L&I report blames crane collapse on flawed base design

A state report issued today concluded a fatal Bellevue crane collapse in November was caused by a flawed engineering design of the mounting base.

The crane foundation, designed by Magnusson Klemencic Associates of Seattle, was designed to withstand only about one-fourth of the pressures the 210-foot tower crane required, the Department of Labor & Industries said.

The engineering firm is being fined $5,600, L&I officials announced. In addition, Lease Crutcher Lewis, the general contractor at the downtown Bellevue site, is being fined $9,200.

The report was issued at Bellevue City Hall this afternoon after a six-month investigation by L&I staff and outside experts.

Investigators interviewed people involved in the installation, reviewed documentation for the crane in downtown Bellevue and did engineering tests and metallurgical examinations to determine the cause.

The crane that fell Nov. 16 was installed on a 6-year-old parking structure, the start of a planned office-tower development that was later abandoned.

The crane was anchored to a steel I-beam structure instead of a concrete pad set in the ground, the standard mounting system.

Preliminary findings in the investigation pointed to the steel base as the probable cause of the collapse, a source said in February.

Investigators had determined operator error was not a factor, he said at the time.

The state Department of Labor and Industries examined several possible factors, including high winds and ice, which were determined not to be primary factors.

The accident killed Matthew Ammon, 31, who was in his top-floor apartment on 108th Avenue Northeast when the crane collapsed.

"I think it's obvious someone made some errors, and poor Mr. Ammon wasn't who made them," Matt Knopp, a Seattle attorney representing the Ammon family, said recently before the report was released. The family has not filed any lawsuits, awaiting the outcome of the L&I report.

The family went to the Legislature this year, seeking changes in the state's wrongful-death law and in regulations governing the siting of tower cranes, said Mike Wampold, a second attorney representing the Ammon family.

The collapse took place at Tower 333, at Northeast Fourth Street and 108th Avenue Northeast in downtown Bellevue. The building earlier was known as the Hines Bellevue Tower, after the Houston developer undertaking the project, and had been known as the Bellevue Tech Tower before its abandonment in 2001.

The previous work had included building part of an underground parking garage, which was abandoned. An earlier tower crane had been erected for that work but removed in 2003.

In February 2006, the city received a project description that noted the new work would be similar to the previous proposal, with an 18-story building, and eight levels of underground parking, with four levels of parking already completed.

By the fall of 2006, the new crane was in place, with a variety of construction firms working to complete the job for Hines.

Lease Crutcher Lewis was the general contractor, with LMN Architects as the building designer. Magnusson Klemencic Associates was the project civil engineer, with the crane leased through the Morrow Equipment and installed by Northwest Tower Crane.

The crane itself was made by Liebherr, a European manufacturer, and operated by the Ness Crane in a subcontractor to Morrow.

All of those companies declined to discuss details of the collapse over the ensuing months.

On the night of Nov. 16, the crane fell, killing Ammon, and some details began to emerge about its placement, including how it was mounted on steel I-beams that were part of the parking structure.

In January, a new crane was installed at the site, allowing construction to resume.

At the time, Bill Lewis, of Lease Crutcher Lewis, noted the new crane would be installed on a concrete footing on the ground, rather than on the steel I-beams of the earlier installation, with the new footing designed by Magnusson Klemencic and reviewed by a professional engineer.