Bostwicks Pond Dam Reservoir Report

Last Updated: December 5, 2025

Bostwicks Pond Dam, located in Upper Deerfield Township, New Jersey, is a significant earth dam that was completed in 1934 for recreational purposes.


°F

°F

mph

Wind

%

Humidity

Summary

With a height of 13 feet and a length of 730 feet, the dam holds back the waters of the Cohansey River, creating a surface area of 40 acres and a drainage area of 8.3 square miles. The dam has a storage capacity of 52 acre-feet and a maximum discharge of 2952 cubic feet per second.

Managed by the local government and regulated by the New Jersey Department of Environmental Protection (NJDEP), Bostwicks Pond Dam is inspected regularly to ensure its structural integrity. The dam is classified as having a significant hazard potential, although its condition assessment is currently rated as satisfactory. Emergency action plans have been prepared and updated in accordance with guidelines, with the last revision dating back to October 2017. The dam is not owned or funded by any federal agencies.

For water resource and climate enthusiasts, Bostwicks Pond Dam presents an interesting case study in dam management and regulation. Its location in Cumberland County, New Jersey, along with its association with the Cohansey River, adds to its ecological significance. With its historical construction in the 1930s and ongoing maintenance to meet safety standards, the dam serves as a key recreational asset while also fulfilling its role in flood control and water supply management for the surrounding area.

Year Completed

1934

Dam Length

730

Dam Height

13

River Or Stream

Cohansey River

Primary Dam Type

Earth

Surface Area

40

Drainage Area

8.3

Nid Storage

52

Hazard Potential

Significant

Nid Height

13
       
Seasonal Comparison

Weather Forecast

Dam Data Reference

Condition Assessment

Satisfactory
No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.

Hazard Potential Classification

High
Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.