Comparative Multi-Criteria Assessment of Hydrological Vulnerability—Case Study: Drainage Basins in the Northeast Region of Romania

Abstract

Hydrological vulnerability (HV) is a (changing) underlying condition in all drainage basins, depending on the dynamics of the potentially dangerous hydrological phenomena, the particularities of drainage networks, land use patterns, and processes that shape landforms in extensive periods. The socioeconomic attributes and the hydrotechnical infrastructure add up to the manifestation of this type of vulnerability. In this paper, we assess the HV levels of 81 drainage basins in the NE of Romania for three distinctive periods (1990–1999, 2000–2009, 2010–2018), using a multi-criteria approach. Two classical multi-criteria decision making (MCDM) methods were combined in order to evaluate the HV according to factors that refer to floods and hydrological drought occurrences, hydrotechnical structure coverage, the drainage network, land use, and landforms characteristics. The Analytic Hierarchy Process (AHP) was applied to weigh these factors and the resulting relative importance values were integrated in the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), by which the alternatives represented by the catchments were ranked. The attenuation of the HV through time follows an East–West direction, from the lower elevations of the Moldavian Plateau to the heights of the Carpathians. Hydrological droughts are more likely to occur in the Eastern part of the analyzed territory, while the western section displays a certain propensity for floods. The results may be used by local and national authorities in order to improve the hydrological risk mitigation strategies, and to develop more targeted water management projects, properly calibrated to the conditions of the Northeast Development Region in Romania.