Longwood Lake Dam in Jefferson Township, Morris County, New Jersey, stands as a historic stone structure completed in 1898 for the primary purpose of recreation along the Rockaway River.
Wind
Humidity
With a height of 21.5 feet and a length of 91 feet, this dam stores a maximum of 351 acre-feet of water with a normal storage capacity of 214 acre-feet, covering a surface area of 43 acres. Despite its picturesque setting, Longwood Lake Dam has been classified with a high hazard potential and poor condition assessment, signaling a need for regular inspections and potential maintenance.
Managed by the local government, Longwood Lake Dam falls under the regulatory oversight of the New Jersey Department of Environmental Protection (NJDEP), ensuring compliance with state permitting, inspection, and enforcement requirements. The dam's last inspection in July 2021 revealed its poor condition, highlighting the urgency for necessary repairs or maintenance to mitigate the risks associated with its high hazard potential. It is crucial for water resource and climate enthusiasts to monitor the status of Longwood Lake Dam and advocate for its preservation to ensure the safety of surrounding communities and the sustainability of the Rockaway River ecosystem.
Year Completed |
1898 |
Dam Length |
91 |
Dam Height |
21.5 |
River Or Stream |
Rockaway River |
Primary Dam Type |
Stone |
Surface Area |
43 |
Drainage Area |
19 |
Nid Storage |
351 |
Hazard Potential |
High |
Nid Height |
22 |