15 Oct 2024

Vegetation Establishment and Management in USACE Floodwater Detention Basins: Greens Bayou Flood Risk Management Mitigation Project

Abstract: This report documents efforts by the US Army Engineer Research and Development Center (ERDC) in assisting the US Army Corps of Engineers (USACE) Galveston District (SWG) in native vegetation establishment design, propagation, installation, monitoring, and adap-tive management for the mitigation requirements of the Greens Bayou Flood Risk Management Project. Specifically, to provide (1) a vegetation establishment design ensuring development of sustainable native plant communities compatible with flooding and drought events; (2) suitable native aquatic, wetland, and woody plants for project use; (3) implementation of plantings; (4) monitoring and adaptive management; and (5) vegetation establishment reports and an operations and maintenance manual for long-term vegetation management of the project site. The Greens Bayou Project included approximately 3.7 miles of channel conveyance improvements and 138 acres of storm-water basin detention storage to reduce flooding damage by safely storing excess stormwater during heavy rain events and slowly releasing it back into the bayou. The completed basin was designed to hold approximately 1,400 acre-ft, or 538 million gal., of stormwater. Vegetation establishment, monitoring, and adaptive management efforts in the mitigation features discussed herein occurred between 2019 and 2023.