CHENNAI: A stretch of the Ennore Expressway in north Chennai was closed to traffic on Tuesday after high waves driven by Cyclone Arnab overtopped the shoreline embankment and spilled onto the road. Four coastal districts and the Greater Chennai Corporation (GCC) were put on heightened alert.
The measures announced by the State Emergency Operations Centre (SEOC) followed India Meteorological Department (IMD) warnings of rough seas and high waves along the Tamil Nadu coast.
Additional Chief Secretary and Commissioner of Revenue Administration and Disaster Management B Chandramohan said precautionary measures were being taken along the coast, including in Mahabalipuram, Villupuram and Cuddalore, with field officials closely monitoring the situation.
In north Chennai, rough seas battered the coast ahead of Cyclone Arnab’s expected landfall on the Andhra Pradesh coast between 2 am and 4 am on Wednesday. Dozens of vehicles were knocked over as waves spilled onto the Ennore Expressway, prompting police to divert traffic. The affected stretch was closed and is being monitored by GCC and revenue department officials.
Seawater also entered parts of Thalankuppam but receded before reaching nearby houses, sources said. All coastal habitations had been moved to safety, and officials were maintaining a close watch. Monitoring would continue until the cyclone weakened, Chandramohan said.
The impact was felt in several coastal settlements, including Bharathiyar Nagar, Burma Nagar, Nettukuppam, Thalankuppam, Indira Gandhi Kuppam, Periyakuppam and Chinnakuppam, sources said.
RL Srinivasan, a fisherman from Kattukuppam in Ennore, said, "While the sea would usually turn turbulent twice a month, the waves are not normally this high. With Cyclone Arnab approaching, the impact is evident along the coast. This was not the case years ago. The waves won't reach the roadways most times. But, coastal erosion has brought the sea closer to the road, allowing large waves to spill onto the expressway and disrupt traffic."
Kanchana, a resident of Bharathiyar Nagar, said the waves had disrupted traffic, forcing buses and other vehicles to take diversions. Water had also entered a few shops along the expressway. "If the waves continue to hit the road throughout the night, we are afraid seawater might enter the village," she said.
Police have diverted vehicles along two routes. Those travelling from Ramakrishna Nagar to Annai Sivagami Nagar are being directed via Ernavur Bridge, Murugar Kovil Road and Kathivakkam Beach. Vehicles from Thazhakuppam and Ennore are being diverted via Kathivakkam Bridge and Murugar Kovil Road, officials said.
The situation is being monitored through district emergency operations centres and control rooms, the GCC control room and the SEOC, which is coordinating responses based on field reports.
The government urged people to stay away from the sea and the waterline and not to gather on coastal roads to watch or photograph the waves. Motorists were advised to avoid closed stretches, while residents of vulnerable coastal settlements were asked to follow instructions from the police and district administration.
The Indian Coast Guard has been carrying out sorties for the past two days to ensure fishing boats return to shore amid Sea State 6 conditions, classified as very rough. Such conditions can produce waves four to six metres (13–20 feet) high, posing serious risks to small boats, fishing vessels and some offshore operations. Larger ships could also experience substantial rolling and pitching.