DENVER — Denver International Airport may have to add 10 months to its projected 3-year renovation project. A new monthly report from the contracting team showed some of the concrete samples from the airport’s terminal floor tested weaker than expected.

Great Hall Partner’s forecasted delay is 209 business days. The original completion date was Nov. 3, 2021. The new estimate is Aug. 30, 2022, according to the December report released last week.

The report shared concerns the weaker-than-anticipated concrete could push back future phases when crews need to start erecting steel on the Jeppesen Terminal floor.

After testing about half of the concrete samples last fall, the report said some of the concrete extracted from the floor had lower ‘compressive strength’ results, or ability to withstand heavy loads without breaking, than the airport planned. Approximately 94 percent of the concrete cores were tested when the report was issued, according to Great Hall Partners.

The report made clear the delay is a preliminary estimate. The projected schedule could change after more review and mitigation efforts. DIA explained concrete testing will continue through April. By then the airport will have a better idea of what the delay might be.

The contracting team said they will still work on other parts of the project in the meantime.

Work on the Jeppesen Terminal began last summer. When construction is complete, the terminal will look completely different and the concourses will have new gates.

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The renovation is part of a $1.8 billion deal with Spain’s Ferrovial S.A. Denver City Council signed a 34-year contract with the private company in August 2017.

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