Abstract
The Seta River is the only one natural outlet river of Lake Biwa. This paper examines the relationship between water level of Lake Biwa and discharge of the Seta River in historical years. Since there are no gauged discharge data in historical years, water level data are transformed into differences of outflow from inflow (Qout-Qin) using the relationship between water level and storage volume (H-V relation) of Lake Biwa. The results indicate that flow capacity of the Seta River was expanded after the dregging in Tempo years (1831-1833), and that there were no notable changes in flow capacity during Meiji Period (1874-1899).
