As Vineyard Wind nears the building phase of its wind farm south of Martha’s Vineyard, fishermen have begun to clamor more than ever about the width of pathways between the giant turbines that will flesh out the lease area. In addition, they have voiced concerns about the effects of the turbines on the radar used by fishing boats to navigate.

Vineyard Wind has endorsed two-mile-wide corridors through the wind farm for marine traffic. However, fishermen, particularly from Rhode Island, are demanding four-mile-wide pathways.

“We know the fishermen in Rhode Island have asked for a four-mile corridor,” Martha’s Vineyard Fishermen’s Preservation Trust president John Keene told The Times. “We support the four-mile corridor.”

“The transit corridors aren’t big enough,” Rich Fuka, president of the Rhode Fishermen’s Alliance said. “A squid net is literally three-quarters of a mile behind a dragger.”

Fuka called Rhode Island the world nexus for squid fishing. He anticipated gear problems and navigation problems for the squid boats, as well as other vessels, should the corridors come to fruition at two miles.

“I just can’t imagine transiting through there at night in fog,” Menemsha lobsterman Wayne Iacono said. “Kind of scary to me. The further [apart] the better for safety.”

“Vineyard Wind is certainly amenable to discuss wider transit corridors,” spokesman Scott Farmelant said. Farmelant pointed out Vineyard Wind has already made a very big concession to reduce turbine density. It cut the number of turbine units from 108 to 84 by redrafting the construction and operation plan to utilize more potent and efficient turbines, he said.

“There are no established shipping lanes in the lease areas,” U.S. Coast Guard Petty Officer Zachary Hupp said. Automatic Identification System (AIS) historic data shows fishing traffic there, but not other commercial traffic, he noted.

“There is a traffic separation scheme just to the south of the lease areas,” he said. “There won’t be any restriction on the traffic that can go through there …”

The wind turbines will be charted and lighted, but absent a patent navigation hazard, the Coast Guard has no involvement in the transit corridors, he said. The layout is a collective decision by the leaseholders.

Iacono also pointed to radar problems he believes the turbines will make for the fishing vessels traveling in or near the lease area. “The blades really mess up the Doppler radar,” he said.

“This is a very big problem,” Fuka said. “As these blades spin, that rotation creates a field of energy. That shows up on radar as a mass. You can’t decipher it.”

Fuka said he fears the turbines will create a unified cloud on radar that will be tricky to navigate through.

A report by the National Weather Service indicated turbine energy signatures can produce a snowy cloud on government weather radar.

Radar challenges are definitely on the Bureau of Ocean Energy Management’s (BOEM) radar, BOEM acting director Walter Cruickshank told The Times in a media conference call Friday afternoon to announce a new lease area.

As of 1 pm Friday, Vineyard Wind was one of the winners in an 11-bidder auction for three new lease areas — 520, 521, and 522 —that comprise 390,000 acres of the Atlantic south of Martha’s Vineyard. Vineyard Wind won area 522, according to BOEM spokesman Solomon Odom.

The agency will “try to make sure that better solutions are found going forward to allow wind farms to be built with minimal interference to radar,” Cruickshank said.

James Bennett, chief of renewable energy programs for BOEM, said there are potential remedies for radar anomalies from turbines, though he referred to aviation and the military, as opposed to fishermen specifically: “They can be effectively ameliorated through different mitigation techniques, including distance from aviation areas. We also have issues for radar for military uses — which we are working very closely with the Department of Defense, the Department of the Navy, to ensure that these issues are not prohibitive as far as the development of the wind energy farms are concerned.”

“Vineyard Wind is very confident that by sitting with all the relative stakeholders and having open and productive conversations, that all these issues will be addressed to the satisfaction of all parties,” Farmelant said. “The impact of climate change as highlighted by the recent report of the United Nations underscores the importance of advancing clean energy projects like Vineyard Wind. The stakes are too high for civilization to consider anything other than a successful outcome.”