Poster #32 - Who Benefits from Clean Water? Evidence from Peru’s Rural Sanitation Program Rollout and Infant Feeding Status

• In Event: Friday Poster Reception

Abstract

Diarrheal disease remains a leading cause of mortality among children under five, particularly in low- and middle-income countries where exposure to unsafe water, poor sanitation, and environmental contamination remains widespread. Despite substantial progress in reducing diarrheal mortality and expanding access to improved water and sanitation services, many countries remain in a mid-transition stage with pronounced within-country inequalities. Peru exemplifies this pattern. National rates of diarrheal disease and inadequate sanitation have declined, yet rural areas continue to experience persistent service deficiencies and a disproportionate burden of childhood diarrhea. This raises an important question: under what conditions do sanitation investments translate into measurable child health gains? Evidence suggests that large investments in water, sanitation, and hygiene can increase access and service quality, but health effects are often modest and depend on local context, service reliability, coverage, and remaining contamination pathways. That is, infrastructure buys part of the protection, but it does not guarantee better health outcomes. Exclusive breastfeeding may be an important source of heterogeneity in this relationship by reducing infants’ exposure to potentially contaminated liquids and foods. If environmental contamination is a main driver of diarrhea, sanitation improvements may yield larger reductions among non-exclusively breastfed infants, who face more direct exposure to unsafe food and water, than among exclusively breastfed infants, who already receive partial protection through feeding practices. 

In this paper, we estimate the effects of Peru’s National Program on Rural Sanitation (PNSR) on early childhood health and examine whether those effects differ by exclusive breastfeeding status. The PNSR, launched in 2012, expanded and rehabilitated rural water systems, with documented improvements in access to supply networks, chlorination, and service continuity. We combine child-level data from the Peruvian Demographic and Health Survey (ENDES) with PNSR administrative implementation records and 2007 census locality population data. To address nonrandom program placement, we exploit the program’s population-based eligibility rule, which prioritized rural communities above 200 inhabitants, and apply a fuzzy regression discontinuity design at the locality threshold. Because eligibility changes the probability of receiving a sanitation project but does not perfectly determine treatment, eligibility at the cutoff serves as an instrument for program exposure. Our design estimates local causal effects for children living in communities near the eligibility threshold. We then test feeding-status heterogeneity to assess whether the health returns to sanitation differ between exclusively and non-exclusively breastfed children. 

Preliminary findings suggest that exposure to PNSR is associated with better child health outcomes, including lower diarrhea prevalence and improvements in anthropometric measures, although estimates remain imprecise and are not consistently statistically significant across outcomes. The emerging patterns point to potentially meaningful differences by breastfeeding status, motivating further analysis of how household-level protective practices may shape the returns to rural sanitation investments. This study moves beyond average program effects and examines who benefits most from rural sanitation investments. The findings have direct relevance for policymakers seeking to close persistent rural health gaps in low- and middle-income countries.

Author

• Beatriz De Araujo Silva, Pennsylvania State University
  Presenting Author