urban interchange with I-705 opened on January 22, 1997. The project cost a total of $165.3 million to construct, with the majority of funds from the federal government and a land claims settlement with the Puyallup Tribe. The Blair Bridge was closed and demolished to make way for a wider channel on the Blair Waterway for larger container ships. As part of the Puget Sound Gateway Program approved in 2015, WSDOT plans to build a freeway extension of SR 509 around the south side of Seattle–Tacoma International Airport and a spur freeway near the Port of Tacoma. The projects, together with an extension of State Route 167, are anticipated to cost $2 billion and were proposed in the mid-20th century. The extension near SeaTac and a new interchange with I-5 began construction in November 2021 and is scheduled to be completed by 2028 in three stages. The first major stage, construction of the I-5 interchange and SR 99 overpass, is scheduled to be completed in 2025. The Port of Tacoma project would also open in 2028, constructing a new diverging diamond interchange with I-5 near Fife for the extended SR 167 and a short freeway designated as SR 509 Spur. The SR 509 expansion was initially planned in the early 1990s and had funding approved by the legislature in 1998, but it was cancelled by later ballot measures. Major intersections References External links Highways of Washington State 509 Transportation in Pierce County, Washington Transportation in King County, Washington