Charleston County Aviation Authority on Tuesday proposed a $35.1 million spending plan for the fiscal year that starts July 1.

The budget is 28.3 percent higher than the current spending plan for Charleston County’s three airports, and it does not include any fee increases for parking or passenger fees.

The extra revenue will come from increased use of the airport as passenger numbers continue to climb, Airports Director Sue Stevens said.

She is requesting four new employees to add to the existing 145 people under her direction.

The budget proposal also includes 5 percent raises based on merit.

Some of the money will go toward the $150 million expansion of the terminal at Charleston International Airport. Those costs will be spread out over several years, including borrowing through bonds.

The aviation authority, meeting in a special budget session, did not adopt the spending plan for 2012-2013. A vote is expected when the board meets at 2 p.m. Thursday at Charleston International Airport.

Reach Warren L. Wise at 937-5524 or twitter.com/warrenlancewise.