Mumbai Trans Harbour Link: India's longest sea bridge project explained

With an estimated cost of Rs. 17,843 crore, the MTHL project is managed by the Mumbai Metropolitan Region Development Authority and has neared 97% completion

Last week, the Bharatiya Janata Party (BJP)'s Maharashtra unit announced that the Mumbai Trans Harbour Link (MTHL), dubbed India's longest sea bridge, may be opened to the public on December 25. However, only 97 per cent of the project has been completed, and it is not likely to be done by that time. The project may not be completed until January 2024.

Earlier, the government agency set December 25 as the date of inauguration for the long-awaited bridge that promises to reduce travel time during peak hours by 30-45 minutes. While the inauguration may go forward, the agency implementing the project has stated that work of electrification, erection of poles on the bridge, toll booths and integration of the entire system is yet to be done. Here's a closer look at the MTHL project, what it is, its impact, and its construction.

 

What is the Mumbai Trans Harbour Link (MTHL)?

The Mumbai Trans Harbour Link (MTHL) is a 21.8 km road bridge project that will connect Mumbai and its satellite city, Navi Mumbai. Once completed, it will be the longest sea bridge in India.

Background on the Mumbai Trans Harbour Link

The inception of the Mumbai Trans Harbour Link dates back to 1963, when it was initially proposed as the Uran Bridge. However, it faced numerous setbacks before gaining momentum. The first tangible effort was made in 2006 when IL&FS proposed a Build Own Operate Transfer (BOOT) model. Unfortunately, this attempt was shelved. In 2017, the Maharashtra government decided to entrust the Mumbai Metropolitan Region Development Authority (MMRDA) with the MTHL project. The Engineering – Procurement – Construction (EPC) model was adopted, supported by an official development loan of approximately Rs 18,000 crore from the Japan International Cooperation Agency (JICA).

What areas in Mumbai will be connected by the Mumbai Trans Harbour Link?

Commencing in Sewri, South Mumbai, the bridge traverses Thane Creek, north of Elephant Island, concluding at Chirle village near Nhava Sheva. The bridge is strategically positioned to link key areas such as the proposed Navi Mumbai International Airport, JNPT Port, Mumbai–Pune Expressway, and the Mumbai–Goa Highway.

There are strategic interchanges at Sewri, Shivaji-Nagar, SH-54 in Jasai, and Chirle on NH-348 to ensure seamless connectivity. These interchanges are pivotal for optimising traffic flow and accessibility.

The MTHL will also connect Mumbai and Navi Mumbai to the Pune and South Indian expressways. Moreover, its proximity to the upcoming Navi Mumbai International Airport ensures access to the airport from various parts of the city.

Length and structure of the Mumbai Trans Harbour Link

The MTHL comprises a 16.50-km sea link and a 5.5-km land portion. The sea link is a 6-lane highway (3+3 lane) with an additional emergency lane on both sides.

It also incorporates seven orthotropic steel deck (OSD) spans, ranging from 90m to 180m, a first-of-its-kind application in India. The OSD is a lighter and more flexible solution than its concrete counterpart. It reduces assembly time, allows rapid replacement or rehabilitation of bridges, and allows the deck to bear vehicular loads directly.

What is the cost of the Mumbai Trans Harbour Link project?

The Mumbai Metropolitan Region Development Authority (MMRDA) manages the MTHL construction, which is estimated to cost Rs 17,843 crore. As of November 2023, according to MMRDA, 91 per cent of the estimated cost had been spent on the project.

Who is implementing the MTHL project?

The MTHL project comes under the Mumbai Metropolitan Region Development Authority (MMRDA). A consortium comprising AECOM Asia Company Ltd., PADECO Co Ltd, Dar Al-Handasah, and TY Lin International have served as general consultants. The project was built in four stages or packages. This included three civil works packages and one package for Intelligent Transport System (ITS), automated toll collection system, and electrical works. The packages are as follows:

Package 1: Bridge spanning across Thane Creek and Sewri Interchange (10.38 km) - inter-tidal and marine construction.
Contractor: L&T Ltd-IHI Infrastructure Systems Ltd Consortium (Rs 7,637 cr)

Package 2: Bridge portion across Thane Creek and the Shivaji Nagar interchange (7.807 km) marine construction.

Contractor: DAEWOO Engineering & Construction Company Ltd - Tata Projects Ltd JV (Rs 5,612 cr)

Package 3: Viaducts and interchanges that connect MTHL with State Highways 52 and 54 and National Highway 4B at Chirle (3.613 km) construction on land.
Contractor: L&T Ltd (Rs 1,013 cr)

Package 4: Intelligent Transport Systems (ITS), including toll and transport management system and equipment installation

Contractor: STRABAG Infrastructure & Safety Solutions GmbH & STRABAG AG (Rs 427 cr)

Why is the Mumbai Trans Harbour Link important?

Mumbai, known for its dense population, grapples with congestion in local trains and public transport. The MTHL is a transformative solution anticipated to significantly alleviate traffic on existing entry points to Mumbai, enhancing overall connectivity. With the upcoming Navi Mumbai airport in Panvel, MTHL promises seamless connectivity from the mainland. For daily commuters between Navi Mumbai and Mumbai, the bridge is a time-saving boon that can reduce travel time by 30-45 minutes during peak traffic hours.

Mumbai and Navi Mumbai currently have only two road connectivity options. The MTHL is also likely to bolster connectivity between Mumbai Port Trust (MbPT) and Jawaharlal Nehru Port Trust (JNPT) and stimulate urban and industrial development.

Project Progress

When packages 1 and 2 commenced in 2018, the MMRDA estimated the project would be concluded by September 2023. Last week, the BJP Maharashtra unit announced the bridge's inauguration on December 25, 2023. However, MMRDA has stated that the bridge is 97 per cent complete and is not likely to be finished until January 2024. The Covid-19 pandemic partially delayed work on the project. Despite this, the bridge may be open to the public in the last week of the calendar year.

The Maharashtra unit of the Bharatiya Janata Party (BJP) said on X (formerly Twitter) that the "Atal Bihari Vajpayee Sea Link" would be inaugurated on December 25 this year, on the birth anniversary of the late prime minister after whom it is to be named.

While the BJP has announced the inauguration date, the Maharashtra government has not stated anything yet.