Qualitative and quantitative control of the urban runoff with detention basis

Abstract

Floods in urban areas are responsible for impacts that go from puddles formation to environmental and social disasters. Looking for alternatives to minimize the effects of floods in urban areas, some methodologies have been studied and applied, such as the use of detention basin in high consolidated urban areas. This study analyses the efficiency on flood control of two detention basins, a dry and a wet one. The study approaches both quantitative and qualitative aspects related to runoff from an urban area of Brasilia city, federal district of Brazil. The affluent caught by the detention basins is related to a conventional urban drainage system with a 4.75km2 (dry basin) and 6.12km2 (wet basin) contribution area. The results showed that the basins can reduce the peak income flow significantly (averaged 62.6% and 74% peak flow reduction, for dry and wet basin, respectively) and has positive impact over pollution control, with an average reduction of 1 to 3% for BOD and up to 41 to 74% for Suspended Solids.