Otis Reservoir Dam
Otis Reservoir Dam is an earth dam located in Berkshire County, Massachusetts, built in 1888. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Otis Reservoir Dam
The primary purpose of Otis Reservoir Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Ma Department Of Conservation & Recreation (state). It impounds the Fall River near Otis.
The dam stands 32 feet tall and stretches 630 feet across, creates a reservoir covering 1,000 acres, has a maximum storage capacity of 27,500 acre-feet, and collects water from a drainage area of 16 square miles. Completed in 1888, 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 06/21/2023.
At 32 feet, this dam is taller than 76% 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 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 | Berkshire |
| Nearest City | Otis |
| River/Stream | Fall River |
| Coordinates | 42.15886, -73.05863 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 32 ft |
| Dam Length | 630 ft |
| Year Completed | 1888 (138 years old) |
Storage & Hydraulics
| NID Storage | 27,500 acre-ft |
| Max Storage | 27,500 acre-ft |
| Normal Storage | 22,000 acre-ft |
| Surface Area | 1,000 acres |
| Drainage Area | 16 sq mi |
| Max Discharge | 4,700 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Recreation |
| Owner | MA Department of Conservation & Recreation |
| Owner Type | State |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 06/21/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MA00308 |
| Federal ID | MA00308 |
| More Info | State Dam Safety Program |