The board of Seattle’s Sound Transit announced on 23 July that it had identified a preferred option to extend the city’s light rail line south from SeaTac to Federal Way – alongside the western side of the I-5 motorway instead of over Highway 99. There would be intermediate stops at Kent/Des Moines and South 272nd Street.
The unanimous vote gives the I-5 alignment preferred status in the final environmental impact studies and detailed design work will now be undertaken, including examination of opportunities for future transit-oriented development in the Midway area, before a final board vote in November 2016.
Estimated at USD1.4bn, the I-5 route could save USD300m in construction and land acquisition costs and is backed by the four suburban cities along the route to minimise construction impacts on businesses and residents.
Pending approval, final design would begin in 2017 and construction in 2019, for opening to Kent/Des Moines in 2023.