Split Rock Pond Dam
Split Rock Pond Dam is a concrete dam located in Morris County, New Jersey, built in 1948. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Split Rock Pond Dam
The primary purpose of Split Rock Pond 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 Jersey City Municipal Utilities Authority (local government). It impounds the Beaver Brook near Rockaway.
The dam stands 39 feet tall and stretches 490 feet across, creates a reservoir covering 566 acres, has a storage capacity of 9,517 acre-feet, and collects water from a drainage area of 5 square miles. Completed in 1948, the structure is well-established, with more than 75 years 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 05/13/2024.
At 39 feet, this dam is taller than 86% 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 New Jersey 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 | New Jersey |
| County | Morris |
| Nearest City | Rockaway |
| River/Stream | Beaver Brook |
| Coordinates | 40.96332, -74.45990 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 39 ft |
| Dam Height | 39 ft |
| Dam Length | 490 ft |
| Year Completed | 1948 (78 years old) |
Storage & Hydraulics
| NID Storage | 9,517 acre-ft |
| Normal Storage | 9,517 acre-ft |
| Surface Area | 566 acres |
| Drainage Area | 5 sq mi |
Ownership & Safety
| Purpose | Water Supply |
| Owner | Jersey City Municipal Utilities Authority |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/13/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | NJ00264 |
| Federal ID | NJ00264 |
| More Info | State Dam Safety Program |