The massive chunk of Seattle’s Pier 58 that collapsed Sunday during demolition work plunged into Elliott Bay in a matter of seconds, leaving almost no time for two workers to escape, dramatic new video of the incident shows.
Trees and heavy concrete planters plummeted into the water, pulling a 4-ton fountain, its concrete pump station and a concrete terrace in behind them. The culprits in the collapse were steel-and-concrete support piles that were in a state of severe deterioration, officials said Tuesday.
It was a near-miracle that the workers sent into the water at the city-owned park suffered only minor injuries as the debris tumbled down.
Five workers were able to avoid the collapse, including some who were standing on the boardwalk portion of the pier, which is supported by timber piles and which remained intact.
In the video, recorded from a Seattle Aquarium building adjacent to the site, those workers can be seen running to help their crew mates. The victims landed just south of where most of the concrete dropped, officials said.
“It was a traumatic experience” for the crew, Jessica Murphy, construction manager for the city’s Office of the Waterfront, said at a remote news conference Tuesday. “We were very lucky” that the injuries weren’t worse.
“I cannot overemphasize how extraordinarily fortunate we are there was no additional injury, with elements as big and heavy as they were” crashing down, added Marshall Foster, the office’s director.
Built in 1974, Pier 58 is located between the Great Wheel and the Seattle Aquarium. The section that collapsed, at the north end of the pier, was supported by steel-encased concrete piles. But those piles were determined to be breaking apart this summer, destabilizing the pier, Foster said.
The pier, a public space with benches and telescopes also known as Waterfront Park, was discovered last month to be separating from the Elliott Bay Seawall. That’s why the city ordered the pier’s demolition on an emergency schedule, Foster said.
“The entire Pier 58 structure is in a uniform state of failure,” said an Aug. 13 report that recommended the pier be removed within 90 days.
At the time of the collapse, the workers were saw-cutting a 20-inch-thick concrete wall away from the pier, Foster said. They were working to remove weight as quickly as possible from the area supported weakly by the steel-encased piles, Foster said. The workers had removed 20,000 pounds Saturday.
The concrete piece the workers were saw-cutting when the collapse occurred was secured with a chain to a crane. That piece hung in the air when the rest of the area dropped into the water.
The entire pier spanned about 48,000 square feet before Sunday’s mishap; an estimated 15,000 square feet of material collapsed, Murphy said.
“We couldn’t support the whole pier with the crane,” she said. “There was a lot of weight with all that concrete.”
The saw-cutting work was “non-structural,” Foster said when asked whether bad planning or a misstep in the demolition was responsible for the scary collapse. The pier “was in an active movement already,” he said. Saw-cutting puts less stress on structures than other methods, Murphy added.
There was a digital system set up at the site to monitor the pier’s movement, with an automatic alarm for emergencies, Foster said.
“It did go off,” Murphy said. “The audible alarm was heard. We also had somebody there with an air horn to ensure the sound was heard by everyone.”
The two workers couldn’t scramble away in time. In an extended version of the video, shown Tuesday by the city, they could be seen walking around the danger zone just before the collapse.
Loss of support
The demolition work was accelerated late last week after Pier 58 began separating from the seawall more quickly, Foster said. The structure had been moving a quarter inch each week; that rate nearly doubled last week, he said.
The city was particularly concerned about the pump house and a Seattle City Light electrical vault stationed in the same area, directly next to the aquarium. The vault provides electrical service to the aquarium, including exhibits, Foster said. The collapse narrowly missed the vault, leaving the aquarium and its electrical service undamaged, he said.
The debris that sank will now need to be extracted, according to the city, which is still evaluating the wreckage and has yet to develop a new plan. The concrete blocks will need to be broken up in order to be retrieved from the water, said Murphy. It’s not yet clear whether the area is safe for divers, she said.
State and federal workplace safety inspectors have opened investigations into the incident, The Seattle Times reported Monday.
The Washington State Department of Labor and Industries and the U.S. Occupational Safety and Health Administration will investigate the city, as well as the demolition’s contractor and a subcontractor that were involved with the project before a chunk of the pier plunged into Elliott Bay.
The contractoris Orion Marine Contractors and the subcontractor is Evergreen Concrete Cutting. They’ve declined interview requests, deferring to the city. Seattle intends to keep Orion Marine on the project, Foster said, describing the state and federal investigations as “not at all uncommon in a major incident like this.”
“We have a good team working on this project,” Murphy said.
The city knew Pier 58 was at risk long ago, due to regular reports on the structure by consultant Seattle Structural. In 2011, most of the steel-and-concrete piles were at only 25% capacity, displaying severe rusting in the “splash zone” just above the tide and barnacle crusting below, according to a report at the time. The report recommended annual checkups.
By 2016, 52% of the pier’s timber piles were seriously decayed, up from 3% in 2006, according to another report, which predicted some timber piles would fail by 2021 and which also warned about the steel piles under the fountain.
“The north terrace in particular has serious reinforcing steel corrosion that may not be accelerating at this time but is ongoing,” the 2016 report said.
Seattle had long intended to remove and replace Pier 58 with a new park as part of a broader waterfront overhaul that already has included the construction of a new seawall and last year’s deconstruction of the Alaskan Way Viaduct.
Until recently, the plan was to demolish the pier in 2022; metal plates spanned the joint between the pier and the seawall, accommodating some movement.
But the city decided a change in schedule was needed in early August, when workers checking an unrelated issue discovered the pier had moved several inches away from the seawall, leaving a visible gap.
“It appears that the loss of vertical support” under the fountain “is causing the structure to lean to the southwest,” said the Aug. 13 report by Seattle Structural that the city made public for the first time Tuesday.
The steel-encased piles below the fountain “are failing at their head connections,” creating sideways pressure against the timber section of the pier, the report added.
“The timber framing is not designed for these high sustained lateral loads and will likely continue to yield. Eventual failure of the resisting elements is likely. …. The consequence of this failure would be the collapse of the pier.”
The pier was closed to park-goers last month and the city selected contractors for the project, using emergency contracts that were exempt from bidding requirements. The city picked Seattle Structural to design the demolition, and picked Orion Marine to carry out the removal, which began last week.
Seattle initially said the demolition would cost $4.3 million and last until early 2021. Officials shared its contracts with Orion Marine and Seattle Structural with reporters for the first time Tuesday, along with their Pier 58 removal plan.
The Pier 58 fountain, designed by Seattle artist and architect James FitzGerald and cast a year after his death from bone cancer by his widow and artistic collaborator, Margaret Tomkins, features abstract shapes that resemble blocky trees.
Before the collapse, the city planned to incorporate the fountain into the new Pier 58 park. That’s still the hope, Foster said Tuesday.