Wastewater treatment in Brazil: Institutional framework, recent initiatives and actual plant performance

Brazil, like many other developing countries, suffers from widespread pollution of the aquatic environment caused by the uncontrolled discharge of untreated urban wastewater. Some states have made greater progress towards the implementation of pollution mitigation strategies than others. However, a study undertaken in the states of So Paulo and Minas Gerais indicates that installation of treatment plants is not sufficient to meet effluent quality objectives. A range of different wastewater treatment processes were investigated and, although conclusive results were difficult to define due to the large differences in the frequency of sampling, the results showed a highly variable performance, in which many processes were not operating satisfactorily according to expected design performance or environmental standards set by the regulatory authority. In light of these findings, the paper discusses an innovative programme called PRODES, introduced by the National Water Agency (ANA), which aims to encourage public and private companies to implement new treatment plants and to improve the performance of existing wastewater treatment systems based upon a system of financial incentives according to the monitored reduction in pollutant loads. The paper concludes that this approach has considerable potential as part of a pollution mitigation strategy, but success is dependent on the development of a standardized framework for routine performance evaluation and monitoring to improve operational performance and regulatory procedures.