Maltby No. 1 Dam
Maltby No. 1 Dam is an earth dam located in New Haven County, Connecticut, built in 1862. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Maltby No. 1 Dam
The primary purpose of Maltby No. 1 Dam is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by South Central Ct Rwa (public utility). It impounds the Unnamed Tributary To West River near West Haven.
The dam stands 37 feet tall and stretches 240 feet across, creates a reservoir covering 22 acres, has a maximum storage capacity of 260 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1862, 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 04/16/2024.
At 37 feet, this dam is taller than 84% of dams nationwide.
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 | West Haven |
| River/Stream | Unnamed Tributary To West River |
| Coordinates | 41.30554, -72.97352 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 37 ft |
| Dam Height | 26 ft |
| Dam Length | 240 ft |
| Year Completed | 1862 (164 years old) |
Storage & Hydraulics
| NID Storage | 260 acre-ft |
| Max Storage | 260 acre-ft |
| Normal Storage | 161 acre-ft |
| Surface Area | 22 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 520 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | South Central CT RWA |
| Owner Type | Public Utility |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 04/16/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CT00111 |
| Federal ID | CT00111 |
| More Info | State Dam Safety Program |