From our sister site The SeaTac Blog:
Flooding closed part of Sea-Tac Airport on Tuesday morning, July 25, 2023, disrupting travel for many.
A spokesperson for the Port of Seattle said that “a large flood of water” was discovered near ClubSEA in the south portion of Concourse A Tuesday morning, and the area where it happened was closed off so workers could stop and clean the mess up.
It is unknown at this time what caused the flooding or what its origin was.
Airlines including United, JetBlue and AirCanada use Concourse A, according to the Port of Seattle website.
Here’s video showing the flooding courtesy @JRiley0788: