VIENNA, Sept. 7 (Xinhua) -- Climate change, future city development and sanitation services would be the three main topics of the 6th World Water Congress, which opened here on Sunday evening.

　　The traditional mode of water resource management must be changed, and most importantly, water recycling must be realized, stressed Glen Daigger, a delegate representative of the organizer International Water Association (IWA) on a press conference held before the opening ceremony.

　　He pointed out that the traditional concept of water consumption should be changed, and "the utilization of water resource must be more effective."

　　Darren Saywell, another delegate of IWA also noted on this press conference that nearly half of the population in the world can not receive enough sanitation services, and every day an average of 3,000 to 5,000 people die from that, many of which are children under five. Lack of sanitation establishments is a common problem. Therefore, it becomes one of the main topics of this World Water Congress.

　　About 3,000 delegates from different countries would attend this World Water Congress. During the formal session from September 8 to 11, there would be about 110 various meetings as well as a series of forums, lectures, symposiums and an exhibition about water technology.

　　Organized by IWA, the World Water Congress serves as a platform for exchanging views on water resource management and utilization strategy as well as other related technical issues. Through this platform, delegates from different countries would have the opportunity to know the experience and technology of other countries in water resource management and utilization, and to discuss related issues so as to find the right solution.

　　The World Water Congress is held every two years. The last one was in Beijing, 2006.