New Bong Escape Hydropower

When the Mangla Dam was constructed in the sixties, they had to decide between releasing water directly into River Jhelum, or into a new canal with a flatter gradient. Releasing the water into a new canal would give an additional 20 feet head at the Mangla powerhouse. This led to construction of Bong Canal and New Bong Escape (NBE), 8km downstream, to release water into River Jhelum with a fall of 18 feet.

Waterflows from Mangla powerhouse are diverted to Upper Jhelum Canal (UJC) through the UJC Regulator to meet downstream irrigation needs with any excess flows spilt into River Jhelum through the NBE. The project was designed to utilize water releases through NBE for power generation. A unique feature is that NBE has been adapted to act as the project spillway for emergency water release upon sudden shutdown of the plant.

The project comprises a concrete lined headrace channel located next to New Bong Escape to draw water from Bong Canal and feed four Kaplan bulb turbine-generator units. The powerhouse is a conventional reinforced concrete structure that is founded on alluvial soils with high water level, requiring measures to control seepage into the foundation excavations and cut offs for long-term seepage control.