San Dimas dam
San Dimas
San Dimas, also known as San Dimas Reservoir, is a gravity dam located in La Verne, California, that serves as a crucial flood risk reduction structure along the San Dimas Creek. Completed in 1922, this dam stands at a height of 131 feet and has a storage capacity of 1,534 acre-feet, providing essential water supply for irrigation and other purposes. Managed by the local government, the dam is regulated and inspected by the Department of Water Resources (DWR) for safety and enforcement.
With a high hazard potential but a satisfactory condition assessment as of September 2017, San Dimas Dam undergoes regular inspections to ensure its continued functionality and structural integrity. It is equipped with emergency action plans and updated contact information to handle any potential risks or emergencies effectively. The surrounding area, covering a surface area of 36 acres and draining 15.9 square miles, benefits from the flood risk reduction provided by this vital infrastructure.
San Dimas Dam not only plays a significant role in flood risk reduction but also contributes to irrigation and water supply in the region. Its historical significance, dating back nearly a century, underscores the importance of maintaining and monitoring this structure to safeguard the local community and water resources in Los Angeles County, California.
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 San Dimas -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| San Antonio C A Riverside Dr Nr Chino Ca | · | → |
| Chino C A Schaefer Avenue Nr Chino Ca | 0 cfs | → |
| San Gabriel R Bl Santa Fe Dam Nr Baldwin Pk Ca | 171 cfs | → |
| Cucamonga C Nr Mira Loma Ca | 23 cfs | → |
| Carbon C Bl Carbon Cyn Dam Ca | · | → |
| San Gabriel R Ab Whittier Narrows Dam Ca | 30 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near San Dimas.
Boat launches
Campgrounds
Fishing spots
- Puddingstone Reservoir
- Puddingstone Lake
- Mt Baldy Trout Pools
- Santa Fe Dam
- Cucamonga-Guasti Regional Park Lake
- Peck Road Park Lake
Paddle runs
- Laurel Gulch To Confluence With Mineo Canyon (Se 1/4, Sw 1/4, Sec 17, T2n, R8w)
- North Fork - Confluence Of Soldier And Coldbrook Creeks (Se1/4,Sw1/4, Sec) 5, T2n,,R9w To Conflluence With West Fork Of San Gabriel (Sw 1/4,Sw1/4, Sec 17, T2n, R8w)
- Gaging Station Below Spillway Of Cogswell Dam (Ne 1/4, Se 1/4, Sec 19, T2n, R10w) To Confluence With Nf San Gabriel River (Sw 1/4.Sw 1/4, Sec 15, T2n, R9w)
- East Fork - Confluence Of Vincent Gulch And Prairie Fork (Nw 1/4, Sw 1/4 Sec 16 ) To Laurel Gulch (Nw 1/4, Sw 1/4, Sec 17, T2n, R8w)
- Middle Fork - Commanche Campsite To Middle Fork Trailhead
- Mainstream - Headwaters To Confluence With Cooper Canyon
Track San Dimas 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 San Dimas
Where does the data for San Dimas 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 San Dimas.