Flood Risk Management in the Upper Vistula Basin in Perspective: Traditional versus Alternative Measures

Abstract

Flood-protection works carried out in the Upper Vistula basin since the late nineteenth century have been based on channel regulation and river embankment leading to fast evacuation of floodwater and a significant reduction in floodwater retention on the valley floors. Such a policy of flood-control management stemmed not only from the unfamiliarity with other methods and a generally technocratic approach to nature but also from the need to protect all arable land adjacent to rivers. This last motivation justified the approach in the early part of the period when farming provided for the existence of most of the society, but it progressively declined in significance with increasing urbanization of the region and economic development of the country. Flood-risk management based on the conventional methods has resulted in a severe degradation of the rivers’ ecological quality and increased peak discharges of flood waves recorded in the downstream parts of regulated and embanked river reaches. It is thus a priority to decelerate flood runoff and increase floodwater retention in less developed parts of the valleys in order to reduce flood hazard in spatially concentrated, urbanized areas along rivers. This paper presents alternative measures that either aim at reducing flood hazard at various stages of flood-wave passage through the region or serve to diminish flood risk by preventing development of river-adjacent areas, re-construction of bridges and cessation of the detrimental in-channel gravel mining.