How to Clean Hong Kong’s Toxic Air

While Hong Kong’s air is significantly cleaner than cities in mainland China, its roadside air pollution is more than five times worse than other major cities like New York

Hong Kong’s roadside air pollution hit record-high levels last month, with new data from the Environmental Protection Department showing that pollution at roadside monitoring stations reached “very high” levels for 9.5 percent of the time in July, August and September. The previous record, set in 2004, was 8.2 percent.

The findings have added to growing alarm about the impact of roadside air pollution. Even as Hong Kong’s overall air quality improves, pollution in the streets is getting worse. But unlike other environmental problems, like climate change, environmentalists say there are a number of straightforward ways of dealing with roadside air pollution, by implementing stricter emission controls and reducing the amount of traffic on the streets.

“When the streets in Central are pedestrianized on Sundays, the air quality is fine, but on normal working days, it keeps getting worse,” says Hung Wing-tat, an associate professor of civil engineering at the Polytechnic University and a director of the Conservancy Association, a green group that has been lobbying the government for more action on air pollution.

At the moment, Hong Kong has some of the worst air quality in the developed world. The World Health Organization considers it hazardous to human health to be exposed over a long period of time to more than 40 micrograms of nitrogen dioxide per cubic meter of air. But the air in busy streets like Hennessy Road in Wan Chai contains up to 480 micrograms per cubic meter, a level so noxious it could lead to serious respiratory illnesses. 1,100 people are killed by the effects of air pollution every year, according to the government.

“It’s a public health epidemic,” says Joanne Ooi, the director of the Clean Air Network. “We need to have air quality objectives that are significantly tighter than the ones that have been in place for 20 years.”

Nearly all roadside pollution is caused by vehicle emissions. “The main pollutants are from commercial diesel vehicles, like trucks and buses,” says Thomas Choi, a senior environmental officer at the green group Friends of the Earth. “But there’s no one measure to get rid of those pollutants — we need to attack them from several different ways.”

The approach favoured by the government has been to tighten emission standards for new vehicles, encourage the conversion of taxis and minibuses from diesel to cleaner-burning Liquified Petroleum Gas (LPG) and to spend HK$3.2 billion on subsidies for bus and truck owners to replace old vehicles with more fuel-efficient ones.

Buses alone account for 40 percent of vehicle emissions, and nearly half the public bus fleet is composed of old, highly-polluting vehicles that confirm only to Euro II emission standards, rather than the Euro V standards that are required for new vehicles. According to an agreement reached between the government and bus companies, Euro II buses will be retired by 2010. But if those old buses are taken out of service immediately, says Choi, up to 200,000 cases respiratory diseases could be prevented.

Stricter emission standards have had a limited impact because commercial vehicles are only inspected for safety and not fuel efficiency, says Hung. “These vehicles are used very intensively. If you’re a taxi driver, your first priority is to run the business, and you won’t allow the vehicle to have a rest.” After several years of such use, even an LPG taxi would exceed emission standards, he says.

What makes the problem even worse is Hong Kong’s densely-built urban environment, which reduces air flow and prevents pollutants from being dispersed. “Even if we emitted the same amount of exhaust as in other cities, the urban canyons create a memory effect, so that the pollutants stay there for up to a month if there is no rain,” says Hung. Even though Nathan Road has a much lower traffic volume than the city’s expressways, it is three times more pollutant, because emissions are trapped by the street’s tall buildings.

While environmentalists say that the most pressing issue right now is to deal with the emissions by old vehicles, a long-term goal would be to focus on what Ooi calls “end-of-tailpipe solutions,” which would prevent Hong Kong’s urban landscape from exacerbating the effects of air pollution. Those include the creation of low-emission zones where traffic is limited, the expansion of Hong Kong’s pedestrian precincts, tree-planting and the creation of more green spaces in congested areas.

In a study on Hong Kong’s most-polluted streets, the Hong Kong University of Science and Technology’s Institute for the Environment proposed that Des Voeux Road in Central be given over to trams and pedestrians, with wider sidewalks and trees along the sidewalks. Similar plans for Queen’s Road Central and some streets in Mongkok were proposed by the government last year, but inter-departmental squabbles have put them on hold. Recently, the part-time pedestrian scheme in Mongkok was scaled back, with Sai Yeung Choi Street re-opened to cars at 11pm each night, an hour earlier than before.

“The Transport Department is not cooperative,” says Hung. “Even if the Environmental Protection Department says that pedestrianization will improve our air quality, the Transport Department says it will worsen congestion. One government department is battling against another. There is no political will to move things forward.”

Others echo that sentiment. “One of the core challenges we’ve been confronting is that there is no one in government who is structurally involved in the process who can raise the alarm and say this is killing a lot of people,” says Ooi. While Secretary for the Environment Edward Yau has been eager to reduce roadside air pollution, he is “one of the least powerful secretaries in the government,” she says.

A spokesman for the government did not respond to questions about roadside air pollution, but Yau recently said that the government is considering a number of ways to improve air quality, including the creation of low-emission zones that only new, fuel-efficient buses could enter. “To make our city low-carbon and green is a vision shared by every one of us,” he said.

But the plan has no timeline for implementation — and critics say that talk is useless without immediate action. “I don’t see any evidence of a forward-thinking vision,” says Paul Zimmerman, the co-founder of Designing Hong Kong, an urban development watchdog. “And if nothing is done, it will only get worse.”

This story was originally published in China Daily on October 15, 2010.

This entry was written by Christopher DeWolf , posted on Monday October 18 2010at 09:10 am , filed under Asia Pacific, Environment, Transportation and tagged , , , . Bookmark the permalink . Post a comment below or leave a trackback: Trackback URL.

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