Gregg Falls
Gregg Falls is a concrete dam located in Hillsborough, New Hampshire, built in 1917. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Gregg Falls
The primary purpose of Gregg Falls is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is state-owned. It impounds the Piscataquog River near Pinardville.
The dam stands 66 feet tall and stretches 1,360 feet across, creates a reservoir covering 138 acres, has a maximum storage capacity of 3,650 acre-feet, and collects water from a drainage area of 200 square miles. Completed in 1917, 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. An emergency action plan is in place for this dam. The most recent inspection on record was 05/25/2022.
At 66 feet, this dam is taller than 96% of all dams in the United States.
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 New Hampshire 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 | New Hampshire |
| County | Hillsborough |
| Nearest City | Pinardville |
| River/Stream | Piscataquog River |
| Coordinates | 43.01680, -71.56810 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 66 ft |
| Dam Height | 66 ft |
| Dam Length | 1,360 ft |
| Year Completed | 1917 (109 years old) |
Storage & Hydraulics
| NID Storage | 3,650 acre-ft |
| Max Storage | 3,650 acre-ft |
| Normal Storage | 3,650 acre-ft |
| Surface Area | 138 acres |
| Drainage Area | 200 sq mi |
| Max Discharge | 40,000 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner Type | State |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/25/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | NH00093 |
| Federal ID | NH00093 |
| More Info | State Dam Safety Program |