Before the sea link, Mahim Causeway was the only road connecting Mumbai's booming western suburbs to its central business district. Every morning, the causeway choked. Every evening, it choked again. The Western Freeway was proposed to span the entire western coastline, and the Bandra-Worli bridge was conceived as its first phase -- an alternative route across the bay that would bypass the causeway entirely. The foundation stone was laid in 1999. The original plan estimated five years to completion. Instead, the project was swamped by public interest litigations that delayed construction by half a decade, during which the cost ballooned from the initial estimate to roughly 16 billion rupees. The first four of the bridge's eight lanes opened in June 2009; all eight became operational on 24 March 2010.

Building in open sea is difficult. Building in the geologically chaotic seabed of Mahim Bay is something else entirely. Engineers from the Hindustan Construction Company and UK-based project managers Dar Al-Handasah faced foundation conditions that varied wildly -- from highly weathered volcanic material to massive high-strength rock -- sometimes within the footprint of a single pile. The bridge rests on 604 concrete piles driven between 6 and 34 meters into the substrate. Its largest pylons rise 128 meters above pile cap level in a diamond-shaped concrete tower, supporting the deck through four planes of cable stays arranged in a semi-harp pattern. The Bandra channel alone uses 264 cable stays, with lengths ranging from 85 to 250 meters. It was the first infrastructure project in Mumbai to use seismic arresters, rated to withstand earthquakes up to 7.0 on the Richter scale.

What the sea link does well, it does brilliantly. The drive between Bandra and Worli during peak hours dropped from 20-30 minutes to roughly 10. An average of around 32,000 vehicles cross each day, passing through a toll plaza with 16 approach lanes equipped with electronic collection systems. The bridge carries a full intelligent management system: CCTVs, automatic traffic counters, variable message signs, a remote weather station, and emergency telephones connected by fiber-optic cables running the entire 5.6-kilometer span. Mobile explosive scanners check vehicles in under 20 seconds. Inflatable buoys surround each supporting pillar to protect against collisions. At night, energy-saving illumination turns the cable stays into luminous arcs above the dark water -- and every photographer in Mumbai knows exactly where to stand.

The sea link's story is unfinished. Traffic numbers fell over 16 percent in the bridge's first four years, partly because high tolls pushed commuters toward alternative routes, and partly because a bottleneck at the Worli end -- where eight lanes narrow to two -- creates southbound backups during morning rush. Critics note the crumbling road surface that appeared soon after completion. Cyclists have been fined for riding on the bridge, though lawyers argue that bicycles fall outside the Motor Vehicles Act entirely. Plans now call for the sea link to become part of the longer Coastal Road extending north to Kandivali. Whether Mumbai's infrastructure ambitions will outpace its infrastructure problems remains the city's perennial question. For now, the bridge hangs above Mahim Bay, its cables holding fast against the monsoon winds, doing what Mumbai does best: making the imperfect work.