An environmental sampling and community-driven methodology to understand and address risks from sanitary sewer overflows and basement backups

The release of untreated sewage from failing wastewater systems occurs globally, exposing residents to a range of negative physical and mental health outcomes. These circumstances might be particularly prevalent in underserved populations that often have inadequate infrastructure due to structural disinvestment. These communities face scenarios of persistent exposure to raw sewage in their homes, often containing waterborne pathogens and antibiotic-resistant (AR) bacteria. While most studies focus on understanding sanitary sewer overflows (SSOs) and backups at the watershed scale, we provide a transdisciplinary and comprehensive approach that assesses SSOs and basement backups, including social aspects, infrastructure burdens, and pathways of AR bacteria at the household level. Through our 40 home pilot studies, we implemented this study in Baltimore, Maryland (2022). We developed a five-step environmental sampling and community-driven methodology that combines urban planning, engineering, and public health, including (1) resident survey, (2) visual household inspection, (3) environmental sample collection and processing, (4) household and microbiological lab analysis, and (5) sharing results with participants. Our current efforts have utilized this framework to expand into three counties in Maryland. This study highlights the need to explore the impact of the built environment on public health and potential solutions to SSOs in underserved communities.