The article describes the construction technology of closed horizontal drainage in irrigated areas, presents the results of theoretical studies to determine the depth of drainage, the width of the drainage trench, the diameter of the drainage pipe, the thickness of the filter material, the distance between the drains and the drainage module. According to the results of theoretical studies, the average drainage depth is 1.5 m, the width of the drainage trench is 0.3 m, the diameter of the drainage pipe is 0.1 m, the thickness of the filtration material is 0.1 m. The distance between the drains is 150 m with the drainage module 0.1 l/s, the distance between drains is 180 m with a drain module of 0.12 l/s, and the distance between drains is 210 m with a drain module of 0.14 l/s.