Funding must still be secured for design and construction of the I-84 viaduct project, which is expected to cost up to $5.3 billion. The state Department of Transportation is not expected to make a formal recommendation on the viaduct’s future until next year, although it is clearly moving in the direction of lowering the highway, sinking it below grade. An earlier option to lower and bury a majority of the viaduct in a tunnel has been eliminated as an option, its estimated price tag about $10 billion.
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