Charleston International Airport TSA (copy) (copy)

Departing passengers arrive at the security checkpoint at Charleston International Airport. File/Leroy Burnell/Staff

Bigger airplanes, more passengers and increased concession sales will land nearly 17 percent more revenue in the coffers of Charleston International Airport's oversight agency over the next 12 months.

The Charleston County Aviation Authority signed off Thursday on a $54.7 million spending plan for the next budget year starting July 1. That's about $8 million more than the previous 12 months.

"Most of the growth is from additional flights and more passengers," airport CEO Paul Campbell said. "Passenger growth drives increased revenue from parking, concessions, advertising and rental cars. As long as revenue is exceeding expenses, you are in pretty good shape financially."

The state's busiest airport completed its $200 million makeover during the past 12 months, adding more retail outlets and restaurants that help generate income. It also increased parking rates in November for surface spots and valet service, a move meant to help pay for a new 3,000-vehicle garage.

The proposed spending layout includes six new employees: two in ground transportation, two in engineering, and one each in information technology as well as planning and development.

"It might be a while before we bring those people on," Campbell said.

The budget includes an average 3 percent merit-based boost in pay for the 187 employees at the Aviation Authority. The number of workers doesn't include hundreds of others in federal security, concessions and airlines who are employed by separate public and private entities.

Among the bigger expenses for the airport next year will be about $2 million as its part of a new $18 million baggage-handling system and another $6.5 million in engineering work for a new road layout system and parking deck. The Transportation Security Administration will pay for most of the baggage system.

The Aviation Authority plans to rework the loop road in front of the terminal so more surface parking will be available while it displaces nearly 1,000 spaces during deck construction.

The road realignment, probably starting early in 2018, is expected to take the better part of a year while the parking deck construction will follow over the next 18 months or so, Campbell said. That would put the completion of the new garage sometime in 2020.

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Propelled by more flights to more destinations, airport passenger volume rose 6.2 percent during the first four months of 2017. The terminal recorded 3.7 million arrivals and departures last year. It's expected to handle 4 million passenger this year for the first time.

New air service is increasing boarding volume. For example, Southwest Airlines launched daily nonstop seasonal flights to Denver and St. Louis this month.

Campbell believes the popularity of those summer routes could translate into expansions at other times of the year if the demand holds up.

The airport is also in discussions with other airlines for new service, but Campbell said no announcements are imminent.

Reach Warren L. Wise at 843-937-5524 or