Sand dunes have been illegally excavated in Injambakkam, near VGP theme park, despite coastal regulation zone rules prohibiting such excavation. “Since last week, dunes have been removed for at least 100 metres along the beach. I filed a complaint with Neelankarai (J8) police,” said I H Sekar, a local social worker, alleging that the mined sand is being sold for 200 per load, and he faced death threats from miscreants after confronting them.

In May, the National Green Tribunal prohibited CMDA from disturbing dunes on Injambakkam beach, mandating permissions from Union govt or State Coastal Zone Management Authority.

CMDA member secretary Anshul Mishra said the planning agency did not disturb the dunes. “To prevent illegal sand mining, we are planning beach rejuvenation,” he said, adding that CMDA received Blue Flag council approval for five beaches including Injambakkam and Akkarai with a GO expected next week.

“Sand dunes prevent coastal erosion,” said Ramasubramanian R, a coastal systems researcher with MS Swaminathan Research Foundation. There were sand dunes in the centre of the city at least three decades ago. But seawater entered land on Pattinapakkam beach, eroding the coast, thanks to disappearing sand dunes. “The coast along ECR is under threat now. Sand dunes also prevent saline water intrusion in underground aquifers.”

Greater Chennai Corporation maintains city beaches. “I will verify and take further action,” said GCC zonal officer (Sholinganallur) D Rajasekar. In Besant Nagar, GCC has removed encroachments from the Arupadai Veedu Murugan Temple beach since June.