Ler Twin Lake
Ler Twin Lake is an earth dam located in Mono County, California, built in 1888. It carries a High hazard potential classification and has a fair condition assessment.
About Ler Twin Lake
The primary purpose of Ler Twin Lake is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Centennial Livestock (private). It impounds the Robinson Creek near Bridgeport.
The dam stands 16 feet tall and stretches 240 feet across, creates a reservoir covering 399 acres, has a maximum storage capacity of 4,011 acre-feet, and collects water from a drainage area of 39 square miles. Completed in 1888, the structure is over a century 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 fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 10/24/2024.
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 | Mono |
| Nearest City | Bridgeport |
| River/Stream | Robinson Creek |
| Coordinates | 38.16790, -119.32610 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 16 ft |
| Dam Height | 16 ft |
| Dam Length | 240 ft |
| Year Completed | 1888 (138 years old) |
Storage & Hydraulics
| NID Storage | 4,011 acre-ft |
| Max Storage | 4,011 acre-ft |
| Surface Area | 399 acres |
| Drainage Area | 39 sq mi |
Ownership & Safety
| Purpose | Water Supply |
| Owner | Centennial Livestock |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 10/24/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CA00644 |
| Federal ID | CA00644 |
| More Info | State Dam Safety Program |