Natural Channel Design: A Nature-based Solution for Floodplain Management & Watershed Resiliency

Location

United States

Start Date

Nature-based solutions (NbS) are increasingly a requirement and/or focus of federal natural disaster recovery and mitigation funding programs. They provide valuable tools toward resiliency of the affected communities and watersheds in the face of more frequent and intense weather-related disasters caused by climate change. However, federal guidance on NbS for flood risk mitigation and watershed resiliency in fluvial settings traditionally focuses only on prescriptions external to the stream channels themselves, such as land conservation, wetland restoration, onsite stormwater management, and floodplain reconnection/restoration.

In 2021, the U.S. Army Corps of Engineers’ Engineer Research and Development Center published “International Guidelines on Natural and Nature-Based Features for Flood Risk Management”, which for the first time presents river/stream restoration as an appropriate NbS measure for fluvial flood risk management. However, even in this guidance, stream restoration is presented as one of many NbS prescriptions that should be considered in fluvial flood risk management, based on a holistic, watershed approach, and may not be emphasized or prioritized to the extent warranted for the alluvial systems that provide the primary drainage and flood control infrastructure for the majority of U.S. cities.

This presentation will present and discuss stream restoration’s place within current federal NbS guidance documents and make a case that stream restoration should be the highest priority in the use of NbS in flood risk mitigation and watershed resiliency efforts for a majority of U.S. cities. Examples of successful applications in various urban and suburban watershed settings will be presented to support the position.