Abstract
The article focuses on evaluating the efficiency of the vertical drainage system (VDS) in irrigated lands of the Maktaaral irrigation massif, located in the Turkestan region. The relevance of this study is related to the need for rational use of water and land resources amid growing water scarcity and the goals for increasing irrigated land area outlined in Kazakhstan's strategic documents. Mathematical modeling of the hydrogeological regime was carried out using the MODFLOW module within the GMS environment. The hydrogeological conditions were schematized, a hydrodynamic model was developed, the groundwater filtration regime was simulated, water balance calculations were performed, and predictive scenarios were analyzed. The modeling results revealed that the current VDS configuration fails to sufficiently lower groundwater levels in salinized areas, leading to secondary salinization and reduced crop yields. Based on the analysis, recommendations were proposed to optimize VDS parameters and operation, including increasing the number of wells and improving their placement. Implementing these measures will enhance the efficiency of melioration measures and create better conditions for sustainable agriculture in the region. The findings can also be applied to the development of similar systems in other irrigated areas with comparable conditions.