Using In-Line Storage Strategy to Improve the Operation of Automatic Main Irrigation Canals (Case Study: Dez Main Irrigation Canal)

Successful operation of a main irrigation canal system is achieved under the conditions that
differences between supply and demands are eliminated. In this research, the effect of In-Line storage
strategy on operation and management of an automatic main irrigation canal is assessed as an
approachable method for improving the main irrigation canal performance in rehabilitation and
modernization projects. A Proportional-Integral (PI) local upstream controller is designed for Dez
main irrigation canal to assess the capability of the proposed strategy. The controller was tested for an
extreme and sudden increasing–decreasing water off-taking scenario on two different operation
conditions. The first one refers to the normal operation and the latter refers to operation of the main
canal with in-line storage in the three canal reaches of the case under study. Controller performance
was evaluated with ASCE indices includes: MAE; IAE; and StE, for irrigation schedule time period
(6 days). Results indicate that using in-line storage strategy leads operational performance
improvement. The maximum MAE index improvement happens in the first canal reach with
improving values from 2.1 to 0.32. For the IAE and StE indices, maximum improvements are
obtained from 1.3 to 0.5; and from 0.71 to 0.14 respectively. The satisfactory results is obtained for
the irrigation schedule with drastic changes, so using in-line reservoirs lead to the better results for the
normal irrigation schedule.