Thermalito Afterbay reservoir
Thermalito Afterbay
Thermalito Afterbay is a man-made reservoir located in Butte County, California. It was constructed in the 1960s as a part of the Oroville-Thermalito Complex and was designed to provide a place to store and regulate water released from Oroville Dam. The afterbay has a capacity of 210,000 acre-feet and covers approximately 4,000 acres.
The hydrology of Thermalito Afterbay is influenced by both surface flow and snowpack. The reservoir receives water from the Feather River via the Feather River Diversion Pool, and from the Thermalito Diversion Dam. The afterbay also receives water from snowpack runoff during the spring and summer months.
The primary agricultural uses of Thermalito Afterbay are for irrigation and fish farming. The reservoir is also used for recreational purposes, such as fishing, boating, and swimming.
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 Thermalito Afterbay -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Butte C Nr Chico Ca | 180 cfs | → |
| Yuba R Nr Marysville Ca | 528 cfs | → |
| Deer C Nr Smartville Ca | 6 cfs | → |
| Sacramento R A Colusa Ca | 8,460 cfs | → |
| Sacramento R Bl Wilkins Slough Nr Grimes Ca | 6,880 cfs | → |
| Bear R Nr Wheatland Ca | 26 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Thermalito Afterbay.
Boat launches
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Campgrounds
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Fishing spots
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River runs
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About Thermalito Afterbay
Where does the data for Thermalito Afterbay 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 below 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.