The aim of this study is to conduct an ex post analysis of the generalized implementation of drip irrigation in the last two decades in the Valencia Region (Spain). Due to the important role played by water users' associations (WUAs) in this socio-technological change in the region, this research was based on 77 interviews with different WUAs that provided information prior and subsequent to modernization. Firstly, we review the published studies concerning the effects generated by this technological change and describe the drip irrigation promotion policies implemented by national and regional governments. Subsequently, we analyse the consequences for irrigation associations, including effects on water use and irrigation costs. The reduction of water withdrawals has been generally significant. This was possible because the regional contextual factors prevented, in most cases, crop intensification and areal expansion. Nevertheless, due to the enormous investment effort and the resulting maintenance costs, the technological change has increased irrigation costs, generating some uncertainties concerning the financial sustainability of some WUAs. In conclusion, a thorough assessment of contextual factors and accompanying measures such as technical assistance and monitoring appear to be indispensable to avoid unforeseen effects and to achieve the potential goals of conversion to drip technologies.

Agricultural irrigation is the major water consumer in the Mediterranean region. In response to the growing pressure on freshwater resources, more efficient irrigation technologies have been widely promoted. In this study, we assess the impact of the ongoing transition from flood to drip irrigation on future hydroclimatic regimes under various climate change scenarios, with a particular focus on actual evapotranspiration and groundwater recharge in the Mediterranean region of Valencia, Spain. Hydroclimatic predictions for the near‐term future (2020–2049) and the mid‐term future (2045–2074) were made under two emission scenarios (RCP 4.5 and RCP 8.5) using a hydrological model that was forced with data from five GCM‐RCM combinations and field‐based irrigation volume and frequency observations. Our findings suggest that climate change could lead to statistically significant changes in the regional hydroclimatic regime despite projection uncertainties. Major changes include a statistically significant decrease in mean groundwater recharge of up to −6.6% under flood irrigation and −9.3% under drip irrigation and contrasting changes in mean actual evapotranspiration for flood and drip irrigation in the order of +1% and −2.1%, respectively. Since sustainably available water resources in the Valencia region are entirely allocated, the expected changes and associated uncertainties create a challenging context for future water management. Our simulations further indicate that, rather than climate change, the choice of irrigation technique may have a greater impact on actual evapotranspiration and groundwater recharge. Our findings therefore highlight the importance of considering both climate change and irrigation technique when assessing future water resources in irrigated Mediterranean agriculture.