Concrete pouring completed for deep excavation pit in Shanghai sewer

Concrete pouring has been completed for the base slab of a 47.3-meter-deep rectangular excavation pit, marking a milestone in the construction of a vital sewage pumping station in the city, according to the municipal water authority on Tuesday.

The benchmark facility, located near Zhouhai Road in Pudong New Area, serves as a critical transfer hub for the phase I relief line of the Shanghai integrated sewerage system, a key municipal environmental initiative.

Reaching a depth equivalent to a 15-story residential building, it is by far the deepest excavation pit of its kind in Shanghai.

The excavation faced challenges due to complex, soft soil and high groundwater pressure. To address these, engineers constructed a 95-meter-deep underground diaphragm wall and executed a continuous pour of 4,430 cubic meters of concrete to form the station's 2.5-meter-thick base slab.

Once operational, the pumping station will cover 81 square kilometers across six central districts of Shanghai. The facility is designed to help move sewage across areas in emergencies, allow maintenance on existing main sewer pipes, improve the interception of polluted stormwater runoff, and reinforce the city's flood control system.

Ma Tan contributed to this story.