A river changes its cross section, longitudinal profile, flow period, and pattern for several times, by means of scouring, sediment transport and deposition processes. For stabilization of the cultural and economical development of the adjacent areas to the river, it is essential to understand these processes. The Sistan River has undergone many morphological changes since 1956 to this date; and these changes have tremendous economical, political, and social impacts. Every year, by loss of the lands around the river, numerous damages imposed on the farmers and the environment of the region. In this study, the relocation of the Sistan River’s plan (since 1956 to this date) has been evaluated and analyzed. This was done using river edge sampling, sedimentological and geotechnical tests, and erodibility status of the edge along their reasons, by emphasis on soil engineering properties of the banks of the river in producing bank erosion. Evaluations show that incoherence, absence of drained shear strength, low aggregate levels, and weakness of the edge sediments (which are due to their newness, human interventions, natural harsh, and ignoring the measures necessary to prevent erosion of the river edge) have resulted in riverbank erosion and progression of the water current to the river concaves. Finally, to control river edge erosions and prevention of the river progression, possible solutions proposed based on local conditions.

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