Work to widen the stretch of East Coast Road (ECR) between Mamallapuram and Marakkanam is expected to be completed by March 2027. Around 75% of the four-laning project, for a length of 62 km at a cost of around ₹3,000 crore, has been constructed by the National Highways Authority of India (NHAI). 

On completion, the road will have eight lanes in all, with two service lanes on either side that would ideally be used by local traffic. The work is being carried out in two sections. 

Meanwhile, on Tuesday, the NHAI began a drive to plant tree saplings as part of a special campaign 6.0 under the Swachhata Hi Seva (SHS)-2026. The team, led by Pankaj Asati, Regional Officer, Chennai, planted saplings near Mamallapuram along with students from Guru Shree Shantivijai Jain Arts and Science College.

The Forest Department will plant 4,000 saplings, in addition to those planned as replacements for the 7,500 trees removed to make way for the road. A release said that over ₹5.3 crore has been deposited to plant 7,50,000 saplings.