We refer to the letters from David Lai ("A roundabout solution to traffic woes", October 23), Kevin Lee ("City's drivers puzzled by roundabouts", October 29) and Howard Cowley ("Roundabouts perfect for intersections", November 1).
Currently, roundabouts, signal-controlled junctions and priority (stop/give way) junctions are used on our roads. The choice to adopt types of junctions is based on traffic consideration and land availability. The Transport Department does not have a general objective to replace roundabouts with signal-controlled or priority junctions.
In general, priority junctions are suitable for low to moderate traffic flow.
For higher volume of flow, roundabouts or signal-controlled junctions are considered but they have their pros and cons. While roundabouts cause less delay, long traffic queues may build up if flows from different directions are not balanced. Also, roundabouts occupy more land and cannot have signalised pedestrian crossings. Signal-controlled junctions take up less land and are better able to cater for unbalanced traffic flows and pedestrian crossings. However, delays cannot be avoided, especially during off-peak hours.
As traffic conditions may change over the years, it may be necessary to convert a junction. We consider each case on its merits and choose the most suitable junction type according to the prevailing traffic and site conditions.
It is true that compared with some overseas countries, there are fewer roundabouts in Hong Kong.