Scale invariance analysis of channel network width function and possible implications for flood behaviour

Abstract

An understanding of the scaling properties of precipitation and landforms (hillslopes, channel network) is, on its own, of theoretical and predictive significance. However, it is also expected that it should lead to the development of a physically meaningful flood scaling theory. The objective of this study is to identify catchment geomorphological scaling descriptors useful in establishing a criterion for similarity in regional flood behaviour. The focus is on the channel network. The nature of the scaling structure of the channel network width function is investigated. An attempt is made to determine the strength of the association between the scaling structure of the width function and at-site flood peaks. For catchments with drainage area greater than 200 km2, located east of Melbourne and the Great Dividing Range, this work established an association between the Levy index of the generators of the cascade structure of the width function and at-site flood behaviour. It is further suggested that such an index will be a useful candidate in the development of a criterion, which predicts similarity in regional flood behaviour.