Mad River Flood Control Dam
Mad River Flood Control Dam is an earth dam located in Litchfield County, Connecticut, built in 1963. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Mad River Flood Control Dam
The primary purpose of Mad River Flood Control Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Connecticut Deep (state). It impounds the Mad River near Winchester.
The dam stands 178 feet tall and stretches 940 feet across, creates a reservoir covering 10 acres, has a maximum storage capacity of 11,300 acre-feet, and collects water from a drainage area of 18 square miles. Completed in 1963, the structure is well into its service life at over 50 years 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 05/25/2023.
At 178 feet, this dam is taller than 99% of all dams in the United States.
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 | Winchester |
| River/Stream | Mad River |
| Coordinates | 41.93154, -73.09059 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 178 ft |
| Dam Height | 178 ft |
| Dam Length | 940 ft |
| Year Completed | 1963 (63 years old) |
Storage & Hydraulics
| NID Storage | 11,300 acre-ft |
| Max Storage | 11,300 acre-ft |
| Normal Storage | 11,300 acre-ft |
| Surface Area | 10 acres |
| Drainage Area | 18 sq mi |
| Max Discharge | 29,600 cfs |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Connecticut DEEP |
| Owner Type | State |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/25/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CT00500 |
| Federal ID | CT00500 |
| More Info | State Dam Safety Program |