Abstract
Many small urban tidal rivers in Japan lack natural water sources. During storm period, untreated water flows into these rivers through a combined sewer system, causing pollution loads. This study aims to characterize the water quality and pollution load in a small urban tidal river during storm period, focusing on the discharge, water quality and pollution loads by classifying storm period into three phases: flood, transition and tide phase. The results indicated that most of the discharge, the organic pollutants, and the suspended solids were observed especially in the flood phase. Also, in the transition phase, there were no significant differences in water quality at different depths. Besides, dissolved oxygen changes in the transition and the tide phase could be explained by different factors.
