I do not see how incorporating mass transit is over design for something expected to last 100+ years. Especially for a region that has been adding tens of thousands of people per year for 10+ years, at an increasing pace.
Neither do I, however WSDOT has not released any details on the project but their renderings indicate they want to widen the freeway to some 10+ lane monstrosity[1]. Meanwhile Cascadia High Speed Rail has ideas about replacing the existing BNSF/Amtrak bridge with a double deck four track + four care lane bridge in addition to the I-5 bridge[2]. This combined makes a ridiculous amount of car lanes and railway tracks, plus a redundant bridge. There must be a better—and cheaper—way to cross this river.
