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The scarcity of water can result in a direct conflict between the protection of aquatic resources and water use. For many agencies, environmental flow (EF) methods are essential in environmental impact assessments and in the protection of important fisheries resources. The objective of this paper is to compare selected hydrological and hydraulic methods and determine the scientifically acceptable and cost-effective way to environmental flow within a section of a mountain river with high naturalness, on the example of the Wisłoka. In this paper, environmental flow was calculated using conventional hydrological methods: Tennant’s, Tessman’s, flow duration curve and hydraulic methods, wetted perimeter method (WPM) and method based directly on ichthyofauna habitat requirements (spawn and migration). The novelty is the combined use of the hydraulic and hydrological methods which relates to flow hydraulics based directly on ichthyofauna habitat conditions. The hydraulic methods provide lower values of environmental flow in comparison with the hydrological methods. The key issue in the use of the hydraulic methods is the choice of criteria. The development of the required set of parameters while taking into account their seasonal nature shifts the method toward habitat modeling methods. However, the scope of habitat requirements of ecosystems must be defined, including the set of aquatic organisms and watercourse type before a hydraulic method may be widely used. Being generally low-cost and simple, the methods presented in this paper can be applied in the water management legislative process.

The aim of the study was to analyze the possibility of using selected rainfall-runoff models to determine the design hydrograph and the related peak flow in a mountainous catchment. The basis for the study was the observed series of hydrometeorological data for the Grajcarek catchment area (Poland) for the years 1981–2014. The analysis was carried out in the following stages: verification of hydrometeorological data; determination of the design rainfall; and determination of runoff hydrographs with the following rainfall-runoff models: Snyder, NRCS-UH, and EBA4SUB. The conducted research allowed the conclusion that the EBA4SUB model may be an alternative to other models in determining the design hydrograph in ungauged mountainous catchments. This is evidenced by the lower values of relative errors in the estimation of peak flows with an assumed frequency for the EBA4SUB model, as compared to Snyder and NRCS-UH.

The aim of the article is to show how the fluvial processes in rivers and their valleys can support wetland restoration activities. The exemplary objects were localized in the Upper Vistula Basin (Poland) and dealt with riverbed stability, channel capacity as well as revitalization of rivers with their valleys regarding wetland restoration. All of the mentioned parameters depend on the intensity of fluvial processes in rivers, especially meandering, anastomozing or braided. Rivers always tend to reach the state of hydrodynamical balance reflecting the actual river dynamics. The nature of channel transformation is quite complex. For example, the curvature of natural river increases proportionally to the transported load alimentation and inversely to the slope of the river. The human-modified rivers also tend to increase the curvature of their channels. Interestingly, all rivers create wetlands in the areas naturally connected to the main channel. Those wetlands are regularly watered by flood events. As a result, the areas with wetlands are a perfect natural environment for fauna and flora. River channels which are situated close to such an environment are also rich in fish and invertebrates. Wetlands in mountainous areas are rare or unique unlike in lowlands where they are more likely to be found. The channel incision reduce a possibility of wetland formation in the river valley, especially after bank enforcement. The presented case studies are the effect of different projects running by the Department of Water Engineering and Geotechnics, the University of Agriculture in Kraków on the rivers and streams: Vistula, Nida, Porębianka, Czarny Dunajec. These rivers differ in many aspects; however, each of the them is located in an area where wetlands or wetted areas are likely to appear. Among the described rivers are lowland and mountain rivers. Some of them are managed according to the European Water Framework Directive, i.e., in a close-to-nature manner.

The use of the Mike11 one-dimensional (1D) hydraulic model, together with official hydrology, represents a standard approach of the National Water Management Authority (NWMA) in Poland for flood mapping procedures. A different approach, based on the hydrological Event-Based Approach for Small and Ungauged Basins (EBA4SUB) model and the Flood-2 Dimensional (FLO-2D) hydraulic model has here been investigated as an alternative procedure. For the analysis, two mountainous rivers in Poland were selected: Kamienica Nawojowska is characterized by a narrow valley, while Skawinka has a broad valley. It was found that the flood zones can enormously differ locally, with larger zones generated by the Mike11/NWMA model in some cases and by the EBA4SUB/FLO-2D model in other situations. The benefits of using the two-dimensional (2D) model are consistent in areas without drainage and where the connection to the main channel is insufficient. The use of 1D modeling is preferred for the possibility of mapping the entire river network in a short computational time.

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Nadzwyczajne zdarzenia powodziowe wywołują dyskusje o skuteczności ochrony przeciwpowodziowej. Składają się na nią między innymi pytania o przepustowość koryta i międzywala czy też o priorytety w ochronie mienia i życia ludzi oraz w ochronie przyrody. Dotychczasowy model rozstrzygania tych kwestii wymaga nowego spojrzenia uwzględniającego zasady zrównoważonego rozwoju. W pracy podjęto się sprawdzenia, czy potencjalny konflikt pomiędzy ochroną przeciwpowodziową a ochroną przyrody możliwy jest do rozstrzygnięcia przy wykorzystaniu metod inżynierskich bez naruszania siedlisk cennych z przyrodniczego punktu widzenia.