下水道整備が洪水流出現象に及ぼす影響
1988 年 1988 巻 399 号 p. 113-120
詳細
1988 年 1988 巻 399 号 p. 113-120
In recent years, there has been an increased in the frequency of floods in small river basins within the Tokyo metropolis. From the disaster-prevention perspective. This is a serious problem. This phenomena is a result of the progress of urbanization works in the basins, like the increased in the basin area drained by the urban sewerage system. Thus the volume of rainwater flowing into the urban rivers have greatly increase.
The aim of this paper is to clarify the cause of this phenomena. It is an analysis of the relationships between, the basin area served by the sewerage system and its rate of increase, with the characteristics of the flood discharge from the basins. The analysis is based on actual data of flood discharge and rate of increase of the area served by the sewerage system in a basin.
The importance of the extent of the area of a river basin served by a sewerage system, in addition to the amount of impermeable area, on the time of concentration has been clarified.
