Alaskan Way Viaduct: Complicated, visionary — a deep tunnel could work

FOR too long, our region has been high-centered on the vexing question of how best to replace the Alaskan Way Viaduct. A complicated yet visionary plan featuring a deep-bored tunnel has emerged and deserves a healthy chance to succeed.

After years of debate among citizens and elected leaders, most participants in numerous discussions agreed on an expensive but attractive idea. The latest plan calls for building a deep tunnel, tearing down the viaduct, creating a new street underneath the viaduct, and developing a new parklike promenade along the waterfront — in that order.

Exhaustive public process that produced the plan demands that even longtime tunnel naysayers, such as this editorial page, give this serious proposal a serious look.

In dramatic contrast to the earlier tunnel plan, sequencing of events requires much less down time for waterfront businesses and streets, with obvious deleterious spillover onto Interstate 5. The old plan would have resulted in perhaps six years of disruption; this approach involves less severe interruption for about half that time.

This is key: The viaduct doesn't come down until the tunnel is finished.

We've seen what long construction projects can do to a neighborhood. They can kill business and stymie mobility.

The cost of the project is pegged at $4.25 billion, with most of the total the state share, $2.8 billion already in hand, and the local portion coming from specified new tax sources.

No need to be naive. The cost is a guesstimate; the final number will be higher.

Very importantly, increased costs to local residents will be high but borne over many years. The sincere hope is that the economy will improve.

The current recession is one factor that helps make this project more attractive. The convergence of a jobs package and economic stimulus combined with the longtime vision of connecting the city to the waterfront gives this package momentum.

Another factor is that all those supporters of a so-called surface-transit option had to realize that the capacity needs of their favorite solution could never be met. The line of red lights would have choked the streets with traffic.

Deep-tunnel costs are the major concern. But this is a 50-year decision that affects the look and feel of one of the prettiest cities in America.

The viaduct has to come down because it is dangerous and could tumble in an earthquake. At some point, the dithering has to end. The region has to do something.