LCQ5: Quality of coastal waters of Victoria Harbour

     Following is a question by Dr the Hon Priscilla Leung and a written reply by the Secretary for the Environment, Mr Wong Kam-sing, in the Legislative Council today (January 20):

Question:

     Some members of the public complained to me that the coastal waters (particularly in the vicinity of the Hung Hom Promenade) of Victoria Harbour (the Harbour) give off unbearable stenches from time to time, causing nuisance to members of the public. It is learnt that one of the sources of the stenches is the discharge of sewage from certain private buildings in the Kowloon West District into the Harbour as their foul water pipes have been wrongly connected to the stormwater drainage systems (misconnections of foul water pipes). On the other hand, the Environmental Protection Department commenced a consultancy study in 2016 to further enhance the quality of coastal waters of the Harbour. In May 2019, the Government indicated that the consultant would submit a report of the entire study within that year. In this connection, will the Government inform this Council:

(1) of the annual Water Quality Objectives compliance rate of the Victoria Harbour Water Control Zone in each of the past two years;

(2) of the number of cases of misconnections of foul water pipes which the Government followed up in each of the past three years and, among such cases, the number of those which have been rectified, with a breakdown by District Council district;

(3) among the cases mentioned in (2), of the respective numbers of those in which (i) rectifications were made after the owners had been given warnings/advice, (ii) rectifications were made after the owners had received statutory repair/removal orders or had been prosecuted, (iii) rectifications were still not yet made after the Government had taken law enforcement actions, and (iv) rectification works were carried out by government contractors; whether it has reviewed the effectiveness of the relevant law enforcement actions; if so, of the outcome; and

(4) when it will publish the report of the aforesaid consultancy study; what measures the Government will take to follow up the recommendations put forward in that report for improving the quality of coastal waters of the Harbour and addressing the problem of near-shore stenches, as well as the implementation timetable and estimated expenditure for such measures?

Reply:

President,

     The Government has all along been attaching great importance to improving the water quality of Victoria Harbour and has devoted significant resources to improve the sewage collection and treatment systems through implementing the Harbour Area Treatment Scheme and works for enhancing the quality of coastal waters of Victoria Harbour, stepping up enforcement on misconnections of sewage pipes, and clearing sediment from the stormwater drainage systems. These efforts have brought noticeable improvement in the water quality of Victoria Harbour.

     My reply to the question raised by Dr the Hon Priscilla Leung is as follows:

(1) The overall Water Quality Objectives (WQOs) compliance rate for the Victoria Harbour Water Control Zone (WCZ) in the past two years are tabulated below:
 

Year Overall marine WQOs compliance rate for
the Victoria Harbour WCZ
2018 97 per cent
2019 97 per cent

Note: The overall WQOs compliance rate for 2020 is pending computation as the water samples collected in December 2020 are still under testing.

(2) The statistics of Government’s follow-up actions on foul sewer misconnection in various districts in the past three years are tabulated below:

Cases of foul sewer misconnection found in Victoria Harbour WCZ

District Number of foul sewer misconnection cases
(Number of cases rectified)
2018 2019 2020
Central and Western 7 (3 cases) 6 (2 cases) 3 (0 case)
Eastern 15 (6 cases) 11 (6 cases) 4 (3 cases)
Wan Chai 15 (13 cases) 7 (2 cases) 1 (All)
Kowloon City 15 (7 cases) 8 (0 case) 5 (1 case)
Kwun Tong 10 (8 cases) 0 1 (All)
Sham Shui Po 7 (4 cases) 1 (0 case) 4 (1 case)
Wong Tai Sin 7 (3 cases) 4 (3 cases) 2 (1 case)
Yau Tsim Mong 45 (31 cases) 63 (23 cases) 38 (8 cases)
Kwai Tsing 2 (All) 0 2 (1 case)
Tsuen Wan 7 (4 cases) 7 (5 cases) 3 (0 case)
Total 130
(81 cases)
107
(41 cases)
63
(17 cases)

(3) Among the 300 cases mentioned in (2) above, 118 cases were rectified by owners after issuance of warnings or advice, 21 cases were rectified by owners after the statutory repair or removal orders were served, while 57 cases have not been rectified after statutory repair or removal orders were served. There were no rectification works carried out by government contractors in the same period. We will continue to follow up on the remaining cases, urge or order the respective owners to fulfil their responsibility to rectify the pipe misconnection problems. For cases of non-compliance with the orders, the Buildings Department will take appropriate enforcement actions according to the circumstances, including consideration to initiate prosecution under the Buildings Ordinance.

(4) The consultancy study on further enhancement of the near-shore water quality and the general environment of Victoria Harbour has been completed. The consultants are now working on the final collation and editing of the study report and the Government will publish the study report summary in the second quarter this year.

     The findings of field surveys on pollution sources show that the near-shore pollution problems of Victoria Harbour are mainly caused by pollutants discharged from stormwater outfalls. This is probably due to misconnection of sewage pipes to stormwater drains and non-point source pollution (e.g. leakage from ageing sewers, street activities and cleansing of public places, etc.).

     The Government is gradually implementing a series of measures based on the study results and recommendations, including expediting the rectification of sewer misconnections; carrying out inspection, maintenance and desilting for public sewers and stormwater drainage systems on a regular basis; and expanding the application of “odour-control hydrogel” to mitigate the odour problem of stormwater outfalls, etc.

     At the same time, the Government is also progressively implementing targeted pollution control works projects, including construction and modification of dry weather flow interceptors (DWFIs) and rehabilitation of ageing sewers. The Government is now executing works under two projects of a total value of $1,000 million on the construction and modification of 52 DWFIs at various locations of West Kowloon and Tsuen Wan. Four of the DWFIs in Tsuen Wan had been completed in advance in October 2019, and the works are expected to be wholly completed in 2022. Another project with $100 million approved by the Legislative Council in 2020 for the construction of DWFIs at eight locations in Tsuen Wan and Kwai Chung had started in the same year and is expected to be completed in 2023. Furthermore, the programme on installation of compact and high-efficiency DWFIs along Victoria Harbour has also commenced, with projects covering locations of Hung Hom, Wan Chai East, Causeway Bay Typhoon Shelter, Shau Kei Wan Typhoon Shelter and Tsuen Wan Bay included in the Public Works Programme in 2019 and 2020 and associated engineering studies progressively commenced. These projects, each of an initial cost estimate of about several hundred million dollars, are anticipated to be completed in the period from 2026 to 2028. On the other hand, sewage leakage from ageing sewers may also be a source of pollution to the coastal waters. Regarding the rehabilitation of ageing sewers, five works projects with total funding of $3,600 million approved by the Legislative Council are in progress. Twenty-six kilometres of sewers will be rehabilitated and 75 kilometres will be investigated across the territory within five years under these projects. The Government will continue to formulate works projects for rehabilitation of other ageing sewers.

     The Government will continue to take enforcement actions, implement works projects for reducing the discharge of pollutants along Victoria Harbour and raise public awareness on reducing discharge of pollutants to stormwater drains at source, in order to improve the near-shore environmental and odour problems.