Bangkok Water Tunnels

The two tunnels, totalling 31.2km in length, are part of the Seventh Bangkok Water Supply Improvement Project, a series of clean water conveyance tunnels being constructed for the Bangkok Metropolitan Waterworks Authority [MWA].

MWA Contract G-MC-7B, completed in 2003, has a finished internal diameter of 2.30m and is 13.7km long running from New Ngamwongwan Road to a new distribution pumping station in the city’s north eastern satellite town of Minburi. The tunnel will transfer up to 600,000cu m of water per day to a new distribution pumping station.


MWA Contract G-MC-7C, which will convey 800,000cu m per day is presently being constructed, the tunnel is 17.5km long, and will carry water from an existing valve chamber at Thub Chang, in Lad Krabang on the east side of the city, to Bang Plee in Samut Prakarn province. Again the tunnel terminates at a new reservoir and distribution pumping station. After the secondary steel lining is installed, this tunnel will have a finished internal diameter of 2.80m. Tunnel driving was completed in December 2005, and after installation of the secondary steel lining the project will be handed over to the Client in two stages in March and July 2006.