Lower Rocky Glen Dam is a masonry dam located in Fairfield County, Connecticut, built in 1870. It carries a Significant hazard potential classification.
Dam profile
NID height · 18 ft18 ft tall and 135 ft long. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic concrete gravity section and the water level is illustrative.
About Lower Rocky Glen Dam
The primary purpose of Lower Rocky Glen Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Rocky Glen, LLC (public utility). It impounds the Pootatuck River near Rocky Glen.
The dam stands 18 feet tall and stretches 135 feet across, creates a reservoir covering 4 acres, has a maximum storage capacity of 43 acre-feet, and collects water from a drainage area of 24 square miles. Completed in 1870, the structure is one of the older dams in the region, with over a century and a half of service.
This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life.
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Location
| State | Connecticut |
| County | Fairfield |
| Nearest City | Rocky Glen |
| River/Stream | Pootatuck River |
| Coordinates | 41.42588, -73.28184 |
Physical Characteristics
| Dam Type | Masonry |
| NID Height | 18 ft |
| Dam Height | 18 ft |
| Dam Length | 135 ft |
| Year Completed | 1870 (156 years old) |
Storage & Hydraulics
| NID Storage | 43 acre-ft |
| Max Storage | 43 acre-ft |
| Surface Area | 4 acres |
| Drainage Area | 24 sq mi |
| Max Discharge | 4,800 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | Rocky Glen, LLC |
| Owner Type | Public Utility |
| Hazard Classification | Significant |
| Condition Assessment | Not assessed |
| Emergency Action Plan | No |
Identifiers
| NID ID | CT00311 |
| Federal ID | CT00311 |
| More Info | State Dam Safety Program |