Devils Gate dam
Devils Gate
Devils Gate, located in Pasadena, California, is a gravity dam constructed in 1920 for the primary purpose of flood risk reduction along the Arroyo Seco river. With a height of 108 feet and a storage capacity of 2600 acre-feet, this dam plays a crucial role in managing water resources in the region. The structure is regulated by the California Department of Water Resources (DWR) and undergoes regular inspections to ensure its safety and effectiveness.
Despite being classified as having a high hazard potential, Devils Gate is assessed as being in satisfactory condition as of September 2017. The dam's last inspection in October 2020 confirmed its structural integrity and readiness to handle potential emergencies. With Judy Chu (D) as the congressional representative for the area, the local government takes responsibility for the ownership and operation of Devils Gate, highlighting the collaborative efforts to safeguard the community from flood risks and ensure water supply sustainability.
As a significant part of the flood risk reduction infrastructure in Los Angeles County, Devils Gate serves as a vital resource for water management in the region. Its strategic location and design contribute to the protection of surrounding areas from potential inundation, showcasing the importance of proactive measures in mitigating climate-related challenges. With ongoing regulatory oversight and regular maintenance, Devils Gate stands as a testament to effective water resource management and climate resilience efforts in Southern 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 Devils Gate -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Arroyo Seco Nr Pasadena Ca | 6 cfs | → |
| Rio Hondo Ab Whittier Narrows Dam Ca | 65 cfs | → |
| Rio Hondo Bl Whittier Narrows Dam Ca | 11 cfs | → |
| San Gabriel R Bl Santa Fe Dam Nr Baldwin Pk Ca | 151 cfs | → |
| San Gabriel R Ab Whittier Narrows Dam Ca | 15 cfs | → |
| Big Tujunga C Bl Hansen Dam Ca | · | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Devils Gate.
Boat launches
Campgrounds
Fishing spots
Paddle runs
- West Fork - Headwaters (Se 1/4, Ne 1/4, Sec 14, T2n, R12w) To Cogswell Reservoir (Ne 1/4, Sw 1/4, Sec 24, T2n, R9w
- 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)
- Cooper Canyon- Near State Highway 2 (Sw 1/4, Ne 1/4, Sec 16, T3n, R10w To Confluence With Little Rock Creek
- Mainstream - Confluence With South Fork Little Rock Creek To Little Rock Creek Reservoir
- Mainstream - Confluence With Cooper Canyon To Confluence Wit South Fork Little Rock Creek
- 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)
Track Devils Gate 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 Devils Gate
Where does the data for Devils Gate 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 Devils Gate.