Viaduct demolition will last about 6 months, bringing disruption and noise
SEATTLE - The Alaskan Way Viaduct will shut down Jan. 11, marking the longest major highway closure ever in the Puget Sound region. The new State Route 99 tunnel will replace the viaduct sometime the week of Feb. 4 and is expected to be a safer option for commuters. But the transition will result in big traffic backups.