Harbour Area Treatment Scheme - PTW Drop Shafts & Scum Chambers
Hong Kong Island, Hong Kong

The Harbour Area Treatment Scheme - PTW Drop Shafts & Scum Chambers Shaft Sites project involves the construction of four PTW dropshafts and scum chambers:

Aberdeen PTW Dropshaft & Scum Chamber 
Overall Depth: 9.20 m
Wah Fu PTW Dropshaft & Scum Chamber
⁠Overall Depth: 22.5 0m
⁠Cyberport PTW Dropshaft & Scum Chamber
⁠Overall Depth: 17.80 m
⁠Sandy Bay PTW Dropshaft & Scum Chamber
Overall Depth: 18.80 m

From July to October 2014, the project involved concrete lining of pre-excavated shafts, each with a uniquely designed scum chamber. The Wah Fu shaft features an elliptical design with a lining size of 7 m by 5 m, while the other shafts are circular with a diameter of 8 m.

Executed with a focus on efficiency and safety, the project ensured rapid construction and minimal disruption. Optimized dimensions facilitated easy operation, prioritizing worker safety throughout the process. Overall, the Shaft Sites project significantly enhances the area's wastewater management infrastructure.