Repetitive Flooding in Riverine Towns: Understanding Responses, Barriers, and Challenges for the Future

Climate change is predicted to increase the intensity of precipitation events and increase inland flooding in the United States in the coming decades (Allan et al., 2020; Easterling et al., 2017; Kerlin, 2019; Mallakpour & Villarini, 2015). Unlike coastal communities, which have seen increased attention in the face of climate change, riverine communities have received far less attention (Jongman et al., 2012). This is despite a long history of repetitive riverine flooding and associated responses and barriers to flood mitigation. Important insights can be drawn from towns that have endured repetitive flooding and how they have responded.

This thesis explores riverine towns with repetitive flooding, the similarities and differences in their flood responses and barriers to mitigation, similarities that can be deduced for other riverine towns, and how policies may be improved to better support them.

To answer these questions, results were compared from semi-structured interviews and historical research from four case study towns in the United States: Harrisburg, Pennsylvania; Freeport, Illinois; Ellicott City, Maryland; and Athens Borough, Pennsylvania. Firstly, results showed several barriers to flood mitigation, including a lack of institutional capacity, challenges with regionalism, and insufficient federal flood mitigation assistance. Secondly, results showed that mitigating flood risk from multiple flood profiles, managed retreat, and structural flood mitigation solutions are proving successful for some riverine towns as flooding events increase in severity. Lastly, results showed that current federal programs must better fully support smaller riverine towns needing funding for flood mitigation, and modifications to existing programs and new programs are necessary to support their unique circumstances. From a resource allocation perspective, this thesis highlights the need to devote more resources to riverine towns with repetitive flooding to help them mitigate the worst effects of flooding in the face of increasingly worse storm events due to climate change.

Naylah Canty

Thesis Advisor: Mary Anne Ocampo