Reconfiguring an airport the size of O'Hare, including building four new runways—without disrupting the 68 million passengers that use it annually—involves challenging staging and logistics. The construction team had to relocate a railroad, a cemetery, cargo facilities and a stormwater retention basin. One new runway will be opening in October, while another is in an active site- preparation stage.
When the overall $6.6-billion O'Hare Modernization Program is complete, O'Hare will have six east-west parallel runways and two crosswind runways. "Once you get to the paving, it's long, straight and flat," says Frank Grimaldi Jr., assistant commissioner of the Chicago Dept. of Aviation. "But getting there, coordinating, having no impact on aircraft operations or safety—those are the hard parts," he says. Each of the construction sequences is very closely coordinated with airfield operations.