Article by SETW on Moving Forward to Clean Seas and Clear Waters

Dr Sarah Liao, Secretary for the Environment, Transport and Works

In the next ten years, to enhance our water quality and protect public health the Government plans to invest almost as much money (about $20b) in new sewerage and sewage treatment facilities as it has in the last twenty.  As well as the capital cost, which will be borne by the Government, there will be additional operating expenditure of about $1.3b per annum. We are glad that the adoption of the polluter-pays principle has taken root in the community.  The firm support expressed by LegCo Members has also laid the cornerstone of the package of measures needed to take our sewage services to the next level.

Legislation for the proposed increases in the sewage charge is now before the Legislative Council.  The average domestic sewage charge at the moment stands at $11 per account per month.  To fund the operating costs of our planned sewage services that will have to rise to $27 per month in 10 years' time. This translates to a modest increase each year over a period of ten years of no more than 10 cents per day.  The arrangement will provide a predictable, sustainable and stable funding support to the operation of these important facilities. Subject to the smooth and speedy passage of the legislation, the Government will seek funds for the construction of the centrepiece of the future programme, namely the Harbour Area Treatment Scheme (HATS) Stage 2A which will finally rectify the highly unsatisfactory situation that sees hundreds of thousands of tonnes of wastewater still being discharged largely untreated into Victoria Harbour daily.  HATS 2A will involve collecting up the untreated sewage from the north and west shores of Hong Kong Island and transferring it through deep tunnels to Stonecutters Island for chemical treatment before disinfection and discharge in the western anchorage area.  It will cost $8b to build and about $420m per annum to operate, but when commissioned in 2014 it will improve water quality, and reduce the bacterial levels in the main harbour area by a further 90%  so that we will finally be able to resurrect the annual cross-harbour swim and hold other water-based recreational activities.

To bring about early improvements in the western harbour we plan to advance the disinfection facilities so that they can be completed in about two years' time and allow early re-opening of some of the closed beaches in the Tsuen Wan district.  To achieve this early benefit a technical option is to chlorinate the effluent to kill the germs, then dechlorinate it to remove any residual chlorine. The environmental impact of this is being assessed in a study, the findings of which would be subject to public inspection and comment under the Environmental Impact Assessment Ordinance. Some environmental professionals have raised concerns about the potential environmental impact of chlorination. However it is relevant to note that chlorination is a widely used disinfection technique for treated sewage effluent. Its use continues to be adopted in many places overseas, with the appropriate dechlorination step added to remove the residual chlorine.  On the other hand, because of land zoning and the possible need for a new power sub-station, the adoption of UV for disinfection will take substantially longer to deliver and could only be brought on stream at the same time as the main Stage 2A works are commissioned in 2014.  A lot of people in the community would prefer not to have to wait that long to be able to access recreational facilities near Tsuen Wan again. And rightly so.