SYSTEM APPROACH IN RESEARCH OF TECHNICAL EFFICIENCY OF CLOSED HORIZONTAL DRAINAGED

Abstract

The article presents generalized materials of long – term researches of technical efficiency of the closed horizontal drainage on the irrigated lands of the dry steppe zone of Ukraine. Horizontal drainage is a complex of hydraulic structures, which is a reliable system for preventing unwanted engineering – geological processes – flooding, secondary salinization and salinization of irrigated soils. Drainage provides the project ecological – reclamation condition of irrigated lands in most poorly drained and wasteless areas, where watershed plains and coastal lowlands are composed mainly of aeolian – deluvial loess with filtration coefficients of 0,25-0,50 m / day and depth. 0,0-20,0 from the ground surface are underlain by regional water resistance – red-brown clays with a filtration coefficient of 0,0001 m / day and less. Most of Ukraine’s irrigation systems are located in these natural and climatic conditions: Inguletskaya, Spasskaya, Yavkinskaya, Tatarbunarskaya, Danube-Dniester, Kakhovka, Krasnoznamyanskaya, North-Crimean and others, where irrigation systems and closed horizontal drainage have been built and operate for many decades. The soils on these systems are mainly dark chestnut and southern chernozems. The implementation of the Irrigation and Drainage Strategy in Ukraine for the period up to 2030 requires the restoration, reconstruction, technical modernization and further development of both irrigation and drainage systems, primarily closed horizontal drainage systems. This requires the generalization of all theoretical – methodological and practical experience in design, construction, operation and research aimed at improving the efficiency of closed horizontal drainage: technical, economic, environmental, reclamation. In the restoration of existing closed horizontal drainage systems, which was built in the 60s-80s of the last century and the construction of new drainage systems, the study of the technical condition and efficiency of drainage is a topical issue. On the basis of the materials of the conducted researches the integral, system methodological approach in researches of technical and reclamation efficiency of the closed horizontal drainage is developed, which includes: quantitative estimation of a technical condition of a collector – drainage network; use of regularities of formation of drainage runoff and drainage waters for control of ecological – reclamation condition of irrigated drained lands and efficiency of drainage functioning. It is offered to use the system of estimation of technical and ecological – reclamation efficiency of the closed horizontal drainage for the organization of monitoring of efficiency of functioning of each drainage site on all irrigation massifs.