San Diego’s main airport is about to see some big changes.

Terminal One at Lindbergh Field is slated for a major renovation that will replace the 18-gate facility with a 28-gate structure. The San Diego County Regional Airport Authority also plans to add new parking garages and airplane-maintenance facilities.

The hope of the authority is to extend the life of the airport to 2040, increasing the annual passenger count to 14.5 million up from its current 9.2 million.

A formal proposal is hoped for in the fall, and costs of the new terminal are expected to range from $2.1 billion to $2.6 billion.