Sound Transit passes funding gap plan, prompting a sweeping overhaul of its ST3 expansion plan and delaying some projects while seeking new revenue sources. SEATTLE — Sound Transit’s governing board approved a sweeping overhaul of its voter-approved ST3 expansion plan Thursday, acknowledging a projected $34.5 billion funding gap that agency leaders say makes the original schedule unaffordable. The vote follows months of discussion over rising construction costs, inflation, lower-than-expected revenues and increasing operating expenses that have left the agency unable to fully fund the regional transit expansion package voters approved in 2016. This story continues below. An…