Abstract
This article deals with the study of the operating mode of the Bukhtarma reservoir located on the Ertis river. Possible characteristics of future water use from surface water sources were taken as a basis for the modeling of hydrological series. Comparisons were carried out between the original and creatively modeled hydrological series of annual flows. The differences between them were established by the magnitude of the average standard errors of the original series of observations. Further, the options of calculations with an empty reserve are considered. The beginning of the calculation period was January 1, 2016, when the actual volume was Vn = 18.31 km3 (the dead volume of the Bukhtarma water reservoir). The duration of the calculation period is 20 years. In this case, the water supply was set in the range of 250-700 m3 / s, depending on the degree of filling the water supply and water supply. The rates were determined above or below the guaranteed return of water, the threat of filling the reservoir and the volume of water below the UMO mark. The volume of non-returnable water consumption, that is, the amount of water taken on the territory of China, is set in the range of 2-6 km3 per year. The calculations were made for the periods of different safety 25, 50 and 75%. Such periods were selected from the modeled range. Key words: water balance, mathematic modeling, river flow, water storage, modified series, water supply