A Study on the Possibility of Urban Wastewater Reuse for Fire Fighting and Recreational Activities

对于遭受地震袭击的城市，供水系统可能主要在交通方面出现故障，任何类型的用水需求都应该由河流、池塘、废水等其他水源来提供。这些区域水源不是流量而是存量，因为它们在没有额外补给的情况下很容易枯竭。虽然恢复供水系统将是逐渐增加的用水需求的主要供水方式，但作为应急准备工作，需要另一种利用区域存量的方法。然而，这些都没有从提高供水可靠性的角度来比较修复和前期工作的效果。本研究探讨了在地震应急情况下，如何构建除自来水厂外的区域水资源可获得性评价模型。地震后的用水需求仅限于消防和生活用水。在供需服从独立正态分布的条件下，定义了恢复供水和利用区域水源地的供需平衡概率。实例研究表明，事前配置应急水源与事后恢复供水工作系统之间的无差异曲线。提出了震后需水量预测方法，完善了城市震后消防和平时游憩用水再利用的规划方法。

For city struck by earthquake, water work system is likely to fail down mainly in transportation, and the any kind of water demand should be supplied by other water sources, such as river, pond, and wastewater. These regional water sources are to be evaluated as not a flow but a stock because they are easily exhausted without additional replenishment Although restoration of water work system would take main role of water supply for gradually increasing water demand, another way to utilize the regional water stock is required as preliminary work for emergency. However these were no discussion to compare the effect of restoration and preliminary works from a view point of improving water supply reliability. This study dealt with how to compose an evaluation model of availability of regional water stock other than water works in case of earthquake emergency. Water demands after the earthquake are restricted to fire-fighting and domestic water use. Probability of mass balance between gradually increasing water demand and supply both of restoring water work and using regional water stock sources is defined on condition that demand and supply obey independent normal distribution. Case study has shown indifference curve between the equipping regional water stock sources for emergency a priori and the restoring water work system a posterior. Water demand prediction methods after earthquake have also been proposed so to complete the planning methodology of urban water reuse for fire fighting after earthquake and recreational activities in ordinary time.