Rs 7,000-crore Mumbai-Pune Expressway Missing Link hit by landslide; MSRDC defends infrastructure failure, calls it an 'act of God'

Barely nine weeks after Chief Minister Devendra Fadnavis inaugurated the Rs 6,695-crore Mumbai-Pune Expressway Missing Link as a permanent solution to the expressway's biggest traffic bottleneck, a monsoon-triggered landslide has partially shut the corridor, forcing traffic back onto the old Mumbai-Pune Highway it was built to bypass.

The incident marks the first major monsoon test for one of Maharashtra's most ambitious infrastructure projects, raising questions about the readiness of a corridor that was projected as a safer, faster and more reliable alternative to the accident-prone Khandala ghat section.

What is the Missing Link?

The Missing Link is a 13.3-km stretch built to bypass the 19.8-km Khandala ghat section between Khopoli and Sinhgad Institute. For years, traffic on the Mumbai-Pune Expressway was forced to pass through this six-lane stretch, negotiating steep gradients, hairpin bends and sharp curves that frequently witnessed traffic snarls and accidents.

The new alignment shortened the journey by nearly 6 km, reducing travel time between Mumbai and Pune by 20 to 30 minutes, while allowing vehicles to travel at speeds of up to 100 kmph.

Why was it considered an engineering marvel?

Spread across 13.3 km, the Missing Link comprises two twin tunnels measuring 1.6 km and 8.9 km, two high-speed viaducts and a 183-metre cable-stayed bridge soaring above Tiger Valley, making it the tallest bridge of its kind in the country.

The 8.9-km main tunnel, excavated nearly 180 metres below Lonavala Lake using the New Austrian Tunnelling Method, is among the widest road tunnels in the world. Engineers also built temporary access passages through the Sahyadri hills during construction. Designed to withstand high winds, dense fog and intense monsoon rainfall, the project took nearly three decades to become a reality.

Why did it take so long?

The need for an alternative to the accident-prone ghat section was first identified by RITES in 1995, even before the Mumbai-Pune Expressway was built.

The Maharashtra Cabinet approved the project in 2017, construction began in 2019, but the work was delayed by the Covid-19 pandemic, difficult geological conditions and the engineering challenges of tunnelling through the Western Ghats.

At its inauguration on May 1, Devendra Fadnavis described the Missing Link as Maharashtra's new "connecting link", while the Maharashtra State Road Development Corporation (MSRDC) projected it as a permanent solution to congestion and accidents on the ghat section. MSRDC Managing Director Anilkumar Gaikwad had said the project would make travel between Mumbai and Pune "quicker and more reliable" by eliminating one of the busiest chokepoints on the expressway.

What happened on Monday?

The Missing Link suffered its first major disruption barely nine weeks after opening to traffic, after a landslide and damage to a retaining wall forced authorities to suspend vehicular movement on part of the stretch. The landslide also led to a heavy flow of water onto the Pune-to-Mumbai carriageway.

According to the State Highway Police, the incident occurred in the early hours of Monday after continuous heavy rainfall. Officials said the landslide took place near the exit of the first tunnel on the Pune-to-Mumbai carriageway, damaging a retaining wall and making the route unsafe for traffic.

The Pune-to-Mumbai carriageway was immediately closed. Authorities initially suspended traffic in both directions before reopening the Mumbai-to-Pune carriageway around 10 am. However, the Pune-to-Mumbai corridor remained shut. Since both the Missing Link and the adjoining flyover were closed for Mumbai-bound traffic, vehicles from Pune were diverted via the old Mumbai-Pune Highway (NH-48), with traffic being restored in phases.

The disruption came at a time when the old Mumbai-Pune Highway was also affected after a tree collapsed onto a power line, while heavy rainfall caused waterlogging at several locations. With both routes hit simultaneously, authorities urged motorists to postpone non-essential travel between Pune and Mumbai and follow official traffic advisories.

The closure comes barely nine weeks after the project was inaugurated as the biggest upgrade to the region's road infrastructure since the Mumbai-Pune Expressway opened in 2002.

Ironically, the project conceived to free motorists from monsoon disruptions on the old ghat section ended up sending them back to the very route it was designed to replace during its first rainy season. The incident also highlights the continuing challenge of building major transport infrastructure through the rain-prone Sahyadri ranges, where unstable slopes and heavy rainfall continue to test even the state's most ambitious engineering projects.

What did the road authority say?

The Maharashtra State Road Development Corporation (MSRDC) attributed the incident to nature, describing it as an "act of God" rather than a construction flaw.

MSRDC Vice Chairman Anilkumar Gaikwad said relentless rainfall caused large boulders to slide down the hillside, blocking the entrance of Tunnel 2.

"The tunnel structure has not been affected, but the false frame — an external structure built at the tunnel entrance — has been damaged," he said.

Another MSRDC official said rockfall mitigation measures, vetted by IIT Bombay, had been installed, including rock-bolting mesh up to a height of 15 metres above the tunnel. However, the falling boulders came from nearly 150 metres above the protected area.

"Such heavy rainfall is akin to an act of God, with little that can be done to prevent it," the official said.