Repair work underway to reduce flooding in Purple Line train tunnel

Workers are increasing efforts to plug the leak in the underground sump of the Purple Line train’s Tao Poon-Rat Burana extension tunnel at Wongwian Yai intersection, while installing a subterranean pumping system to draw water out.

Montri Dechasakulsom, chairman of the Mass Rapid Transit Authority of Thailand (MRT), told the media today that the leak has slowed from 70m3/h last night to about 50m3/h today after the installation of the pumping system, the application of grout to seal the leaks around the sump and the construction of a curtain wall to prevent the leaks.

He claimed that the leaks were caused by defect in the construction process and contractors have been instructed by the MRT to rectify the situation, adding that an artesian well, about 50m deep, will be drilled to reduce the amount of water flowing into the sump.

He confirmed that on-site inspections have not detected any sign of structural collapse, tilting or additional leaks, particularly at the section close to the flyover. To ease public concern over the potential for a building collapse, he said the MRT has asked the Klong San district office to assign engineers to inspect the buildings around Wongwian Yai intersection, to ensure that the buildings are stable.

The construction of the Purple Line extension, between Tao Poon and Rat Burana, is scheduled to be complete by the end of next year.

Meanwhile, traffic flow at Wongwian Yai has been rearranged, with cars arriving from Ban Khaek intersection directed towards the outbound lane of Prachathipok Road, as all the lanes have been blocked to enable temporary road repairs.