Seattle’s transit agency just drew a line between what it can build and what it can’t. The Sound Transit Board adopted an updated ST3 system plan on May 28 that fully funds construction of 13 projects while deferring 10 others, a direct response to an estimated $34.5 billion funding gap over the next 20 years. Construction Dive covered the vote, which sorts a sprawling capital program into tiers of affordability.
What the revised ST3 plan funds
The board’s fully funded list runs to 13 projects, and it includes the heavy hitters. The West Seattle Link extension stays in. So do phases 1 and 2 of the Everett Link extension, the Tacoma Dome Link extension, the Ballard Link initial segment to Seattle Center, and two new operations and maintenance facilities. Seven more projects get partial funding to carry them through planning and design. Five sit in a pursue-more-money bucket. Ten are deferred until new revenue shows up.
The pressure here is cost escalation, and it’s brutal. ST3’s total program estimate has climbed toward $185 billion in recent years, well above what voters approved when the measure passed. Board chair Dave Somers called the resolution both realism and optimism, which is a polite way of saying the agency ran out of room to pretend every project pencils out on the original timeline.
Why the deferral list matters for builders
A deferral isn’t a cancellation, but it reshapes the bid pipeline. Contractors planning around ST3 now have a clearer read on which packages carry real near-term funding and which are parked. That certainty has value, even when the news is a delay, because it lets firms aim estimating and labor at work that’s actually going to procurement.
The funding squeeze isn’t unique to Seattle. Transit megaprograms across the country are colliding with the same math, where ballooning costs meet flat or uncertain federal support. California’s high-speed rail program scaled its ambitions to a Central Valley operating segment for the same reason, and privately financed bets like Brightline West are partly a response to how hard public transit dollars have become to secure.
Sound Transit also told staff to do something useful: build an adaptive program management plan and a project delivery framework by the end of 2026. The goal is to find cost savings inside capital projects and keep the board ahead of risk rather than reacting to it. After years of estimates running away from the agency, that’s the more consequential move.
The honest read is that ST3 is now a program managed by triage. Thirteen projects move. Ten wait. The voter-approved vision survives on paper, but its delivery depends on revenue the agency doesn’t yet have, and on a discipline it’s only now putting in place.
Source: Sebastian Obando, Construction Dive, June 2, 2026.