The Thailand Underground and Tunnelling Group has suggested the government invest around 200 billion baht to build a 100km-long tunnel under the eastern section of the outer ring road to prevent future flooding in and around the capital.
Suchatvee Suwansawat, TUTG chairman, yesterday said the proposed tunnel should be built from Bang Pa-in in Ayutthaya [north of Bangkok] to Samut Prakan province [the coast].
The project, which could be completed in two years, will help drain water in Lum Luk Ka district of Pathum Thani to the Gulf of Thailand.
The tunnel would be designed as a double-deck underground structure, called a multi-service flood tunnel system, and would also be equipped with hydropower generators for power production, Assoc Prof Suchatvee said.
The upper deck would be used as a road under normal conditions when there were no floods or during minor and moderate flooding.
The lower deck would be used as a flood drain during normal situations or during minor or moderate flooding.
During major floods, the upper deck would be closed to traffic and turned into a floodway to help speed up the drainage of run-off.
Assoc Prof Suchatvee said a similar system should also be considered for the western part of Bangkok.
Large tunnels would be practical, more effective and so the best solution to prevent major flooding over the long run.
Prasong Tarachai, former president of the Engineering Institute of Thailand said the underground flood prevention tunnel system should be built from Nakhon Sawan.
He also suggested integrating 20 state agencies involved in the water management system and creating a more accurate water information system.
“City planning should be revised to include floodways,” he said. “Regulations should be drawn up to specify areas which are reserved as floodways. The floodwater normally flows through these areas for only three months each year, between October and December.
“The people living in the floodways should be properly compensated for allowing water to flow through their land. This should include their expenses in having to modify or lift their homes to avoid possible damage from the water.”
The TUTG will hold the 64-nation World Tunnel Congress 2012 and its 38th General Assembly General Assembly of International Tunnelling and Underground Space Association in Bangkok between May 18 and May 23, at the Queen Sirikit National Convention Center under the theme “Tunnelling and Underground Space for Global Society”.