Department of Archaeology to begin underwater survey off Poompuhar- Nagapattinam coast in mid-September

The Tamil Nadu State Department of Archaeology will begin underwater archaeological explorations in the second week of September off the coast between Poompuhar and Nagapattinam, the flourishing port cities of the ancient and medieval periods. The study is aimed at investigating submerged remains and bringing out Tamil Nadu’s maritime past.

Presenting the Tamil Nadu Budget for 2025-26, Minister for Finance Thangam Thennarasu, who also holds the portfolio of Archaeology, had announced archaeological excavations, including deep-sea excavations between Poompuhar, also known as Kaveripoompattinam — the capital of early Cholas — and Nagapattinam, a prominent medieval trade hub with links to Southeast Asia.

According to officials, the proposals have been sent to the Central Advisory Board of Archaeology for clearance. The Department of Archaeology has also sought the support of academic and research institutions in the deep-sea survey. Experts of the Indian Maritime University, the National Institute of Ocean Technology (NIOT), and the National Institute of Oceanography (NIO) will collaborate for the survey.

A research vessel of the NIOT will be deployed, equipped with side scan sonar, a remotely operated vehicle with robotic arms, and high-resolution cameras to document the remains. Given the condition of the sea, it has been decided to conduct the survey in the second week of September, official sources said. 

This is not the first time deep-sea surveys have been attempted off the Poompuhar coast. In the 1980s, the Department of Archaeology and the NIO, led by archaeologist S.R. Rao, carried out geophysical surveys of the seabed. These surveys revealed several structures at depths of 20 to 30 metres.

In 1990, a shipwreck was discovered 4.5 kilometres offshore near  Vanagiri at a depth of 19.5 metres. It appeared to be made of iron, broken into two, and thickly encrusted with marine organisms. A part of the wreck was visible above the seabed, while the rest was buried beneath, said a report published in The Hindu.

Further underwater explorations between 1991 and 1993 revealed man-made structures and brick formations. In 2004, the hydrographic survey ship INS Darshak, deployed by the Eastern Naval Command off the coast of Poompuhar, identified a U-shaped structure at a depth of 23 metres. The ship also recovered the remains of a Dutch vessel believed to have been sunk by the British in the late 18th Century. Among the finds were three lead ingots, each about a metre long and weighing around 80 kilograms.

Recently, the Archaeological Survey of India (ASI) resumed underwater archaeological studies of the submerged remains off the Mamallapuram  coast after nearly two decades.