2020 年 8 巻 1 号 p. 5-12
Compared with the conventional HQ-curve method, the HK-curve method computes river discharge Q more accurately by considering hydrological data at water level H and water-surface slope i. In the analysis, the actual observed hydrological data during the flood is used, and the results indicated that the error of the computed Q by the HK-curve method for the observed value was less than almost 5%, while the error of the computed Q by the HQ-curve method occasionally exceeded 10%. Additionally, the results suggested that the HK-curve was almost identical to the one that considered the whole observed data from the river rising period to the river falling period via peak time during the flood although only the data in the period of drawdown were used. Thus, even when the data were observed only in the drawdown period of flood, the HK-curve method estimated highly accurate missing Q at the river rising period.