Tapping into Health: Drinking Water Quality and Early Childhood Development

• In Event: Institutions and Information in Environmental Public Goods Provision

Abstract

Safe drinking water is critical for child health and development, yet billions lack access to safely managed drinking water globally. Policies and programs aimed at improving drinking water quality have focused both on improving point source water quality through municipal water treatment as well as motivating the use of filtration, boiling, and other methods for point of use improvements. Against a backdrop of approximately half the population lacking access to safe drinking water, between 2019-2022 the national government of Peru implemented a nationwide chlorination program that increased chlorination in water systems and improved system management. Specifically, it delivered three water quality improvements: (i) installation of drip chlorination systems; (ii) distribution of chlorine supplies for disinfecting drinking water; and (iii) building local capacity for safe water system management.

In this paper, we investigate the impacts of improved drinking water quality in early childhood by evaluating the health effects of Peru’s water chlorination program. We combine policy rollout data with repeated cross-sectional household survey data for the period of 2015–2023. We use difference-in-differences and event study analyses to examine policy impacts in the aggregate as well as over time. Several results emerge. First, among children exposed to the program, height-for-age z-scores increased by 0.04 and 0.05 (a 4 to 5 percent increase from the baseline mean). Event study estimates show that height improvements are largest in the three to four years following the program, suggesting that cumulative exposure to improved drinking water and exposure at earlier ages may explain these benefits to height. Second, effects on health are larger and more precisely estimated among girls. For girls children exposed to the program, height-for-age z-scores increased by 0.08 and 0.11; moreover, weight-for-age z-scores increased by 0.06 and 0.07. The point estimates for boy children are smaller in magnitude and insignificant for both height and weight. Finally, we find that the health benefits are larger for children exposed when they were under two years old, compared to children exposed between the ages of two and five. 

Our findings have direct relevance for policymakers considering quality improvements to municipal water systems and for the billions of individuals around the world who lack access to high quality drinking water. Transitioning the 2.2 billion people around the world who rely on unsafe drinking water is a necessary step towards achieving global development goals. A consistent challenge, made more difficult by more frequent and severe droughts, floods, and other natural disasters due to climate change, has been maintaining the infrastructure necessary to provide households with adequate drinking water in terms of quality and quantity. The Chlorination Strategy in Peru provides important insights for program design and implementation as well as impact evaluation to inform global policy efforts.

Author

• Emily L Pakhtigian, Pennsylvania State University
  Presenting Author