THE ENVIRONMENT
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These programmes will contribute to much-needed reductions in health-threatening - levels of air pollutants, especially in urban areas, and eliminate many smoky vehicles from the roads. However, if the health-related air quality objectives are to be met, light duty diesel vehicles such as taxis, and public light buses, will have to switch to cleaner fuels such as liquefied petroleum gas (LPG). The government began a trial with LPG taxis in November besides monitoring the development of other clean alternative motor fuels.
The intensive use of roads to cater for the rapid growth in the economy has made road traffic noise one of the most pervasive forms of pollution in Hong Kong. Close to a million people at home suffer road traffic noise higher than 70 dB(A) L10(1 hr), which is the minimum acceptable standard in the Hong Kong Planning Standards and Guidelines.
Pre-emptive planning based on environmental impact assessments remains the most effective way to tackle road traffic noise problems. As a last resort, building insulation may be undertaken to redress the impact on the affected premises. To assess the practicability of installing counter-measures such as roadside barriers and enclosures on existing roads to reduce noise, a Hong Kong-wide consultancy study is under way.
Legislation to control noise from vehicles, a quiet road surface programme and a programme for noise abatement in schools are the major supporting measures that will help alleviate traffic noise problems. By 1997, about 10 kilometres of noisy roads had been resurfaced with a special porous, low-noise road surface bringing some relief to about 14 400 households. Some 9 200 classrooms were treated against noise, benefiting about 430 000 students.
The Kowloon-Canton Railway Corporation has embarked on a 10-year noise reduction programme. It has completed noise mitigation projects at three sites, out of a total of 27. Another project is under way near Fanling centre with a target completion date in early 1998. By then, significant relief will be brought to some 40 000 residents previously affected by rail noise. The Mass Transit Railway Corporation has also completed a noise cover to protect 2 300 residents at Heng Fa Chuen.
Aircraft noise continues to be a major problem for those living under the Kai Tak Airport flight path. Increasing air traffic demand has added to the problem. The government has implemented a comprehensive package of mitigation measures, including an absolute night-time curfew, tight restrictions on late evening arrivals over populated Kowloon, and insistence on the use of quieter aircraft. This noise problem will be satisfactorily resolved when the airport is relocated in April 1998.
Construction and Demolition
Noise from general construction work between 7 pm and 7 am, and on public holidays, is controlled through a Construction Noise Permit system. The permits restrict the use of equipment in accordance with stringent criteria and ban noisy manual activities in built-up areas. Percussive piling work is prohibited during the restricted hours and requires a permit even during daytime. Noisy piling machines may operate up to three hours a day in urban areas but quieter ones can work up to 12 hours. In 1997, some 2 700 permits were issued. There were 370 convictions for work without permits or violating permit conditions. Legislation to phase out the use