Federal officials say they are looking at new studies of fish species that migrate off the coast of Long Island and their potential reactions to electric pulses from the transmission cables of the proposed South Fork Wind Farm, in response to concerns raised by fishermen and the East Hampton Town Trustees.
Concerns about how fish might react to the electric magnetic field, or EMF, given off by the wind farm’s foot-thick power cable when it comes ashore have become the main objection from the East Hampton Town Trustees and the South Fork’s commercial baymen.
Fishermen rely on the annual migrations of fish through the relatively shallow waters within a couple of miles of the shore on their way to summer haunts in the bays. They worry that even if the EMF pulses given off by the sort of cable that would connect to the wind farm were minor—as studies suggest—the subtle impulses could be enough to divert fish in their migrations and away from the near-shore areas.
In the earliest discussions of the issue over the last several months, representatives of Deepwater Wind have presented the results of studies conducted at the existing wind farm off Block Island and by scientists around the giant offshore wind farms in Europe, as well as laboratory tests that show the effects of EMF on migrating fish to be inconsequential.
But fishermen and their supporters have said those studies are of little reassurance to them, since they involve different scales, different types of sea floor or different species of fish than those that are of the utmost importance to local baymen.
“What they tested in Europe is not that relevant. What they tested at Block Island, with a cable one-quarter the size of this, is not that relevant,” said Gary Cobb, an East Hampton man who has been reviewing the work done thus far on EMF and other details of offshore wind development on behalf of fishermen. “And you need several years of data for any of it to be useful.”
Earlier this winter, the Town Trustees issued a call for more studies—along with an aggressive demand for financial support from Deepwater for fishermen who are impacted by the project—to examine the effects of EMF on fishes that migrate to Long Island in summer.
Scientists from the federal Bureau of Ocean Energy Management said this week that they have reviewed the Trustees’ requests and are exploring ways to incorporate such studies into the environmental review process for the wind farm, which will include more than a dozen federal and state agencies.
BOEM officials said that they are looking at new data collection efforts in the wild, as well as ways to use existing data from previous studies, looked at from new angles, to shed light on some of the questions about how fish can be expected to react to the cable.
“We think we can use some of the data that we have already,” said Brian Hooker, a fisheries biologist for the bureau’s Office of Renewable Energy Programs. “We’ve partnered with the DEC to set up an acoustic array in the [New York Bight]” to track fish fitted with special tags, he said.
Mr. Hooker noted that other groups of scientists have also been compiling data for years about striped bass migrations, and that the fish regularly travel up the Hudson River and East River as well as the Chesapeake Bay, all of which have a numerous underwater power cables running through them between population centers. The data from such research could be re-purposed to explore the context of such species’ interactions with undersea cables.
The BOEM has already done a substantial amount of study of EMF effects, the officials said. Mary Boatman, the bureau’s chief of environmental studies, said that the agency has been looking at the issue since it started its renewable energy program in 2006, both through original scientific studies and by compiling existing scientific research.
The agency has done open-water tests with both A/C cables, like the one that will be used to connect the wind farm to shore, and D/C cables, like the large power transmission cables that run from Long Island to Connecticut and New Jersey. The most recent study, on the Cross Sound Cable, showed that lobsters and skates—species selected because they have been found to be especially sensitive to EMF—detected the electromagnetic halo around the cable from farther away than expected, but didn’t necessarily react negatively to it.
“We could tell by their movements that they were responding to the [EMF signature], but that doesn’t mean it translates into a barrier that they won’t cross,” Ms. Boatman said. “We saw no evidence that the rays would not cross it.”
Ms. Boatman noted that A/C, or alternating current, cables are understood to have a much lower EMF signature than the D/C, or direct current, cable that was used for the lobster and skate study. The larger D/C cables had been expected to be what most offshore wind farms would use to send their power ashore, but advances in technology have brought A/C cables back to the fore in such uses.
At a recent meeting with the Trustees, Mr. Cobb pointed to the Cross Sound Cable study specifically, noting that while the more powerful D/C cable would carry a larger signature than the wind farm connector, the extent to which animals detected the field was greater than expected—highlighting that unknowns remain the rule with EMF.
The 400-page BOEM report on the effects of EMF on lobsters and skate itself acknowledges that very little is currently known about the effects of EMF at environmental levels on the migration habits of fish. Could even faint levels of EMF in the water column be enough to change the course of a fish’s migration?
“If the fish can detect this stuff from 15 or 18 feet away, and it’s only 30 feet deep, they’re not going to swim up and over it,” Mr. Cobb said after a recent Trustees meeting. “Will they swim through it? I don’t think we know that.”
The federal agency says it will continue to develop new ways to examine what impacts the South Fork Wind Farm and the large number of offshore turbines that are expected to be erected off the East Coast in the coming decade might have on marine species that are part of one of earth’s largest migrations and drive billions in economic growth.
“We have taken [the Town Trustees] suggestion and put it into our studies planning process,” Stephen Boutwell, a spokesperson for BOEM, said in an email this week. “The proposed study would look at existing scientific information with respect to the key fish species identified by the town and their interactions with existing cables (Neptune, Cross Sound, etc.). However, being able to conduct this work depends on multiple factors, including availability of funds.”