Usually, deposition in drip irrigation is not done during irrigation in the equipment, but also occurs Iranian Pistachio when the irrigation is stopped and the water stays in the pipes and equipment until the next period. Of course, this operation (filling the system with suitable water in terms of quality) may be enough for two or three irrigations, but if fresh water is not available, acid injection can be used in the last hours of irrigation to wash the pipes and In the last two hours, only acid-free water was sent into the system. This water will not have much tendency to precipitate due to the acid washing of the pipe walls. If the soil is saline or the soil texture is heavy and if it is not possible to wash with flood irrigation in winter, if we want to use low quality water, it is better to use the drip irrigation method. In this method, due to the lack of evaporation, the accumulation of salts and their increase in the surface is prevented, and if properly irrigated, soil salinity will not be more than water salinity.