Abstract
There have been some debates on the effectiveness and efficiency of busway or bus priority implementation since its undertakings in 2004. Questions have been raised regarding its traffic and related environmental impacts, especially to corridor Sudirman-Thamrin. Inherently implementation of busway has occupied one dedicated lane for each direction out of the existing three higher speed lanes and two slower speed lanes. This occupation has, of course, worsened the traffic performance during peak hours, and as can be expected that the impact would cause traffic congestions to some road segments in the periphery at network level as well. Quite recently local government has intention to gain back the existing road capacity at the corridor through the cutting of some road separator between the slower and higher speed lanes, and replace one additional lane upon at the higher speed lanes to alleviate tremendous traffic congestion. To justify such capacity gains study is made to consider merits and demerits regarding the traffic impact and its environmental consequences such as fuel consumption, and CO or NO emissions. Although it is a corridor level implementation, study uses a network level assignment to estimate the changes of traffic flows, and it relates the changes with some emission issues for environmental aspects. Results have shown that some improvements of traffic measures could be achieved with its emission reduction. It is also noticed that little achievement is hard to gain when corridors are at saturated level.
