MEMPHIS (AP) — All incoming and outgoing passenger flights at Memphis International Airport were canceled Friday due to terminal closures caused by system-wide water pressure issues, the facility said.

A press release from the airport said it has experienced ongoing pressure issues throughout the week, but on Thursday night levels dropped to the point where passenger operations weren't viable.

At least 79 passenger flights were canceled Friday, according to FlightAware, a flight tracking and data platform website.

Memphis Light, Gas and Water issued an order Thursday for residents to boil water before they use it after frigid temperatures led to water main ruptures and problems at pumping stations.

The power and water company in Shelby County, which includes Memphis, said low pressure in the system and breaks in water mains could allow harmful bacteria to contaminate the water supply. The order applies to nearly 260,000 homes and businesses.

The airport requires a reliable water supply for restrooms, operations, food and beverage, and the airlines. The terminal will remain closed until water pressure can be restored. The airport said it's working with the utility company to discus solutions and remain updated on repairs.

"This is a last resort for MEM," said Scott Brockman, President and CEO of the Memphis-Shelby County Airport Authority. "A passenger airport cannot function without a safe and dependable water supply, which we do not have at this time."

Cargo operations haven't been affected.