Cars in Bangkok moved at an average speed of 15 kilometres per hour during the morning rush hour in 2015, a survey by a Transport Ministry agency has found.
The average evening rush-hour speed was 22kph, which was 0.4kph slower than last year while morning traffic moved 0.8kph slower, said the report by the Office of Transport and Traffic Policy and Planning.
The lowest average speed was reported in southern areas of Bangkok covering Phra Chao Taksin, Krung Thon Buri, Mahai Sawan and Charoen Krung roads at 10.1 km/h in the morning. The report said traffic on these roads tended to be congested all day long, especially during the morning and evening rush hours because motorists from the Wong Wian Yai and Ratchaphruek areas on the Thon Buri bank used them to get into the inner city areas.
The five roads in the capital with the worst congestion were:
1. Krung Thon Buri between Krung Thon Buri and Surasak intersection (5.1 km/h)
2. Rama IX between Ramkhamhaeng and Rama IX intersections (9.7 km/h)
3. Charoen Krung between Thanon Tok and Surawong intersections (10.6 km/h)
4. Ratchawithi between Bang Phlat and Uphaichetsadathit intersections (10.8 km/h)
5. Sukhumvit between Asok and Nana intersections (10.8 km/h)
The report concluded that traffic problems in the city had worsened this year because several large mass-transit and other projects were under construction and only 20% of the traffic surface had been returned for use.
As well, it said, the number of newly registered cars has risen sharply since 2012 when the former government introduced hugely popular tax incentives for buyers of first cars.