A combined GIS-MCDA approach to prioritize stream water quality interventions, based on the contamination risk and intervention complexity

Water management decisions are complex ever since they dependent on adopted politics, social objectives, environmental impacts, and economic determinants. To adequately address hydric resources issues, it is crucial to rely scientific data models guiding decision-makers. The present study brings a new methodology, consisting of combined GIS-MCDA, prioritize catchments that require interventions improve surface water quality. A Portuguese catchment, Ave River Basin, was selected test this methodology due the low First, calculated contamination risk each based GIS-MCDA using point source pressures, landscape metrics, diffuse emissions as criteria. This analysis compared local ecological chemical status through ANOVA Tukey test. results showed efficiency method lower for under good higher in with classification. In second task, intervention complexity different GIS-MCDA. For approach, chosen five criteria condition interventions, population density, slope, percentage burned areas, Strahler order, number effluent discharge sites. Both multicriteria methods were graphical rank priority, subdividing prioritization into four categories from 1st 4th, giving preference high complexity. As result, dominantly placed classified 2nd. total, 248 spatially ranked, which an essential finding decision-makers, willing safeguard catchment