The article is devoted to the study of the influence of the damless water intake on the hydraulic and alluvial regime of the river, the channel of which passes through easily washed out soils. The analysis of the dynamics of the river bed morphometry and hydraulic elements of the flow in the area of the damless water intake is carried out. As a result of the analysis of the data of long-term field studies and hydrometric measurements at the closest section to the damless water intake and in the area of the damless water intake of the Amudarya River, functional relationships were established between the morphometric parameters of the channel and the hydraulic parameters of the flow. The dynamics of the Shezi coefficient, hydraulic resistance, and the channel roughness coefficient in connection with the hydrodynamic characteristic of the flow are established.

The article gives the reason for the formation of Lake Aydarkul, according to which Lake Aydarkul began to form, starting from the catastrophically high year of 1969 - as a result of the discharge of 21 cubic kilometers of Syrdarya waters from the Shardara reservoir. The area of the lake system reached 2000 km2, salinity of water – 2 – 4 g/l. In the next decade, there was a drop in the water level in the lakes and deterioration in its quality. By 1978, the depth decreased from 25 to 20 meters, and salinity increased to 7-8 g/l. An analysis of the available materials devoted to this problem showed that the water surface of Aydar and Tuzkan lakes extends from west to east for more than 180 kilometers, and the adjacent chain of Arnasay lakes stretches from north to south for more than 70 kilometers. The reason for the salinity of Aydarkul was indicated - before the commissioning of the Shardara reservoir, salt lakes were located on the site of the lakes, and only in the Tuzkan Basin fed by the Kly River was a shallow salt lake. The problem can be solved by transporting an additional volume of water to the lower reaches of the Amudarya, which will improve the ecological situation in the Aral Sea region, provide, over time, the formation of fresh lakes and create a water management system Syrdarya - Aydarkul - Zarafshan - dead lakes - Amudarya. This system can serve the broad development of fisheries, and also contribute to the opening of new agricultural areas of the republic, while creating several hundred new jobs. A method is recommended for solving an important national economic task of the industry. It is proposed that for the formation of the water system Syrdarya – Aydarkul - Zarafshan - “dead lakes” – Amudarya – Priaralye, it is necessary to design and build the main canal with several sections of a length of about 250 km, each of which communicates with the lake of the above system, will provide gravity communication of three large rivers of the Aral Sea basin. It is proposed to design the main canal with improved lining, which will provide high efficiency, which, in turn, will reduce the filtration coefficient and contribute to an increase in water intake for the needs of the national economy, expansion of irrigated areas and the development of fisheries in the region, and improvement of the ecological situation in the Aral Sea region.

The paper analyzes the dynamics of channel processes in the channel of the supply channels of pumping stations. The results of field studies of the condition of the channel environment in the supply channels of the pumping stations were studied. Based on the results of field inspection and research of the supply channel, recommendations were developed to improve its operation. Analyzed and summarized the results of surveys of the hydraulic and alluvial sediment regimes in the channel of the supply channels. The results of the effects of sediment entry into the chambers of pumping stations are presented. The dynamics of reducing the capacity of the supply channels of pumping stations were analyzed; The effect of sediment on the impellers and other stationary parts of pumping units, leading to a decrease in their performance; Recommended new layout schemes of the route and sedimentation tanks of the supply channels of pumping stations; A device of additional structural elements is proposed that allows improving the operating conditions of the supply channels of pumping stations.

The Syrdarya water basin association is an intergovernmental coordinating organization which is part of the interstate commission (ICWC) on Aral Sea rescue in the role of "Executor". Transboundary waters are distributed to Kyrgyzstan, Kazakhstan, Tajikistan and Uzbekistan with the help of hydraulic structures within the association. In order to avoid disagreements between "water consumers" in distributing the transboundary waters of the Syr Darya, the operating organization should have up-to-date information on the amount of water flowing into Syr Darya River and on consumption of water distributed among users. This article describes the experience of the BWO "Syr Darya" in improving data collection and management of hydrosystems within its balance.

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