Lanpher
Lanpher is an earth dam located in Allegheny County, Pennsylvania, built in 1915. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Lanpher
The primary purpose of Lanpher 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 Pittsburgh Water And Sewer Authority (local government). It impounds the Wtrshd Allegheny River.
The dam stands 38 feet tall and stretches 3,425 feet across, creates a reservoir covering 16 acres, and has a maximum storage capacity of 470 acre-feet. Completed in 1915, 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 satisfactory, indicating no existing or potential dam safety deficiencies are recognized. Notably, no emergency action plan is currently on file for this high-hazard dam. The most recent inspection on record was 03/05/2021.
At 38 feet, this dam is taller than 85% 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 Pennsylvania 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 | Pennsylvania |
| County | Allegheny |
| River/Stream | Wtrshd Allegheny River |
| Coordinates | 40.49194, -79.95972 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 38 ft |
| Dam Height | 38 ft |
| Dam Length | 3,425 ft |
| Year Completed | 1915 (111 years old) |
Storage & Hydraulics
| NID Storage | 470 acre-ft |
| Max Storage | 470 acre-ft |
| Normal Storage | 470 acre-ft |
| Surface Area | 16 acres |
Ownership & Safety
| Purpose | Water Supply |
| Owner | PITTSBURGH WATER AND SEWER AUTHORITY |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 03/05/2021 |
| Emergency Action Plan | No |
Identifiers
| NID ID | PA01980 |
| Federal ID | PA01980 |
| More Info | State Dam Safety Program |