Mumbai Trans Harbour Sea Link: MMRDA launches longest orthotropic steel deck of 180 metres on MTHL

The Mumbai Metropolitan Region Development Authority (MMRDA) on Thursday launched a 180-metre-long orthotropic steel deck (OSD) on the Mumbai Trans Harbour Link (MTHL).

This OSD is the longest one to be launched on MTHL and will give a navigation space of 180 metres to ships passing under the bridge.

Up till now, five OSDs have been launched on the MTHL. The first one was launched on January 3 and was 70-metres long. There will be a total of 70 OSDs on MTHL.

The Orthotropic Steel Deck is a superstructure useful to carry the vehicular load more efficiently among three panes and improve the load-carrying capacity of the bridge as compared to the Concrete Superstructure. OSD Steel Deck Superstructure has lesser self-weight than concrete or composite girders and is an ideal solution considering MTHL site conditions (Navigational Channels, Discharge Channels) and longer pier to pier distances.

The use of conventional concrete decks would have meant building closer foundations for the piers. Moreover, OSD's are also more cost-effective compared to the Cable Stay or Suspension bridges, according to the MMRDA.

The Mumbai Trans Harbour Link is a 22 km long, 6-lane bridge with about 16.5km long over the sea and about 5.5 kms long via duct on land on either side. The Link has interchanges at Sewri in Central Mumbai, Shivaji Nagar at Mumbai Bay and NH-4 B at Chirle, Navi Mumbai.

The sea bridge will be equipped with an intelligent transport system (ITS) and the other amenities required. The traffic conditions on the stretch will be monitored and managed from the traffic control centre with the help of CCTV cameras and related facilities installed.

The smooth execution of construction work of the entire MTHL, has been divided into three packages. Once ready the MTHL will connect South Mumbai to the Navi Mumbai in a mere 25 minutes as compared to the current travel time of 120 minutes. The project cost is pegged at Rs 17,843 crores. About 75 per cent of piers work is complete and the overall project progress achieved is about 67 per cent to date. The expected timeline to complete the project is 2023.