Heavy metal removal in a detention basin for road runoff

Abstract

Road runoff produced during rainfalls has significant pollutant load, which can cause important environmental impacts on waste and soil. The efficiency of a detention basin for removing heavy metals (Cr, Cu and Zn) in road runoff was evaluated for 8 rainfalls over one year with different intensities (between 16 mm and 103 mm) and durations (higher than 3 hours). The basin showed good performance for removing all metals for precipitation intensities between 16 mm and 103 mm and rainfall durations up to 3 hours. The volume of the basin is suitable for retaining all the road runoff coming from rainfalls with intensities lower than 29.4 mm and duration longer than 6 hours. This type of monitoring should be introduced in Environmental Monitoring Plans of roads because it allows evaluating the effectiveness of treatment systems and preventing the possible impacts of discharges into the environment.