Irrigation Performance of a Water Distribution System: The Case of Kigugu Irrigation Scheme-Mvomero District Morogoro Region-Tanzania

This study assessed the performance of the Kigugu Irrigation Scheme's water distribution system in Tanzania with an emphasis on its impact on crop yields. We used a combination of participatory tools and direct observation to gather comprehensive data, including weather patterns, water discharge rates, and farmer input levels. Descriptive statistical analysis revealed significant variations in water distribution across canals, with Relative Water Supply (RWS) values ranging from 0.7 to 5.9, indicating instances of both over- and under-supply. Despite these variations, satisfactory performance was demonstrated by the irrigation system, with high Water Delivery Performance Ratio (WDPR) values consistently recorded above 0.65, indicating that water demands were largely met across the system. Furthermore, the study found that equity in water distribution improved significantly during the growing season, with the equity index dropping from 0.2 to 0.1. This underscores the critical need for fair water allocation practices, particularly during low-flow periods, to ensure that all farmers receive an adequate supply. Based on these findings, several recommendations for irrigation system modifications were proposed to further improve water distribution and equity. In terms of productivity, a notable correlation between water distribution and crop yield was observed. A canal with a design discharge of 0.0228 m<sup>2</sup>/s produced a yield of 552.18 metric tonnes, demonstrating efficient water utilization. In contrast, canal SC.4-2, with a lower discharge of 0.0185 m2/s, achieved a smaller yield of 274.31 metric tonnes, further highlighting the importance of optimal water distribution for enhancing agricultural productivity. Overall, the Kigugu Irrigation Scheme maintains a reliable water supply, contributing positively to sustainable water resource management and agricultural productivity. This, in turn, supports local economic growth, enhances food security, and improves community well-being. The study’s findings provide critical insights for future improvements in irrigation management and resource allocation.