Select language:
Harbour Area Treatment Scheme (HATS); Harbour Area Treatment Scheme (HATS);

HATS Stage 2A, Hong Kong

A major sewerage infrastructure project in Victoria Harbour

Arup has been appointed by the Hong Kong SAR Government’s Drainage Services Department as the Consultant for the Harbour Area Treatment Scheme (HATS) Stage 2A – Upgrading Works for Stonecutters Island Sewage Treatment Works (SCISTW) and eight Preliminary Treatment Works (PTWs) on the Hong Kong Island. 

HATS is one of the largest ever sewerage infrastructure projects in Hong Kong. HATS Stage 1, commissioned in 2001, provides treatment to about 75% of the sewage from urban areas around the Harbour. HATS Stage 2, a two-phase programme, provides additional facilities to convey all remaining sewage from the Harbour area to SCISTW for chemically-enhanced primary treatment (CEPT) and disinfection, and subsequent biological treatment. With a footprint of only 10 hectares, the SCISTW is designed to handle a sewage flow of 2.45 million m³ per day and serve a population of 5.7 million. 

Arup is responsible for the design and construction supervision of the upgrading works of SCISTW and PTWs, responsible for civil, electrical and mechanical, process, environmental, control and automation engineering, as well as the overall project management and implementation of HATS Stage 2A. 

Project Summary

Largest scale sewerage infrastructure projects in Hong Kong.

2.45Mm³The average capacity per day for the treatment plant

5.7millionpeople served by the project

HATS Stage 2A has been completed in 2015, the remaining 25% of sewage generated on the northern and southwestern sides of Hong Kong Island will be collected for CEPT and disinfection before discharge, bringing further improvement to the water quality in Victoria Harbour.

A short film introducing the Harbour area treatment scheme (HATS) stage 2A: the largest ever sewerage infrastructure projects in Hong Kong.
To view this video, you must enable cookies.


  • ICE Awards 2018 – Edmund Hambly Medal

  • The 15th Tien-yow Jeme Civil Engineering Prize

  • Global Water Awards 2016 Wastewater Project of the Year – Distinction Award

  • British Construction Industry Awards 2016 – Highly Commended International Project of the Year