Effectiveness of Emitter Flushing used for Subsurface Drip Irrigation System

Abstract

Filtration plays vital role to improve the efficacy and reduce the maintenance of drip irrigation systems. The experiment was conducted to evaluate drip irrigation filters (gravel, disk filter and their combination) for groundwater filtration. Water quality parameters responsible for emitter plugging, such as total solids, turbidity, Ca, Mg, CO and HCO were 3 3 analyzed at the entry and exit points of filters. The filtration efficiency for water quality parameters was estimated with individual filters and in combination. Significant improvement was observed for turbidity, total solids, carbonate and bicarbonate. The filtration efficiency with combination filter was 14.3±8.8% for turbidity and 16.3±9.31% for bicarbonates. Gravel filter gave better results for filtration of bicarbonate in comparison to the disk filter. Emitters protected by the gravel media filter experienced the largest flow rate reductions but emitters protected by combination filters experienced least flow rate reduction. Backwashing of filters reduces the filtration efficiency and head loss. To reduce emitter plugging by removal of accumulated sediment, flushing of mains, submains and laterals are recommended. Higher improvement in uniformity coefficient was observed in subsurface drip after flushing operation. The results may be utilized in planning and design of subsurface drip irrigation system to diminish emitter clogging incidence.