Modern aspects of scientific support for the restoration of drainage systems in the humid zone of Ukraine

Modern aspects of scientific support for the restoration (reconstruction and modernization) of drainage systems in the humid zone of Ukraine were determined, which were established based on the results of the analysis of the current state and features of drainage systems functioning. One of the priority areas is the development of a scientific justification of improving water supply for drainage systems. The most effective and economical technological method of increasing the water supply in reclaimed areas is the accumulation of local drainage runoff. Given the shortage of local drainage and surface runoff, increasing the water supply in reclaimed areas is provided by withdrawing and supplying to reclamation systems extra water volumes from existing reservoirs, rivers, ponds, lakes, located both within and beyond the systems. The current structure of agricultural use of drained lands in the humid zone is subject to both climate change and export market conditions. In agricultural production such crops as grain corn, sunflower, rapeseed, soybeans are cultivated. Changes in the use of drained land should be taken into account when justifying the reconstruction or modernization of drainage systems. This will enable to develop and implement a set of measures for technical re-equipment and reconstruction of drainage systems, introduce advanced resource-saving technology for growing economically attractive crops and ensure effective water regulation on drained land sin accordance with the requirements of agricultural production. The technical state of modern drainage systems in the humid zone is mainly characterized by two conditions: satisfactory, when the systems are under operation (operational) and can perform their functions keeping the design mode, and unsatisfactory, when the restoration of drainage systems is only possible provided modernization measures. Given climate change, the priority measures for the modernization of drainage systems should include work to expand their functionality to regulate soil water regime throughout the growing season. In view of the cost of modernization to expand the functionality of different types of systems (drainage, drainage and irrigation, polder and water circulation) by constructing irrigation systems on them is much lower compared to modernize them to drainage and irrigation ones when  using sluice technology, preference should be given namely to the construction of irrigation systems.