ANALYSIS OF HYDROLOGICAL CYCLE IN THE AZUMA UPRIVER EXPERIMENTAL BASIN

Consciousness of the environment has raised in recent years. Many municipality corporations began conserving and reviving the ecological river front in urban areas which was deteriorated by urbanization. The first procedure for the river front conservation is to increase the ordinary water discharge of urban minor rivers, and the basic study for that is to clarify the hydrological cycle of such river basins.The present paper analyses the hydrological cycle in terms of groundwater runoff, direct runoff and groundwater storage in the Azuma upriver basin during 76 days in 1996, using the daily hydrological model for an urban basin which was presented by Ando et. al.(1982). The simulation resulted in approximation to the observed runoff hydrograph and the groundwater storage which was derived from the measured groundwater level. This paper also predicts the runoff hydrograph in the same period using the same model on the supposition that houses infiltration facilities are set in this basin. This simulation demonstrated that the groundwater runoff was increased and the direct runoff was reduced, that effect on restoring the ordinary water discharge.