Green Oaks #1 dam
Green Oaks #1
Green Oaks #1 is a privately owned earth dam located in San Mateo County, California, along Green Oaks Creek. Completed in 1936, the dam stands at 39 feet high and has a storage capacity of 322 acre-feet. Its primary purpose is flood risk reduction, with additional benefits including hydroelectric power generation and water supply.
The dam is regulated and inspected by the California Department of Water Resources under the Safety of Dams program. As of the last inspection in March 2021, the dam was deemed to have a low hazard potential and satisfactory condition. The surrounding area has a drainage area of 1.08 square miles and a surface area of 22 acres, providing essential protection against flooding for the community.
Overall, Green Oaks #1 serves as a vital infrastructure for water resource management in the region, contributing to flood control, water supply, and environmental protection along Green Oaks Creek. With a history dating back over 80 years, the dam continues to demonstrate its importance in safeguarding the surrounding area from potential risks associated with extreme weather events and climate change impacts.
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 Green Oaks #1 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Pescadero C Nr Pescadero Ca | 16 cfs | → |
| San Gregorio C A San Gregorio Ca | 13 cfs | → |
| San Lorenzo R A Big Trees Ca | 44 cfs | → |
| Saratoga C A Saratoga Ca | 4 cfs | → |
| San Lorenzo R A Santa Cruz Ca | 43 cfs | → |
| San Francisquito C A Stanford University Ca | 6 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Green Oaks #1.
Boat launches
- Stevens Creek Reservoir
- Palo Alto Boat Launch
- San Francisco Bay Trail East Palo Alto
- Santa Clara County
- Sawyer Camp Trail San Mateo County
- Whidbey Lane Redwood City
Campgrounds
- Camp Herbert Trail Camp
- Twin Redwoods Trail Camp
- Alder Trail Camp
- Rancho Del Oso Horse Camp
- Sunset Trail Camp
- Nephi Trail Camp
Fishing spots
Paddle runs
More reservoirs
Track Green Oaks #1 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 Green Oaks #1
Where does the data for Green Oaks #1 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 Low 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 Green Oaks #1.