The first contract, worth $HK61 million, involves work on approximately 27 km of aged water mains with a diameter ranging from 20 to 250 mm in San Tin and Pak Shek Au. The second contract, worth $HK47 million, involves approximately 13 km of water mains with a diameter ranging from 25 to 450 mm in the Kwai Tsing and Tsing Yi areas.
In view of the heavy traffic in Kwai Tsing, Assistant Director of Water Supplies Ng Chi-ho said approximately 40 per cent of the construction works will adopt No-Dig construction methods to minimise traffic disruption. In the vicinity of the container terminal and critical road junctions, construction works will be carried out at night, during off-peak hours and on Sundays and public holidays.
The contracts are the first two to be awarded under Stage Two of the city-wide water mains program, which aims to replace or rehabilitate approximately 3,000 km of aged water mains in 15 years in order to maintain a reasonable level of services to consumers.
Mr Ng said the comprehensive water mains improvement program would progressively reduce incidents of burst water mains and leakage.
To replace the water mains, the HK Water Supplies Department said it will employ several methods including pipe jacking, pipe ramming and horizontal directional drilling. For pipe rehabilitation, close fit lining, CIPP and pipe bursting will be used.
Stage One work comprises the replacement and rehabilitation of approximately 600 km of water mains, and Phase One and Two of the stage are scheduled for completion in December 2008 and March 2010 respectively. Stage Two will cover approximately 750 km of pipe, with Stage Three covering nearly 800 km of water mains.
Works commenced at the end of January 2007 and are expected to be completed in 2011. The entire program is anticipated for completion before 2015, when future improvement works will be proposed.
To replace the water mains, the HK Water Supplies Department said it will employ several methods including pipe jacking, pipe ramming and horizontal directional drilling.