A multicriteria assessment method to compare scenarios of water management in agricultural landscapes

In the Aveyron watershed (South-Western France), where the agricultural economy mainlyrelies on irrigated productions (maize and fruits), engaging changes in quantitative water managementis socially challenging. The watershed suffers from a structural misbalance between the water demandand the water offer, and recurring crises in the low-flow period lead to emergency restrictions of use.This situation tenses competing stakeholder positions and erodes the social-ecological system’sresilience.Characterizing and valuing options for change can support decision-making. Nonetheless,the various expert assessments that flourished as answers to political incentives for a bettermanagement of watershed did not succeed in bringing out socially-accepted solutions. Wehypothesize that expert judgments (alone) cannot frame problems that also arise from colliding valuesand interests. Hence we built a spatialized multi-actor multi-criteria assessment method in order tomap out matches and mismatches between the people involved and between the stakes relevant tothem.This method proceeds through various steps: 1) Problem structuring: relevant stakeholders areidentified; criteria and scenarios are defined following a bottom-up approach; 2) Definition andevaluation of a set of indicators for each scenario, using mainly model simulations of watermanagement; 3) Mapping out stakeholder judgments; 4) Collective deliberation over the sociallyrelevantoption(s) for change. A specificity of the method lies in the way stakeholder judgments areelicited and represented (step 3). Indicators constitute arguments that stakeholders can combine toexpress their judgments. Stakeholders map out where one scenario is acceptable to them and whereit is not (spatialized judgments). In addition, they can define places of special importance for eachcriterion (spatialized weights). Integrating those maps would help change the focus from “whichscenario is the best” to “where does a scenario bring out conflicts and where is it consensual option”.We expect such a transformation to favour social learning and the design of new technical andorganizational solutions for watershed management.