OMAHA, Neb. (AP) — Upgrades are on the horizon at Omaha’s Eppley Airfield as it nears capacity following its busiest year ever.

About 4.6 million people traveled through the airport last year, a 6 percent increase from 2016. The increase is the biggest annual percentage jump the airport’s seen since 2005. It’s also the airport’s fourth consecutive year of growth.

New routes, more flights, and airlines flying larger plans contributed to the increased traffic, airport officials said. Omaha’s strong economy contributed to the demand for air travel, economists said.

“The airlines have definitely been willing to invest in Omaha,” said Eppley Executive Director Dave Roth. “And in Omaha, with the economy, folks are picking up that capacity and actually flying.”

Eppley officials will begin planning for improvements outlined in the airport’s 20-year master plan that’s driven by demand. Specific projects are trigged when the airport hits certain passenger milestones.

Projects to be considered include improvements to the north concourse and renovations to the airport’s main terminal.

“We’re in the right timing right now to start looking at this,” Roth said. “I don’t think we’re too fast or too slow. We’re working through this methodically to make sure we get the right process in place and also to build the right facilities.”

Roth expects Eppley will hit the plan’s next milestone of 4.75 million passengers this year.

The airport is currently constructing a new parking garage, which is expected to be completed in the spring. It’s also adding security lines to both security checkpoints and will likely renovate the existing parking garage.