Olson dam
Olson
Olson, located in Napa, California, is a privately owned dam on Ledgewood Creek with a primary purpose of water supply for irrigation and other uses. Completed in 1955, this earth dam stands at a height of 45 feet and spans 646 feet in length, with a storage capacity of 200 acre-feet. The dam has a high hazard potential but is currently in satisfactory condition, last assessed in September 2017.
Regulated by the California Department of Water Resources for safety, Olson undergoes regular inspections and enforcement to ensure its integrity and compliance with state regulations. The dam's location in Palo Cedro, near San Francisco District, makes it a critical water resource for the region. While the dam has not been modified in recent years and lacks certain features like spillways and locks, its importance for water supply in the area cannot be understated.
Water resource and climate enthusiasts can appreciate the significance of Olson as a vital infrastructure for water management in California. With its historical significance, high hazard potential, and regulatory oversight, Olson serves as a key player in the state's water supply system. As climate change continues to impact water resources, understanding and monitoring dams like Olson is crucial for ensuring sustainable water management practices in the face of environmental challenges.
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 Olson -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Napa R Nr Napa Ca | 27 cfs | → |
| Putah C Nr Winters Ca | 585 cfs | → |
| Nathanson C A Sonoma Ca | 0 cfs | → |
| Shag Slough A Liberty Island Nr Courtland Ca | 3,500 cfs | → |
| Sonoma C A Agua Caliente Ca | 10 cfs | → |
| Napa R Nr St Helena Ca | 8 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Olson.
Boat launches
- Belden's Landing Boat Launch
- Napa Valley Vine Trail, Napa
- Cuttings Wharf Road 3175-3337, Napa
- Cuttings Wharf Road 3270, Napa
- Knoxville Road 1601, Napa County
- North Camino Alto Vallejo
Campgrounds
- Travis Afb Military
- Skyline Wilderness County Park
- Napa Valley Expo
- Lake Solano County Park
- Steele Canyon Camp Site
- Lupine Shores - Lake Berryessa - Usbr
Fishing spots
- 9th Street Boat Ramp
- Berryessa Lake
- City Of Benicia Fishing Pier
- Lake Berryessa
- Cliff House Fishing Access Area
- Contra Loma Reservoir
Paddle runs
- Headwaters To Mouth
- Headwaters To Ends One Quarter Mile South Of Bear Valley Road Bridge Segment 1: Ends 1/4 Mile South Of Bear Valley Road Bridge Segment 2: Caltrans Corporation Yard At Point Reyes Staton.
- Olema Ranch Campground To Caltrans Corporation Yard At Point Reyes Station
- Cache Creek
More reservoirs
Track Olson 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 Olson
Where does the data for Olson 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 Olson.