Bankfull hydraulic geometry; the role of in-channel vegetation and downstream declining discharges in the anabranching and distributary channels of the Gwydir distributive fluvial system, southeastern Australia

► Downstream hydraulic geometry of the Gwydir Distributive Fluvial System. ► Bivariate hydraulic geometry exponents are outside previously reported ranges. ► Multivariate hydraulic geometry shows unusual proportion of energy expended on banks. ► We collate evidence supporting contention that in-channel vegetation is responsible.