Ships and port operations add to air pollution

PUBLISHED : Sunday, 14 October, 2007, 12:00am
UPDATED : Sunday, 14 October, 2007, 12:00am

New figures show harmful sulfur dioxide emissions are increasing

The emission of sulfur dioxide, a harmful air pollutant, by the shipping industry is on the increase, according to the latest government figures.

The Environmental Protection Department released data last week showing that the emission of sulfur dioxide from vessels has increased by 16 per cent between 2001 and 2005, the most recent year for which the government had given figures.

The announcement follows Chief Executive Donald Tsang Yam-kuen's policy address on Wednesday that the government will strongly encourage ferry operators to switch to cleaner fuel.

But critics argue that ferry emissions are only a small part of the problem and that the government should look at all vessels as well as port operations. They say these boats could also be polluting the air and posing a particular health threat to people living and working near the harbour.

A joint study in 2005 by the Hong Kong University of Science and Technology (HKUST), the University of Southern California and the think-tank Civic Exchange showed that residual oil combustion for marine vessels around the Kwai Chung Terminal container port was responsible for about 36 per cent of the sulfur dioxide measured at the department's general air quality stations.

Local power plant emissions, by contrast, were responsible for only 7 per cent of sulfur dioxide levels.

Alexis Lau Kai-hon, an atmospheric scientist at HKUST, said that after the ships emitted the fumes, sea winds blew them into areas in the vicinity.

'Kwun Chung, Tsuen Wan and all the coastal areas face the same problem,' Professor Lau said.

The International Council on Clean Transportation released a study in March, saying that ocean-going vessels were rapidly overtaking vehicles as the No1 air polluter by producing more sulfur dioxide than all the world's cars, trucks and buses combined.

But in Hong Kong, Civic Exchange chief executive Christine Loh Kung-wai argues that the government has not focused on marine emissions and emissions from port operations because the total tonnage from these sources is a lot less than from power plants and vehicles.

'We think this is the wrong way of looking at the problem,' she said. 'While total tonnage is a factor, where the pollution is generated and dispersed is also important. Pollution from ships and logistics [companies] gets right to where people live and work, and the very high toxicity of shipping fuel presents a very large health threat. This is a point the Hong Kong government does not address.'

Wong Shiu-on, a resident of South Horizons, says he sees black smoke emitting from cargo vessels every day. He notes that not only do vessels sailing to Hong Kong enter the port, but so do vessels sailing to other ports in the southern part of China.

These in-transit vessels sail through the East Lamma Channel, bypassing the Ma Wan Channel in approaching the Shenzhen ports.

'The bulk vessels, especially those sailing to Shekou, are usually very old and produce much darker smoke while navigating. But it's hard for the marine department to catch them because most of these vessels only pass by Hong Kong waters,' Mr Wong said.

Currently, the Shipping and Port Control Ordinance stipulates that no vessel in Hong Kong waters shall emit smoke in large enough quantity to be a nuisance, yet only a few vessels have been caught in the past three years.

The Marine Department conducted 58 inspections in 2006 on smoke emissions from sea vessels. These inspections yielded 11 prosecutions and seven convictions, with the worst fine HK$6,000.

A spokeswoman for the Marine Department admitted that catching polluters at sea was difficult because the smoke they produced dispersed after about 10 seconds, so it was difficult to classify such smoke as 'a nuisance'.