[5] It stores energy for PJM Interconnection, a regional transmission organization in 13 states and the District of Columbia.

The upper reservoir on Little Back Creek has a surface area of 265 acres (107 ha) and storage capacity of 35,599 acre-feet (43,911,000 m3).

It has a structural volume of 4,000,000 cubic yards (3,100,000 m3) and creates a reservoir with a surface area of 555 acres (225 ha) and storage capacity of 27,927 acre-feet (34,447,000 m3).

The conduits each lead to a 990 feet (300 m) shaft which bifurcates into two penstocks (for a total of six) before reaching the turbines.

[8][10] Water is released from the upper reservoir during periods of high demand and is used to generate electricity.