BMC plans two excavations at Malabar Hill in Mumbai

The Malabar Hill in Mumbai will soon witness two massive excavation works. One is for a 3.5-km tunnel through the rocky outcrop to carry a six-lane coastal road, and the other for a vast underground chamber that will hold nearly 30 million litres of water. The coastal road's twin tunnels will even pass below the reservoir. The water chamber, planned at a depth of 7 meters (23 feet), is an extension to an existing reservoir underneath a leafy, eight-acre patch. To address concerns about the stability of the hill, an IIT-Bombay expert was tasked to study the impact of construction on its basalt ridges. The report mentioned that the tunnel is 70 meters below the reservoir and enough margin exists to absorb stresses, considering the strength of the rock between the underpass and the reservoir's foundation. To ensure precaution, vibration monitors and tiltmeters are being installed on the 45-odd buildings along the tunnel's alignment between Girgaum Chowpatty and Priyadarshini Park.