The River Vistula features various stages in the development of training measures that started in the 19th c. and aimed to convert it into a waterway. This study focuses on a foreland stretch between the towns of Skoczów and Puławy where the channel, originally meandering, sinuous or braided, has been shortened, narrowed and deepened as a result of engineering projects (Fig. 1, Fig. 2). Big differences were identified in the reshaping of the channel studied following the training measures, resulting in a reduced flood risk along those reaches where the channel depth was increased the most and in a considerable increase of this risk below Zawichost, where the measures were carried out last. The one morphological effect of the engineering that has the greatest impact on the discharge regimen is the increased channel compactness, especially along the originally meandering reaches (Fig. 3). The bank height along the deepened channel reaches increased by 3.5 metres on average since the project started. The changes in the channel morphology are conducive to faster flow rates (Tab. 1), which means that the bankfull discharge increases fast along the considerably deepened channel reaches with built-up banks. This rate is much slower along reaches with less ...
The paper summarises research into the geomorphological and hydrological effects of river training and improvement measures taken 45 years ago in the Nida valley. Positive and negative effects were identified, the latter including an increased flood exposure in half of the study area. The study aimed to find a feasible solution that would mitigate the flood risk. The valley is protected as a landscape park and belongs to a network of environmental corridors of national importance. Prior to the training measures, the River Nida, down from the confluence of the Czarna Nida and Biała Nida, ran in an entirely meandering channel with a minimal gradient causing long-term stagnation of the floodwater in the floodplain. The training and melioration measures were aimed at mitigating the flood risk, accelerating flood water drainage and draining part of the valley that had been used solely as meadows and pastures (Fig. 1). Vast wet marsh areas prone to cyclical channel avulsion were predominant along the braided reaches, such as near Umianowice (Fig. 2). As the engineering project started in the upper river course and continued downstream, the channel reaches directly below the newly deepened reaches became shallower. The process was documented by records of minimum ...
