Comparison between the efficiencies of surface and pressurized irrigation systems in Jordan

A study was carried out to determine the efficiencies of water use in irrigation in the Jordan Valley Project. The study aimed to evaluate, the overall or project efficiency (E_p) which includes: the irrigation system efficiency, being the combined conveyance and distribution efficiency (E_s); and the field application efficiency (E_a). Evaluation of these efficiencies includes the comparison of open canals with surface irrigation versus pressurized pipes with sprinkler or drip irrigation systems. Data was collected from different sources to achieve the above mentioned purposes, beside the field experiments which were carried out specially for this study.It was found that the overall or project efficiency (E_p) for open surface canal with surface irrigation under citrus was 53%. While it was 42% under vegetables. Whereas E_p for pressurized pipe systems was 68%, and 70% for sprinkler and drip irrigation methods, respectively.The E_s for an open canal, (King Abdullah Canal, KAC) was 65%. While it was 77% for pressurized pipe projects during 1989–1991. Concerning the E_a, it was found to be equal to 82% and 64%, for surface irrigation on citrus and vegetables, respectively. Whereas it was 88% for citrus under sprinkler, and 91% for vegetables under drip irrigation. These values for the field application efficiency are acceptable according to Finkle (1982). The low E_s value for the canal is due, mainly, to high evaporation and seepage, unreported deliveries, and unavoidable measurement losses. Whereas, in pressurized pipe projects, it is due to the unreported deliveries, unavoidable measurement losses, and leakage.