The main problem in the operation of irrigation systems is to ensure the accuracy and reliability of measuring the main hydrometric parameters in managing water resources of irrigation facilities. When operating systems with pumping stations, it becomes necessary to measure a set of technological parameters, which can be divided into the following groups by type: hydraulic parameters (flow rate, fluid pressure, water flow in the channel), parameters of pumping units, linear-angular parameters (channel section length, channel width, gate movement, mixed parameters (clear area, flow depth, wetted perimeter length). Analysis of existing methods and instruments for measuring water flow for the rational use of water resources is used in all areas the volume of water taken from the water intake and supplied to the irrigation network. This task contributes to operational and control of pumping station parameters without hydrometric instruments at the stations themselves. The problem of organizing automated technological accounting of irrigation water at graduated hydraulic structures equipped with gates and operating in a flooded or backwater-variable mode is solved by new hydrometric methods with the integrated use of ultrasonic, acoustic, or float level gauges as part of modern microprocessor devices that convert water level readings at such structures into flow and runoff readings, according to the calibration characteristic each specific building. The article presents the recommended water metering devices for different hydraulic flow regimes and water quality. To speed up the process of measuring water flow in canals with flow rates of 1-10 m3 / s and large facilities of pumping stations with flow rates of 10-200 m3 / s, types of standard weirs, flumes of various profiles, and water measuring nozzles are recommended. According to the working formulas, changes in water flow are determined, taking into account the error of the gauging station and the indicated weirs.

For the conditions of Uzbekistan, it is necessary to maintain the reclamation condition of irrigated lands constantly and increase soil fertility. It is necessary to study the land reclamation condition in our region. An important factor is that collector-drainage waters are used for irrigation to pay off the shortage of water resources. The object of the study is the collector-drainage waters formed in the Republic of Uzbekistan. The article presents research on the method of statistical data processing, materials analysis, field research, and computer plotting curves and diagrams. As a result of the irrational use of collector-drainage waters, secondary clogging is observed in some areas. Data analysis was carried out from 2005 to 2020. The analysis of long-term studies shows that by 2020 there was a decrease in highly saline lands, which makes 83 thousand hectares. Whereas in 2005, saline lands made up 160 thousand hectares. Also, data analysis shows that areas with different mineralization are almost unchanged and need to develop scientifically based measures. The purpose and objectives of scientific research are to study irrigation with collector-drainage waters, their impact on the reclamation state of irrigation lands, and assess their suitability for irrigation. To increase the reliability of assessments of the quality of collector-drainage waters under various natural and economic conditions, it is recommended to use the relationship between water mineralization and the ratio of chlorine to sulfate. The dependence was built on the results of long-term data on the hydrochemical regime of collector-drainage waters. Estimates of our research have shown that at least 50% of the collector-drainage runoff is suitable for use in places of formation in Uzbekistan. Collector-drainage waters have mainly a sulfate type of salinity, and such waters with mineralization of 2-3 g/l, such waters with mineralization of 2-3 g/l can be used for repeated irrigation. To cover the shortage of irrigation water, drainage waters with increased mineralization by diluting them with fresh water will also be used for reuse.