More than 100 flights at Dallas-Fort Worth International Airport were delayed Thursday after non-essential employees were evacuated from a government air traffic control facility because of a sewage odor Thursday.

Lynn Lunsford, with the Federal Aviation Administration, told NBC 5 the Fort Worth Air Route Traffic Control Center continued to provide air traffic services at a slightly reduced rate as they rotated personnel in and out of the building.

Thursday afternoon officials said the odor was related to sewage and that plumbers were making repairs.

Lunsford added that air purifiers and fans were being used to circulate fresh air throughout the building.