Improvement of water quality in urban rivers: new paradigms to explore – Pinheiros river basin, São Paulo, Brazil

Abstract

The issue of water quality in urban water bodies is complicated, as it involves controlling on point and diffuse pollution loads. Point loads are still a problem in Brazil, although more easily identifiable. Diffuse loads do not have a specific discharge point, which makes their control more difficult, and they happen mainly due to stormwater surface runoff. Urban water bodies are exposed to the diffuse pollution, which affects their water quality and multiple uses. Thus, this article presents the Pinheiros River's water quality monitoring over the last ten years, analyzes the monitoring results of São Paulo State Environmental Company (Cetesb), and verifies the existence of a relationship with these results with the daily monitoring of the project “Avaliação da Qualidade das Águas do Sistema Pinheiros-Billings com o Protótipo Flotação”. Finally, it evaluates the use of a bioretention system with average reductions of runoff pollutants loads, in some cases, more than 90%, being an alternative for diffuse pollution control in the Pinheiros River basin.

Keywords:
diffuse pollution; urban area; bioretention