Grays Harbor Wind LLC (GHW) is proposing to develop a floating offshore wind farm offshore of west Grays Harbor County, Washington (Grays Harbor). The proposed GHW Offshore Wind Project (Project) would entail construction, installation and operation of a 1,000-megawatt (MW) offshore wind farm consisting of approximately 75 floating units, each containing a floating foundation and wind turbine generator (WTG). The Project location is approximately 25 miles (21.7 nautical miles [nmi]) offshore west of Grays Harbor, at waters depths of 360 to 700 feet. Floating offshore wind units installed in an ocean environment as part of the Project would interact with marine wildlife. This Study report provides an initial assessment, using publicly available data, of the Project effects, both negative and positive, on the marine environment. The scope of this assessment is limited by the fact that the Project development is presently at the conceptual level. Significant additional work is necessary to characterize ocean, seafloor, and environmental conditions; select appropriate floating offshore wind technologies; identify construction methods and locations; and assess facility locations, including electrical interconnection. Evaluation of the full range of potential environmental effects would be conducted following an award of a lease from the Bureau of Ocean Energy Management (BOEM) as part of the leasing, National Environmental Policy Act (NEPA)/State Environmental Policy Act (SEPA) environmental review and permitting processes. While this initial assessment uses best available public scientific information and current assumptions about the Project configuration, the effects discussed herein are based on the status of review to-date and may change as Project-specific details are developed.
This initial assessment of the potential environmental effects on marine wildlife resulting from offshore wind development in the waters off the coast west of Grays Harbor looked at the effects that may occur in the offshore wind farm area, along the electrical cable route back to shore, and within the Grays Harbor Estuary. Species of particular interest, including those of commercial importance or special environmental status, were reviewed to provide an initial assessment of potential environmental effects of the offshore wind development. Species abundance and geographic distribution were determined using existing, publicly available data sources based on scientific research by academic groups and state or federal agencies. Potential environmental effects on the species of interest were evaluated using knowledge generated by robust scientific research and observations from interactions between marine wildlife and human-built ocean structures. Environmental effects research from other locations and comparable species were used in the analysis when primary research was unavailable for the exact species located in the Project areas. Based on the conceptual level of Project design, the initial findings suggest that the environmental effects on marine life would be low to moderate in severity, and there would be potential to reduce them further by employing appropriate construction techniques or mitigation measures. Environmental effects would differ between the wind farm construction and operational periods. Effects during the construction period would occur over a short period of time, from days to weeks for some activities. Some temporary effects could be mitigated by timing the construction activity to minimize effects on the environment. Other effects from construction may cause a physical disturbance, but the impact would be limited to a small geographic area around the installation. Environmental effects on different groups of marine life could include the following:
- No long-term environmental effects on fish populations are expected from construction or operation.
- The greatest effects on fish are likely to occur within the wind farm at the offshore Project site once the wind farm has been constructed, resulting in increased numbers of fish within the wind farm and possibly increases in abundance outside the area.
- Gray whales and humpback whales may migrate near the Project area. Whales can be affected by temporary construction noise. Such effects could be mitigated by carefully considering noise mitigation (including construction timing) when it is applied to marine species as a whole. During operation of the wind farm, cable interactions (either mooring lines or other cables that are draped in the water column) with marine life have a very low probability of occurrence but could result in injury to a sensitive species.
- During construction of the electrical cable that connects the wind farm to the shore, there would be a temporary disturbance of benthic habitats, for example for shellfish. The habitat is expected to recover to natural conditions within months to a few years after cable installation.
- Loss of benthic habitat during the operational lifetime of the wind farm is expected to be limited to small areas around the anchors. The anchors also provide new hard substrate habitat that can be used by benthic organisms. Groundfish populations are unlikely to shift their range in response to the new substrate.
- The overall effects of climate change will increase pressure on marine wildlife in the Project area. Climate change will likely have an impact on marine wildlife in the Project area that is as large as, or greater than, that of an offshore wind development. Designing and permitting an offshore wind farm in the proposed area requires an extensive environmental review governed by state and federal environmental regulations, which will be conducted in due course and would include detailed environmental analysis and site-specific surveys.