Determined were the volume of river sediment captured in a water reservoir at Wilcza Wola on the Łęg river. The water reservoir with 3.86 mln m3 capacity was put into operation in 1989. Silting measurements were performed after 10, 13 and 14 years of operation. Computed reservoir silting ratio were respectively: 13.08%, 15.79% and 16.20%. Samples of bottom deposits were collected to determine their physical and chemical properties. Determining of heavy metal concentrations may provide a basis for the sediment quality assessment and their potential applications in the environment after extracting from the reservoir bottom. Contents of harmful substances assessed in the sediments were compared with limit values permissible by the decrees of the Minister of Natural Environment Protection, Natural Resources and Forestry guidelines and criteria suggested in the foreign literature of the subject. The sediments from the water reservoir at Wilcza Wola are characterized by a low content of heavy metals. According to the Decree on soil quality standards [Joural of Laws, No.65, item 1359] none of the values established for the studied elements were exceeded. According to German guidelines threshold values of heavy metal concentrations in bottom deposits are between twice and thrice higher than those obtained in ...
Small water reservoirs are silted in the considerably shorter time in the comparison with average and large reservoirs. Considering the silting process de-silting work every dozen or years are carried out. Desilting of small water reser-voirs follows after the lapse of the considerably shorter time of operation than it to result can from the Hartung's criterion, according to whose reservoir not fulfils one's the function because of silting making up 80% of his origin capacity. The example is the reservoir in Krempna, which was desilted after eighteen years of operation, when his silting, determined for the help of the degree of silting, 41% carried out. The redevelopments of the reservoir were also executed during of de-silting works in 2006, reducing his capacity from 112 thousands m3 to 96,3 thou-sands m3. Execute the silting measurements in 2009 and stated that the degree ratio is equal 7,0 %. It was worked out the relationship between silting ratio and the time operation of the water reservoir in Krempna, definite on the basis established silting ratios of the reservoir in individual years before and after desilting. On the basis of this relationship was stated that the course of the silting process will take place ...
