DEVELOPMENT OF AN INDEX FOR PERFORMANCE EVALUATION OF URBAN DRAINAGE SYSTEMS IN SMALL MUNICIPALITIES

Resumo

Urbanization intensifies extreme events and increases population vulnerability, especially in small municipalities, where the lack of planning, limited resources, and the absence or inefficiency of urban drainage systems exacerbate the impacts. Thus, evaluating and monitoring the performance of these services is essential for identifying critical areas. This study developed a performance index for stormwater drainage adapted to the limitations of municipalities in Paraíba, incorporating indicators related to infrastructure, maintenance, urbanization, health, risk management, and legislation. The methodology comprised five steps: characterization of the study area, selection of indicators, definition of nominal classification, application of the Analytic Hierarchy Process method, and application of the Stormwater Drainage and Management Service Performance Index (IDDAP-PB). The municipalities of Areia, Cabaceiras, Natuba, Nova Olinda, São Bento, São José de Piranhas, São José dos Ramos, and Serra Grande were selected as case studies. Consultation with specialists indicated greater importance attributed to the indicators of risk management, existing systems, and urbanization. The results revealed precarious infrastructure and weak risk management policies as the main challenges faced by the municipalities of Paraíba. The index proved to be robust in assessing drainage system performance and consistent with local conditions, but it was considered sensitive when comparing municipalities. Among the municipalities analyzed, Serra Grande showed the best performance, while Natuba had the poorest result. The IDDAP-PB can guide public policies and investments, reducing vulnerabilities and supporting informed decision-making. The methodology is replicable but depends on data quality and periodicity to ensure its effectiveness.