NEWPORT, Ore. – The development of wave energy facilities off the coast of Oregon could have significant impacts on the physical ocean and the ecological communities it supports, according to a newly published report, but most of those impacts are only beginning to be studied.
The report is a summation of findings from a workshop held in October, 2007, at Oregon State University’s Hatfield Marine Science Center in Newport. The workshop brought together dozens of scientists to explore potential issues ranging from the impact of buoys on waves to the effects of electromagnetic fields on fish. The report is available online available online.
“The workshop and the subsequent report provide a framework for the key issues we need to address in marine ecosystems as wave energy develops in the Pacific Northwest,” said George Boehlert, director of the Hatfield center and editor of the report. “The high priority issues that we need to address deal with potential impacts on marine mammals and seabirds, the effects on the physical environment and changes to the benthic habitat.
“There also is a need to explore the cumulative effects of wave energy parks as the technology develops and commercialization efforts scale up.”
The scientists concluded that wave energy buoys should not be placed in “sensitive areas” of the near-shore environment, particularly in depths of less than 40 meters. They also suggest that a system of buoys could result in wave reduction, which could affect the movement of sand up and down the coast.
Tuba Ozkan-Haller, an associate professor in OSU’s College of Oceanic and Atmospheric Sciences, and a consultant to the report, said specific impacts on beaches would depend largely on the number of buoys, and how and where they are deployed.
“If there are enough buoys and they are close together, that could result in the general reduction of waves along the coast,” said Ozkan-Haller, an expert in near-shore oceanic processes. “However, depending on spacing between the buoys and their distance from shore, the buoys could lead to a channeling effect that potentially could create rip currents on nearby beaches. As soon as we see the projected size and deployment of a wave energy facility, we can begin to create models that will tell us more about the physical impacts and could then potentially design deployment configurations that minimize such impacts.”
The report also identifies potential impacts on the pelagic environment, benthic environment, fish, seabirds and marine mammals. Among the issues:
• Pelagic Habitat: The buoys may attract forage fish species, which could attract larger fish. Minimizing entanglement of sea turtles in loose lines is crucial and some scientists are concerned about potential electro-magnetic field effects, though little research has been done in that area.
• Benthic Habitat: Wave energy facilities likely will affect local currents that may have impacts on larval distribution and sediment transport. Biological growth on buoys, cables and anchors may also affect the sandy environments where they will be placed.
• Fish: An increase in forage fish could draw in larger predators, which could affect the complex marine ecosystem. If structures are large enough, they could affect migration corridors for salmon, crabs, sturgeon, whales and other creatures.
• Seabirds: Lighting and above-water structures may result in collisions and attraction to buoys, and could alter food webs. More research is needed on bird abundance, night-time behavior, migration patterns and “hotspots” of heavy bird concentrations.
• Marine Mammals: Major concerns were raised about the types of mooring cables that would be used and how they may lead to entanglement. Baseline data is needed on marine mammal species and their distribution in the affected regions. Monitoring behavior to explore how whales and other mammals interact with wave energy facilities will be critical.
Boehlert said many of the issues can be addressed through research. He said it will be important for scientists and the wave energy industry to collaborate as work progresses. Mitigation of environmental concerns can be achieved through design of the devices, as well as appropriate siting, researchers said.
“The results of the workshop already are being used to guide the ecological committee of the Oregon Wave Energy Trust as it moves forward in funding the most important projects in the ecological arena,” Boehlert said. “The report also will be a starting point for ecological concerns that will be addressed by the new Northwest National Marine Renewable Energy Center.”
“Right now, wave energy technology is ahead of the related ecological research,” Boehlert added. “The sooner we can address the questions the better, because the potential benefits from a clean, renewable energy source like ocean waves are enormous.”
The Hatfield Marine Science Center workshop was supported by numerous state and federal agencies, industry and others.
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