Sedimentation rates and lifespan analyses in the “Kalimanci” reservoir

Abstract

Construction of reservoirs is a priority for providing sustainability of the water resources. In the Republic of Macedonia there are 23 big and over 120 small water reservoirs. On the other hand, erosion and filling the reservoirs with sediment is one of the main problems of reducing the lifespan of the reservoir with large environmental and economic implications. Reservoir sedimentation also provides valuable information on erosion intensity and sediment transport within a drainage basin. A reservoir can be considered as a large scale experiment, as the outlet of a giant erosion plot. The invent of the global navigation satellite system (GNSS), the bathymetric measurements of the sediment in the reservoirs became much easier. The measurements done with GNSS supported echosounder are completed much faster with considerable accuracy. Because the time needed for the measurements is much shorter then besides the measurements of the established profiles also some additional measurements can be done. Namely this new method gives the opportunity for total measurement of the reservoirs on profiles and contour measurement. The interest of this study is the Kalimanci reservoir. The reservoir was built in 1969 and up till now there are 13 measurements and therefore it is ideal for examination of the rates of deposition. It can be inferred that two mayor deposition periods exist, with braking point in the mid 80s. In comparison of the two periods the deposition is reduced by two and a half times.