The value of information for the management of water resources in agriculture: Assessing the economic viability of new methods to schedule irrigation

This study develops a methodology to assess the comparative advantages of new methods to plan irrigation with respect to prevailing existing irrigation practices. The methodology consists of a comparative cost-benefit analysis based on the Value of Information approach that makes it possible to analyse whether an improvement in the information available to farmers generates economic benefits. The method is applied to the problem of comparing computer irrigation models (providing irrigation advice based on measurements, water balance models and weather predictions) and prevailing irrigation practices (at times based on soil and plant observations, or on advanced technologies) in estimating and predicting crop water requirements, in pilot experiments located in four different European regions. The results reveal that the introduction of the alternative method improves the performance of irrigation practices in Mediterranean regions that are characterised by high weather variability and for those crops for which the consequences of failing to meet predictions are relatively low (i.e. tomato instead of maize, drip irrigated crops instead of sprinkler irrigated crops). Under favourable conditions, the use of the alternative technology generates a 0–20% increase in gross margin and a 10–30% water saving with respect to prevailing existing irrigation practices. The study concludes by addressing the conditions that justify the use of advanced information systems to schedule irrigation interventions and by offering some policy recommendations to drive their uptake. These include subsidising research at the evaluation stage and public investments aimed at knowledge creation (weather and shallow water table monitoring stations) and knowledge sharing (counselling) at the adoption stage.