Coes Reservoir Dam
Coes Reservoir Dam is an earth dam located in Worcester County, Massachusetts, built in 1865. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Coes Reservoir Dam
The primary purpose of Coes Reservoir Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by City Of Worcester (local government). It impounds the Tatnuck Brook near Worcester.
The dam stands 21 feet tall and stretches 600 feet across, creates a reservoir covering 90 acres, has a maximum storage capacity of 1,223 acre-feet, and collects water from a drainage area of 11 square miles. Completed in 1865, 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. An emergency action plan is in place for this dam. The most recent inspection on record was 02/21/2023.
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 | Worcester |
| Nearest City | Worcester |
| River/Stream | Tatnuck Brook |
| Coordinates | 42.25080, -71.83740 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 21 ft |
| Dam Length | 600 ft |
| Year Completed | 1865 (161 years old) |
Storage & Hydraulics
| NID Storage | 1,223 acre-ft |
| Max Storage | 1,223 acre-ft |
| Normal Storage | 672 acre-ft |
| Surface Area | 90 acres |
| Drainage Area | 11 sq mi |
| Max Discharge | 2,866 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | City of Worcester |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 02/21/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MA00120 |
| Federal ID | MA00120 |
| More Info | State Dam Safety Program |