This winter has been hard on RDU already, as the airport runs low on deicing chemicals

Back to back winter storms this month have “severely depleted” the supply of chemicals that Raleigh-Durham International Airport uses to keep its runways free of snow and ice, according to airport officials.

The RDU Airport Authority held an emergency meeting late Tuesday to authorize airport staff to buy more. The board approved spending $241,770 to buy materials from Cryotech Deicing Technology.

The chemicals — the liquid Cryotech E36 and the solid Cryotech NAAC — are used on runways and taxiways, but not on airplanes. The airlines buy their own deicing chemicals and apply them to their aircraft.

RDU stocks up on the chemicals before the season starts, then orders more after each storm, said Bill Sandifer, the airport’s chief operating officer. Two winter storms, Izzy and Jasper, brought snow and ice to the Triangle on consecutive weekends.

“We typically get resupplied in three to five days, and if you look at the historical weather patterns in North Carolina, you don’t have storms this close together,” Sandifer told members of the Airport Authority. “So I think we’re seeing a little bit of an anomaly.”

The chemicals RDU ordered after the first storm, Izzy, arrived Tuesday, Sandifer said. It’s not clear that the second order authorized Tuesday will come in time for the next round of winter weather expected to begin late Friday.

Sandifer said he has “serious concerns” about handling another winter storm so soon. He said RDU would use the chemicals it has on runways and taxiways, to keep the airfield open.

“We’ll do the best job that we can,” he said. “We do have some, and we will prioritize where we put it.”

The chemicals RDU uses are not salt, which is corrosive to planes, so the airport can’t simply ask to borrow some from the N.C. Department of Transportation or a nearby town.

RDU used much of its chemical stockpile during the most recent storm, Jasper, which lasted longer than Izzy. During that storm, a Delta Air Lines plane with 19 passengers on board rolled off a taxiway into a grassy area after landing from Washington, D.C., at about 9 p.m. Friday. No one was injured, but the airport’s main runway nearby was closed.

That forced the airport to clear the alternate runway, closer to Terminal 1, of snow and ice. Several flights were diverted until that work was completed. The main runway reopened the following afternoon, after the Delta plane was towed to a parking area.