By Nicholas Yong & April Chong

HUNDREDS of cameras will be installed on 10 major road corridors over the next four years in a bid to improve traffic flow.

The Expressway Monitoring and Advisory System (Emas), launched more than a decade ago, is being extended from expressways to major arterial road corridors from next year.

These are stretches of road that link one district to another. For example, Thomson and Upper Thomson roads link the Pan-Island and Seletar expressways.

The 10 chosen corridors are heavily utilised by motorists as alternative routes to the expressways they run parallel to.

Emas was initially installed on expressways to detect and manage traffic by alerting motorists to road conditions. It comprises live video surveillance, incident detection and real-time traffic alert functions.

Its purpose is to help the Land Transport Authority (LTA) respond promptly to and manage congestion arising from traffic incidents, such as vehicle breakdowns and accidents. Emas also despatches recovery vehicles to accident sites to help clear the vehicles off the road.

?By extending the coverage of Emas to the major arterial roads, our traffic control centre will be able to manage incidents on these key road corridors more effectively, bringing about an overall improvement to traffic of the entire road network,? said Dr Chin Kian Keong, the chief transportation engineer at LTA.

On Tuesday, ST Electronics was awarded $40 million to extend Emas to the 10 road corridors in two phases.

Phase one will cover six major corridors, starting with the West Coast Highway corridor and the Woodlands Road- Bukit Timah Road-Dunearn Road corridor. This will be completed by early 2011.

Phase two, which is expected to start in the first half of 2013, will cover the remaining four road corridors.

By 2013, the number of cameras used to monitor traffic conditions will more than double from the existing 309 to 776.

But motorists who use the targeted road corridors are not overly optimistic about the effectiveness of Emas.

Sales manager Herbert Liu, 28, often commutes to work along Upper Serangoon Road. He once took an hour to get to the office because of an accident.

?I think it will help a little but a lot will depend on the reaction time of the people clearing the accident. You can detect the accident faster but do you react faster too?? Mr Liu pointed out.

If there is already a traffic jam along the affected road, it would only serve to slow down recovery vehicles.

Financial executive Rose Lee, 39, is even more pessimistic.

?I don?t think it will help along the Upper Bukit Timah stretch since there are already a lot of cars there during peak hours. At some points along that stretch, there are only two lanes,? said Ms Lee.

nicy@sph.com.sg

Additional reporting by April Chong

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