Assessing Hazardous Manifestations of Horizontal Channel Deformations in Rivers of the Ob–Irtysh Basin

Abstract

Bank erosion is a hazardous manifestation of channel processes, which are widespread on the rivers of the Ob–Irtysh basin and pose both real and potential danger. The most widespread form of channel transformation in the rivers of the basin is the development of channel bends, bends of branches of a bifurcated channel and bends of branches of floodplain–channel bifurcations, as well as branches of channel (insular) bifurcations due to bank erosion, which leads to a directed change in their morphological parameters. The channel stability is a key characteristic for assessing the hazard of channel processes. The largest rivers of the basin (the Ob and Irtysh) have relatively stable channels, corresponding to a moderate hazard. The medium and large rivers, in which the hazard of channel processes was evaluated by points, show a relatively low level (mostly, 1–2 points), which increases downstream to reach 3 points in the lower parts of large rivers (the Tom and Chulym). Overall, the intensity of shore erosion, and, accordingly, the hazard of horizontal channel deformations, in the rivers of the Ob–Irtysh basin decrease northward and toward the Ob–Irtysh interfluve. The obtained results can be used for the safe use of water ways and near-river areas as well as for the effective management of hazardous manifestations of channel processes.