The route will be developed as a monorail and will include 22 stations, running from Kae Rai via Ngam Wong Wan Road and Kaset-Navamin Road to Lam Salee. It will offer interchanges with the planned 35.5km Pink Line at Kae Rai, which will also be a monorail with a tender set to be announced by the end of September, the under-construction 23.5km Purple Line, which is due to open in 2015, on Rattanathibet Road, the planned Red Line commuter service at Bang Khen prison, and the Green Line at Kasetsart University.
MRTA confirmed that it plans to use pillars built by Expressway Authority of Thailand in the middle of Kaset-Navamin Road for the project after an elevated highway extension project was abandoned in favour of the monorail.
The Brown Line plan will be submitted to the Transport Ministry in September for final approval, and if secured, design work is expected to be completed in 2016 with a tender for the construction contract expected to be announced in 2017. The line will take three years to build and is scheduled to open in 2021.
Meanwhile, C H Karchang Public Company, which secured the Baht 13.17bn ($US 423m) civil works contract for the 12.6km extension of Bangkok Metro's Green Line in March 2012, and the Baht 2.24bn trackwork contract earlier this year, has awarded Alstom a €14m contract to design and construct trackwork and a third-rail electrification system for the project.
The extension will add nine stations to the line from its existing terminus at Bearing to Samutpakran and will carry up to an additional 57,000 passengers per day. Alstom will also design and construct a new depot for 40 three-car trains which will serve the extended line.
Construction of the Green Line extension is due to commence by the end of 2014 and be completed in 2017.