LCQ5 : Study on desalination

    Following is a question by the Hon Lui Ming-wah and a reply by the Secretary for the Environment, Transport and Works, Dr Sarah Liao, in the Legislative Council meeting today (January 10) :


     Further to the completion of the one-year pilot study on desalination in Tuen Mun, the Water Supplies Department is now conducting another study in Ap Lei Chau.  In this connection, will the Government inform this Council:

(a) of the findings of the pilot studies on desalination conducted in the two places mentioned above;

(b) of the per-cubic-metre cost of desalination and the respective percentages of various expenditure items (such as construction and maintenance of plants, electricity, osmosis membranes and chemicals used for removing impurities and disinfection, etc) in relation to such cost; and

(c) whether it plans to build a desalting plant using the reverse osmosis technique to help solve in the long run the problem of potable water supply in Hong Kong?


Madam President,

(a) Water Supplies Department completed a one-year trial operation of the pilot desalination plant at Tuen Mun before end-2005.  Preliminary test results indicate that seawater desalination using reverse osmosis technology is technically feasible in Hong Kong.  The plant has subsequently been relocated to Ap Lei Chau since early 2006 to try out different coastal water quality for one other year.  More test details will be available in the final report to be issued upon completion of the pilot desalination study scheduled for mid-2007.

(b) Based on the initial findings of the pilot desalination study conducted at Tuen Mun, the unit production cost of the desalinated water is estimated to be $7.8 - $8.4 per cubic metre (at January 2005 price level), with the breakdown on the percentages of various expenditure items as follows:

Construction Cost                 52%
Electricity                       20%
Membrane Replacement               3%
Staff                              2%
Chemicals                         10%
Miscellaneous                      7%
(repairs and maintenance)
Contingency                        6%
Total                            100%

(c) Water Supplies Department is undertaking a consultancy study scheduled for completion in end-2007 to map out the long-term strategies and formulate implementation plans for the Total Water Management (TWM) programme in Hong Kong.  Under the TWM study, we will examine the distribution of various water resources and their cost of supply (including Dongjiang water, reclaimed water, desalinated water, local yield etc.).  We will also map out the long-term strategies on the effective use, development and the share of supply of various water resources for meeting the future demand.  The Government has no definite plan on the use of desalinated water at this stage.

Ends/Wednesday, January 10, 2007
Issued at HKT 13:18