Richard N. Palmer
This research investigates how changes to floodplains in the Connecticut River Basin impact flood events. Climate impacted flows and increased development within the floodplain could lead to worsening flood events and less habitat availability for threatened species. Potential future conditions are evaluated through a wide range of scenarios to assess the range of possible impacts using a HEC-RAS 2D model. Three different flood events, 1-yr, 10-yr, and 100-yr, are evaluated for each scenario. Five metrics, Discharge, Depth, Time of Arrival, Flooding Duration, and Number of Buildings Flooded, are tracked for each scenario. These metrics are compared to select the ideal course of action given multiple potential objectives. For interested organizations, environment and human impact often have contradictory goals that decision makers must try to balance. The results of this analysis provide crucial information to help inform these decision makers. As floodplain restoration efforts increase, flood peaks decrease and habitat suitability improves. Restoration leads to reduced flood risk for downstream inhabitants, however, the number of impacted people residing in the floodplain increases. Flood duration also increases expanding the available suitable land for restoration focused efforts. Alternatively, as development in the floodplain grows, flood events increase flood risk for downstream inhabitants, while habitat suitability diminishes and the impact to floodplain residents decreases.