The Port of Seattle Commission gave final design authorization Tuesday for an estimated $230 million renovation of the north satellite at Seattle-Tacoma International Airport to better serve passengers.

The project will include modernizing facilities, seismic upgrades, enhanced traveler amenities, three new gates and a new roof-top lounge for Alaska Airlines, soon to be the sole tenant in the north satellite, according to a port press release.

No port tax dollars will be used to pay for the project.

“This project directly addresses our Century Agenda goal to meet the region’s air transportation needs at Sea-Tac Airport for the next 25 years,” said commission President Gael Tarleton. “The north satellite is 40 years old and has had only limited upgrades. It’s due.”

The North Sea-Tac Airport Renovations will be an unprecedented working arrangement between the port and Alaska Airlines, Sea-Tac’s largest airline, according to the port. Alaska will work with the port throughout the project with the goal of improving its customers’ experience from airport drop-off to flight departure. Additional renovations will include various improvements to the main terminal, the C and D concourses, and the airfield.

Built in the late 1960s and early 1970s, the north satellite needs modernization, renewal or replacement of many of its basic systems. The renovations will provide significant annual energy savings with the heating/air conditioning (HVAC) upgrades and use of natural light. The project also includes seismic upgrades.

Alaska Air Group will continue to use concourses C and D for operations as well, which will receive upgrades to the current Horizon Air-operated facilities.

Design contracts will be awarded soon and visual renderings for the project are expected to be released by mid-2013. Construction is expected to start no later than winter of 2014 with completion in late 2016. [final construction schedules are still to be determined]

Funding for the project will come from a combination of airline rates and the Airport Development Fund. As with virtually all airport projects, no Port of Seattle taxes will be used. America’s airports are largely self-sustaining with revenues coming from fees paid by passengers, landing fees, space rental fees, and federal grants, according to the port.