Environmental Protection Department Environment Hong Kong 2004
Vision and Mission Foreword Contents Home English Traditional Chinese Simplified Chinese
1. Hong Kong's Environment 2. Community Awareness 3. Customer Service and Partnership 4. Environmental Assessment and Planning 5. Air 6. Noise 7. Waste 8. Water 9. Enforcement

Resource Materials


To achieve marine and fresh water quality objectives that will safeguard the health and welfare of the community and meet various conservation goals, by planning for the provision of sewage facilities, intervening in the planning process and enforcing the controls in the Water Pollution Control Ordinance and the Dumping At Sea Ordinance.
Chapter 8


Highlights in 2003
Completed the Mirs Bay Water Quality Regional Control Strategy with the Shenzhen Environmental Protection Bureau.
Substantially completed three major studies on the Harbour Area Treatment Scheme, in preparation for public consultation.
Completed the reviews of sewerage master plans to meet demands from development needs up to 2016.
Developed a proposal for effluent reuse demonstration in North District.






The shape of Victoria Harbour and the quality of its water have been the subject of much debate in recent years. While many of the issues are yet to be resolved, the fact that people are speaking out so passionately about the harbour is a positive and welcome sign. The harbour has come to represent something that is alive and valued in Hong Kong, a place that people want to get close to, to see and smell, and to protect. Instead of being viewed as a dumping ground, as in the past, our waters have come to be treasured.

The Environmental Protection Department (EPD) plays an important role in fulfilling the public's aspirations for a cleaner water environment. Many positive improvements have been made in the central and eastern parts of the harbour, as well as in beaches, rivers and streams further afield. However, these improvements were neither cheap nor simple to achieve and much more work and investment is still needed to improve water quality in all areas of Hong Kong. As the community takes the harbour less for granted, it must appreciate that achieving cleaner water is an expensive and complicated business.

Hong Kong's Victoria Harbour.
Hong Kong's Victoria Harbour.


Stonecutters Island Sewage Treatment Plant plays a key role in the Harbour Area Treatment Scheme.
Stonecutters Island Sewage Treatment Plant plays a key role in the Harbour Area Treatment Scheme.

When people talk about water quality in Hong Kong, they invariably focus on Victoria Harbour. It is not only the largest water body in the SAR, but also absorbs the largest amounts of pollution. About four million people live alongside the harbour and, until 2001, 1.7 million tonnes of their untreated sewage was dumped into the harbour each day for disposal. This led to unacceptable levels of water pollution. At the end of 2001, a major turnaround in water quality was achieved with the commissioning of the first phase of the Harbour Area Treatment Scheme (HATS).

HATS involves collecting and treating all of the sewage around the harbour before disposal. The first phase covers Kowloon and eastern Hong Kong Island, which produce 70 per cent of the sewage output. This sewage now receives chemically-enhanced primary treatment before being disposed of in the western harbour. As a result, bacteria and ammonia levels have dropped significantly in the central and eastern parts of the harbour while dissolved oxygen has increased in all areas of the harbour.

This good news is tempered by the fact that the multi-billion dollar HATS project still requires considerably more investment before water quality can improve in the rest of the harbour. Moreover, there is not yet a community consensus on the best level of treatment. A panel of international experts was appointed in 2000 to provide guidance on the matter and recommended a higher level of treatment so all treated effluent could be discharged into Victoria Harbour without affecting water quality. Since then, the EPD has been studying various aspects of their recommendations to provide more information for public debate.

Biological aerated filter technology is recommended for providing higher level of treatment for wastewater.

Biological aerated filter technology is recommended for providing higher level of treatment for wastewater.

Three major studies into the panel's recommendations were mostly completed at the end of 2003. They concluded that biological aerated filter (BAF) technology - which was recommended by the panel - is feasible for Hong Kong and could treat the water to a very high level. However, the recurrent expenditure of BAF would be several times that of chemically-enhanced primary treatment. Identifying suitable sites for BAF technology is also not a simple matter. Four sites were suggested in the panel's report. One, the old quarry on Lamma Island, has sufficient land. But the site of the current treatment plant on Stonecutters Island is too small and more land would need to be acquired if a BAF plant were built there. Two other options, at North Point and Sandy Bay, would require placing the facility underground. The consultants also suggested that a single private operator should design, build and operate the treatment facility.

The study results will be circulated in 2004 for public consultation on the best way forward. Clearly, a higher level of treatment will be more expensive, but it will also provide a cleaner harbour. The debate over the sewage strategy has been an emotional one, reflecting the public's depth of feeling for the harbour. But the next stage will require cool thinking and decision-making on what is best for the harbour and for Hong Kong.


Hong Kong's sewerage network has come under strain on several fronts in recent years. A growing population, new developments and enhanced environmental standards have meant that a re-assessment was required of the network's capacity and condition. A review of sewerage master plans - geographical blueprints for sewerage infrastructure - began in 1995 and in 2003 the last of these reviews was completed. They make a number of recommendations to improve the sewerage network.

The reviews identified sewers that need repairing or extension, treatment facilities and pumping stations that need upgrading, and misconnections to the stormwater system that need to be corrected. Some of these recommendations are already being carried out in response to urgent needs. For instance, improvement work in East Kowloon has begun to meet the demands from new residential developments there. The reviews also projected likely population growth and development plans up to 2016 to identify future demand that will have to be met.



Polluted stormwater affects the seafront of our harbour.
Polluted stormwater affects the seafront of our harbour.

The sewage strategy will help to improve water quality, but on its own it may not improve people's experience at the harbour's edge. This is because stormwater run-off is being polluted. Unlike sewage, which will be collected and treated, stormwater effluent is deposited, untreated, next to the shore.

Some people illegally use the stormwater system to carry their sewage to the sea, rather than hooking up to sewers. Others, such as certain restaurants, dump dirty dishwater down stormwater drains. And oil, animal faeces and other pollutants on the ground get flushed into the stormwater system whenever streets are cleaned or it rains.

Although stormwater pollution is not a new problem, it has become a greater concern in recent years. People's expectations of a better environment have coincided with increased development around the harbour and government plans to make better use of the harbour, such as the West Kowloon Arts, Cultural and Entertainment District. Enforcement against illegal connections has rectified many sewage-related problems, especially from the industrial and commercial sectors, but it is still not sufficient to stop all of the pollution going into stormwater drains. Most of the problems occur in older urban areas so in 2003, the EPD launched an in-house investigation to try to identify the contributions of various sources to the stormwater system. The study is focusing on Mong Kok, a typical older urban area.

At the same time, the department is exploring ways to control pollution from stormwater drains. A conference was held with environment officials from Australia and Canada who have experience dealing with this problem. The Hong Kong situation was considered to be much worse than in Sydney, Toronto or Vancouver because of the density of our development and the historical use of stormwater drains for wastewater disposal, but the session offered several ideas. Capturing the stormflow is one possible solution, although this could be expensive and difficult. Using less concrete paving was another, as this would allow the stormwater run-off to soak into the ground rather than flow into the sea. Education and legal measures were also discussed. Stormwater pollution may not have the impact on water quality that comes from sewers, but it can still spoil people's enjoyment of the harbour. The problem will need further study and discussion on the solutions and costs in coming years.



Apart from urban seasides, Hong Kong also has many beautiful beaches, enjoyed year-round by swimmers and surfers. These are bright spots in our water programme. Since 1986, when the EPD was established, a number of improvements have been made to ensure people can enjoy a healthy beach water environment. Sewage has been diverted away from beaches, nearby developments have been connected to the sewer system, and septic tanks have been required to be in good working order. As a result, the number of beaches with good water quality has increased from nine in 1986 to 23 in 2003.

Hong Kong's achievements are well recognised internationally. Following the release by the World Health Organisation of its Guidelines for Safe Recreational Water Environments in 2003, the British Broadcasting Corporation reported that while many Southeast Asian beaches were contaminated with sewage, Hong Kong was leading the way in its monitoring programme and its efforts to inform the public about beach water quality. Samples from each beach are collected on a weekly basis during the bathing season and graded as good, fair, poor or very poor, based on the likelihood of catching a swimming-associated illness. The public is informed of the results and if a beach is consistently very poor, it is closed.

This recognition for Hong Kong's beach programme confirms that we are meeting internationally-acceptable standards for managing recreational waters. These standards underscore our goals in all of our programmes, whether it is beach water quality, harbour sewage disposal, stormwater drains, rivers or streams. It will take investment and time to achieve similar successes in our other water bodies. But providing access to clean water for recreation, or simply the pleasure of enjoying a walk next to Victoria Harbour, remains a priority at the EPD. The value the community places on its water resources - a value that should become evident during the consultation on the HATS studies - will determine just how clean the waters throughout Hong Kong will become for future users.

Water Quality Improvements after Commissioning of HATS Stage 1
Water Quality Improvements after Commissioning of HATS Stage 1
Click to Enlarge
Map showing changes in dissolved oxygen (mg/L), NH4(mg/L) and E.coli bacteria (cfu/100mL) at 17 stations in the HATS enhanced monitoring programme between (Jan 2002 - Dec 2003 ) and (Jan 2000 - Dec 2001).

Beneficial recycling and reuse of wastewater.
Beneficial recycling and reuse of wastewater.

Hong Kong has a variety of water needs, from drinking and flushing to washing and irrigating. With fresh water in limited supply, sea water has often been used for non-potable purposes. But this source also has limitations. In 2003, the government took further steps to investigate the re-use of treated effluent to provide another, environmentally-acceptable source of water.

A scoping study for a pilot scheme in North District was conducted to identify possible premises for conducting trials and the best level of treatment. In technical terms, there is no reason why treated effluent could not be used for flushing, irrigation and other applications. The scheme would help also to identify non-technical issues such as the public's perception and acceptance of treated effluent. In the meantime a trial is planned for the cable car development at Ngong Ping on Lantau Island, when it is completed in 2005. The Mass Transit Railway has agreed to use the treated effluent for toilet flushing.



Hong Kong and Shenzhen share their environment and the pollution that contaminates it. In the 1990s the EPD and Shenzhen Environmental Protection Bureau co-operated in devising a plan to manage pollution in Deep Bay. That co-operative effort was then extended to Mirs Bay and, in 2003, both sides agreed on a plan for managing water quality there.

Mirs Bay.

Mirs Bay.


Mirs Bay has Hong Kong's cleanest waters and boasts hard coral and a diverse marine life. Since 1996 Hong Kong and Shenzhen officials have been gathering information on the pollution loads, assimilative capacity and likely impacts from future developments. This information was brought together in the new management plan, which recommends capping development below the assimilative capacity so as to minimise the impacts. The plan was endorsed in December 2003 by the Hong Kong-Guangdong Joint Working Group on Sustainable Development and Environmental Protection.


Looking Ahead

Consult the public on the best way forward for the Harbour Area Treatment Scheme.
Develop an agreed plan with the Shenzhen Environmental Protection Bureau on the first review of the Deep Bay Water Pollution Control Joint Implementation Programme to improve water quality in Deep Bay.
Implement a bioindicator monitoring programme in phases, to track the effects of pollutants on the ecological health of the marine environment in Hong Kong.
Commission in-depth studies to address stormwater pollution problems in West Kowloon.
Collaborate with the Water Supplies Department and Drainage Services Department on effluent reuse opportunities.


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