LCQ12: Water conservation

Following is a question by the Hon Chan Hak-kan and a written reply by the Secretary for Development, Mrs Carrie Lam, in the Legislative Council today (May 19):


The drought which earlier occurred continuously in the south-western part of the Mainland has aroused public concern about the stability of fresh water supply from the Mainland to Hong Kong.  There are views that Hong Kong should further promote the concept of water conservation, and the Government itself should take the lead in reducing wastage of fresh water as well as developing new water resources.  In this connection, will the Government inform this Council:

(a) which five government departments had the highest water consumption in the past three years, of their respective water consumption and expenditures on water charges (list out in a table);

(b) given that at present some tasks of government departments (e.g. watering flowers and washing streets, etc.) which consume relatively large quantity of water use fresh water, whether it will consider using reclaimed water and seawater instead, which has been filtered and purified; if it will, of the specific arrangements; if it will not, the reasons for that;

(c) whether specific targets will be set for water conservation within the Government; if so, of the details; if not, how it encourages various government departments to reduce the use of fresh water; and

(d) whether the study currently undertaken by the authorities on lowering the cost of producing reclaimed water will include assessing the implications of the relevant measure for future water charges, and apart from this study, what other measures are in place to develop new water resources?



To meet the long term demand for potable water in Hong Kong and respond more effectively to the unpredictable climate changes, the Government promulgated the Total Water Management Strategy in October 2008.  The Strategy puts emphasis on containing growth of water demand through conservation.  The aim is to prepare for contingencies and, in regard to the demand and distribution of water resources, enhance our role as a good partner of other municipalities in the Pearl River Delta region by doing our part in water conservation.  This will be beneficial to the whole region to cope with uncertainties, such as climate changes and low rainfall.

My reply to the four parts of the question of Hon Chan is as follows:

(a) The water consumption of the five departments with the highest consumption in the past three years is as follows:

Name of  Department
(million cubic
(million cubic
(million cubic
Leisure and Cultural  Services Department 11.1  11.9 11.8
Food and Environmental Hygiene Department   4.2 4.1 3.6
Correctional Services Department  4.0 3.7 3.7
Hong Kong Police Force 2.0  2.1 2.1

Drainage Services Department 




Under the current charging policy, policy bureaux and departments are exempted from water charges.  But "notional revenue" from their water consumption, computed on the basis of water tariff applicable to the public, is included in the Operating Accounts of Water Supplies Department (WSD).  The total notional revenue from water consumption of the government departments for the past three years is $450 million.

(b) The completed pilot scheme on using reclaimed water in Ngong Ping and Shek Wu Hui confirms that the scheme is technically feasible.  We are now considering using reclaimed water instead of potable water for non-potable purposes such as toilet flushing, street washing, vehicle washing and irrigation in Sheung Shui and Fanling.  The WSD together with other government departments have started to look into ways to lower the cost of supplying reclaimed water.  For the time being, we do not have any plan to extend the scheme to other areas since the use of reclaimed water is still under study.

(c) The specific targets for water conservation within the Government have two fronts.  For existing government buildings and schools, the WSD has commenced works on installing 23,000 water saving devices.  Upon completion in 2011, it is anticipated that it can reap an annual saving of 2 million cubic metres of potable water, 0.8 million cubic metres of seawater for toilet flushing and 1.5 million kilowatt-hours in energy consumption for treatment and delivery of the potable water and seawater.  As for new buildings, the Government issued an internal technical circular in April 2009 on green government buildings.  It requires all new government buildings to install water saving devices, such as low-flow water taps and dual flush cisterns.  In addition, we have implemented trial schemes on recycling grey water and harvesting rainwater for non-potable uses in a number of government buildings.  The WSD will review the standards adopted in these trial schemes in drawing up a set of comprehensive standards and technical guidelines to pave the way for wider use of recycled grey water and harvested rainwater for non-potable uses in future.

The Government has also planned to commission a consultancy study on water consumption practice of major government departments with a view to formulating for related facilities guidelines on saving water without affecting the level of public services.  We will start with reviews on the facilities of WSD as well as parks and swimming pools of Leisure and Cultural Services Department before gradually extending the review to other departments that are major water consumers.

(d) The current study on lowering the production cost of reclaimed water focuses on technical feasibility.  It does not cover impact assessment for future water charges.

Apart from conducting studies on production of reclaimed water, the WSD commenced in 2003 pilot plant study on application of reverse osmosis technology in desalination in Tuen Mun and Ap Lei Chau.  The pilot study, completed in 2007, confirms that the reverse osmosis desalination technology is technically viable in Hong Kong.  However, as the cost of desalination is much higher than Dongjiang water, huge investment in desalination is not cost-effective for the time being.  But we expect that advances in technology, such as improved efficiency in energy recovery systems and application of large diameter membrane in reverse osmosis process, will bring down the costs over time.   Therefore, we will continue to closely monitor the latest developments in desalination technology as a possible way to expand our sources of water supply in future.

The Government is also expanding the programme of seawater flushing to reduce the consumption of potable water for this purpose.  Main laying and infrastructural facilities are underway in Yuen Long, Tin Shui Wai, Tuen Mun East and Pokfulam to supply seawater for toilet flushing.  They are scheduled for completion in 2014.  We have also started planning for the expansion of seawater flushing supply system to Tung Chung on Lantau Island.

Ends/Wednesday, May 19, 2010
Issued at HKT 16:19