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        Voter approval (2016)
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        Planning, design and construction (2034-2045)
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        Open for service (2045)
 
On Aug. 5, 2021, the Sound Transit Board adopted a realigned capital plan to address steeply rising construction and real estate costs affecting many voter-approved regional transit expansion projects. Based on current revenue projections and cost estimates, the Board’s adopted plan identifies 2045 as the DuPont Sounder Extension opening date.