The cost of expanding Austin’s airport terminal and the surrounding tarmac has gone up about 46 percent over the past year as city officials broadened the scope of the project.
The Austin City Council on Thursday will consider a $289 million contract with Hensel Phelps Construction Co. to add nine gates in a 70,000-square-foot expansion of the terminal’s east wing, along with a greatly extended “apron” area for airliners.
A year ago, the estimated construction cost for the terminal and apron was $198 million.
The council will also vote on doubling, from $18 million to $36 million, the authorized amount for M. Arthur Gensler Jr. and Associates, which is designing the expansion.
All told, the project’s construction cost is now about $350 million, airport Executive Director Jim Smith said in a memo to the City Council earlier this month, including money for project management, testing, inspection, permitting, bond financing and some equipment and furniture.
The larger price tag came from a number of changes to the project over the past few months, several of them stemming from larger planes using the airport.
For starters, the apron area south and east of the terminal will be expanded by about 27 acres, about double what was originally intended, said Shane Harbinson, an assistant director at the airport. The airport has begun to host larger Boeing 787 planes, rather than the Boeing 737s that have tended to use Austin-Bergstrom, he said, and expects even more of the bigger planes as time goes on.
The 787-class planes have a wingspan of 197 feet, he said, versus about 125 feet for a 737. That broader reach requires a more expansive area for taxiing the planes between gates and runways, Harbinson said. Beyond that, the airlines and the Federal Aviation Administration were asking for more room to park planes overnight.
The added tarmac, in turn, meant that a 116,000-square-foot detention pond near the apron, which otherwise would have been left in place, will have to be moved and built about 20 percent larger to store and treat runoff water and de-icing material. Empty buildings remaining from the airfield’s days as a U.S. Air Force base will be demolished to make way for the new pond.
In another change, the project will include replacing the existing terminal’s roof, Harbinson said, as well as utilities and lighting within the building.
The demolition and construction work should begin later this fall, officials said, with the overall project done by early 2019. The work on the terminal’s east end, according to city documents, likely wouldn’t begin until the fall of 2016.
When that happens, first one and then later a total of three airline gates will be closed for construction. But Harbinson said the plan includes temporarily having one gate replaced by an old-style operation in which passengers go down to the tarmac level and board planes via “air-stairs,” the mobile stairways familiar from past decades. Then temporary, long jetways will be installed to take passengers around the construction to four gates, meaning that there will be one more gate during construction than exists now.
The 16-year-old airport has seen rapid passenger growth over the past six years, and is now exceeding its 11 million-a-year passenger capacity, a figure that includes both boarding and arriving customers. Expanding the terminal and apron, officials said, will bring the capacity to 15 million passengers a year, enough to keep the airport operating properly until at least 2025.
To pay for the work, the airport borrowed $130 million in 30-year revenue bonds in December, Harbinson said, and plans to sell an additional $220 million in 2016. That money will be paid back primarily using revenue from the $4.50 “passenger facility charge” levied on each departing ticket from the airport, along with airline rental fees and concession revenue, Harbinson said. That $4.50 fee is already at its maximum amount, he said, but revenue from it grows as passenger volume increases.
The airport also plans to apply for FAA grants each of the next four years, and it has been in discussion with federal regulators about the project and those grants. Harbinson said the airport will seek $3 million to $10 million in each of those years.