Year: 2024
Relevance
Onsite wastewater treatment systems (OWTSs) are a known non-point source of water pollution, but their underground location and lack of documentation make them difficult to include in watershed planning and water quality models. These systems are widespread in Mississippi and Alabama, posing growing concerns as many are aging, poorly maintained and largely unregulated. This increases the risk of water quality issues, particularly in coastal areas that face additional pressure from rising sea levels.
Response
Mississippi-Alabama Sea Grant funding brought together researchers, local stakeholders and practitioners to explore the complex human-environmental factors involved in integrating OWTSs into watershed planning. Collaboration and data sharing played a key role in developing the model. The resulting data and model outputs are being finalized and will soon be available through an interactive online map, providing easy access for decision-makers and the public alike.
Results
These findings have important implications for how professionals map, model and understand the role of OWTSs as non-point sources of water pollution. Contrary to past assumptions that OWTSs are uncommon in urban areas, the results reveal notable densities within municipal boundaries. This suggests that OWTSs in cities may be contributing to water pollution more than previously recognized and should not be overlooked in future planning and management efforts. Link to map: https://aub.ie/owtsdensity.
Recap
Geospatial analysis paired with machine-learning revealed where onsite wastewater treatment systems (OWTSs) are predicted in Mississippi and Alabama's coastal counties. By combining verified OWTS locations with socio-environmental data, the model showed surprisingly high OWTS densities inside municipal limits, which contradicts the common belief that urban areas host few of these systems.