AECOM is the lead general consultant for the joint venture of AECOM, PADECO, Dar Al-Handasah and TY Lin. Our design and supervision consultancy is helping to building a 13.6-mile long (22-kilometres (km)) six-lane viaduct and freeway grade road bridge connecting Mumbai and Navi-Mumbai across the Mumbai Harbour. The project will include approach roads, viaducts, large navigational spans and interchanges. When completed, it will be the longest sea bridge in India.

The bridge will begin in Sewri, South Mumbai and cross Thane Creek, north of Elephanta Island. It will terminate at Chirle village, near Nhava Sheva. The road will be linked to the Mumbai Pune Expressway in the east, and to the proposed Western Freeway in the west. 

MTHL is seen as an important project to decongest the city, especially south Mumbai. It is expected to reduce vehicular congestion in several areas, especially the arterial roads connecting south Mumbai with the eastern or central suburbs and the Sion-Panvel expressway. Vehicles going to Navi Mumbai, Pune, Konkan and Goa will be able to cut their journey by directly going to Raigad through this sea link.