Until now, most work on the $3.6 billion project to rebuild Salt Lake City International Airport has been out of easy public view. That is about to change.

The airport will redirect its roadway beginning Aug. 16 so that it will take motorists between the new terminal and new parking garage — giving up-close views of exterior construction progress.

The rerouting also will cut a third of a mile off of the current exit route, which has changed often during different phases of construction.

The coming rerouting is needed to give crews the space to install exit facilities for the new airport parking garage.

Airport officials say the new path will be in place until Sept. 15, 2020, when the first phase of the rebuilt airport is scheduled to open for business.

The current airport was designed to handle only 10 million passengers annually, but the airport last year served nearly 25 million — so the city is building a new, modern facility to replace it essentially on top of the existing airport without closing it.

The “airport is incredibly busy with the 15 largest passenger volume days in the history of the airport all occurring in the last year, many of those in the last two or three months,” Airport Director Bill Wyatt told the Airport Advisory Board this week.

When the first phase of the rebuilding project opens next year, “We’ll probably have passenger volume that we didn’t expect to have until about 2022,” Wyatt said.

Wyatt said most of the growth is coming from local passengers, not those merely making flight connections here.

“Airports typically are great barometers of the local economy,” Wyatt said. “The economy of the region is incredibly strong, and as a result of that more and more people are showing up at our front door” — and next week can drive by and look at the airport’s new front door.

Among new facilities are a larger parking garage, a gateway building between it and a new terminal and two new parallel concourses that avoid bottlenecking operations It will have larger screening facilities that use faster processes, and the largest Sky Club used by Delta Air Lines anywhere. It will have more seats in waiting area, with more power plugs for passengers’ electronics, and more restaurants, stores and restrooms.

It will even have a large side area for greeting arriving passengers — expected to be used mostly for large parties welcoming returning missionaries.