Metz Road Detention Basin
Metz Road Detention Basin is an earth dam located in Riverside County, California, built in 1981. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Metz Road Detention Basin
The primary purpose of Metz Road Detention 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 Riverside County Flood Control And Water Conservation District (local government). It impounds the Tr San Jacinto Riv near Perris.
The dam stands 12 feet tall and stretches 4,505 feet across, creates a reservoir covering 20 acres, has a maximum storage capacity of 88 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1981, the structure is 45 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 12/02/2025.
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 | Riverside |
| Nearest City | Perris |
| River/Stream | Tr San Jacinto Riv |
| Coordinates | 33.79070, -117.23140 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 12 ft |
| Dam Height | 12 ft |
| Dam Length | 4,505 ft |
| Year Completed | 1981 (45 years old) |
Storage & Hydraulics
| NID Storage | 88 acre-ft |
| Max Storage | 88 acre-ft |
| Surface Area | 20 acres |
| Drainage Area | 1 sq mi |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Riverside County Flood Control and Water Conservation District |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 12/02/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CA01197 |
| Federal ID | CA01197 |
| More Info | State Dam Safety Program |