Report: Nets at Atlantic salmon farm were fouled with kelp, mussels

Aerial footage of salmon net damaged during eclipse’s high tides

Aerial footage of a net holding more than 300,000 salmon that broke amid the eclipse's high tides near the San Juan Islands.
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Aerial footage of a net holding more than 300,000 salmon that broke amid the eclipse's high tides near the San Juan Islands.

Investigators probing the collapse of an Atlantic salmon farm that sent 160,000 invasive fish into the Salish Sea last summer are examining mussels and other sea life coating the nets as a cause.

Photographs obtained by The Seattle Times under a public records request show portions of the nets at Cooke’s farm were so fouled with kelp, algae and especially mussels that the net was no longer visible.

Mussels rained down on the dock as the nets were lifted with a crane for disposal. Heaps of mussels on the dock were so high, they had to be scooped up with a front-end loader.

Cooke is required under the terms of its lease with the state to maintain its farms in a clean and safe condition. And Cooke had long known it needed to tackle the problem of drag at the farm, one of three it owns at Cypress Island. The farm faced broadside into the current instead of into it, like the other two. The company planned to reposition the farm to lessen the forces of drag on the structure it had already identified as its top priority for replacement.

But first, it wanted to take its harvest, scheduled in September, of about 3 million pounds of Atlantic salmon in the nets – 305,000 fish in all.

From net to anchor

Keeping the nets clean is important because fouling changes the way they behave under water in tidal currents. A net creates drag in the water, as current is impeded by its webbing. Any sea life or other material that covers and fills the webbing adds to that drag, said Parker MacCready, professor of oceanography at the University of Washington.

Ultimately, he said, a net can so impede the flow of water it acts like a sea anchor – and even a wall.

The bigger the blockage, and more the current, the greater the drag. “Drag is real, drag matters,” said Jim Thomson, senior principal oceanographer and a fluid mechanics expert at the Applied Physics Lab at the University of Washington.

Reviewing some of the same photos investigators have focused on, Thomson said, “I would not be surprised if the drag forces are at least doubled, and possibly much more, with so much fouling.”

Notes obtained by The Seattle Times that were written by state investigators from their interviews with Cooke employees after the incident show employees confirmed that two of three machines used to clean the nets were out of service and being repaired, reducing the ability to keep up with biofouling, a problem that intensifies in the summer.

“Net washing machines were down, this kept putting them behind on keeping up with removing mussel growth,” supervisor Brent Bruner told investigators, according to their notes.

“Nets need more cleaning in the summer. Broken net washers affected the cleaning schedule. Fouling at Site 2 was 7 out of 10, it is usually 4 out of 10,” notes from investigators’ interview with Cooke employee Matt Fitzgerald recorded. Other employees also attested to problems with net maintenance.

The farm itself, in Cooke’s judgment, suffered corrosion and metal fatigue and was at the end of its useful life.

Joel Richardson, vice president for communication of Cooke Aquaculture, declined to comment on the nets or maintenance issues at Cypress Island.

“We are cooperating fully with the regulatory agencies as their investigation is underway,” Richardson said in an email to The Seattle Times. “As such, it would not be appropriate for me to provide comments.”

Months of mussel buildup

State investigators focused early on the issue of fouling, as hunks of the destroyed fish farm were hauled to the surface after the collapse. Investigators cut off and preserved chunks of net covered in mussels for evidence.

“It’s possible these animals played a significant role in the failure of net pen #2,” Dennis Clark, assistant division manager for the Washington Department of Natural Resources wrote investigators on Sept. 10, assessing the same photos of heavy mussel growth on the nets later obtained by the Times.

Brian MacDonald at the WDFW advised Clark to weigh representative samples of the mussels to determine the wet weight the animals would have added on the nets.

Clark demanded access from Cooke to its remaining two farms at Cypress Island, Site 1 and Site 3, to perform a video survey of the nets at those farms.

The agency also was seeking to determine if Cooke is maintaining those farms in good order and repair, in a clean, attractive, and safe condition, as required by the state’s lease. If not, the agency can cancel the company’s lease – as it did in December at the company’s farm in Port Angeles, a termination the company is fighting in court.

The mussels on the Site 2 nets were estimated to be six to nine months old by WDFW staff, emails obtained by the Times show. That, for investigators, also raised the question of adequate maintenance by Cooke.

Sky Guthrie, Cooke’s Cypress Island Manager, told investigators there were problems with net maintenance before Site 2 first broke free from its moorings in July, less than a month before the complete collapse.

With just one working net-cleaning machines left, employees tried other means.

Innes Weir, Cooke’s general manager in Washington, told investigators employees continued cleaning the nets by lifting them and sucking kelp off using a vacuum device. The company brought in equipment from its other farms, and got the nets 80 percent clean. “Staff are aware of the problems caused by fouling,” he told investigators.

Still, if fouling is scored on a scale of 1-10, 2-3 is ideal, but it was probably more like 8 after July, Guthrie told investigators, according to their notes.

“Mussel buildup on floor,” he added.

There also were ongoing structural issues at the farm, including cracks in the walkways, Eric Brown, Cypress Island Assistant Manager told investigators. “It continued to try to curl under, during both ebb and flood tides.”

Catastrophic collapse

Employees’ interviews also shed new light not only on the seriousness of the first trouble at Site 2, which broke half its mooring lines in July and started to drift, but the mayhem of the total collapse less than a month later.

“It’s really bad,” Daniel Farias said on the phone to Guthrie, the site manager, after three to four anchor lines broke Aug. 19. He saw walkways buckling, and the entire structure bending and twisting.

Guthrie recognized an emergency was happening and called in managers from around the company. “Arrived on site, observed extensive damage, Site 2 moving toward Site 1,” Guthrie told investigators. “ Very dynamic … Flood tide, north side and shore side anchors failed either broken or drug, moving south/southwest toward Site 1.

“Walkways on east end buckling … main bridge disconnected, pens disconnected, failing.”

Guthrie deemed the farm too unsafe for staff to board. And over the next couple of days, “things got worse.” Top priority for Cooke as the disaster unfolded was keeping the failing farm from careening into its Site 1 farm, also full of fish.

“Continued to deteriorate up the system. Walkways would buckle at the hinges. Two compromised cages, then four, then six … after that, walkways were flipping, it was catastrophic, at that point it was a salvage operation.”

Investigators from multiple state agencies are expected to report their findings on the spill Tuesday.

Meanwhile the state Legislature is considering several bills to phase out, or immediately terminate, Cooke’s operations in Washington. The chairmen from 21 Washington tribes also sent a letter to every state lawmaker on Jan. 18 requesting that Atlantic salmon open-water net-pen farming be shut down in Washington as soon as possible, to protect native salmon in Puget Sound.

Cooke has hired lobbyists, spokespeople, and lawyers to defend its operations, the 181 jobs the company sustains in Washington, and its investment in the farms.

The company has invested more than $70 million in the farms, and intends to upgrade and expand its operations, Cooke executives have told legislators in hearings convened to consider phasing out or shutting down their operations.

Washington is the only state on the U.S. West Coast with open-water Atlantic salmon net pens in its public waters. California and Alaska ban the practice, and Oregon has no Atlantic salmon farms.

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