Abstract: As part of the US Army Corps of Engineers (USACE) Continuing Authorities Program (CAP), Section 206 projects focus on restoring aquatic habitats for the benefit of fish and other wildlife. From 2017–2021, USACE Engineer Research and Development Center–Environmental Laboratory researchers in the Aquatic Ecology and Invasive Species Branch (ERDC-EL EEA) at the Lewisville Aquatic Ecosystem Research Facility (LAERF) collaborated with USACE Galveston District, The Nature Conservancy, US Fish and Wildlife Service, National Park Service, and local nonfederal sponsors—Brownsville (Texas) Public Utility Board and the City of Brownsville—to study restoration methods on former, naturally cut-off, channels of the Lower Rio Grande River. These aquatic ecosystems, locally termed “resacas,” are home to endemic plants and animals and are thus an important natural resource of national interest. This technical report documents the planning, design, construction, monitoring, and adaptive management activities throughout the Resaca Boulevard Resaca Section 206 Aquatic Ecosystem Restoration project. Methods and results for invasive species management—primarily Brazilian peppertree (Schinus terebinthfolia)—and aquatic and riparian vegetation establishment in endemic Texas ebony resaca forest, subtropical Texas palmetto woodland, and Texas ebony/snake-eyes shrubland habitats are discussed.