Bandra Worli Sea Link Case Study: Cable-Stayed Spans, Towers and Construction

The Bandra Worli Sea Link carries eight lanes of traffic across the sea between Bandra and Worli in Mumbai, on twin precast concrete viaducts with two cable-stayed bridges where the deck crosses the navigation channels. It was commissioned by the Maharashtra State Road Development Corporation (MSRDC), designed in its final form by Dar Consultants and built by Hindustan Construction Company (HCC). The first carriageway opened on 30 June 2009 and the second on 24 March 2010. This case study explains its towers, stays, sea foundations and precast construction, and why it took a decade and more than twice its first estimate.

Bandra Worli Sea Link: the facts

Official name: Rajiv Gandhi Sea Link.

Client and owner: Maharashtra State Road Development Corporation Ltd (MSRDC), a Government of Maharashtra company.

Design and supervision: Sverdrup was the first design and project management consultant; Dar Consultants (UK) and Dar Consultants (India) took over in 2003 to design, proof-check and supervise the works. No architect is credited in the sources we found.

Contractor: HCC for Package IV, the sea bridge. domain-b names China Harbour Engineering as HCC's foreign partner. Technical consultant to HCC: VSL Singapore.

Location: from the Mahim intersection at Bandra to Khan Abdul Gaffar Khan Road at Worli, Mumbai.

Years: project taken up in 1999; Package IV awarded to HCC in September 2000; full-scale work from December 2004; southbound carriageway opened 30 June 2009, northbound 24 March 2010.

Type: twin four-lane carriageways on precast segmental concrete box girders, with a cable-stayed bridge over the Bandra channel and another over the Worli channel.

Size: 5.6 km as MSRDC and the press give it; 4.7 km for the bridge across the open sea in HCC's account. Bandra cable-stayed bridge 600 m; Worli cable-stayed bridge 350 m; Bandra tower 128 m above pile cap (124 m and 126 m are also quoted).

Cost: estimated at ₹665.81 crore in July 1999 and revised to ₹1,306.25 crore in August 2004 (CAG). Reports at the opening in June 2009 put it at over ₹1,600 crore.

Status: in use as a tolled road bridge run by MSRDC.

Where to see the real drawings. We could not find MSRDC's or HCC's drawings online. The most detailed public account is the November 2009 Coordinates feature, with HCC's project manager S Diwanji and principal surveyor Len Gower, and construction photographs. Our guide on how to do an architecture case study shows how to lay these out as sheets.

The brief and the client

The sea link was planned as the first phase of a Western Freeway along Mumbai's west coast, to ease traffic at the Mahim, Dadar and Worli junctions. The Comptroller and Auditor General's 2007 audit of MSRDC records that the corporation took it up in 1999 at an estimated ₹665.81 crore, for completion by March 2003, and split it into five packages: flyovers and an interchange at the two ends and the Bandra approach road (Packages I to III, finished by February 2003), the sea bridge itself (Package IV) and a road improvement later dropped from the scope (CAG, Audit Report (Commercial) 2006-07, chapter 2).

The CAG notes that it was planned as a "self earning project", repaid from tolls, so every month of delay also deferred the income meant to repay the loans.

Site and context: building in the open sea

The bridge runs offshore, parallel to the coast, rather than across a narrow creek. HCC's engineers told Coordinates that the ground ranged from basalts, volcanic tuffs and breccias to weathered rock, calcareous sandstone and up to 9 m of marine clayey silt, and that 191 bores were drilled in the sea to map it (Coordinates, November 2009).

Two other site conditions shaped the job. The Maritime Board does not allow marine traffic in the monsoon, so work at sea stopped from mid-May until October, leaving "only seven months in a year" for marine work, in Diwanji's words. The CAG also records that the first environmental clearance, in January 1999, limited reclamation to 4.7 hectares; MSRDC reclaimed more, the state stayed the work in January 2000 after protests by environmental groups, and the Ministry of Environment and Forests cleared 27 hectares in April 2000. The stoppage lasted 105 days.

In June 2000, Bridge Design & Engineering reported that the project had been held up by environmentalists, fishermen and Bandra residents before the environment ministry cleared it.

The Bandra Worli Sea Link at sunset seen from a rocky shore at low tide: a long concrete deck on a row of twin piers runs towards two tall cable-stayed towers whose fans of stays glow in the low light, with the high-rise skyline of Mumbai in the haze behind — The two Bandra channel towers, one for each carriageway, with the precast approach viaduct on piers about 50 m apart in front. Photo: Rutiknatekar, CC BY-SA 4.0, via Wikimedia Commons

Bandra Worli Sea Link design: concept and the 2003 redesign

The bridge that was built is not the bridge that was first designed. The CAG gives the sequence:

September 1998: a cable-stayed design approved for the Bandra channel.
June 2000: eight lanes settled, after the first consultant, Sverdrup, had been asked to price six-lane and four-lane options.
December 2001: an arch bridge approved for the Worli channel.
January 2003: the new consultant, Dar, proposed two separate four-lane carriageways, twin towers at Bandra and a cable-stayed bridge at Worli, as "a precondition to take over the consultancy work of the main bridge", in the CAG's words.
August 2004: the changes approved, at ₹20 crore for the twin towers and ₹50 crore for the Worli cable-stayed bridge.

MSRDC told the auditors the changes met requirements of the fishing community and would bring toll revenue sooner; the CAG replied that the fishermen's presence was known when the arch was approved, and that the stated ground for the Worli change was "aesthetics". In June 2009, Rahul Bhatia of Open reported that a Dar spokesperson, asked why the change was needed, replied: "Ask the MSRDC."

The built scheme is two parallel, independent bridges of four lanes each, so each carriageway at Bandra has its own tower. The two cable-stayed bridges mark the two channels; everything else is a repetitive viaduct.

Layout and spans: the plan of a sea bridge

A bridge's "plan" is its sequence of spans. HCC's account and an IIT Delhi Virtual Labs page describe three parts: a precast segmental approach from the north, the two cable-stayed bridges, and a precast segmental approach to the south (Virtual Labs, IIT Delhi).

Approach viaducts: continuous concrete box girders on piers typically 50 m apart, up to 25 m high in open sea.
Bandra channel bridge: 600 m between expansion joints, in spans of 50 m, 250 m, 250 m and 50 m.
Worli channel bridge: 350 m, in spans of 50 m, 50 m, 150 m, 50 m and 50 m.

Schematic of the Bandra Worli Sea Link in three parts: a north-to-south strip from Bandra to Worli showing precast approach viaducts on piers with the tall Bandra channel cable-stayed bridge and the smaller twin-towered Worli channel bridge; an elevation of the Bandra bridge with spans of 50, 250, 250 and 50 m, a central tower 128 m above pile cap whose legs form a diamond below a single upper shaft, and a semi-harp fan of stays; and an elevation of the Worli bridge with spans of 50, 50, 150, 50 and 50 m and two 55 m towers — The two cable-stayed bridges are short stretches of a long precast viaduct; their span lengths and tower heights come from HCC's engineers. Diagram: MOA

Sources differ on length. HCC's team described "a 4.7 km, twin, 4-lane independent carriageway bridge across the open sea", while MSRDC's chief engineer S M Sabnis spoke of the "5.6 kilometre sea link" at the second opening (IANS, 24 March 2010).

Section and structure: towers, stays and deck

The Bandra towers

Coordinates describes the Bandra tower as having "an overall height of 128 meters" above pile cap, an "inverted 'Y' shape with the inclined legs oriented along the axis of the bridge", and also as "diamond shaped". Seen from the side, the legs open into a diamond around deck level and close into a single upper shaft that holds the stays. Len Gower, in the same article, gives 124 m for the tallest tower, P19, and Engineers Journal (2020) gives 126 m. No source we found explains the difference.

The towers were cast in place with climbing formwork, to within ±5 mm, HCC says.

Stays

The Bandra bridge has 264 stays in four planes in a semi-harp arrangement, from about 85 m to nearly 250 m long; the Worli bridge has 160, from about 30 m long. In both, stays are anchored every 6 m along the deck. Each is a bundle of 61 to 121 wires of 7 mm, sheathed in HDPE, supplied by Shanghai Pujiang. The Worli towers are 55 m high and I-shaped.

Deck

The superstructure is "twin precast concrete box girders with a fish belly cross sectional shape" on the cable-stayed bridges, and triple-cell precast box girders on the approaches, in M60 concrete. Because the carriageways are separate structures, each could open on its own: southbound in June 2009, northbound in March 2010, when Sabnis said head-on traffic would be "eliminated" (IANS).

Bandra Worli Sea Link foundation: piles in the sea

According to Coordinates, the bridge stands on 604 drilled shafts, 6 m to 34 m long: 120 of 2,000 mm diameter under the cable-stayed bridges and 484 of 1,500 mm under the approaches. The main tower foundations use 2 m shafts 25 m long. HCC built the pile caps inside cofferdams, using a tremie concrete seal so that the "six-meter deep foundation" could be cast in the dry.

The piles were proof-tested with Osterberg cells, sacrificial hydraulic jacks cast into the pile, to loads of up to 9,600 tonnes. Coordinates calls this the first use of the method in India.

Materials and construction: how it was built

Three construction methods of the Bandra Worli Sea Link: a cofferdam in the sea with a tremie seal and a pile cap cast in the dry on drilled shafts that pass through marine silt into basalt and tuff, with notes on 604 shafts of 2.0 m and 1.5 m diameter and Osterberg cell tests up to 9,600 t; a 112 m launching truss holding fifteen precast segments of a 50 m approach span between two piers; and a tower with a pier table and deck segments added in pairs on both sides, each pair held by new stays — Foundations, approach spans and cable-stayed decks were each built a different way, as HCC's engineers described them in 2009. Diagram: MOA

The precast yard

Almost the whole deck was cast on land. The casting yard sat on reclaimed ground with a bearing capacity of "less than 2 T/Sqm", so HCC dug out about 2.5 m and rebuilt the base before casting began. The yard produced 2,342 segments, each 110 to 140 tonnes and 3.0 to 3.2 m long, with storage for about 470 stacked three high.

Approach spans: span by span

HCC built two launching trusses, each 112 m long. A typical 50 m span is 15 field segments plus a pier segment; the truss holds a whole span between two piers until it is complete, then moves on. Coordinates says these were "the heaviest spans in the country to be built with span-by-span method", at about 1,800 tonnes a span on average and 2,000 tonnes at most. To move the trusses about 600 m from the Bandra side to the Worli side, HCC brought the floating crane Asian Hercules from Singapore in October 2006, saving what the article says would have been a year.

Cable-stayed spans: balanced cantilever

The cable-stayed decks were built by balanced cantilever. Pier-table segments were lifted onto the towers first; then segments were added in pairs on either side, dry-matched, glued with epoxy and temporarily stressed before each new pair of stays took the load. The free cantilevers reached 215 m at Bandra and 73 m at Worli. After closure, the stay forces were fine-tuned for the finished loads.

Readers who build near the sea will recognise the problem the concrete had to solve; our guide to building a house near the sea in India covers salt and corrosion at house scale.

Delays and construction cost

Timeline from 1998 to 2010 with twelve numbered events: Bandra bridge approved as cable-stayed in September 1998, the July 1999 estimate of Rs 665.81 crore, the 2000 stay on work until reclamation was cleared, Package IV awarded to HCC in September 2000, an arch bridge approved for Worli in December 2001, Dar's January 2003 redesign, an 18-month work stoppage from April 2003, the August 2004 revision to Rs 1,306.25 crore, full-scale work from December 2004, the floating crane in November 2006, 38.35 per cent done by June 2007, and openings in June 2009 and March 2010; bars compare the three cost figures — Most of the delay came between 2000 and 2004, when the design was changed and work stopped; the costs are those stated at each stage. Diagram: MOA

Package IV was awarded in September 2000, but in Coordinates' account "in right earnest the work started in December 2004". The CAG explains the gap. HCC objected to the appointment of the new consultant without its consent and stopped work for 18 months, from April 2003 to September 2004, until talks held on the Chief Minister's direction in July 2004. By June 2007, only 38.35 per cent of Package IV was complete and ₹683.75 crore had been spent.

The official cost figures are the CAG's: ₹665.81 crore in July 1999, revised to ₹1,306.25 crore in August 2004. Of the ₹640 crore increase, the CAG attributes ₹230 crore to interest during construction, ₹213 crore to escalation and extra work, ₹125 crore to contractor claims and ₹70 crore to the design changes. We did not find an official final figure. At the opening, domain-b reported that the cost had "risen over six-fold to Rs1600 crore" (the same piece also gives ₹1,684 crore), and Open put it at over ₹1,800 crore.

Reception: what critics, users and the auditors said

The auditors: the CAG found the process for selecting the first consultant "defective", noted that Dar was chosen "despite a poor ranking at the initial evaluation stage", and criticised the late design changes.
Environmental concerns: the CAG cites experts, including the Indian People's Tribunal on Environment and Human Rights (July 2001), who argued that reclamation at the mouth of Mahim creek could affect the flow of floodwater and the Mithi river, and notes that MSRDC had not addressed these issues.
Architects: in Open, Rahul More of Opolis Architects said such projects were needed, "but the problem is that there's no equal distribution of traffic".
The builder: HCC lists the bridge among its milestones as "India's First and Longest Open Sea Cable Stayed Bridge" (HCC, About HCC). That is the company's own description.

For comparison with other long bridges, see our Akashi Kaikyo Bridge case study and our Millau Viaduct case study, where an engineer and an architect shared the design.

What designers in India can take from it

These are our reading of the sources, not claims made by the designers.

Settle the big decisions before the contract. Lanes, towers and the Worli bridge type all changed after the contractor was appointed, and the CAG ties much of the overrun to those changes.
Repetition is what makes a long structure buildable. Over 2,300 precast segments and two launching trusses did most of the work; the 50 m viaduct module, not the towers, is the real design.
Plan for the season. Losing the sea from mid-May to October every year set the pace of the whole project.
Make the landmark where it does a job. The tall towers stand only where the channels need long spans, a useful way to read infrastructure in a thesis; our B.Arch thesis topics list has related typologies.

Visiting the Bandra Worli Sea Link

The sea link is a tolled road bridge run by MSRDC, and we found no official visitor page. It can be crossed by road under the rules and tolls posted at the plazas; the structure reads best from the shore, where viaduct, piers and towers are seen together, as in the photograph above.

Planning a project that needs a careful structure from day one? Find an architect on MOA.

FAQ

Who designed the Bandra Worli Sea Link?

The client was MSRDC. Its first consultant was Sverdrup; from 2003, Dar Consultants (UK and India) were engaged to design, proof-check and supervise the works, and they introduced the twin carriageways, twin Bandra towers and the cable-stayed Worli bridge. HCC built it. The sources we found do not credit an architect.

Which company built the Bandra Worli Sea Link?

Hindustan Construction Company (HCC) built the main sea bridge, Package IV, with VSL Singapore as its technical consultant. domain-b reported China Harbour Engineering as HCC's foreign partner.

When was the Bandra Worli Sea Link built?

Package IV was awarded in September 2000, but full-scale work began in December 2004. The southbound carriageway opened on 30 June 2009 and the northbound on 24 March 2010.

What was the construction cost of the Bandra Worli Sea Link?

The CAG gives ₹665.81 crore as the July 1999 estimate and ₹1,306.25 crore as the August 2004 revision. Reports at the June 2009 opening said over ₹1,600 crore. We did not find an official final cost.

How long and how high is the Bandra Worli Sea Link?

It is usually given as 5.6 km long; HCC's engineers gave 4.7 km for the bridge across the open sea. The Bandra tower is 128 m above pile cap by HCC's project description, with 124 m and 126 m also quoted.

What kind of foundation does it have?

604 drilled shafts, 6 m to 34 m long, of 2.0 m diameter under the cable-stayed bridges and 1.5 m under the approaches, with pile caps cast inside cofferdams.

Sources

Comptroller and Auditor General of India: Audit Report (Commercial) for the year ended 31 March 2007, Government of Maharashtra, chapter 2.1, Bandra-Worli Sea Link Project: packages, dates, consultants, design changes, costs, environmental clearances (accessed 11 Nov 2026)
Coordinates: Making of Bandra-Worli Sea Link, November 2009, with S Diwanji, Len Gower and Rakesh Kaul: spans, towers, stays, foundations, precast yard, launching trusses, construction sequence (accessed 11 Nov 2026)
Open: Rahul Bhatia, At Long Last, 19 June 2009: Sverdrup and Dar, redesign, comments by architects and the consultant (accessed 11 Nov 2026)
domain-b: Bandra-Worli Sea Link: cost rose 6-fold to Rs1,600 crore, 29 June 2009: cost at opening, Dar Consultants, HCC and partner (accessed 11 Nov 2026)
domain-b: Bandra-Worli Sea Link sets another landmark for Mumbai, 30 June 2009: designed by Dar Consultants UK, built by HCC, 5.6 km (accessed 11 Nov 2026)
IANS via TwoCircles.net: Mumbai sea link second carriageway opens, 24 March 2010: second opening, MSRDC chief engineer's remarks (accessed 11 Nov 2026)
Bridge Design & Engineering: Bandra-Worli gets go-ahead, June 2000: early opposition and clearance (accessed 11 Nov 2026)
Virtual Labs, IIT Delhi: Dynamics of Bandra Worli Sea Link Bridge: span arrangement and deck (accessed 11 Nov 2026)
Engineers Journal (Engineers Ireland): Unique engineering behind the Bandra-Worli Sea Link bridge, Trevor English, 7 September 2020: alternative tower height (accessed 11 Nov 2026)
Hindustan Construction Company: About HCC, milestones (accessed 11 Nov 2026)
Hindustan Construction Company: Mumbai Coastal Road Project, 3 October 2018 (accessed 11 Nov 2026)
Wikimedia Commons: Copyright rules by territory: India (freedom of panorama, section 52 of the Copyright Act 1957) (accessed 11 Nov 2026)