UK contractor Balfour Beatty in JV with US tunnelling partner ML Shank has picked up the major contract to construct 5kms of 9m diameter tunnel and associated works on the Narragansett Bay combined sewage overflow alleviation scheme under Providence City, Rhode Island. Notice to proceed was scheduled for the 30th January.
At US$163.5M, the JV submitted the lowest of three bids beating off competition from JF Shea/Frontier Kemper JV and Modern Continental.
The JV will bore the tunnel with a 9m+ TBM through a variety of Metasedimentary rocks. Although at this stage no machine manufacturer has been chosen, a spokesman for the JV told T&TI that it envisaged acquiring the TBM over the next two – three months with boring expected to start at the beginning of 2003.
The lining will initially comprise pre-cast segments as support with a second pass in-situ concrete final lining bringing the final i.d. to around 8m. Also included is the drill and blast construction of an approximate 17m high x 18m wide x 36m long pumping station cavern, 18 access, ventilation and drop shafts up to 85m deep by 2.7-8m diameter and a number of deaeration chambers and adits.
The project’s Program Manager is the Louis Berger Group with design engineering of the tunnel in the hands of the Jacobs/Svedrup JV.
The tunnel is the largest of several contracts on the first phase of a 22-year programme designed to control CSO’s into the waterways of the Narragansett Bay Commission’s Providence City service area. Phase 1 is scheduled for completion in 70 months.
Related Files
Figure 1: The tunnel alignment
