Beneath this unassuming facade lies a critical piece of infrastructure. This is the Sheung Wan Salt Water Pumping Station. But what does it do and why is it so important?
Sheung Wan is one of Hong Kong’s earliest settlements. Its drainage infrastructure was designed decades ago. These original designs could not handle modern urban development. The area around Bonham Strand and Wing Lok Street is particularly low-lying. It is prone to flooding during heavy rainstorms. High tides make the situation worse. Seawater can flow back from the harbor. It spills over from manholes and gratings.
Between 2001 and 2006, Sheung Wan experienced three serious floods. Flood depths reached up to 700 mm. This severely affected the area’s famous dried seafood shops and residents. The Drainage Services Department committed to solving this problem. They initiated the Sheung Wan Stormwater Pumping Station project.
This pumping station cost around HK$200 million. It was commissioned in 2009. The Sheung Wan Stormwater Pumping Station includes several key components. There is a 9000 cubic meter underground storage tank. This is about the size of four standard swimming pools. An above-ground pump house also exists. A diversion chamber with penstocks completes the structure.
The pump house stands 5.6 meters high. It has two basement levels. Inside, you will find a switch room, transformer room, and water pumps. A deodorization unit keeps the air fresh.
The operation of the Sheung Wan Stormwater Pumping Station is simple. The diversion chamber is located downstream of a 2.1-meter diameter drainage pipe. This chamber diverts runoff from the low-lying area into the underground storage tank. At the same time, the penstocks close to prevent seawater backflow. Six submersible pumps then pump the stormwater into Victoria Harbour.
Intercepting drains at Queen’s Road Central help reduce the load on the drainage system. They capture about 30% of surface runoff. This further reduces flood risk. The entire drainage system protects Sheung Wan from rainstorms expected once every 50 years.
The Drainage Services Department carefully considered public interests during design. The Central and Western District Council wanted to preserve sea views. They also desired more open space. The pump house’s size and height were reduced and re-oriented. Stormwater pumps were installed below ground. The area above them became a 320-square-meter Tai Chi exercise area. A 5700-square-meter open space sits atop the underground storage tank. It features a waterfront promenade, plaza, and pet garden. Over 110 trees and 20000 shrubs were planted. The public welcomed this design.
The Sheung Wan Stormwater Pumping Station won the Structural Excellence Award 2010. This award recognized its exceptional structural engineering. It demonstrated that the design was both innovative and effective.
Next time you are in Sheung Wan, remember this pumping station. It protects this historic area from flooding. It blends seamlessly with the urban environment. It provides valuable public space.