Dynamics of mid-channel bars in the Middle Vistula River in response to ferry crossing abutment construction

Anna Sosnowska

Abstract

Channel bars in alluvial rivers are integral structures in the river channels [1]. The reasons for non-migrating mid-channel bar development can be either channel planform variations or changes in channel width [2,3]. The nature of those processes can be dual: natural or activated. Irrespective of the reasons for mid-channel bar formation, the conditions in which they are formed are always similar. The emergence of bars in the river channel is always connected to high water flows which are characterized by high transporting potential. Not without a significance is the geological aspect of the river valleys. Valleys of rivers flowing in lowlands are composed of deep erosional base which is filled with alluvial deposits. Without such geological structure, the river would not have the possibility to adapt and reshape its channel in response to the flow dynamics.