Proposta de metodologia para orientação de processos decisórios relativos a intervenções em cursos de água em áreas urbanas

Abstract

Interventions in urban rivers have been under much discussion. The tendency of adopting more integrated approaches combined with traditional engineering techniques is increasing and inserting new elements in the processes of analysis and decision multiple disciplines, scopes and agents making the selection of alternatives even more difficult. Due to the lack of methodologies focused on helping the decision process mentioned, this work proposes a tool with this aim, incorporating fluvial and environmental variables to those related to the urban scenario. Therefore, the proposed systematic consists of structuring the phases of a multicriterial decision process related to urban interventions that may affect, in different levels, rivers and creeks. It aims at helping the preliminary phase of studies, taking into account the interventions objectives, the diagnosis of the fluvial and urban environments, the conception of alternatives, their feasibility analyses and their performance, impact, costs and level of objectives attendance analysis, making it possible to compare them all in global terms. In general terms, the process is based on qualitative analyses, incorporating, whenever possible, quantitative aspects which demands outstanding criterion and judgment by the analyst. On the other hand, the methodology is simple and easy to apply, besides being significantly flexible, allowing the incorporation of new elements of analysis or the elimination of the ones not considered pertinent. The establishment of different weights to the intervention objectives and to the performance/impact indicators prioritizing them according to the particularities of each area makes it possible to apply the systematic to the most various scenarios. The combination of these criteria with the implementation and maintenance costs of the alternatives, formalized by quantitative treatment what minimizes the analysis subjectivity constitutes the orientating basis of the decision process. The proposed systematic was applied to a case study in the city of Belo Horizonte, Brazil, and demonstrated its consistency and potential to help decision processes related to interventions in water courses, considering the preliminary phase of alternatives conception and analysis.