As part of the program to improve water quality in Narragansett Bay, the Narragansett Bay Commission has issued to CB3A joint-venture notice to proceed with the work on the Pawtucket Tunnel Project. This joint venture comprises CBNA, a US-based subsidiary of Bouygues Travaux Publics, and local civil works contractor Barletta Heavy Division. The contract is worth $479.4 million USD (Bouygues Travaux Publics’ share is $311.5 million).
Located in the Rhode Island Delta, approximately 75 km south of Boston, the Pawtucket Tunnel Project is the first part of Phase 3 of the Bay’s water management modernization program (Phase IIIA). CB3A is responsible for the design and construction of the tunnel and its ancillary structures.
The 3.5 km-long main tunnel will be excavated along the Seekonk River using a tunnel boring machine specially designed to accommodate the varied geology of the route. Its 9-m internal diameter will enable it to collect and store a significant proportion of the region’s rainwater, waste water and industrial water pending treatment by the water treatment plant.
The project also involves the excavation of three main shafts, one of which will serve as a pumping station and supply the existing treatment plant. Four drop shafts will also be built to collect water, as well as their connecting tunnels to the main tunnel.
Carried out in the heart of an urban residential area, the project will be subject to measures designed to protect the environment and minimize the impact of the work on local residents.
CB3A will be supported by engineering company Aecom to carry out the design and will also promote local employment and the integration of local businesses when organizing the work.
The contract is for a period of 48 months.