Features of the construction of canals in half-cut-half-fill

¹ "Tashkent Institute of Irrigation and Agricultural Mechanization Engineers" National Research University, Tashkent, Uzbekistan
² Consultant Engineer for the Proj. improvement of Water Resources Management in South Karakalpakstan, Uzbekistan

^* Corresponding author: bakiev1947@rambler.ru

Abstract

This study examines the construction features of the Bustan Canal in the Republic of Karakalpakstan, designed with a half-cut-half-fill method to optimize water supply and drainage capabilities. Given the region’s high groundwater levels, canals were constructed in trenches, serving dual purposes of irrigation and open drainage to mitigate flooding risks. The primary goal was to enhance the canal’s efficiency coefficient to 0.85 by applying concrete lining to its slopes and bed, transitioning from mechanical to gravity irrigation sourced from the Tuyamuyun Reservoir on the Amu Darya River. The study highlights the advantages of using excavated soil for embankment construction, which significantly reduces transportation costs. Physical properties and granulometric composition of the soils were analyzed in accredited laboratories, confirming optimal compaction densities between 1.72 g/cm³ and 1.77 g/cm³ at moisture contents ranging from 17% to 20%. The findings underscore the importance of this canal system in supporting agriculture over an area of 100,000 hectares, enhancing water management practices in Southern Karakalpakstan.