Evaluation of Drip Irrigation in the Province of Mazandaran of Northern Iran a Case Study on the City of Babol

In this research, ten orchards in various parts of the city of Babol with different soil and water conditions were chosen as the sample and were studied with the purpose of evaluating and investigating the problems facing drip irrigation systems. In all of these ten orchards, emitter discharges were considerably lower than the expected rates due to low water pressure and blockage of emitters. Therefore, orchard owners increase the duration of irrigation and sometimes even apply more than twice the quantity of water needed by each tree. Blockage of emitters is one of the most important problems confronted by orchard owners. We tested the four - liter - per hour emitters, which are the most common emitters used in this region. The coefficient of variation and the emission uniformity of the fifty new emitters we tested in our study were claimed by the manufacturing company to be 7.1 and 91 percent, respectively. The range of the coefficient of emission uniformity varied from 0.68 to 0.91, the potential application efficiency of lower quarter from 0.61 to 0.82, and the actual application efficiency of lower quarter from 0.51 to 0.85. If the problem of emitter blockage is solved, we can use fewer emitters or reduce the duration of irrigation and, thereby, save on energy consumption. The average emitter discharge in the orchards studied was less than the desired level due to the quality of the irrigaton water and the low pressure in the irrigation systems. Turbine pumps can be used to raise the water pressure of systems faced with low water pressure to the desirable level. In orchards where there is a considerable difference between the desired and actual water pressures, pressure-regulating valves need to be installed in required places to create more uniformity.