Iron Hill Dam
Iron Hill Dam is a gravity dam located in Norfolk County, Massachusetts. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Iron Hill Dam
The primary purpose of Iron Hill Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Town Of Weymouth (local government). It impounds the Herring Brook near Weymouth.
The dam stands 26 feet tall and stretches 190 feet across, creates a reservoir covering 1 acres, has a maximum storage capacity of 33 acre-feet, and collects water from a drainage area of 12 square miles.
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 09/23/2022.
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 Massachusetts 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 | Massachusetts |
| County | Norfolk |
| Nearest City | Weymouth |
| River/Stream | Herring Brook |
| Coordinates | 42.21287, -70.92759 |
Physical Characteristics
| Dam Type | Gravity |
| NID Height | 26 ft |
| Dam Length | 190 ft |
Storage & Hydraulics
| NID Storage | 33 acre-ft |
| Max Storage | 33 acre-ft |
| Normal Storage | 25 acre-ft |
| Surface Area | 1 acres |
| Drainage Area | 12 sq mi |
| Max Discharge | 1,269 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Recreation |
| Owner | Town of Weymouth |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 09/23/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MA02492 |
| Federal ID | MA02492 |
| More Info | State Dam Safety Program |