Evaluation of the Hydraulic Design of Culverts Under a Climate Change Scenario: A Preliminary Analysis of Road Case Studies in Southern Portugal

The present work aims to contribute to the study of current capacity of culverts associated to transportation infrastructures, under a climate change scenario. The records of annual maximum daily precipitation were analysed for two meteorological stations, allowing to estimate such precipitation for both stations, namely through the adjustment of a statistical law for a return period of 100 years. Design precipitations were then determined through a methodology that makes use of annual maximum daily precipitation estimation. Through hydrological and hydraulic methodologies frequently used in hydraulic and drainage projects in Portugal, eight culverts were evaluated. The hydraulic analysis led to the conclusion that three out of eight culverts had an insufficient flow rate capacity. According to those results, it is not possible to conclude that climate change is directly influencing the adequacy of such culverts, in terms of flow rate capacity. Nevertheless, it seems reasonable to expect that a considerable number of culverts may no longer be suitable in terms of flow rate capacity, resulting in a potential high number of critical points in the Portuguese road network, jeopardizing the safety of the transportation infrastructure and its users.