Grouse: The intent of ERP is to stop people from driving.

MOT: If that is the intent, it would be easier for the Government to just ban cars. But this would be counterproductive, after having invested heavily in the road network.

The intent of ERP is to persuade enough motorists against driving at a particular time, so those who choose to pay to do so can have a smoother travel.

Grouse: Evening ERP is not pro-family as people end up getting home later.  

If traffic is allowed to build up in the evening peak hour, it will be a matter of time before the roads become congested.

When that happens, all commuters - including those taking buses - will get stuck in traffic. Not only will everyone get home late, they will also not be able to predict their travelling time.

Grouse: ERP is a revenue-generating measure.

MOT: The Government is actually giving back to the motoring public more than what it earns in ERP revenue.

Since 1998, each time it has adjusted the ERP system to manage congestion through vehicle usage charges, vehicle ownership costs have tumbled.

The Government is forgoing $1.2 billion in revenue a year from vehicle ownership taxes such as the Additional Registration Fee (ARF), excise duty and road taxes, but making back $100 million a year through ERP -a net loss in revenue.

With this year's lot of new ERP gantries going live, the Government again cut road taxes and ARF by $310 million a year. But revenue from the new gantries and revised charges will bring it only $70 million.

Grouse: Saturday ERP is unnecessary.

MOT: Congestion imposes a cost on the economy and society, regardless of when it occurs. The costs include time wasted, uncertainty over travel time and fuel burnt.

Grouse: ERP is ineffective in curbing traffic congestion.

MOT: ERP has been effective in keeping traffic speeds above 45kmh on expressways and above 20kmh on arterial roads.

Before ERP came to the ECP in 1998, vehicles there were crawling at 36kmh between 8.30am and 9am. Today, the average speed is above 50kmh during that half hour.

Grouse: The Government relies only or mainly on ERP to deal with congestion.

MOT: There is no single solution to managing congestion. The Government is also building new roads, widening existing ones and employing technology to increase the capacity of the roads. It is also working with public transport operators to improve the quality and capacity of public transport.

Grouse: Building more roads will solve the congestion problem.

MOT: It may do so at the start, but over time, good driving conditions will encourage more to drive and congestion will be back.

The Government can build only so many more roads. As it is, they already take up 12 per cent of the land here. Viaducts are unsightly, and underground roads, expensive.

Grouse: Cutting down the car population will solve the congestion problem.

MOT: The Government is reducing the rate of growth of the vehicle population in line with the slowdown in road building, but road congestion is a function of both vehicle population and how frequently vehicles are used.

Reducing the number of cars is a blunt tool for addressing congestion, since it will also affect people who use uncongested roads - hence the need for a tool like ERP, which can target congestion when and where it occurs.

Grouse: ERP is unfair as some people have no choice.

MOT: ERP is imposed based on the amount of congested road space a vehicle uses. This principle of pay-as-you-use is fair, since all who drive on ERP-priced roads benefit from smoother traffic.

This article was first published in The Straits Times on Sep 6, 2008.

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