Managing the risk of flood-induced release of antibacterial pollution from livestock farms using agent-based modeling: insights from the 2021 sumas prairie flood event

The frequency of extreme weather events, such as flooding, wildfires and hurricanes, has increased due to global climate change. Recent reports and studies show potential for release and exposure risks associated with contaminants of emerging concern (CECs) during major extreme weather events. These events create conditions for releasing CECs into the environment, especially affecting surface and groundwater systems. Antibiotics are considered one of the largest categories of CECs, commonly used in livestock farms. Recent water quality measurements conducted in areas impacted by the November 2021 atmospheric river flooding in British Columbia revealed the release of this category of CECs into surface water bodies. This study employs the November 2021 Sumas Prairie Flooding as a case study and develops an agent-based modeling (ABM) tool for CECs release risk management using AnyLogic software. The model will aid in identifying mitigation, preparedness, response and recovery actions before, during and after flooding, ultimately minimizing the release and impacts of CECs. The findings indicate that implementing preventive measures, such as waterproof storage, elevated storage areas and sealed containers, can significantly decrease the amount of unprotected material likely to be released into the environment during a flood event by about 80%. This substantial reduction highlights the vital role of these measures in reducing environmental contamination following a flood.