Ligonier Reservoir
Ligonier Reservoir is an earth dam located in Westmoreland County, Pennsylvania, built in 1954. It carries a High hazard potential classification and has a fair condition assessment.
About Ligonier Reservoir
The primary purpose of Ligonier Reservoir 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 Ligonier Township Authority (local government). It impounds the South Fork Mill Creek.
The dam stands 35 feet tall and stretches 510 feet across, creates a reservoir covering 5 acres, has a maximum storage capacity of 64 acre-feet, and collects water from a drainage area of 2 square miles. Completed in 1954, the structure is well into its service life at over 50 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 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 09/23/2020.
At 35 feet, this dam is taller than 82% 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 | Westmoreland |
| River/Stream | South Fork Mill Creek |
| Coordinates | 40.23722, -79.14611 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 35 ft |
| Dam Height | 35 ft |
| Dam Length | 510 ft |
| Year Completed | 1954 (72 years old) |
Storage & Hydraulics
| NID Storage | 64 acre-ft |
| Max Storage | 64 acre-ft |
| Normal Storage | 45 acre-ft |
| Surface Area | 5 acres |
| Drainage Area | 2 sq mi |
Ownership & Safety
| Purpose | Water Supply |
| Owner | LIGONIER TOWNSHIP AUTHORITY |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 09/23/2020 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | PA00477 |
| Federal ID | PA00477 |
| More Info | State Dam Safety Program |