A sinkhole was discovered at New York’s LaGuardia airport on Wednesday, shutting down a runway while emergency crews sought to determine its cause and how to fix it.

In a post on X, LaGuardia, which handles domestic travel, said the sinkhole had been discovered at about 11am “near runway 4/22” while the airport’s operator was conducting its daily morning inspection.

“The runway was immediately shut down, and emergency construction and engineering crews are onsite to determine the cause and complete necessary repairs as quickly and safely as possible,” the post said.

New York’s Port Authority warned that travelers should “expect delays and cancellations, particularly with forecast thunderstorms expected later today, and are strongly encouraged to check directly with their airlines for the latest flight status information”.

LaGuardia is built on land reclaimed from the surrounding bay in the 1930s, and sits on an area that once featured homes, hotels and an amusement park.

Airports are increasingly challenged by uneven ground sinking along runways, according to a 2025 report. San Francisco international airport is reportedly sinking the fastest. Overall, about 3.5m sq meters of runway experiencing significant sinking, and nearly 14,000 sq meters at high risk of structural damage, the report noted.

The closure of LaGuardia comes nearly two months after an unrelated crash of Air Canada flight struck a Port Authority fire truck on the same runway as the sinkhole. Two pilots were killed.

At 3pm EST, the FAA’s airport monitoring service reported that due to expected thunderstorms a traffic management program is in effect for arriving air traffic, causing some arriving flights to be delayed an average of 1 hour and 37 minutes.