Draft Bank Protection/Stabilization White Paper

In Washington State, construction or performance of work that will use, divert, obstruct, or change the natural bed¹ or flow of state waters requires a Hydraulic Project Approval (HPA) from the Washington Department of Fish and Wildlife (WDFW) (Revised Code of Washington [RCW] 77.55). The purpose of the HPA program is to ensure that such activities are completed in a manner that prevents damage to public fish and shellfish resources and their habitats. To ensure that the HPA program complies with the Endangered Species Act (ESA), the WDFW is considering preparing a programmatic, multispecies Habitat Conservation Plan (HCP) to obtain an Incidental Take Permit from the U.S. Fish and Wildlife Service (USFWS) and the National Oceanic and Atmospheric Administration (NOAA) Fisheries Service (known as NOAA Fisheries). WDFW’s objective is to avoid, minimize, or compensate for the incidental take of species potentially covered under the HCP resulting from the implementation of permits issued under the HPA authority. In this context, to â€�"take” means to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect or to attempt to engage in any such conduct.

To evaluate the feasibility of and develop a scientific foundation for the HCP, the WDFW has commissioned a series of white papers that will review and summarize the best available science for up to 21 HPA activities that could be included in the HCP.

This white paper compiles and synthesizes existing scientific information on bank protection and stabilization projects, referred to here as bank protection projects. Bank protection structures are defined by WDFW as �"permanent or temporary structures constructed parallel to and immediately adjacent to the shoreline and landward of the shoreline for the purpose of protecting or stabilizing the bank (e.g., bulkheads, retaining walls, etc.).”

The objectives of this white paper are:

1. To compile and synthesize the best available scientific information related to the potential human impacts on potentially covered species, their habitats, and associated ecological processes resulting from the construction and operation of bank protection structures permitted under the HPA authority
2. To use this scientific information to estimate the circumstances, mechanisms, and risk of incidental take potentially or likely resulting from construction and operation of various types of bank protection structures
3. To identify appropriate and practicable measures, including policy directives, conservation measures, and best management practices (BMPs), for avoiding, minimizing, or mitigating the risk of incidental take of potentially covered species

The literature review conducted for this white paper identified seven impact mechanisms associated with the construction and presence of bank protection that could potentially affect aquatic species being considered for coverage under the HCP (�"potentially covered species”). These mechanisms describe modifications to habitat arising from activities that can be temporary or permanent in duration. The impact mechanisms evaluated in this white paper are:

• Construction Activities
• Channel Processes and Morphology
• Substrate Modifications
• Habitat Accessibility
• Aquatic Vegetation
• Riparian Vegetation
• Water Quality

Following a brief description of bank protection activities and existing Washington Administrative Code (WAC) provisions pertinent to bank protection structures and their installation, the 52 aquatic species being considered for coverage under the HCP are described. Based on this information, the potential direct and indirect impacts to the potentially covered species or their habitats are discussed. In addition, the potential for cumulative impacts is discussed. Next, the risk for incidental take of potentially covered species is qualitatively estimated and the applicability of existing WAC provisions to address take mechanisms is reviewed. The white paper then identifies data gaps (i.e., instances in which the data or literature are insufficient to allow conclusions on the risk of take). The white paper concludes by providing habitat protection, conservation, mitigation, and management strategies consisting of actions that could be taken to avoid or minimize the impacts of bank protection structures.

¹ Bed is defined as the land below the ordinary high water line of the state waters, but does not include irrigation ditches, canals, stormwater runoff devices, or other artificial watercourses except where they exist in a natural watercourse that has been altered by humans.