Assessment of Chimkurgan water reservoir sedimentation processes

Abstract

Uzbekistan is an inland country with very dry summers and cold winters. The main course of the economy is agriculture. There are two basic kinds of agriculture in terms of irrigation: rainfed and artificial irrigation systems. Therefore, in long dry summers it is reasonable to build water reservoirs to keep enough water resources for vegetation period. Because of sedimentation transport water reservoirs sometimes quickly filled with sediment. Estimating the effects of potential sediment accumulation in reservoirs is an important element in the planning of the dam project. Sediment accumulation in a reservoir may reduce the useful storage of water in this reservoir, change the water quality near the dam, increase flooding level upstream of the dam due to sediment aggradation, influence the stability of the stream downstream of the dam, affect stream ecology in the dam region, etc. This article provides a correlation between the reservoir volume reduction from the bottom to a given level, based on the amount of water flowing into the Chimkurgan reservoir and the river basin monitoring data. Based on the results of observations and calculations, the current state of the reservoir was formed on the basis of GIS tools. In the first step we constructed a flow duration curve, which is the cumulative distribution curve of the stream runoff passing the dam.