Shepaug is a concrete dam located in New Haven County, Connecticut, built in 1955. It carries a High hazard potential classification and has a satisfactory condition assessment.
Dam profile
NID height · 138 ft138 ft tall and 1,412 ft long, taller than 99% of U.S. dams with a recorded height. Height is drawn to scale against a ten-story building, about 100 ft; the profile is a generic concrete gravity section and the water level is illustrative.
About Shepaug
The primary purpose of Shepaug is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Firstlight Power Services LLC (public utility). It impounds the Housatonic River near Berkshire Estates.
The dam stands 138 feet tall and stretches 1,412 feet across, creates a reservoir covering 1,870 acres, has a maximum storage capacity of 72,700 acre-feet, and collects water from a drainage area of 1,391 square miles. Completed in 1955, 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 07/27/2022.
At 138 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 | New Haven |
| Nearest City | Berkshire Estates |
| River/Stream | Housatonic River |
| Coordinates | 41.44790, -73.29640 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 138 ft |
| Dam Height | 138 ft |
| Dam Length | 1,412 ft |
| Year Completed | 1955 (71 years old) |
Storage & Hydraulics
| NID Storage | 72,700 acre-ft |
| Max Storage | 72,700 acre-ft |
| Normal Storage | 66,700 acre-ft |
| Surface Area | 1,870 acres |
| Drainage Area | 1,391 sq mi |
| Max Discharge | 162,000 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | Firstlight Power Services LLC |
| Owner Type | Public Utility |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 07/27/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CT00232 |
| Federal ID | CT00232 |
| More Info | State Dam Safety Program |