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Haley & Aldrich wins prestigious state and national ACEC Engineering Excellence Awards for its innovative work on Seattle’s Climate Pledge Arena

Climate Pledge Arena

Burlington, Mass., April 7, 2022 – Haley & Aldrich announced today that the company has won the American Council of Engineering Companies (ACEC) of Washington’s prestigious Engineering Excellence Platinum Award — the highest state honor — and a national Grand Award for its work on Seattle’s Climate Pledge Arena. As a result of winning a Grand Award, the Climate Pledge Arena project is in the running for the ACEC’s Grand Conceptor Award, which is the year’s top engineering achievement and will be presented at the Engineering Excellence Award Gala in Washington, D.C., on May 24.

The Washington state awards program recognizes projects that represent a wide range of engineering achievements and demonstrate the highest degree of skill and ingenuity. The national Grand Award is presented to a select few engineering consultancies and recognizes U.S. projects that show innovation, complexity, achievement, and value.

“These awards are a tremendous honor for the entire Climate Pledge Arena project team,” said David Winter, the principal-in-charge for the project and General Manager of Haley & Aldrich’s Hart Crowser Business Unit. “This project presented a number of significant and unusual challenges and our team collaboratively and productively worked through those during the height of the pandemic. The result is a tribute to everyone involved.”

The project team needed to build the new facility on the downtown site of the old arena, originally constructed for the Seattle World’s Fair. However, there was a significant catch: The existing arena featured a unique 57-year-old, 22,000-ton concrete roof designed by architect Paul Thiry in the “Seattle Modernist” style and was deemed a landmark that needed to be used for the new arena.

The team’s greatest challenge was to develop a design and monitoring approach to ensure the roof stayed in place and in one piece while lowering the playing surface and doubling the size of the arena below. The brittle roof structure could only move one-quarter inch without damaging it. Building a new arena under its own roof had never been done before, and each step of the project required new solutions. Haley & Aldrich developed an approach that allowed the roof to be supported without movement during existing arena demolition, excavation, and new arena reconstruction.

During the height of the COVID-19 pandemic, the schedule didn’t relax. The project team safely adapted and the Climate Pledge Arena, the first net-zero professional sports venue, opened on time and ready for the puck to drop on the 2021-2022 National Hockey League season.

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