Carbon dating of ram setu
The channel is expected to cut over 400 km (nearly 30 hours of shipping time) off the voyage around the island of Sri Lanka.
This proposed channel's current alignment requires dredging through Adam's Bridge.
The lack of comprehensive field studies explains many of the uncertainties regarding the nature and origin of Adam's Bridge, which mostly consists of a series of parallel ledges of sandstone and conglomerates that are hard at the surface and grow coarse and soft as they descend to sandy banks. One account mentions that this landform was formerly the world's largest tombolo that split into a chain of shoals by a slight rise in mean sea level a few thousand years ago.
Based on satellite remote sensing data, but without actual field verification, the Marine and Water Resources Group of the Space Application Centre (SAC) of the Indian Space Research Organisation (ISRO) concludes that Adam's Bridge comprises 103 small patch reefs lying in a linear pattern.
The coral reefs are variously designated by other studies as ribbon and atoll reefs.
The bridge is 48 km (30 mi) long and separates the Gulf of Mannar (south-west) from the Palk Strait (northeast).
Some of the regions are dry and the sea in the area rarely exceeds 1 metre (3 ft) in depth, thus hindering navigation.
Opposition parties demanded implementation of the Sethusamudram canal project using one of the five alternative alignments considered earlier by the Government, without damaging the structure of Adam's Bridge.
The government of India constituted nine committees before independence, and five committees since then, to suggest alignments for a Sethusamudram canal project.