SECOND TRANCHE of tunnelling work on Hong Kong's troubled strategic sewage disposal scheme has been awarded to a joint venture between Kvarner Cementation and its Hong Kong subsidiary Gammon Construction.
The HK$600M (£48M) contract is to construct two deep hard rock tunnels through granite, both 143m below sea level.
Two hard rock tunnel boring machines will be used for the excavation of the 3.5km long 3.3m diameter tunnel from Kwun Tong to To Kwa Wan and the 5.5km long 4.3m diameter tunnel from To Kwa Wan to Stonecutters Island. Both tunnels will have a segmental lining and construction is expected to take two years to complete.
Tunnelling work for the SSDS, originally scheduled for completion in May last year, was initially let as two contracts to a Campenon Bernard/Maeda joint venture in early 1995. But the contractor stopped work on the HK$1.3bn scheme in the middle of 1996, claiming that high water inflow was threatening safety.
Client Hong Kong Drainage Services Department repossessed the sites from CBM in November 1996, and retained the contractor's plant.