Private ownership of water and wastewater systems: Assessing health impacts

Abstract

This study examines the impact of private ownership of water and wastewater systems on disease reduction linked to sanitation in Brazil from 1998 to 2021. It updates Saiani and de Azevedo (2018), which analyzed the period 1995–2008, by incorporating over a decade of additional data, key policy changes such as the 2020 Sanitation Law, and employing the Callaway–Sant’Anna Staggered DID methodology to address heterogeneity in treatment effects. Our findings reveal mixed results: while some municipalities achieved reductions in morbidity rates, others showed no change or increases, underscoring the context-dependent nature of privatization outcomes. A notable example is the case of Tocantins, where transitioning from a hybrid private-state model to full private ownership led to a significant decrease in disease morbidity, particularly among the most affected age groups. These advancements provide a robust, updated perspective on the privatization debate, offering valuable implications for policy and practice.