As follows from a number of scientific works, water reservoirs are subjected to sedimentation at a higher or lower intensity requiring in consequence, after a time, desedimentation and renovation. There are several ways of desedimentation but the problem remains what to do with the sediments removed fro the bottom. This depends on the quality of bottom sediments, their ecological state and, first of all, of their chemical properties (especially of heavy metal content). Chemical properties of sediments may depend on the reservoir location whether in anthropogenic transformed territories or in ecologically undisturbed ones. In the paper results of works on chemical composition of sediments of some chosen small water reservoirs were compared. Subsequently these compared with fish pond and granulometric composition and its variability on bottom area, content of organic particles and presence of six basic heavy metals and their distribution in reservoir were examined. An attempt at mathematical relation between granulometric composition and heavy metals and between the percentage relation between organic particles and heavy metals was undertaken. The possibility of agricultural utilization of sediments after removal from the bottom was determined on the basis of the tables of permissible chemical soil pollution. ...
The storage reservoir “Besko” on the River Wisłok consists of two part: the main part, on the River Wisłok (volume of about 11 mln m3), and the other one, the side part, on the River Czernisławka – contributory of the River Wisłok (volume of about 3 mln m3). The research covered this side part of the reservoir. Physical properties of the bottom sediments were determined among others the granulometric composition according to Prószyński by use of two method: with addition of a deffloculant Na2CO3 and without, showing significant differences. Chemical properties were also determined among others the pH reaction, percentage content of organic particles and also presence of heavy metals – cadmium, copper, chromium, nickel, lead, zinc – and depending on it sediments were qualified for agriculture use. According to preliminary results the bottom sediments belong to first degree or not higher than second of chemical pollution what qualifies them for agriculture use and improvement of agricultural grounds. According to the accepted Polish standards either all agricultural crops (at zero pollution) or at the second degree of pollution with heavy metals, fodder crops, root crops can be cultivated or this grounds can be used as pastures. Increments of sediments in ...
Erosive processes are the limitative vitality of water reservoirs in catchment areas. Considerable quantity of the delivered erosion products to rivers are deposited in artificial barrage reservoirs. Qualification of the silting volume of small retention reservoirs in time of their operation and indication of the proper methods of silting forecast is a particularly essential engineering question especially in relation of the realized programme of small retention. The measurements results of silting of twelve small retention reservoirs being in the river-basin of the Upper Vistula were introduced in this paper. The determined mean silting degree of studied reservoirs carries out from 0,06 % to 6,38 %. Detailed silting forecast of four chosen water reservoirs was presented, two situated on water-courses with hydrological control - reservoirs Krempna and Maziarnia, and two situated on water-courses not included hydrological observations. The aim of the paper is appraisal of the possibility of silting forecast of small retention reservoirs by help of Gončarov’s and Šamov’s empirical formulas and on the basis of the determined intensity of silting according to Schoklitsch’s and Piečinov’s formulas. The capacity- inflow ratios - α, capacity-watershed ratios – C/W of studied water reservoirs were marked. This coefficients made it possible to qualify ...
The paper presents the effects of applied river engineering works and its influence on the changes of chosen hydraulics parameters along a reach of the mountainous stream. It was done by presenting the regime of the stream before and after river engineering works. The key parameters used for the hydraulics analysis were: stream velocity, shear stresses, stream power and finally the unit stream power. The research area was located in Polish Carpathians in the Beskid Sredni Mountains. The research stream is called the Cedron and the research reach is located close to Radziszow municipality around 30 kilometers from Krakow. The research was carried out in 2003 (before the river engineering works, after the major flooding in the region) and in 2004 after finishing river training works, which were mostly targeted to stop the bottom of the river and its banks from erosion. To carry on the research 6 cross sections were chosen where detailed velocities of running water were measured in the velocity profiles. Later the rest of analyzed hydraulics parameters such as stream power and shear stresses were calculated. The results were presented in graphical manner (fig. 1-4) and analyzed. In final conclusions it was pointed out, that all ...
