Implementation of parcels of land micro-reservoirs as a strategy to reduce water volume in galleries and peak flows in the micro-drainage system of a new subdivision

Urbanization has caused significant environmental impacts on natural cycles, particularly the hydrological cycle. Soil impermeabilization increases surface runoff, contributing to the higher frequency and intensity of urban flooding. This phenomenon underscores the growing vulnerability of cities to extreme events, which are further exacerbated by climate change. Precipitation patterns have been shifting due to climate alterations, necessitating adaptations to IDF curves, which are critical for planning climate adaptation strategies. In many cases, existing drainage systems are insufficient to handle the impacts of urbanization and intense rainfall events. In this context, the adoption of techniques that control flow distribution over time and mitigate peak flows may be crucial for flood control, especially in urbanized areas. Green infrastructure techniques, such as Low Impact Development (LID) practices, have proven effective in mitigating urban flooding. Among these measures, infiltration techniques such as green roofs and permeable pavements, as well as storage techniques such as retention basins, detention basins and rain barrels (RB), stand out. This study examines the impact of implementing RB in the microdrainage system of a new subdivision in the interior of Paraná. The simulations were conducted for return time of 1, 5, and 10 years, indicating potential failures in the drainage system. To prevent flooding, the strategic inclusion of RB was proposed to mitigate peak flows in the drainage galleries, preventing overflow and system overload, and reducing peak flow by up to 47%.