A government review of public parking rates is currently under way in a move that is set to raise prices at all public carparks, The Straits Times has learnt.

The Housing Development Board (HDB) and Urban Redevelopment Authority (URA) both confirmed yesterday that an islandwide review of both short-term and season parking schemes is in the works.

This comes just two months after the ministries of National Development and Transport said in Parliament that parking prices would go up, to bring Singapore's rates in line with those of other global cities.

The URA said the review is meant to "right-price public car park charges and reduce the gap between the fees charged by private and public carparks". It is studying the quantum of increase.

It noted that in some areas in the Central Business District, the difference between private and public hourly parking prices during peak periods was over 100 per cent.

Separately, the HDB pointed out that its carparks have improved over the years, with amenities such as landscaped decks, electronic parking systems and lifts.

Both agencies noted that the last price revision was in 2002, when short-term parking prices increased about 10 per cent - carparking charges in the city area rose from 90 cents to $1 per half-hour, and from 45 cents to 50 cents per half-hour outside the CBD.

"Since then, the costs of managing and operating carparks have increased substantially," said a URA spokesman.

Before 2002, prices were also hiked in 1993 and 1989 - in all cases, the increase was over 10 per cent. The HDB and URA manage 607,000 and 24,000 parking spaces respectively.

The HDB is also studying differentiated season parking charges for non-residents who use HDB carparks, and residents who own more than one car. It said differentiated rates could help manage demand, with priority given to a resident's first car.

Motorists hope prices would not increase beyond 10 per cent. "Already, we spend a substantial amount on our cars," said technopreneur Toh Kian Khai, 34.

A parking policy expert, Dr Paul Barter, said a review was timely, but recommended taking a more nuanced approach. Prices should be set based on the occupancy rate of carparks - which ideally should only be 85 per cent full at any one time so that there are always parking spaces available. Rates could be raised during peak periods and lowered in the off-peak, he said.

"If it's too full, it's too cheap, and if it's too empty, it's too expensive," he said.