Falling Concrete in CTE Tunnel Engineers, MP call for thorough check The Straits Times Friday, 11 May 2007     TROUBLED with leaks from the time it opened in 1991, the Central Expressway (CTE) tunnels should be given a thorough check to prevent more slabs of spalling concrete from smashing onto the road. This was what civil engineers, motorists and the deputy chairman of the Government Parliamentary Committee (GPC) for Transport said yesterday, after chunks of concrete came crashing down around 8pm on Wednesday. This happened on the southbound CTE tunnel towards the Ayer Rajah Expressway, near the Havelock exit - a stretch that is built under the Singapore River. Miraculously, the slabs did not hit any vehicle at what is usually a fairly busy time of day in the tunnel. The Land Transport Authority (LTA) says the tunnel was safe and Wednesday"s incident was "an isolated one". LTA chief engineer Paul Fok said checks are done regularly to spot and fix any defects. On top of that, professional engineers inspect all tunnels "at least once every five years" to certify their structural integrity. He added: "The structural integrity of the CTE tunnels is not affected. We have checked the surrounding areas and found no areas of concern." The authorities have insisted that leaks are common in tunnels the world over, although tunnel builders that The Straits Times spoke to say that watertight tunnels are feasible to construct. "There are sections of MRT tunnels here that are dry, even those going under rivers. But others leak," said a construction source. "It all depends on time, cost and the quality of people who designed and built the project."