Avaliação do desempenho de dois poços de infiltração com características distintas como medida de contenção de drenagem urbana na fonte

Abstract

The advancement of the urban perimeter brings challenges for technicians and managers so that the new scenario has characteristics closer to the natural, ensuring that rainwater does not cause environmental, social and economic damages. In this context, this work sought to evaluate the compensatory technique of drainage infiltration at the source, implanting two soakaway pits, with distinct characteristics, both with an usable volume of 5.78 m³, in an area of an upcoming residential land division, in the municipality of Caxias do Sul, RS. Pit 1 was composed of preformed and perforated reinforced concrete walls and Pit 2 was excavated and filled with gravel graduated. The systems were tested and monitored through flow simulations, demonstrating that they had capacity above the one stipulated in the project, being Pit 1 capable of containing a volume 2.9 times greater than dimensioned and Pit 2 a volume 1.5 greater than the one projected. Pit 2 showed lower emptying efficiency than Pit 1 when subjected to similar volumes, taking 3 h 48 min to empty to 32 cm water level, while Pit 1 completely emptied in 50 min. Also, the costs of implementing the systems were evaluated, with Pit 2 being 40.8 % more economical than Pit 1. Finally, it was concluded that soakaway pits are good alternatives for the control and prevention of urban floods, for sites with characteristics similar to those of the evaluated one.