Evaluation of subsurface drainage performance in Lithuania

In Lithuania, knowledge of subsurface drainage performance is important in order to use reclaimed land rationally and to apply the scarce available financial means to repair improperly functioning drains. Subsurface drainage is also instrumental in the improvement of non-productive soils and it can assist in avoiding unsuitable soil conditions during farming operations. The experimental site, situated at Pikeliai in the K≐dainiai district of central-Lithuania, consists of seven plots with various combinations of drainage materials. To evaluate drainage performance, discharges and water heads on top of and midway between drains were measured during four consecutive seasons. Low rainfall during the second and third seasons resulted in small discharges and low groundwater tables compared to the first and fourth seasons.