THE Port of Seattle has unveiled plans to spend US$9.5 billion on making capital improvements at the Seattle-Tacoma international Airport and its marine terminal facilities over the coming decade. The ambitious plan could include the development of a second, parallel airport. "This is a testament to the growth of the region," port of Seattle managing director of economic development David McFadden said. He will be one of the panelists at a Seattle Construction & Development event on March 31, reported Seattle's Bisnow. Seattle's population grew by 136,000 people since 2010, a 22 per cent increase in a decade. The city's population hit 745,000 in 2018, according to The Seattle Times. While the city of Seattle swells, the population of the Puget Sound region does as well. It is currently adding 188 people a day, which equates to 500,000 new residents since 2010. "These improvements provide the region the capacity to grow and perform economically and support a tremendous amount of commerce," Mr McFadden said. The Port of Seattle is the parent organisation of the Northwest Seaport Alliance, which is composed of both the Seattle and Tacoma ports. Combined, the port authority is the third-largest cargo port in the United States by container volume. If all goes to plan, the improvements will include $200 million for a new cruise berth, $39 million for development of terminal 91, $35 million for berth replacement at terminal 91, $30 million to bring electrical power to the waterfront, $23 million for Fisherman's Terminal Gateway Building, $17 million for a terminal 117 habitat restoration programme, and $10.5 million for a maritime innovation centre. The port is also looking for sites to build another airport. Fifty million people use the airport every year and it will eventually run out of capacity, Mr McFadden said.