This study performed a literature review and analyzed the types, influencing factors, estimation formulas,and measurement techniques of the general scour in rivers. To improve the efficiency of existing scour depth measuring technologies, the existing measurement methods were evaluated, and the float-out device was identified as
the most effective scouring measurement tool. The float-out device was tested in a laboratory channel. Subsequently,
two measurement stations were constructed in the Mei river, Nantou County in Taiwan, on May 31 and June 1, 2016,
respectively, to collect scouring data during floods. The scouring process of a heavy rainfall event was successfully
observed on June 13, 2016. The float-out device proved suitable for measuring the scour depth in the Mei river. When the results of the field survey and measured data of the float-out device were compared, the float-out device was revealed to be an effective and efficient method of measuring riverbed scour. In the future, the applications of this monitoring technique can be increased. By increasing the amount of field data, the accuracy and localization of the scour estimation formulas can be improved.
Keywords: Upstream creeks, scour, wireless tracer.