On 6 February 2003, a 3.28m diameter Lovat TBM was launched on a 5.5km long sewer tunnel in Singapore, following a ceremony on 24 January. The client, The Public Utilities Board, Singapore, awarded the US$2407M Kim Chuan Link sewer tunnel construction contract to the Tiong Seng/Dong-Ah consortium. Lovat was commissioned to supply components and engineering for the RMP129SE Series 14900 TBM (owned by Dong-Ah). The machine will bore 5,450m of tunnel, through the familiar Singapore geology of marine clay, silty clay, sandy clay, silty sand, and sand. Constructed entirely below the water table, the tunnel alignment run at depths ranging from 17m to 21m, with water pressure up to 1.5 bar found at the invert. The machine will erect a single pass lining, consisting of prefabricated-reinforced concrete segments (five and a key), leaving the tunnel with an internal diameter of 2.9m and an excavation diameter of 3.2m. The tunnel is being constructed as part of the Lion State’s US$5bn deep tunnel sewerage scheme. The TBM launch was originally delayed until 6 February so that the Chinese New Year could be celebrated. Tunnelling is scheduled to take 24 months.
