Black Rock is a timber crib dam located in Montgomery County, Pennsylvania, built in 1900. It carries a Low hazard potential classification and has a satisfactory condition assessment.
Dam profile
NID height · 11 ft11 ft tall and 400 ft long. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.
About Black Rock
The primary purpose of Black Rock 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 Exelon Generation Company (private). It impounds the Schuylkill River.
The dam stands 11 feet tall and stretches 400 feet across, creates a reservoir covering 184 acres, has a maximum storage capacity of 221 acre-feet, and collects water from a drainage area of 1,296 square miles. Completed in 1900, the structure is over a century old.
This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. The most recent inspection on record was 07/27/2018.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Pennsylvania |
| County | Montgomery |
| River/Stream | Schuylkill River |
| Coordinates | 40.14806, -75.50639 |
Physical Characteristics
| Dam Type | Timber Crib |
| NID Height | 11 ft |
| Dam Height | 11 ft |
| Dam Length | 400 ft |
| Year Completed | 1900 (126 years old) |
Storage & Hydraulics
| NID Storage | 221 acre-ft |
| Max Storage | 221 acre-ft |
| Normal Storage | 221 acre-ft |
| Surface Area | 184 acres |
| Drainage Area | 1,296 sq mi |
Ownership & Safety
| Purpose | Water Supply |
| Owner | Exelon Generation Company |
| Owner Type | Private |
| Hazard Classification | Low |
| Condition Assessment | Satisfactory |
| Last Inspection | 07/27/2018 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | PA00884 |
| Federal ID | PA00884 |
| More Info | State Dam Safety Program |