Scheduled to be delivered over the next 30 months, the order is intended to meet the expected boost in ridership following the opening of the On Nut - Baring extension of the Sukhumvit Line in August 2011. Once open, the extension is anticipated to increase average daily ridership to 500,000 from 460,000 at present.
Beginning next month, BTS is also introducing 12 new four-car trains that have been ordered from CNR to its fleet which will be used on the congested Silom Line, with the three-car trains currently used on the line transferring to the Sukhumvit line. Capable of transporting 1490 passengers compared with 1106 on the Siemens fleet, the CNR trains will increase capacity by 30%.