Author(s): Thiago M. Osawa; Jose R. S. Martins
Linked Author(s): Jose Rodolfo Scarati Martins
Keywords: First Flush; Rainwater Harvesting; Roof Runoff; Stormwater Management; Sizing Criteria
Abstract: This study presents the application of a novel methodology for identifying and quantifying the first flush (FF) phenomenon in runoff generated by a ceramic tiled roof. The method, which addresses the limitations of traditional FF approaches, was tested on runoff samples collected during 24 rainfall events. The analysis was based on Total Organic Carbon (TOC) and Electrical Conductivity (EC) concentrations, with slices of 1,3, and 5 mm used to group data via non-parametric statistical tests. The results indicated the presence of the FF for both parameters, with the first flush volume ranging between 25 and 27 mm. This volume, higher than reported in previous studies, emphasizes the influence of site-specific conditions. The novel approach demonstrates potential advantages for accurately sizing rainwater harvesting treatment systems, offering a robust tool for sustainable stormwater management. Future research should focus on comparing these findings with water quality standards and legislation to ensure safe reuse of harvested rainwater.
Year: 2024