Sanborn Sawmill Dam
Sanborn Sawmill Dam is an earth dam located in Merrimack County, New Hampshire, built in 1830. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Sanborn Sawmill Dam
Sanborn Sawmill Dam is a dam in Merrimack, New Hampshire. The dam is owned by Sanborn Mills Inc (private). It impounds the Sanborn Brook near Loudon.
The dam stands 13 feet tall and stretches 156 feet across, creates a reservoir covering 0 acres, has a maximum storage capacity of 2 acre-feet, and collects water from a drainage area of 4 square miles. Completed in 1830, the structure is one of the older dams in the region, with over a century and a half of service.
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 11/04/2021.
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 | Merrimack |
| Nearest City | Loudon |
| River/Stream | Sanborn Brook |
| Coordinates | 43.33340, -71.38406 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 13 ft |
| Dam Height | 13 ft |
| Dam Length | 156 ft |
| Year Completed | 1830 (196 years old) |
Storage & Hydraulics
| NID Storage | 2 acre-ft |
| Max Storage | 2 acre-ft |
| Normal Storage | 1 acre-ft |
| Surface Area | 0 acres |
| Drainage Area | 4 sq mi |
| Max Discharge | 645 cfs |
Ownership & Safety
| Purpose | Other |
| Owner | SANBORN MILLS INC |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 11/04/2021 |
| Emergency Action Plan | No |
Identifiers
| NID ID | NH02411 |
| Federal ID | NH02411 |
| More Info | State Dam Safety Program |