宇治川流域の都市化と内水(2)-遊水池容量とポンプ容量-

Abstract

The Uji river basin of 13.9 km2 is mainly composed of mountains. The narrow and lowerplain of 2.2 km2 along the Uji river is used mostly as paddy fields and partly as urban areas.The urbanization is recently advancing mainly along the Uji river in spite of the dangeroustopographical condition from flood. Several flood prevention works had been hurriedly carried outafter severe disasters in 1975 and 1976.This paper discusses the storage capacity of a retarding basin in relation to pumping capacitywhich are required for absorbing the effects of future urbanization on flood. A new methodutilizing a functional expression for flood runoff hydrographs is introduced to find a quasioptimum capacity of drainage facilities before the detailed examination using a model for floodsimulation. It is emphasized, as one of the results, that the urbanization of this area is undesirablebecause the enlargement of the ponding storage capacity is limited by the topographical condition.