Confronting a spaghetti bowl of roads in and out of SeaTac International Airport, south of Seattle, owner Sound Transit opted for its first-ever turnkey design-build contract to better integrate civil, structural, station and system components of a new light-rail system extension that will serve the airport.

“To get over that mess and allow for capacity for future roadway access to the airport—to avoid all of that—an elevated guideway was seen as being the best way to go,” says Miles Haupt, Sound Transit project director for the 1.6-mile South 200th Link Extension.