In several arid and semi-arid Mediterranean basins, water deficits in irrigated agriculture during drought events are relieved by illegal abstractions from aquifers. Illegal abstractions are largely tolerated by the authorities and are regarded by farmers as a reliable and inexpensive form of...

For an irrigator, investments in on-farm water infrastructure that increase the marginal productivity of water may improve use efficiency. However, increasing on-farm water use efficiency invariably diminishes return flows, compromising the ability to maintain sufficient water flows in streams...