Brick structure found in Kollidam riverbed traced to Sangam period, was used for water management: T.N. Archaeology Dept.

A view of the brick structure exposed recently on the bed of the Kollidam river at Koogur near Lalgudi in Tiruchi district

| Photo Credit: Special Arrangement

A detailed study by the Tamil Nadu State Department of Archaeology (TNSDA) has concluded that the brick structure exposed recently on the bed of the Kollidam river at Koogur near Lalgudi in Tiruchi district, close to the ancient Kallanai dam, is a Sangam-period water regulation structure.A team of experts from TNSDA, comprising V.P. Yathees Kumar, Joint Director; K. Rajan, Academic Adviser; Prabhakaran, Assistant Director; and Vasanthkumar, Archaeological Officer, conducted the study on August 22 and 23, 2026.Mr. Kumar told The Hindu that the structure became partly exposed after the water level in the Kollidam receded last month. The team used sonar to identify any submerged extensions or other structural remains. Trained divers examined the underwater portions to document the dimensions and construction technique of the brick structure.According to the study, the structure, located about 100 metres from the northern bank of the Kollidam, comprises two sections. The first section runs west to east for about six metres before curving northwards for 8.3 metres. It is about 1.75 metres wide and 1.04 metres high, with 13 courses of bricks visible. Its northern portion remains largely buried under sand.The second section, about 11 metres from the first, is parallel to the first section. It is about 2.15 metres wide, runs east to west for 6.5 metres and then curves northwards for about 4.5 metres. Six courses of bricks are visible in its western portion and three in the eastern portion. The eastern side of the riverbed is slightly higher than the western side, the study said.