Geomorphic Change Detection Using Multi-beam SONAR

Abstract

The emergence of multi-beam echo sounders (MBES) as an applicable surveying technology in shallow water environments has expanded the extent of geomorphic change detection studies to include river environments that historically have not been possible to survey or only small portions have been surveyed(Hazel, Grams et al. 2010). Much attention has been given to the topic of uncertainty propagation in the context of the construction of DEM and their use in geomorphic change detection studies, however little work has been done specifically with applying spatially varying uncertainty models for MBES data in shallow water environments (Wheaton 2008; Wheaton, Brasington et al 2010; Milan, Heritage et al. 2011). To address this need this report presents a review of literature and methodology of the pertinent steps to limit and quantify uncertainty in a geomorphic change detection study using data collected with MBES. Idaho Power Company (IPC) has provided data collected from MBES surveys from their ongoing development of a long-term monitoring program of sediment fluxes below Hells Canyon Complex. This data is used as a case study to illuminate and expand upon examples from the literature as well as to act as a template to demonstrate best practice methodologies for the use of MBES data for a geomorphic change detection study in river environments