The cathastrofical grand rainfall, which appeared on 2.08.2005 year in the amount of 70 l/m2 caused innudation in the basin of the Wielka Puszcza stream. The high flows caused numerous damages, for example: depresson of river bed bottom from 1 to 2m and broaden about 2–4 m. In many places the river banks, asphalt road, bridge and numerous trees were destroyed. After the innudation the assessment of destructions and also the biological construction in the river banks protection before the flows were made. It was found that, at the good biological construction of river banks there is not erosion. The best plant species for the biological construction are: Alnus incana, Salix alna, S. fragilis, S. viminalis, S. purpurea and other willow. If there are in biological construction the big flows don`t devastate the banks. Unadequate to biological construction are the forest trees for example Picea excelsa because they do not protect the river banks against the big flows. Assessment of damages made by big outflow for example: channel deepening and enlargement, reservoir sedimentation and damages of river banks by stones. The trees which were uprooted by big water created in some places water falls, and at its deep holes in ...
Erosion processes apart from distruction of upper layer of soil, influences morphology and hydrology of streams. Devastation of upper soil layer decreases basin retention what increases surface runoff, flood discharges and decreases low flows. Particularly bad damages in mountains basins are caused by heavy rains that have local extent but are very violent. The Wielka Puszcza basin is located on two natural regions: Podkarpacie Właściwe and Beskid Mały that belong to the Karpaty district. The basin area amounts 19,30 km2. Density of hydrographical network is 1,60 km⋅km-2, slope index 0,3102. Mean height attaines 507,5 m npm. The basin has forestry degree 81,65%, and indicator of forestry development 0,87. In the investigated basin prevail slopes above 30% (62,1%) and 20-30% (20,7%). It is lack of slopes of 0- 3%. The mean slope of the basin is 25,47%. In land use prevail forests (81,65%). There is 16,54% of arable lands, and grasslands cover 1,81% of the area. The cross sections of the channel and discharge intensity curves before flood and after flood that took place on 28 August 2005 were presented. Disasterous flows caused significant cross section area, lowering channel bottom of about 0,5 m. The change of flow intensity curve took ...
In the work there were presented results of investigations carried out in the framework of the research problem 09.10.04.04.03 concerning hydrological characteristics in the upper Soła river against the background of physiographical conditions, climate and use. Apart from physiographical characteristics the results of annual discharges measurements amounting 1,303 m3*s-1 at hydrometrical section closing the basin of an area of 37,525 km2, unitary runoff amounting 57 dm3*s-1*km-2 and runoff indicators 2,96 mm. ...
