At present, MTR is building more and more rail lines, e.g. Shatin-Central Link, the South Island Line, the West Island Line, etc. to facilitate the movement of people in the population centres not previously covered by the MTR lines. It is obvious that a new railway line will result in imputed economic value of travel time saving, benefits of improved road safety, enhanced development potential of the areas the new line served, financial returns to Government from enhanced property values in the new line catchments, not least environmental health benefits.
Besides, these new lines would take away some passengers from the existing bus and minibus routes and hence would reduce the roadside pollution and improve the overall air quality in Hong Kong.
On the other hand, bus companies and minibus operators may re-route their buses and minibuses to pick up passengers in areas not served by the new lines or to serve passengers between population centres and the new railway stations. Hence, there may be some re-distribution of the vehicular emissions and the roadside pollution.
The net environmental benefits of electrifying the transportation system must be calculated over the areas based on a holistic view of the bus and minibus routings.
Apart from air quality, there may be noise reduction benefits from less vehicles on the road due to the new MTR line and this can make the areas quieter since the MTR cars run mainly underground.
However, there are other factors which might overshadow the environmental benefits, and must be suitably considered before the net environmental benefits can be ascertained.
In the past, the environmental benefits from reduction of pollutants emission were estimated in terms of tons of pollutants/year. In order to include the environmental benefits in the capital budgeting process and hence reflect the actual value of building new railway lines, Dashun Policy Research Centre was appointed by MTRC to carry out a study to evaluate the benefits from improvement of air quality and in particular the costs avoidable from reduction of air pollutants from road transport.