Disentangling the complex response of rivers and floodplains to a shifting hydrologic regime for improved prediction of inundation and erosion hazardsproject period: 04 01 2024 through 03 31 2027IN…

The University of Vermont & State Agricultural College received a $499,109 Cooperative Agreement award from the U.S. Geological Survey under the Assistance to State Water Resources Research Institutes program (CFDA 15.805). The project, titled "Disentangling the Complex Response of Rivers and Floodplains to a Shifting Hydrologic Regime for Improved Prediction of Inundation and Erosion Hazards", will develop a tool to identify broad-scale patterns of flood hazards linked to changes in the size and frequency of flood events associated with a changing climate. Key activities include:

• Identifying zones along rivers in Vermont that are vulnerable to erosion or deposition, and understanding the rates and drivers of these processes
• Improving an existing inundation model to map flood hazards across the state on rivers draining more than 5.2 sq km and enable dynamic routing of flood hydrographs
• Integrating reach-based process-domain classifications into the inundation model to predict fluvial erosion hazards at regional scales

This research will generate publicly-available datasets and flood hazard maps to support targeted watershed planning and climate resilience efforts for communities in Vermont. The project will run from April 1, 2024 through March 31, 2027.

Disentangling the complex response of rivers and floodplains to a shifting hydrologic regime for improved prediction of inundation and erosion hazardsproject period: 04 01 2024 through 03 31 2027IN the northeastern united states, extreme precipitation events are becoming more intense andoccurring more frequently, increasing flood related hazards for many communities. Thesehazards may be associated with too much water running off the landscape or coming in from theriver (i.e., inundation hazards), or they may be associated with movement of the river channel orhillslope (i.e., fluvial erosion hazards). Fluvial erosion hazards can be significant in mountainouslandscapes and where people have historically altered rivers, leading to substantial impacts toroad, rail and crossing infrastructure in addition to buildings. While federal standards infloodplain mapping communicate inundation hazards, these assessments, which are oftenoutdated, exist only for limited river segments, and fluvial erosion hazards are rarely included. The proposed project will develop a tool to identify broad-scale patterns of flood hazards linked to changes in the size and frequency of flood events associated with a changing climate. The project will demonstrate this approach for the state of vermont, where the impacts of recent extreme flood events have been well documented, and perform the following activities:- identify the zones along the river that are more mobile and therefore most likely toexperience erosion or deposition and understand the rates of these processes and theirdrivers.- improve an existing low-complexity inundation model to map inundation hazards acrossstate-wide scales on rivers draining more than 5.2SQ KM and to enable dynamic routing offlood hydrographs.- integrate reach-based process-domain classifications within the low-complexityinundation model to predict fluvial erosion hazards at regional scales. This project will be one of the first to develop a predictive, data-driven model of erosion hazardsin a regional context. From this work, the project will generate publicly-available datasets of flood impacts ranging from recent extreme floods to more moderate floods. Flood hazard mapsdeveloped for future flow conditions will also be available to policy makers, state rivermanagers, and other stakeholders. The researchers anticipate the following broader outcomes from this work:- demonstrate the viability and transferability of low-complexity models built on high resolutionremotely sensed data and using data-driven approaches for understanding thespatial and temporal signature of flood inundation and erosion hazards.- identification of zones along river corridors in vermont that are likely to experienceenhanced vulnerabilities to flood hazards with a changing climate.- support targeted watershed planning activities for climate resilient communities.