2004 年 10 巻 p. 37-42
The purpose of this law is to protect life and property in the basin of urban rivers where severe inundation damage occurred or is likely to occur and where urbanization precludes the use of inundation prevention measures such as channel improvement, by designating such rivers and river basin as “designated urban rivers” and “designated urban river basin”, drawing up comprehensive river basin inundation prevention plans, constructing stormwater retention and infiltration facilities (to be carried out by river administrators), requiring obtaining permission for acts that severely hamper stormwater infiltration and taking other necessary measures.