Patch Reservoir Dam
Patch Reservoir Dam is a masonry dam located in Worcester County, Massachusetts, built in 1896. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Patch Reservoir Dam
The primary purpose of Patch 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 8 feet tall and stretches 70 feet across, creates a reservoir covering 34 acres, has a maximum storage capacity of 187 acre-feet, and collects water from a drainage area of 9 square miles. Completed in 1896, 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 05/01/2023.
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 | 42.26850, -71.85135 |
Physical Characteristics
| Dam Type | Masonry |
| NID Height | 8 ft |
| Dam Length | 70 ft |
| Year Completed | 1896 (130 years old) |
Storage & Hydraulics
| NID Storage | 187 acre-ft |
| Max Storage | 187 acre-ft |
| Normal Storage | 85 acre-ft |
| Surface Area | 34 acres |
| Drainage Area | 9 sq mi |
| Max Discharge | 950 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | City of Worcester |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/01/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MA00122 |
| Federal ID | MA00122 |
| More Info | State Dam Safety Program |