What Impacts do Hurricanes have on Water Quality?

Hurricanes have affected the fresh waters of the east coast of the United States throughout the region's history. These storms cause changes in water quality through various mechanisms such as damage to infrastructure, excessive precipitation, and storm surges, that contribute to both localized and regional flooding during and immediately after the hurricane. As developed and urbanized areas have become more prevalent, the opportunities for contamination of water resources during these events have grown. In this study we attempt to quantify and conduct a regional assessment of these changes in water quality through the study of 14 hurricanes (e.g. Harvey, Sandy, Irma). To reach our goal, (1) we collected water quality datasets (i.e. turbidity, dissolved O2, Nitrates/Nitrites, pH) for 829 stations from the USGS's Water-Quality Historical Instantaneous Data for the Nation database, (2) we extracted a various range of contributing variables for each investigated station (e.g. land use, precipitation amount, hurricane strength on the Saffir-Simpson hurricane wind scale), and (3) we constructed and employed a machine learning based procedure to determine which contributing factors have the highest impact on water quality as well as the magnitude of the response corresponding to the contributing factors. This technique yields a better understanding of the relationship between hurricanes and their impact on water quality. This method also provides a predictive capability where the impact of future hurricanes can be modeled and estimated before impact, contributing toward a better management of water resources in hurricane prone areas.