INVESTIGATION OF ACTUAL RETARDING IN OPEN LEVEE AND INSPECTION OF FLOOD CONTROL IN KITA-RIVER

Abstract

Kita-river has eleven open levees in Reinan region of Fukui prefecture. Retarding function of open levee contributes to flood control of city located on downstream. Kita-river has narrow basin area. It’s flow channel is short and steep slope. So if it will be rain falls heavily, water level rises and overtops open levee rapidly. Therefore, process of overtopping flood from open levee isn’t clearly. Thus, we measure overtopping flooded area, water level and flooded duration by using laser surveying data, water level loggers and time-lapse cameras. Furthermore, we comprehend retarding function of open levee using the measurements. As a result, overtopping flood from open levee have occurred seven times, we comprehend overtopping place and duration time clearly by measurements.