Atal Setu: India's Longest Sea Bridge, MTHL, To Be Unveiled Today; Here Are Some Unique Facts

As the Mumbai Trans Harbour Link (MTHL) prepares to open its gates to the public on 12 January 2024, it signifies a monumental achievement for the nation. Stretching across the waters, this sea bridge, India's longest, promises to reshape Mumbai's traffic dynamics by seamlessly connecting South Mumbai to Navi Mumbai. 

Constructed at a cost of Rs 17,840 crore, the Atal Bihari Vajpayee Sewri-Nhava Sheva Atal Setu, a 21.8 kms bridge, is a six-lane marvel, encompassing a 16.50 kms stretch over the sea. Its anticipated to significantly reduce the commute duration from Navi Mumbai to South Mumbai, bringing it down from nearly two hours to a mere 20-25 minutes.

Engineering marvelThe initial choice of a cable stay bridge was dismissed to preserve the flight paths of flamingos. For the project, special steel sections from Japan were imported. Each section meticulously manufactured, assembled and tested in Japan before shipping to India, ensuring resilience under substantial loads.

Financial collaborations across borders

Japanese banks played a pivotal role in financing the project, contributing around Rs 18,000 crore. The construction process involved various packages, with Japanese contractors such as L&T, IHI, Tata-Daewoo and JFE bringing their expertise to the forefront.

Rigorous testing for resilience

Seismic load tests were conducted using a model to ensure the bridge's ability to withstand earthquakes. It's designed to handle 1.5 times the most intense earthquakes likely in the region and equipped to counter wind speeds up to 150 kph using tuned mass dampers.

Challenges of railway tracks integration

Incorporating railway lines faced challenges due to steep gradients necessitated by the bridge's rise and dip for ship clearance and to avoid flamingo paths.

Environmental commitment

Rs 330 crore was allocated for an extensive environmental management plan, encompassing mangrove plantation, tree relocation and pollution monitoring. The project also involved fisherman compensation policy and a social impact assessment ensuring sustainable development.

Innovative tolling approaches

Toll collection primarily automated at the Chirle end, ensuring uninterrupted traffic flow. A combination of digital payments and traditional cash lanes, with 5-7 per cent of toll still collected in cash.

Costs and toll adjustments

The initially proposed toll of Rs 500 underwent adjustments, with a one-way toll set at Rs 250 and a return toll at Rs 375. Daily and monthly passes offering flexibility for regular commuters are also available.

Safety and security measures

CCTV cameras are installed at every 250 meters, with emergency call boxes and strategically positioned police chowkies for enhanced security. Support vehicles are stationed midway, ensuring a swift response to any incidents. The speed limit is set at 100 kph.

As Mumbai eagerly awaits the inauguration, the MTHL stands not just as a transportation marvel but as a symbol of collaborative engineering brilliance poised to transform the cityscape.