Breakthrough at Hong Kong West Drainage Tunnel (with photos)Construction of Hong Kong West Drainage Tunnel, designed to alleviate flooding in northern Hong Kong Island, entered its final phase when the successful tunnel "breakthrough" at Stubbs Road in Wan Chai was made by two tunnel boring machines (TBM) in January this year.
To mark this milestone, the Secretary for Development, Mrs Carrie Lam, today (February 17) officiated at a Tunnel Breakthrough Ceremony at Stubbs Road, where the two TBMs met.
Mrs Lam said that with the completion of the tunnel in 2012, about 30% of the stormwater from northern Hong Kong Island could be effectively diverted.
"The existing flood protection level in most areas of northern Hong Kong Island will then be able to withstand rainstorms with a return period of 1 in 50 years. The risk of flooding in commercial and residential areas in Central and Western District and Wan Chai District will be greatly alleviated. Traffic disruptions and disturbances to the public caused by flooding will also be minimised.
"The government is implementing various flood prevention and sewerage infrastructure projects with a total cost of $36.6 billion, in order to create a quality living environment in Hong Kong. Other major projects with a total value of $20.6 billion are also under planning. It is expected that these new projects will create 4,500 job vacancies," Mrs Lam said.
The Director of Drainage Services, Mr Chan Chi-chiu, said the $3 billion project was the biggest flood prevention project implemented by the Drainage Services Department so far.
"One of our primary tasks during construction is to minimise the impact on the environment as well as on the daily lives of the public. We adopted the approach of stormwater interception by building a drainage tunnel to reduce the extent of traditional drainage upgrading works that would involve extensive excavation in the urban area. We also used the 'raise boring method' to construct most of the intake drop shafts to contain the construction's impact below ground.
"Over the past years, we have consulted the Wan Chai, Central and Western and Southern District Councils, which have given us their valuable opinions on the project. We are indebted to the public for their understanding and support to the project which is crucial for its smooth implementation for further reduction of the flooding risk in northern Hong Kong Island," he said.
The project - the longest drainage tunnel in Hong Kong - consists of an 11-kilometre-long main drainage tunnel extending from Tai Hang to Cyberport, 34 intakes and eight kilometre-long adits connecting the intakes with the drainage tunnel. The drainage tunnel will intercept stormwater collected from Mid-Levels and discharge it directly into the sea.
To shorten the construction period of the tunnel and to minimise the impact on residents, traffic and the environment, two TBMs have been deployed to operate simultaneously for tunnel excavation from the Eastern end in Tai Hang and the Western end in Cyberport.
Dragages-Nishimatsu Joint Venture is the contractor for design and construction of the Hong Kong West Drainage Tunnel while Ove Arup & Partners Hong Kong Ltd is the supervising consultant. The construction commenced in November 2007, and is expected to be completed in 2012.
For details of the Hong Kong West Drainage Tunnel, please visit www.dsd.gov.hk/others/HKWDT/eng/background.html.
Ends/Thursday, February 17, 2011
Issued at HKT 17:16