Bellamy Reservoir Dam
Bellamy Reservoir Dam is a concrete dam located in Strafford County, New Hampshire, built in 1962. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Bellamy Reservoir Dam
The primary purpose of Bellamy Reservoir Dam 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 City Of Portsmouth Pwd (local government). It impounds the Bellamy River near Madbury.
The dam stands 35 feet tall and stretches 462 feet across, creates a reservoir covering 333 acres, has a maximum storage capacity of 3,996 acre-feet, and collects water from a drainage area of 21 square miles. Completed in 1962, 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 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 11/15/2021.
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 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 | Strafford |
| Nearest City | Madbury |
| River/Stream | Bellamy River |
| Coordinates | 43.17970, -70.94940 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 35 ft |
| Dam Height | 35 ft |
| Dam Length | 462 ft |
| Year Completed | 1962 (64 years old) |
Storage & Hydraulics
| NID Storage | 3,996 acre-ft |
| Max Storage | 3,996 acre-ft |
| Normal Storage | 1,665 acre-ft |
| Surface Area | 333 acres |
| Drainage Area | 21 sq mi |
| Max Discharge | 19,674 cfs |
Ownership & Safety
| Purpose | Water Supply |
| Owner | CITY OF PORTSMOUTH PWD |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 11/15/2021 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | NH00471 |
| Federal ID | NH00471 |
| More Info | State Dam Safety Program |