A field study on revival of covered rivers in Tokyo's 23 wards

水是有限的资源，是生命不可缺少的资源。然而表面外流降水增加的数量没有增加,渗水的负载到河边的增长,和河水的流动数量是永恒的此外,减少了在城市里部分时,对应的水是城市化的进展,因为担心服用水需求数量增加和减少的趋势在河里,水的供应源。有效利用降水、隧道泉水和现有水循环设施等的社会基础设施更是需要这样的背景。然后，需要了解该地区的水预算，以明确维护政策。

Water is a limited resolute, and an indispensable resource for life. However the amount of the surface outflow at precipitation increases by no water penetration side's having increased, the load to the river grows, and the flowing quantity of the river when it is eternal has decreased in the city part Moreover, the correspondence when running short of water is feared to the progress of urbanization because the taking water demand increases and it is in the decreasing tendency flowing quantity in the river that is the supply source of water. The social infrastructure to use precipitation, tunnel spring water and existing water circulation facilities, etc. effectively is needed more than such a background. Then, it is demanded to understand the water budget in the region to clarify the maintenance policy.