LCQ16: Coastal waters quality of Victoria Harbour

     Following is a question by the Hon Chan Hak-kan and a written reply by the Secretary for the Environment, Mr Wong Kam-sing, in the Legislative Council today (February 24):


     The Government has advised that it has all along been taking actions and allocating resources to improve and enhance the quality of the coastal waters of Victoria Harbour.  However, the coastal waters of Victoria Harbour still give off stenches from time to time, which has caused great nuisance to members of the public.  On June 26 last year, the Finance Committee of this Council approved a funding application for commissioning a consultancy study on how to reduce near shore pollution and enhance the quality of the coastal waters of Victoria Harbour, but the two-year consultancy study will only commence early this year.  In this connection, will the Government inform this Council:

(1) given that between 2013 and September 2015, the Environmental Protection Department uncovered a total of 157 cases in which the foul water pipes of private buildings were misconnected to the stormwater drainage system within the Victoria Harbour Water Control Zone, but the authorities instituted only 16 relevant prosecutions between 2012 and 2014, of the reasons why the authorities did not prosecute the relevant parties of the remaining cases; whether they will consider stepping up their law enforcement efforts; if they will, of the details;

(2) given that problems such as inappropriate handling of minor works or drainage works by minority property owners and contractors, the lack of expertise of the workers making pipe connections, and the complicated pipe alignments of old buildings may result in foul water pipe misconnections, whether the authorities will step up the regulation of implementation procedures for those works, so as to prevent the misconnection of foul water pipes; if they will, of the details; if not, the reasons for that;

(3) given that roadside activities and phenomena (e.g. discharge of sewage generated by eateries' dishwashing activities at rear lanes into stormwater drains, and the flow of street litter into stormwater drains) are some of the sources of coastal shore water pollution, whether the authorities have formulated measures to reduce the pollution caused by such activities to the quality of coastal shore waters; if they have, of the details; if not, the reasons for that;

(4) of the respective rates of compliance with the Water Quality Objectives (i.e. dissolved oxygen, total inorganic nitrogen, unionized ammonia nitrogen and E coli bacteria) of the various Water Control Zones in Hong Kong in the past three years; and

(5) whether the authorities have set performance indicators for the plans on improving the harbour water quality, so as to assess the effectiveness of the works of Stage 1 and Stage 2 of the Harbour Area Treatment Scheme, which costed more than $8.4 billion and $17.3 billion respectively; if they have, of the details; if not, the reasons for that?



     The Government is committed to improving the water quality of Victoria Harbour.  Over the past two decades, we have progressively implemented the Harbour Area Treatment Scheme (HATS) to collect and treat sewage generated around Victoria Harbour. With full commissioning of HATS Stage 2A in December 2015, all sewage around the harbour has been intercepted and diverted to the Stonecutters Island Sewage Treatment Works for centralised treatment. Compared with the monitoring data in the first quarter of 2015, the levels of E coli and organic pollutants in terms of biochemical oxygen demand have significantly reduced by 74 per cent and 20 per cent respectively. The reductions for the above parameters were 88 per cent and 50 per cent respectively as compared with the year 2000-2001 before HATS Stage 1 was implemented.

     However, there are still residual pollution discharges to some coastal waters of Victoria Harbour, even causing odour problems. The Environmental Protection Department (EPD), in collaboration with other relevant departments, have been taking various actions including law enforcement, publicity and education and engineering measures, to reduce the residual pollution discharges entering Victoria Harbour. However, many of the residual pollution discharges originate from various activities in old districts and the causes would differ among different areas.  While efforts among the departments can mitigate the problem caused by residual pollution discharges, it is not adequate to keep the problem totally under control. Hence, the Government has commissioned a consultancy study (the Study) in January 2016 to identify the specific causes of near shore pollution through evidence-based reviews and various analyses, based on which targeted solutions and measures through pollution control and prevention at source would be identified.

     In parallel to the Study, we would take immediate measures to deal with any pollution problem identified, instead of waiting for completion of the Study.  On the other hand, we are actively preparing for the construction of dry weather flow interceptors (DWFI) and rehabilitation of trunk sewers in Kowloon and Tsuen Wan, including a DWFI at the Cherry Street Box Culvert to intercept polluted flow from entering the New Yau Ma Tei Typhoon Shelter; four new DWFIs in Tsuen Wan and four new DWFIs in West Kowloon at critical locations; the upgrading of 43 existing DWFIs in West Kowloon; and the rehabilitation of two trunk sewers in To Kwa Wan and Kwun Tong.  These engineering measures could help reduce residual pollution discharges entering Victoria Harbour and improve the quality of the coastal waters of Victoria Harbour.

     Regarding the questions raised by Hon Chan Hak-kan:

(1) There are many causes for sewer misconnections in buildings. For example, renovation or alteration works of buildings and repair of broken sewer pipes may result in the misconnection of sewer pipes to the storm drain systems. Misconnections may also involve sewer pipes of individual units as well as sewerage installation on external walls and common areas of buildings; these contraventions are usually not intended by the owners or occupants. Hence, we would focus on facilitating owners or occupants in resolving the sewage disposal problems of their buildings. If there is sufficient evidence of illegal discharge, we will also initiate prosecution actions. During 2013 to 2015, the EPD had identified 177 misconnection cases in the Victoria Harbour Water Control Zone (VHWCZ). Through EPD's efforts in liaising and following up with the owners' corporations, individual owners or occupants, and property management offices, 137 cases have been rectified.  As for the remaining cases, the EPD are following up with the Buildings Department (BD) and other relevant government departments to urge the concerned property owners and responsible parties to actively and quickly rectify the problems.

     Furthermore, the EPD will inspect potential sources of illegal discharge in the VHWCZ, including construction sites, various industrial and commercial premises, restaurants and food premises, etc.  In the past three years (2013 to 2015), the EPD conducted over 7 000 inspections and successfully prosecuted 22 cases for violation of the Water Pollution Control Ordinance.  The EPD will continue its enforcement efforts to improve the quality of the coastal waters of Victoria Harbour.

(2) Under the current Minor Works Control System (MWCS) of the BD, designated minor works involving the erection, repair, alteration or removal of any drain shall be carried out by a qualified and experienced Prescribed Building Professional and Prescribed Registered Contractor in accordance with the Buildings Ordinance and Building (Minor Works) Regulation. The BD has issued the "Technical Guidelines on MWCS", which provides detailed references for different types of minor works items including drainage works to assist the professionals and contractors in carrying out the works.  The BD will carry out audit checks on a random basis to ensure the minor works comply with the requirements of the legislation and achieve the required quality and standard. Non-compliance cases are subject to disciplinary action and prosecution.

(3) At present, should illegal discharge of wastewater into the storm drains be found, the EPD will conduct follow-up investigation and take enforcement actions against any violation of the Water Pollution Control Ordinance, and initiate inter-departmental enforcement actions if necessary. The Food and Environmental Hygiene Department (FEHD) would also arrange inspections at restaurants and take enforcement actions to stop the malpractice of scullery activities at rear lanes. Over the past three years (2013 to 2015), apart from the prosecutions taken by the EPD (see part (1) above), the FEHD has also taken enforcement actions and successfully prosecuted 97 cases against illegal discharge of wastewater from restaurants.

(4) The compliance rates with the four Water Quality Objectives (WQOs) parameters for marine waters (i.e. dissolved oxygen (DO), total inorganic nitrogen (TIN), unionised ammonia nitrogen (UIA) and E coli) in the 10 Water Control Zones during the past three years (2012 to 2014) are listed in the Annex. In 2014, the overall DO level was lower than that in 2012 and 2013. According to the Hong Kong Observatory (HKO), the weather was extraordinarily hot from June to September in 2014, with June, July and September the hottest months in HKO's record since 1884. As high temperatures can significantly reduce the solubility of oxygen in water, EPD's assessment indicates that the lower DO level in 2014 was likely related to the hot weather that year, and was not due to increased pollution. The EPD will continue to closely monitor the changes in DO levels in the marine waters.

(5) The Government established the WQO for Victoria Harbour in 1994 based on its primary beneficial use of navigation and anchorage. The key parameters include DO, UIA and TIN. The commissioning of HATS Stage 1 in 2001 has brought significant improvement in water quality of Victoria Harbour, leading to an increase of 10 per cent in DO, and a decrease of 31 per cent and 16 per cent in UIA and TIN respectively. The progressive commissioning of HATS Stage 2A since September 2015 leads to further improvement in the water quality of Victoria Harbour. We expect that there will be a further increase of 3 per cent in DO, and a further decrease of 12 per cent and 7 per cent in UIA and TIN respectively.  Although E coli is not a WQO parameter for Victoria Harbour, the levels of E coli and organic pollutants in terms of biochemical oxygen demand, as mentioned in the beginning, have significantly reduced by 74 per cent and 20 per cent respectively as compared with the monitoring data in the first quarter of 2015. When compared with the pre-HATS Stage 1 data in 2000 to 2001, the reductions for the above parameters are 88 per cent and 50 per cent respectively. HATS has also helped improve the water quality of beaches outside Victoria Harbour. Since 2010, the water quality of all beaches in the territory has met the bacteriological WQO for bathing beaches. The Government will continue to closely monitor the relevant parameters to confirm the effectiveness of the various improvement measures.

Ends/Wednesday, February 24, 2016
Issued at HKT 15:38