灌溉排水系统工程

Performance Evaluation of Furrow Irrigation Hydraulics Using WinSRFR Model: The Case of Batu Degaga Small Scale Irrigation Scheme

Abstract

Chari Abelti*

Furrow irrigation is the dominant surface irrigation method applied worldwide. However, the performance of furrow irrigation is low. Advanced simulation models of surface irrigation have been proved to be effective for the evaluation of system design and management. Batu degaga irrigation scheme is one of the small-scale irrigation schemes in ethiopia. Therefore, this study aimed to evaluate the hydraulic performance of furrow irrigation at batu degaga small scale irrigation scheme using the WinSRFR model. A field experiment was conducted and all measurements used for input parameters were collected from the field. The collected data were processed by Microsoft EXCEL and data analysis was conducted using WinSRFR 4.1.3 software. The statistical indicators of NRMSE, R², RE, d, and λ were used for the comparison between measured and simulated advance time, and recession time. The results of these indicators were 10.5%, 0.98, 0.97, 0.97, and 0.98 for advance time; 2.86%, 0.99, 0.99, 0.9, and 0.995 for recession time which was very good and showed that WinSRFR simulation was acceptable.

Hence, WinSRFR software was employed to evaluate the performance of basic indicators of furrow irrigation such as application efficiency, distribution uniformity, and deep percolation. The study revealed that the average application efficiency, deep percolation, and distribution uniformity were 58.2%, 41.8%, and 89% under 1ls^-1 inflow rate respectively, and 54.3%, 45.7%, and 91% under 1.5 ls^-1 inflow rate respectively for 100 m furrow length with 0.2% bed slope. This indicates the hydraulic performance of the furrow irrigation system of the study area was poor, even though the greater performance was attained under 1ls^-1 inflow rate compared to 1.5 ls^-1 inflow rate, Finally, the optimum combination of furrow hydraulic parameters should be identified and suggested for effective management and use of irrigation water to improve performance of furrow irrigation of the study area.