The assessment of sediment amount transported by river based on indirect methods may lead to considerable errors. It particularly pertains to the assessment of transported suspended sediment quantity. In the paper methods are presented of determining the amount of load transported by the river and supplied to the water reservoir at Krempna on the Wisłoka river. The quantity of load flowing into the reservoir determined on the basis of field measurements was assumed reliable in the assessment of applied computational methods. On the basis of results of the multi-annual investigations on the silting processes, the authors, set a value of β-parameter using the results of the silting volume measurements and load transport computations during the subsequent years of the reservoir’s operational period. The sediment trap efficiency of the reservoir determined on the basis of transported sediment mass computed according to bathometric measurements and silting surveys ranges between 65% in 1998 and 50% in 2005. The determined sediment trap efficiency on the basis of the results of calculations by the DRUSLE method is on about 30% larger than the sediment trap efficiency value calculated on the basis of bathometric measurements. The amount of sediment transport computed by the MUSLE method is ...
Despite the various categories of defining the life of water reservoirs, the notion life of reservoir most often relates the period of the operation to such silting degree that makes impossible the realization of the tasks of the reservoir. In this work it was show the change of the value of the silting degree and sediment trap efficiency of chosen reservoirs and was estimates the time after which small water reservoirs will be silted in 50%. This is the period, which by Pitt and Thomson [1984] is defined as HLT, i.e. half-life time. The following reservoirs were chosen to studies: Krempna on the Wisłoka river, Zesławice on the Dłubnia river and Cierpisz on the Tuszymka river. The elaborated silting forecast of the change of the silting degree, make by the Gončarov's method [Wiśniewski, Kutrowski 1973], made possible the qualifi-cation the HLT silting time of small water reservoirs. It was stated that the life of studied reservoirs carried out from 17 to 40 years. The differentiation of the HLT value results from the hydraulic conditions of the inflow and flow through the re-servoir of the water and sediment which one can characterize in the very general method using the sediment trap ...
The results of the calculations of the sediment trap efficiency of small reservoirs were introduced in the work. The sediment trap efficiency was appointed the symbol . Nine small reservoirs located in the Upper Vistula river basin were chosen to analyses. This efficiency became determined on the basis of the sediment balance and compared with the results of applied Brune's method and its modification, worked out by Gill, Heinemann and Jothiprakash and Garg. It was stated that the possibility of the use of these methods to delimitation of the initial sediment trap efficiency of small reservoirs existed. The initial concerns to the beginning of operation. These methods can have the use in the case of the small reservoirs the whose capacity-inflow ratio is larger from 1%. Also it was stated, that the results of the calculations of the sediment trap efficiency in the successive years of the operation of small reservoirs executed using Brune's method and Gill's, Heinemann's and Jothiprakash's and Garg's formulae they do not represent real value of , determined on the basis of the sediment balance. Estimated methods can not the be used to the qualification of the sediment trap efficiency of small reservoirs in ...
