Monticello dam
Monticello
Monticello, also known as Lake Berryessa, is a Federal-owned water resource located in Napa, California. Constructed in 1957 by the Bureau of Reclamation, Monticello serves primarily for irrigation purposes and water supply. The dam, standing at a height of 255 feet, holds a maximum storage capacity of 1,854,819 acre-feet, with a normal storage capacity of 1,602,278 acre-feet.
With a surface area of 20,240 acres and a drainage area of 576 square miles, Monticello plays a crucial role in managing water resources in the region. The dam utilizes an uncontrolled spillway type with a width of 67 feet. The facility has a high hazard potential and undergoes regular inspections by the Bureau of Reclamation to ensure its structural integrity and safety. Despite its age, Monticello continues to be a vital asset for irrigation and water supply needs in the area.
Situated along Putah Creek, Monticello offers a picturesque setting for water resource and climate enthusiasts to explore. With its impressive architectural design and significant storage capacity, Monticello stands as a testament to the ingenuity and importance of water infrastructure in California. As a key component of the region's water management system, Monticello plays a critical role in sustaining agricultural activities and ensuring a reliable water supply for the surrounding communities.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.
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 Monticello -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Putah C Nr Winters Ca | 548 cfs | → |
| Napa R Nr Napa Ca | 27 cfs | → |
| Napa R Nr St Helena Ca | 8 cfs | → |
| Cache C A Yolo Ca | · | → |
| Sonoma C A Agua Caliente Ca | 10 cfs | → |
| Nathanson C A Sonoma Ca | 0 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Monticello.
Boat launches
- Knoxville Road 1601, Napa County
- Chaparral Cove Napa County
- Napa Valley Vine Trail, Napa
- Cuttings Wharf Road 3175-3337, Napa
- Cuttings Wharf Road 3270, Napa
- Belden's Landing Boat Launch
Campgrounds
- Lake Solano County Park
- Steele Canyon Camp Site
- Lupine Shores - Lake Berryessa - Usbr
- Lupine Shores Camp Site
- Foothill Pines - Lake Berryessa - Usbr
- Spanish Flat Camp Site
Fishing spots
- Berryessa Lake
- Lake Berryessa
- Lake Ralphine
- 9th Street Boat Ramp
- City Of Benicia Fishing Pier
- Cliff House Fishing Access Area
Paddle runs
- Cache Creek
- Sunrise Avenue To Watt Avenue
- Olema Ranch Campground To Caltrans Corporation Yard At Point Reyes Station
More reservoirs
Track Monticello in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Monticello
Where does the data for Monticello come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the High 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 dam, 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 Monticello.