Avaliação do impacto de medidas não convencionais de microdrenagem urbana aplicadas a um loteamento

Abstract

The strong urban growth unfolded in recent decades, often achieved by without proper planning, impacts natural conditions of watersheds drainage, since it enlarges impermeable areas and surface runoff volume and speed. Traditional urban drainage techniques, represented by tunnels, sewers and other structures given that exceeding flow is transferred to downstream areas, are not enough to settle such problem. Therefore, other alternative techniques of urban drainage became widespread, which prioritize expanding permeable areas or dampen tributary flows. This study aims to simulate and implement alternative techniques of urban micro-drainage in an allotment located in Ceará-Mirim, RN, Brazil, comparing the total volume discharged with and without such techniques. In order to conduct the simulations, design and modeling software related to the drainage field were used. In total, following six simulation scenarios were considered: approximately 100% waterproof area; 20% permeable area; 40% permeable area; area with cisterns; area with infiltration trenches and approximately 100% permeable area. The scenario used for simulating cisterns emerging as the most efficient one compared to the others, promoted a reduction of surface runoff of approximately 30%. In conclusion, structural compensatory techniques related to urban drainage allowed considerable reduction in surface runoff with the advantage of some of them enabling recharge of the local aquifer.