The high-level bridge across Palar river at Thirumukkoodal near Wallajahbad was temporarily closed on Tuesday by the highways department for carrying out repair work.

Traffic on the 790-metre-long two-lane bridge, constructed at a cost of Rs. 7.70 crore and opened five years ago, was diverted to the causeway below.

Recently, vehicle users had noticed strong vibrations while travelling over a part of the bridge. The highways department, during its annual inspection two months ago, found that rubber bearings placed between a span girder and pillar had worn out.

“We decided to replace them. Work has been going on since Tuesday and is expected to get over by Thursday,” said an official source.

The wearing out is attributed to the movement of a large number of over-sized vehicles carrying sand from Thirumukkoodal, and blue metal and earth from Salavakkam.

Every day, around 2,000 Taurus vehicles and 2,500 tractors carrying these materials use the bridge.

Residents of Thirumukkoodal, Pinayur, Pazhaveri and other hamlets located on the southern bank of Palar river also said indiscriminate quarrying of sand in the vicinity of the bridge and persistent movement of heavy vehicles had caused the problem.

“We strived hard for over two decades to get a high-level bridge in place of the river bed causeway connecting Thirumukkoodal on the southern side of Palar river with Chengalpattu-Kancheepuram Road on the other side of the river. However, the bridge has not withstood the weight of the vehicles. It only shows that the highways department has not planned for such heavy movement of vehicles,” said Gunasekaran, a resident of Vayalakavur.

However, a department source said there was no particular period during which the bearings could wear out.

A resident of Pazhaveri said the unchecked quarrying of sand had also affected the environment. “The entire area is dotted with hundreds of quarries. You cannot even stand in the vicinity of a sand quarry for a few minutes. You will go back covered in the grit,” he said.

Department sources said the bridge would be re-opened to traffic in a day or two.