Black Rock Pond Dam
Black Rock Pond Dam is an earth dam located in Litchfield County, Connecticut, built in 1945. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Black Rock Pond Dam
The primary purpose of Black Rock Pond Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Connecticut Deep (state). It impounds the Purgatory Brook near Thomaston.
The dam stands 16 feet tall and stretches 160 feet across, creates a reservoir covering 9 acres, has a maximum storage capacity of 164 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1945, the structure is well-established, with more than 75 years 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 05/07/2024.
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 Connecticut 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 | Connecticut |
| County | Litchfield |
| Nearest City | Thomaston |
| River/Stream | Purgatory Brook |
| Coordinates | 41.65174, -73.09652 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 16 ft |
| Dam Height | 16 ft |
| Dam Length | 160 ft |
| Year Completed | 1945 (81 years old) |
Storage & Hydraulics
| NID Storage | 164 acre-ft |
| Max Storage | 164 acre-ft |
| Normal Storage | 92 acre-ft |
| Surface Area | 9 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 180 cfs |
Ownership & Safety
| Purpose | Recreation |
| Owner | Connecticut DEEP |
| Owner Type | State |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/07/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CT00633 |
| Federal ID | CT00633 |
| More Info | State Dam Safety Program |