Water users associations and irrigation water use efficiency in costal oases areas of Gabes, South-eastern Tunisia

The objective of this study was to measure the efficiency level Water Users Associations (WUAs) in coastal oases Gabès (South-Est Tunisia) and assessing its main determinants. First, an input-oriented data envelopment analysis (DEA) used relative scores WUAs evaluate management maintenance costs sub-vectors efficiencies separately through a mathematical modification initial DEA specification. In second stage, critical determinants sub-vector are determined by applying Tobit model. A key finding is that clearly inefficient. Results show on average, 38% inputs could be saved if operated frontier. inefficiency found can mainly attributed number water pumping stations managed, ratio losses WUAs' age. results also discrepancy between technical values calculated under CRS VRS assumptions, resulting 20% scale inefficiency. revealed more linked with engineering inefficiencies than their inefficiencies.