Electronic Road Pricing (Singapore)

The Electronic Road Pricing (ERP) (Malay: Sistem Elektronik Kadar Jalan ; Chinese: 电子道路收费系统) system is an electronic toll collection scheme adopted in Singapore to manage traffic by way of road pricing, and as a usage-based taxation mechanism to complement the purchase-based Certificate of Entitlement system. The ERP was implemented by the Land Transport Authority in September 1998 to replace the Singapore Area Licensing Scheme after successfully stress-testing the system with vehicles running at high speed. Singapore was the first city in the world to implement an electronic road toll collection system for purposes of congestion pricing. The system uses open road tolling; vehicles do not stop or slow down to pay tolls.

The scheme consists of ERP gantries located at all roads linking into Singapore's Central Area. They are also located along the expressways and arterial roads with heavy traffic to discourage usage during peak hours. The gantry system is actually a system of sensors on 2 gantries, one in front of the other. Cameras are also attached to the gantries to capture the rear license plate numbers of vehicles. Currently, there are 80 ERP gantries in Singapore. New gantries are implemented where congestion is severe, like expressways and other roads.

A device known as an In-vehicle Unit (IU) is affixed on the lower right corner of the front windscreen within sight of the driver, in which a stored-value card, the CashCard, is inserted for payment of the road usage charges. The second generation IU accepts Contactless NETS FlashPay and EZ-Link. The cost of an IU is S$150. It is mandatory for all Singapore-registered vehicles to be fitted with an IU if they wish to use the priced roads.

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