![Photo Photo](/images/categories/infrastructure/2013/12/week1/DrainageC.jpg)
Water works:
Under Secretary for the Environment Christine Loh and Director of Drainage Services Chan Chi-chiu (third from right) officiate at the Aberdeen to Sai Ying Pun sewage tunnel breakthrough ceremony.
Tunnel breakthrough ceremony held
December 02, 2013
Under Secretary for the Environment Christine Loh and Director of Drainage Services Chan Chi-chiu officiated at the Aberdeen to Sai Ying Pun sewage tunnel breakthrough ceremony today.
The tunnel is part of Harbour Area Treatment Scheme Stage 2A.
It collects sewage from preliminary treatment works in Aberdeen, Wah Fu, Cyberport and Sandy Bay, then conveys it to Stonecutters Island Sewage Treatment Works. From there, after further treatment and disinfection, it is discharged in to the sea.
Ms Loh said the tunnel will help improve Victoria Harbour's water quality, adding the Cross Harbour Race has been restored since 2011.
The 7.5km tunnel goes as deep as 120 metres below sea level, equivalent to the height of a 40-storey building.
Mr Chan said the tunnel was built in an area where groundwater was a problem. To tackle the issue, he said technical advice was sought from European experts, and works were undertaken to control groundwater leakage and reduce the risk of subsidence during construction.
The $2.5 billion scheme is due for completion by the end of next year.