抄録
The world population is expected to increases up to 8 billion by 2015. Most of the cities in the world are scattered around the fresh water resource. These cities and villages have their own interests and they constitute a power order. Therefore, we have been trying to harmonize these cities and villages in the usage of fresh water resource and the discharging of wastewater as well, by using an engineering means of water treatment.
The water environments science and technology should recognize the limit of fresh water resource for the sustainable development of the society, because the water service industries are the essential infrastructure of the community. In order to implement an appropriate risk management it is necessary to identify the goal of environmental management considering the social, natural and economical conditions. The energy dependent science technology should be reconsidered to be less energy and more resource conservation engineering means.
Water supply and sanitation technology is not the sanctuary for the society, therefore more comprehensive water management system should be developed by other sectors, such as food production industry, with concern.
