Engineering With Nature

Engineering Practice Guide for Floodplain Benching – Case Studies

The Mores Creek restoration project in southwestern Idaho focused on repairing historical dredge mining impacts that degraded fish habitat, floodplain connectivity, and water quality. Using a nature-based design, the team restored a 6-mile reach by benching floodplains, installing large wood structures, stabilizing streambanks with soil lifts and native vegetation, and creating habitat complexity to support redband and bull trout. Hydraulic and sediment transport modeling informed new channel and floodplain geometries, while ecological targets emphasized large wood, pool creation, and riparian revegetation. Despite funding gaps for quantitative monitoring, qualitative assessments and community engagement provided ongoing stewardship.

The Garner Creek restoration project in Gwinnett County, Georgia, improved a 1,200-foot reach degraded by urban runoff, channel incision, and flooding. Restoration included stream realignment, floodplain benching, in-stream structures, and riparian buffer enhancement to reduce erosion, increase flood storage, and restore aquatic habitat. Stormwater BMPs, such as wetlands and swales, helped manage flashy urban flows, while community features like an outdoor classroom, walking trail, and river access supported education and recreation. Despite spatial constraints from adjacent school and soccer facilities, the project successfully balanced engineering, ecological, and social objectives to enhance water quality, habitat, and community use.