EVALUATE THE PERFORMANCE OF SMALLHOLDER IRRIGATION SCHEMES IN TANZANIA

Abstract

Concerning agricultural production and food supply, irrigation is of significant importance in many countries. A big problem in the irrigation scheme has been the safe and successful use of irrigation water. Irrigation management aims to preserve water within the root zone where crop yield and quality are not affected by insufficient or excess humidity. The depth of water application can be greater than or less than the optimal water depth needed for a given crop according to conventional surface irrigation practices. The profit and risk evaluation of irrigation water became crucial in identifying the location of the problem and identifying more effective alternatives. Therefore, this research aims to evaluate smallholder irrigation's performance in Iringa District Council and suggest potential improvements based on the sustainable modernization of irrigation schemes and reduce the irrigation schemes' evaluation output gap. The analysis will help identify the scheme's management's existing deficiencies, affecting the entire system's efficiency. The irrigation schemes' performance assessment in Luganga, Magozi, and Mkombozi evaluated internal and external indicators. Using comparative performance indicators, the external performance appraisal was conducted. On the other hand, the internal performance evaluation was carried out to understand the influence of institutional frameworks on the irrigation system's efficiency at the given level of external performance; Fuzzy set principles were used. The system's administrative structure of all three irrigation schemes has eight organs responsible for the program's administration. The bodies are the general assembly, the IO committee, the IO committee (Central committee), Auditors, O&M sub-committee, Planning & Finance sub-committee, Agriculture & environmental sub-committee, Block leaders, IO members. Average utility values were compared across the schemes to get an accurate picture of the critical variables' overall success, i.e., Water Flexibility, Adequate irrigation water, and Irrigation water expectation. The average water flexibility utility values were between 0.54 and 0.90. The average of adequate irrigation water utility values at the three irrigation schemes lies between 0.55 and 0.90. At the same time, the average Irrigation Water Expectation lies between 0.46 to 0.85. The average utility indicated the irrigation water supplied more at the head and middle of irrigation areas than at the end stream of irrigation areas. There is a need to prepare of irrigation scheduled which will consider all parties of irrigation schemes. The comparative performance indicators used for the evaluation were divided into four categories in the current study: water supply, agricultural, economic, and physical indicators. Compared to other methods, the result provided by Mkombozi has the smallest ratios for both Relative Water Supply (RWS) and Relative Irrigation Supply (RIS). At Mkombozi, the value of RWS was between 0.7 to 1.6, while the value of RIS was between 0.19 to 1.09. In both cases, the Luganga irrigation scheme has higher values, i.e., RWS and RIS. RWS values range from 1.25 to 2.63, and RIS values range from 0.82 to 2.20. Simultaneously, the outcome reveals that both systems had higher RWS and RIS in the head and middle reaches, while in both schemes, the tail reach had lower RWS and RIS.