By Kate Andries
As focus on renewable energy sources in Maryland expands into the Atlantic Ocean, special attention is being paid to the effects of offshore wind farm construction on marine mammals.
Noise generated from the construction of wind farms can damage the hearing of animals like sea turtles, sharks and a number of migratory whales, as well as possibly displace marine mammals from their original habitat.
“It’s a major focus for the offshore wind development community,” said Andrew Gohn, senior clean energy program manager with Maryland’s Energy Administration.
The Maryland Offshore Wind Energy Act of 2013, approved by Gov. Martin O’Malley in April, took effect on June 1. It establishes an application and review process for all proposed offshore wind projects.
According to a legislative analysis of the legislation, all turbines must be in accordance with the Energy Policy Act of 2005 that requires turbines to be located 10 to 30 miles off the coast of the state and sit on the outer continental shelf of the Atlantic Ocean.
This, researchers said, could pose a problem to the marine life that frequent the waters around offshore wind farms—especially when it comes to the noise created by the construction of turbine clusters.
Construction and operation plans for offshore wind farms submitted to the Department of the Interior would be required to go through an environmental impact process to make sure as little harm befalls the area as possible, Gohn said.
Construction would not begin before 2018, Gohn said, because developers cannot receive compensation for offshore renewable energy credits before then. However, researchers are already thinking about ways to mitigate harm once construction begins.
“If we’re talking about large wind farms all along a coast, bearing in mind that whales are migrating, and they’re moving through a gauntlet that they just can’t escape from…that’s what we’d want to avoid,” said Helen Bailey, research assistant professor at the University of Maryland Center for Environmental Science (UMCES).
Of greatest concern is the pile-driving necessary to install the wind turbines.
“That hammer is incredibly loud,” Bailey said.
Loud noise disturbances can cause both permanent and temporary hearing damage to animals that frequent the waters around construction sites, making it harder for them to find food and locate their mating areas. It can also cause behavioral disturbances that could drive mammals from a healthy habitat to a more unhealthy one, Bailey said.
If the noise is loud enough, Bailey said, it could kill them.
Bailey, whose expertise lies in habitat and environment modelling, is among a group of researchers who developed a method to assess the impact of construction noise on marine mammals.
A majority of research on the noise impact is being done in Europe, Bailey said, where offshore wind farms have been in operation since 1991. Much of what has been investigated across the pond is applicable to the Maryland coastline.
“You don’t want just to know what’s at the turbine site, you want to know what’s around it,” Bailey said.
And that’s exactly where researchers are beginning. Aside from the effects of loud construction noise on marine mammals—many of which are well known—studies are being conducted to look at the ocean habitat itself.
“[The] Department of Natural Resources is funding two surveys to obtain better information about marine mammal distribution and habitat use off our coast,” said Gwynne Schultz, of the DNR’s Chesapeake & Coastal Watershed Service, in a statement. “This type of information is needed to understand the impacts of offshore wind energy development.”
The surveys aim to establish an understanding of the distribution of wildlife in the area where proposed offshore wind farms would be constructed and should take about two years to complete, Schultz said. The surveys will also look at the abundance of certain animals, including sea turtles, different species of whales and certain species of birds.
“You want enough information to be able to distinguish between a natural response and one caused by a disturbance,” Bailey said.
This is not to say that researchers disapprove of the wind energy effort, as long as precautions are taken to protect the species that call the ocean home.
“At least with offshore wind, yes there’s noise, but hopefully it’s for a much shorter time,” said Bailey, of the noise of wind turbine construction compared to the noise generated by the oil and gas industry.
As a much cleaner alternative to oil and gas, offshore wind farms would bring about 850 jobs to the region and could supply enough energy to power a third of the homes on the Eastern Shore, according to the Maryland Energy Administration.
“Maryland is one of the early states [to invest in wind energy],” Bailey said. “It’s a good place to investigate and set the example.”