Doroodzan and Zayandeh-rood Irrigation Network Operation and Maintenance System

History reveals that waterworks began thousands of years ago in ancient Iran. The main objective in operation and maintenance of an irrigation network is to increase the efficiency of the system. In this study, the performance of regulating structures of Doroodzan Irrigation Network (mainly slide and radial gates)were compared with those of Neyrpic module orifices, in Zayandeh-rood Irrigation Network. The comparison was based on perfomance and operation of each system. Based on the results obtained, the following recommendations are made: Performance of the structures becomes poorer with time due to the operation and maintenance of both systems. Department of Agriculture should be more involved in the management of the irrigation networks. Land consolidation is a key parameter in better performance of the systems. Government should stop subsidizing the water tariff for the farmers. Instead, the budget should be allocated for operation and maintenance purposes. This will help minimizing the water losses of the systems. Establishment of the independent irrigation and drainage cooperations run by the farmers. With an overall project efficiency of around 46%, about 20% of the total delivered water was distributed unreliably. Water distribution equity along tertiaries was also found to be poor. A contributing factor could be the poor operation and maintenance of gates.