INVESTIGATING WILDFIRE-INDUCED CONTAMINANT IMPACT ON GROUNDWATER FLOW AND QUALITY IN LAHAINA, MAUI

On August 8, 2023, a rapid and devastating wildfire swept through Lahaina, Maui, causing extensive destruction and environmental disruption. This event introduced a variety of contaminants into the environment, significantly impacting groundwater flow and quality. The combustion of vegetation, structures, vehicles, and various materials released hazardous chemicals, such as pyrogenic PAHs and heavy metals, along with nutrients like nitrogen and phosphorus. This project aims to understand the immediate and long-term impacts of these contaminants on groundwater flow and quality in the affected regions.

To achieve this, we established two experimental transects in the affected area. One transect involves installing piezometer wells to monitor groundwater table fluctuations in response to tides, while the other transect includes multiport sampling wells for groundwater quality measurements at various depths. Based on our field measurements, we established a variably saturated and density dependent groundwater flow and salt transport model to characterize groundwater flow and solute transport in Lahaina beach environments.

The combined field observations and groundwater modeling provide a comprehensive understanding of potential pathways and the persistence of contaminants from wildfires in Lahaina’s coastal beach environments, if there are any. These findings provide insights into assessing the vulnerability and resilience of coastal aquifer systems to wildfire-induced contamination, aiding in the development of effective mitigation strategies for affected communities.