When it rains, it pours: Wastewater infrastructure in the face of natural hazards and social vulnerability

Abstract

Wastewater infrastructure is increasingly vulnerable to climate change and sea-level rise, particularly in coastal regions. Existing research also highlights disparities in access to wastewater infrastructure across different socio-demographic groups. This study investigates the spatial distribution of two distinct yet complementary types of wastewater infrastructure—septic systems and sanitary sewer pump stations—within the context of natural hazards and social vulnerability in Miami-Dade County, Florida, United States. By incorporating the National Risk Index that measures physical risks into our analysis, we demonstrate that a disproportionately high number of wastewater infrastructure per capita are located in census tracts with high natural hazard risks, underscoring the challenges of future infrastructure maintenance. Additionally, using the Social Vulnerability Index that measures social needs, we identify a negative correlation between the number of wastewater infrastructure per capita and social vulnerability, revealing evident social inequities in access to critical wastewater treatment services. We also apply spatial regressions, including spatial lag and error models, to show the presence of spatial dependence. Analyzing the availability of wastewater infrastructure through the lens of natural hazards and social vulnerability provides new insights into inequality assessment. Targeted interventions based on both physical risks and social needs are essential for enhancing urban resilience in the face of climate change.