Singapore awards 9.8km of sewer extensions 26 Aug 2015

The pipejacking division of Strabag subsidiary Ed Züblin, is awarded major construction in two lots to expand the sewer network in Singapore and carry out preparatory works ahead of new metro excavations.

Contract T3005, 4.2km

Contract T3003, 5.6km

Strabag told TunnelTalk it has procured five new micro TBMs (of diameters 300mm, 600mm, 3,100mm, and 2 x 2,100mm) to complete the excavations, plus four refurbished machines (of diameters 1,200mm, 2,100mm, 3,000mm, and 3,100mm) for a total of nine machines. All are manufactured by Herrenknecht.

Total value of the two lots of the Advanced Sewer Diversion and NEWater Pipe and Effluent Outfall Project, awarded by the Singapore Land Transport Authority, (LTA) is Sing$132 million (US$94 million).

Of the three shortlisted companies for Contract T3003 (Lot 1), Züblin submitted the lowest bid (Sing$53.4 million) at just under half the cost of its nearest rival (KTC Civil Engineering), and less than a third of the cost of the proposal submitted by the highest bidder (Chyee Joo Construction).

T3003 involves the rerouting of existing municipal sewer lines and further expansion of the existing network. Scope of works includes excavation of 57 shafts and installation using the pipejacking method of sewer lines and outfall pipe to a total length of 5.6km to a schedule of 27 months. All prefabricated elements will be manufactured and delivered by the Züblin-owned factory in Malaysia.

Contract T3005, for which Züblin was again the lowest bidder (Sing$78.6 million) out of four companies that were shortlisted, involves preparatory works in eastern Singapore for construction of extensions to the metro, and will further extend the sewer network. Scope of works for this lot includes the excavation of 55 shafts and installation of 4.2km of sewer lines, also using the pipejacking construction method.

The diameters of pipe to be installed range from 30cm to 3.1m, similar to those for the 50km of link tunnels excavated by Züblin (for a contract price of US$385 million) as part of the giant Strategic Tunnel Enhancement Project (STEP) project in Abu Dhabi.

Marianne Gruber for Strabag said: "The first drive for T3003 is scheduled to start in October 2015, with the first drive for T3005 scheduled to begin a month later, in November."