Being a small and densely populated city, Hong Kong has always been in lack of natural fresh water resources, and the meagre amount of water collected at the gathering grounds in Hong Kong can hardly meet our demand.  Fortunately, we have the support of the Central People’s Government.  Since 1965, Hong Kong has been importing Dongjiang (DJ) water from Guangdong Province.  The supply quantity has increased several times and DJ water now accounts for 70 to 80 per cent of Hong Kong’s total water supply.  As DJ water is the major source of water for our daily lives, I joined 18 Legislative Council (LegCo) members in a two-day duty visit by LegCo’s Panel on Development to the DJ river basin a couple of days ago (14 to 15 April) to learn more about the DJ water supply facilities and their water quality monitoring and control work together with my colleagues.  I would like to express my heartfelt gratitude to the Mainland authorities for arranging the visit.  I believe that the visit has enabled LegCo members to know more about the operation of the DJ water supply system and the enormous efforts of the Mainland authorities in safeguarding the quality of DJ water, as well as enhanced mutual communication and understanding.

We had a packed schedule and visited a number of key facilities in a short period of time, including the Xinfengjiang Reservoir in Heyuan, the Green Way in Huizhou, the Dongjiang River Basin Water Quantity and Quality Monitoring and Control Centre, the Taiyuan Pumping Station in Dongguan, the Bio-nitrification Plant at Shenzhen Reservoir and the Shenzhen Reservoir.  I would like to take this opportunity to share with you that DJ is not only the major source of fresh water for Guangzhou, Shenzhen, Dongguan, Huizhou, Heyuan, but also has the important task of supplying water to Hong Kong, serving a total population of over 40 million.  With average annual per capita water resources of only 1 100 cubic metres, the DJ river basin is regarded as an area of water scarcity according to international assessment standards.  Therefore, Guangdong Province implemented a DJ River Basin Water Resources Allocation Scheme, which co-ordinates the annual flow in the river basin according to the total amount of allocated water resources, so as to ensure a reasonable and efficient usage of the limited water resources.  In addition, the water resources development and utilisation rate of the DJ river basin has already reached 28.6 per cent, which is very close to the “safety red line” of the total development ceiling rate of 33.3 per cent, indicating a fairly tight supply of water resources.

Located in Heyuan, Xinfengjiang is a tributary of DJ which is a section of the Pearl River.  Built in 1958, the Xinfengjiang Reservoir (also known as Wanlu Lake) we visited on the first day is the largest artificial lake in Guangdong Province with a rainfall catchment area of 5 734 square kilometres.  It has a lake surface area of about 370 square kilometres which is about 30 per cent of the size of Hong Kong, and a storage capacity of about 13.9 billion cubic metres (equivalent to 50 High Island Reservoirs).  As we could see, the lake is as calm as a mirror.  The LegCo members were all impressed by the pristine water quality of the lake, and its important mission of flood control and water supply.

Development sacrificed for water quality

The Mainland authorities always attach great importance to the ecological conservation of Wanlu Lake, with the aim of consolidating and enhancing its water quality.  During the visit, Heyuan officials told us that they had to give up some local business and development projects so as to protect the water supply area.  For instance, more than 100 pig farms and food premises in Heyuan which would affect the water quality of Wanlu Lake have been shut down.  More than 200 mining hills have undergone rehabilitation and greening.  They have also been taking forward various environmental infrastructures in full swing such as the sewage treatment plants along the DJ and associated pipe networks as well as landfills.  To safeguard the precious water resources, the authorities have also set a high threshold for environmental protection.  All industrial projects have to be confined in a designated industrial park with centralised treatment for industrial wastewater, while projects which do not meet the wastewater standards will be rejected.  In 1994, the Heyuan Municipal People’s Government turned down a multi-billion dollar joint venture project with a Japanese enterprise for building Asia’s largest paper pulp mill.  Other similar projects which have been shelved include a leather factory worth tens of millions of dollars.  These examples show that a lot of development opportunities have indeed been sacrificed so as to safeguard water quality.

On the first day, we also visited the Dongjiang River Basin Water Quantity and Quality Monitoring and Control Centre of Guangdong Province where we were briefed that the Water Resources Department of Guangdong Province invested a total of $98.85 million in 2014 to construct the DJ Water Quantity and Quality Monitoring and Control System to ensure the effective implementation of the DJ River Basin Water Resources Allocation Scheme.  The system establishes a modernised platform for water quantity and quality monitoring, allocation and management through primary data collection, information integration, network environment construction and software application, which enables effective monitoring and management of the valuable DJ water resources.  Through the video surveillance platform and software, the Centre can obtain real-time information regarding the protection and usage of the water in the river basin, and make appropriate adjustments.  The LegCo members were highly interested in the monitoring and control system, and had in-depth exchanges and interactions with the briefing officials.

Dedicated aqueducts separating clean water and sewage

We visited the Taiyuan Pumping Station in Qiaotou Town, Dongguan on the second day of our visit.  Built in 1998, it has a designed capacity of 100 cubic metres per second (i.e. 3.153 billion cubic metres per year) and a pumping head of 11 metres.  We were arranged to visit the intake point, pumping station, etc. of DJ water supplied to Hong Kong, and were briefed by local officials on the general situation of the Dongjiang-Shenzhen (Dongshen) Water Supply Scheme  and the operation of the DJ Water Supply System for supplying water to Hong Kong.  The officials advised that the most important part of the Dongshen Water Supply Improvement Works was the construction of a 59-km dedicated aqueduct from the Taiyuan Pumping Station to the Shenzhen Reservoir.  The aqueduct includes a water tunnel of about 22 km and a dedicated aqueduct of about 37 km, forming a “closed” water supply system with pumping stations, channels, tunnels, reservoirs and dedicated aqueducts for the separation of clean and dirty water, while raw water from DJ is conveyed directly from the intake point at the Taiyuan Pumping Station to the Shenzhen Reservoir to maintain the premium quality of DJ water supplied to Hong Kong.  The dedicated aqueduct has a designed supply capacity of 2.4 billion cubic metres per year, of which the volume of water supplied to Hong Kong can be up to 1.1 billion cubic metres per year while the rest is allocated to cities and towns along the aqueducts according to quota.  It shows that Hong Kong has a large share of DJ water consumption.

Water quality monitoring and data exchange

The quality of DJ water is an issue of concern to both the LegCo members and the public.  In fact, the Guangdong authorities have carried out a series of works to enhance the protection of DJ water.  These include moving the intake point of DJ water to extract water of better quality to supply to Hong Kong; commissioning a bio-nitrification plant at the Shenzhen Reservoir to enhance the quality of raw DJ water before it enters the Shenzhen Reservoir; conveying DJ water directly from the Tai Yuen Pumping Station to the Shenzhen Reservoir through the dedicated “closed” aqueducts; undertaking various sewage diversion and interception works at the DJ tributaries; setting up closed-circuit television monitoring systems in the periphery of the Shenzhen Reservoir to strengthen control over untoward incidents that affect water quality; as well as implementing the DJ Water Quantity and Quality Monitoring and Control System to facilitate real-time monitoring of the DJ river basin water resources.  I believe that after this visit, the LegCo members will have a better understanding of the efforts of the Mainland authorities in safeguarding water quality.

The quality of DJ water is being closely monitored around the clock.  Should any anomaly in its quality be detected, the Water Supplies Department (WSD) will immediately step up the monitoring of water quality, regulate the procedures of water treatment plants in the downstream, and promptly liaise with the Guangdong authorities concerned to find out the causes.  In addition, Guangdong Province and Hong Kong will also exchange detailed DJ water quality monitoring data on a regular basis.  The Guangdong side will periodically provide the WSD with detailed water quality monitoring findings from the Tai Yuen Pumping Station (i.e. the intake point of DJ water supplied to Hong Kong) and the Shenzhen Reservoir, while the WSD will provide the Guangdong side with the monitoring data of DJ water received by Hong Kong from time to time.  In fact, all raw water, be it DJ water or rainwater collected from local reservoirs, will be conveyed to the WSD’s water treatment works for water treatment.  All water treatment works are equipped with online water quality monitoring systems to monitor the quality of raw water entering the treatment works so as to ensure the safety of water supply at all time.

As the saying goes, “A thousand miles begins with a single step”.  The successful conclusion of this DJ visit was attributed to the close communication and discussions in recent months between our colleagues of the Development Bureau and the WSD, and the relevant authorities of the Guangdong Provincial Government, including the Water Resources Department, the Environmental Protection Department and the Hong Kong and Macao Affairs Office.  Their efforts have enabled LegCo members to learn about the measures taken by the Guangdong authorities in safeguarding the quality of DJ water supplied to Hong Kong, understand the operation of the DJ Water Supply System and observe the DJ water quality on-site.  They could also exchange views directly with the Guangdong authorities on matters of mutual concern, so as to address some of their previous misgivings.

“When it comes to people’s livelihoods, nothing is too trivial”.  To ensure the provision of a safe and reliable supply of drinking water to the public, we always strive to do our best in monitoring the quality of both local and imported water.  I hope that LegCo members will have more duty visit opportunities on the Mainland in future, so as to have open and frank exchanges on various issues to enhance mutual trust and understanding.