The Ministry of Transport plans to limit the use of private cars in the notoriously congested central areas of Bangkok to ease traffic, a source close to the Office of Transport and Traffic Policy and Planning (OTP) said.
The source, who asked not to be named, said a team at the OTP is studying solutions adopted in other countries to improve traffic flow in inner city areas.
The team is considering whether to charge drivers who use their private cars in the designated areas or to increase parking fees, the source added.
The ideas are part of the city's traffic flow plans, the source said, adding once electric train projects are completed, some drivers would switch from using private cars to public transit.
Traffic in the city has become very bad, the source noted, citing OTP's figures showing a reduction in the average car speed during rush hours.
The average speed during morning rush hour (6am to 9am) this year is 15 km/h, down from 15.8 km/h last year. The average speed during evening rush hour (4pm to 7pm) this year is 22 km/h, compared with 2.4 km/h last year.
OTP monitored private cars on six main roads in Bangkok by recording the car plate numbers. The study was aimed at comparing traffic flow in each area.
The study showed Krung Thon Buri Road was the most congested road during morning rush hour, followed by Rama IV, Charoen Krung, Ratchawithi and Sukhumvit roads. Charoen Krung Road had the worst traffic during evening rush hour, followed by Ratchawithi, inner Sukhumvit, Pracha Chuen and inner Rama IV.
The biggest cause was an increasing number of private vehicles, the source said, adding that 1,023 new cars and 1,125 motorcycles are being registered daily. The number of private vehicles in Bangkok increased from 8,651,172 in 2014 to 9,018,594 last year, a 4.1% rise.
Another cause of traffic is construction of the Purple, Blue, Red and Green electric train lines.