Ler Peters Canyon Retarding Basin is an earth dam located in Orange County, California, built in 1990. It carries a High hazard potential classification and has a satisfactory condition assessment.
Dam profile
NID height · 52 ft52 ft tall and 1,166 ft long, taller than 93% of U.S. dams with a recorded height. Height is drawn to scale against a ten-story building, about 100 ft; the profile is a generic embankment section and the water level is illustrative.
About Ler Peters Canyon Retarding Basin
The primary purpose of Ler Peters Canyon Retarding Basin is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by County of Orange (local government). It impounds the Peters Can Wash near Tustin.
The dam stands 52 feet tall and stretches 1,166 feet across, creates a reservoir covering 14 acres, has a maximum storage capacity of 206 acre-feet, and collects water from a drainage area of 2 square miles. Completed in 1990, the structure is 36 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 09/09/2025.
At 52 feet, this dam is taller than 93% of dams nationwide.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The California dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | California |
| County | Orange |
| Nearest City | Tustin |
| River/Stream | Peters Can Wash |
| Coordinates | 33.76030, -117.77260 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 52 ft |
| Dam Height | 52 ft |
| Dam Length | 1,166 ft |
| Year Completed | 1990 (36 years old) |
Storage & Hydraulics
| NID Storage | 206 acre-ft |
| Max Storage | 206 acre-ft |
| Surface Area | 14 acres |
| Drainage Area | 2 sq mi |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | County of Orange |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 09/09/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CA01207 |
| Federal ID | CA01207 |
| More Info | State Dam Safety Program |