Investigators look into loosened bolts, weather after fatal Seattle crane collapse

As Mercer and surrounding streets are reopened, investigators are looking into causes behind a fatal crane collapse in South Lake Union that killed four people on Saturday.

RELATED: SPU student among 4 killed in Seattle crane collapse

Investigators are currently honing in on a handful of aspects regarding the incident, chief among them, the five contractors responsible for the crane. That includes the general contractor, the crane provider, the employer of the tower crane operator, and the two companies involved with disassembling the crane.

“There was a sub-contractor that was taking the pieces of the tower-crane apart, and there was another sub-contractor operating a mobile crane that was lifting and moving those pieces down so they could be moved away to somewhere else,” said Tim Church, a spokesman with the Washington State Department of Labor and Industries, the agency leading the investigation.

Essentially, cranes are built and disassembled on-site, and re-certified for safety every time they’re built back up.

According to Church, the L&I has two lead investigators, both of whom are former crane operators. Over the next six months, they will be gathering computer data, talking to witnesses, and reviewing video evidence.

“Once we have a conclusion, we will meet with the companies involved, we will spell out what we found, we’ll let them know if we found any safety violations, if they’re being cited or penalized, and once we do that, that information is public for everyone to see what happened,” described Church.

GLY, the contractor on the project responsible for the crane, noted that it is “cooperating fully” with local authorities as they continue to look into the incident.

In terms of specific factors that led to the collapse, L&I is looking at winds at the time — said to be gusting over 20 miles-per-hour — and if crews followed proper procedures for loosening bolts.

One crane safety expert told KIRO Radio that because the crane came down in sections, it’s possible that some of the bolts were either too loose, or removed altogether.

The Seattle Department of Transportation is also facing scrutiny. Director Sam Zimbabwe was pressed on why Mercer Street wasn’t closed while the crane was being taken apart.

“We understand the perimeter that the contractor needs to do the work that they do, and then we work with them on exactly when and what traffic control plans need to be put in place,” said Zimbabwe.

On Saturday, Zimbabwe said that some streets around the building were closed to allow crews to get equipment in and out. Mercer Street was not one of them.

Mercer reopens to commuters

All lanes of Mercer Street at the site of the incident were closed through the weekend.

Those lanes were reopened in time for the Monday commute around 3 a.m., while the southbound mainline off-ramp to Mercer was reopened approximately two hours after that.

Vulcan and GLY contractor crews worked overnight to clear debris and assess the safety of surrounding buildings. Meanwhile, SDOT crews repaired damage to the street by using a form of temporary asphalt. While that was good for the short term, it may beget more repairs in the near future.

“We basically used a short-term asphalt that we are going to need to go back and make more permanent, so we’re going to be looking for a good opportunity to do that, which will at some point in time mean more closures for Mercer,” SDOT spokesperson Ethan Bergerson told KIRO Radio.

SDOT noted in an early-Monday blog post that the cleanup and repair on Mercer was completed earlier than anticipated. As of the morning, all city streets affected by the crane collapse have been reopened.

Tragedy strikes on a Saturday

Three men and one woman were killed when a crane collapsed at the intersection of Mercer Street and Fairview Avenue North in Seattle on Saturday afternoon.

A Seattle Fire Department spokesperson said that all four people were dead by the time responders reached the site of the collapse.

Two of the fatalities were ironworkers in the process of disassembling the crane, while the other two were each in separate vehicles on the street. One of the fatalities down on the street was a freshman at Seattle Pacific University, Sarah Wong.

Travis Corbet was identified Sunday evening by his wife Samantha as one of the ironworkers killed in the crane collapse. Corbet and his wife live in Oregon and he served in the Marines.

The two other victims have yet to be identified.

Six total cars were crushed, and four other people were injured. One person was treated on-scene, and three were transported to Harborview Medical Center.

The three transported to the hospital were a 28-year-old man, a 25-year-old mother, and her 4-month old infant. All three were conscious when they arrived at Harborview. The Seattle Times reports that the mother and infant were discharged from the hospital on Saturday. The man remained at the hospital through the weekend in satisfactory condition.

According to The Seattle Times, the crane in this latest collapse sat atop a building that’s part of 607,000 square-foot project expected to house Google. Construction began in 2017 and was expected to be complete this year.

KIRO 7 TV contributed to this report

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