Traffic Travis | WSDOT: Expect Heavy Congestion Thursday Night

Commuters were warned Thursday to expect heavy congestion on the drive home as demolition of the Alaskan Way Viaduct continued for a sixth day.

"We typically see Thursdays and Fridays as being some of the heaviest," state Transportation Department spokesman Travis Phelps said. "The last three days, we've noticed a strand of increasing congestion in the afternoons."

Wednesday's evening commute was the worst of the week so far, Phelps said. Travelers on Interstate 5 hit bumper-to-bumper delays of up to one hour between Seattle and Shoreline. Traffic also backed up on First and Fourth Avenues South as drivers tried to navigate the city street grid.

Morning commutes have been a different story, Phelps said, with traffic flowing close to normal. WSDOT attributes that to people who are leaving home earlier or later, in addition to people who switched to transit or water taxi during the closure.

The Seattle Department of Transportation reports the morning commute peak ramped up and hour earlier this week at 6: 30 a.m. It also tapered off earlier at 8 a.m.

"The evening commutes have been challenging as well; again, starting earlier (before or around 4 p.m.) and lasting a bit longer than usual (after 6:30 p.m.)," SDOT reports .

But the evening commute is tougher to manage because the corridor headed out of downtown is narrower and more hampered by train crossings, transportation officials say. There also is likely to be more people leaving the office at once, and not as much staggered commuting as during the morning.

The viaduct carries 110,000 vehicles per day. It was closed last Friday for a nine-day stretch so crews can demolish the southernmost mile and make room for a new highway that will eventually connect to a deep-bore tunnel under downtown.

Crews remain on schedule to reopen the viaduct by early Monday, Phelps said. By then, the northern half of the viaduct will be connected with a new highway just west of the existing viaduct in Sodo. The speed limit will be reduced to 40 mph.

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