
| Pilot C Bl Mutton Canyon Nr Georgetown Ca | 2 cfs | → |
| General C Nr Meeks Bay Ca | 15 cfs | → |
| Upper Truckee R At Hwy 50 Above Meyers Ca | 188 cfs | → |
| Blackwood C Nr Tahoe City Ca | 73 cfs | → |
| Upper Truckee R At S Upper Truckee Rd Nr Meyers Ca | 4 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Union Valley.
Boat launches
- Junction Boat Ramp Road El Dorado County
- Dry Lakes Trail El Dorado County
- Poho Ridge El Dorado County
- Ice House Road El Dorado County
- Forebay Road El Dorado County
- Sly Park Road, Pollock Pines
Campgrounds
Fishing spots
Paddle runs
- Ellicots Bridge To Big Grizzly Canyon
- Big Grizzly Canyon To Oxbow Reservoir
- Hell Hole Dam To Ellicotts Bridge
- Confluence With Van Horn Creek To Cosumnes Mine Road
- Interbay To Oxbow (End Of The World)
- Cosumnes Mine Road To Confluence With Steely Fork Cosumnes River
More reservoirs
Track Union Valley in the Snoflo app
Save this reservoir as a favorite and set push alerts when storage crosses a threshold (e.g. "alert me at 80% of normal").
About Union Valley
Where does the data for Union Valley come from?
Daily storage, pool elevation, and release rates are sourced from USGS, USBR, and USACE monitoring stations. Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
Storage observations are updated daily by the operating agency. The 15-day weather forecast refreshes throughout the day. Snoflo caches and renders the most recent observation -- check the "as of" timestamp on the storage card.
What does the Hazard hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this reservoir, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Union Valley.