The Port of Seattle is finally nearing the finish line of what’s been a politically harrowing and expensive process of adding a third runway at Sea-Tac Airport.

Just this month, the airport turned jurisdiction over the 8,500-foot-long strip of grooved concrete to the Federal Aviation Administration for tests of the new runway’s lighting and instrument landing systems in preparation for its November opening to commercial traffic.

For the port, the process of planning and building the runway has been a 19-year ordeal.

That process began in 1989 when the idea of adding a third concrete strip to the two existing ones at Sea-Tac first surfaced. It continued through the community decision-making process and the numerous court battles with a determined and well-funded opposition. That opposition, which included a coalition of cities near the airport, won important victories to soften the impact the runway would have on surrounding communities.

Now, four years after those court fights ended with the airport winning permission from regulators to build the strip, it stands nearly ready to receive its first official aircraft.

Sea-Tac and two other airports, Chicago’s O’Hare and Washington, D.C.’s Dulles – which are opening new runways the same day – will approach the White House for President Bush to inaugurate the runway with a landing of Air Force One, his aircraft, and with a ribbon-cutting ceremony.

Not only has getting the runway built proved to be time-consuming, but it also has been expensive. The final bill hasn’t been totaled, but Sea-Tac spokesman Perry Cooper said preliminary indications are that it might come in under the revised estimate of $1.2 billion. The original estimated cost was $430 million.

BUILDING THE THIRD RUNWAY

Standing at the end of the white and unmarked ribbon of concrete recently, Steve King, construction manager for the project, surveyed the runway. There was obvious pride in his demeanor as he pointed out what had to done to complete what to the untrained eye might seem to be a simple and straightforward project.

The third runway, even if you don’t consider the political minefield the port had to cross to win permission to build it, was a major feat.

Much of that complication came from the site, which was a deep wooded valley west of the existing runways populated by dozens of homes, crossed by multiple creeks and peppered with lakes and wetlands.

Buying land: In the end, the port purchased some 500 properties including about 400 homes to make way for the north-south runway and its approaches. It relocated those residents and took careful inventory of the environment.

Leveling the land: To create the level plateau on which to build the runway, the port brought in 13 million cubic yards of fill and relocated three million cubic yards of soil already on the site.

To hold that fill in place, the airport construction team created three huge retaining walls, the largest of which is 1,430 feet long and some 130 feet tall.

The gravel and the soil used to create that plateau had to pass forensic inspections to ensure it was clear of contaminants and similar in composition to the rocks and soil already at the site.

“We had to find gravel that originated in the same place in Canada and that was transported here by the glaciers as the gravel that was here on the site,” said King.

The reasoning behind such a requirement is that water that leached through the fill would pick up minute traces of the minerals in the fill, drain into the creeks and confuse or damage native salmon returning to those creeks.

Transporting the fill: A special fleet of dump trucks burning ultra-low-sulphur diesel carried fill from select sites 20 hours per day, six days a week during the height of the filling process. The port built two dedicated exits from highways 518 and 509 to handle the truck traffic. Those trucks were washed after dumping each load and the wash water collected and recycled.

While the port was building the new runway, it extended the grassy overrun areas on the existing runs to 1,000 feet on each end to meet FAA regulations. The new runway and the two runways’ overrun areas required the port to relocate a road at the north end of the airport and move Miller Creek.

Runway construction: The runway concrete surfaces are 17 inches thick and made of specially formulated concrete. Beneath that concrete is 8 inches of crushed rock and 2 feet of gravel. That concrete contained fly ash, a byproduct of burning coal. That fly ash replaced about one-third of the cement that would have been used in the concrete mix. Using fly ash reduced the energy costs of the concrete.

Easing environmental impact: During construction, the port collected and treated some 579 million gallons of stormwater from the site. It was filtered with a product made from crab shells before being reintroduced into the creeks.

The airport must create an environment in the former housing area near the runway, said Cooper, that is welcoming to fish and mammals but not to birds. Birds are the nemesis of airports because they can be sucked into aircraft engines and cause accidents.

Port wildlife experts have even watched a pair of hawks that live near the airport and have removed and relocated their young once they were old enough to fend for themselves, said Cooper.

The breeding pair is accustomed enough to the airport to know to avoid the runway areas, but the port’s wildlife officials fear that the young birds of prey would accidentally fly into the path of an airliner.

The airport’s stormwater retention ponds are covered in nets to keep ducks and other aquatic birds away. The natural lakeshores are planted with vegetation that is not attractive to birds.

To compensate for the loss of waterfowl habitat – some 20 acres of wetlands that were filled in creating the third runway – the port acquired and enhanced 65 acres of wetland area near the Green River in Auburn. Port contractors have planted some 151,000 native plants on those acquired lands and others nearer the airport.

What it means to passengers: The third runway is located 2,500 feet west of Sea-Tac’s present main runway, a distance that will allow incoming aircraft to land on the new runway and the runway closest to the terminal simultaneously in bad weather. The middle runway of the three is only 800 feet west of the runway closest to the terminal, a distance that’s too close to allow two streams of traffic when visibility is impaired. The third runway will then make its presence felt most dramatically when the weather is poor, allowing two streams of traffic instead of the one currently allowed.

NEXT PROJECTS AT SEA-TAC

The opening of the third runway won’t end construction at Sea-Tac. Several major projects are under way or will begin soon:

Main runway reconstruction: Once the third runway is done, work will begin early in 2009 on a overhaul of the airport’s longest runway, the easternmost of the three. Parts of that nearly 12,000-foot-long runway date from the airport’s opening in 1944. It was overlaid with a new surface in 1952, 1963, 1972 and 1992. Now the airport needs to raze the whole runway, build new drainage and electronic systems, install new lights and then restore it to service. The process is expected to close the runway for six months. The budget is $78 million.

Rental car terminal: The port has begun clearing a site at the intersection of International Boulevard and Highway 518 north of the airport for a five-story, 5,400-vehicle consolidated rental car facility. That facility will bring together the fleets of rental car companies located in Sea-Tac’s airport garage and in remote locations into a central terminal.

The port is buying a fleet of low-emission buses to shuttle passengers from the airport to the rental car terminal. The relocation of rental fleets will free up hundreds of parking spots for traveler parking. The terminal is expected to open in May 2011. The budget for the project is $412 million. Initial bids suggest that the project may come in below budget, Cooper said.

Sound Transit station: Sound Transit’s light-rail line from the airport to downtown Seattle is expected to open in late 2009. The transit agency is already testing trains on the elevated line that borders Highway 518 to the Tukwila station, which is already complete. Construction crews are still working on the extension from there to the airport. The station will be located on the northeast corner of the airport parking garage. Eventually, the airport line is expected to extend southward toward Tacoma.

Preconditioned air for planes waiting at gates: This $31 million project will enhance the airport’s heating and cooling capacity to serve aircraft waiting at the gates. It will allow aircraft to shut down their auxiliary power systems that provide heating and cooling to the interiors of the planes while the aircraft are boarding or unloading. Ground crews will connect the plane’s heating and cooling systems to the airport’s, cutting fuel consumption by some 5 million gallons per year.

Avian radar system: A new system will allow airport controllers to see flocks of birds nearing the runways and to halt takeoffs and landings while the birds are in the area. The airport is installing new software that is expected to improve the acuity of those systems.

Shuttle bus consolidation: Airport managers are working with local hotels to consolidate their shuttle services into a single system serving multiple hotels. That system would reduce congestion and pollution on the airport drive and perhaps cut back on hotel expenses compared with the present system under which each hotel has its own shuttle van.

John Gillie: 253-597-8663

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