The first day of the Alaskan Way Viaduct closure triggered plenty of bottlenecks, but history says next week could be worse, the state warns.

Share story

Transportation officials are bracing for possibly tougher commutes next week, after Friday’s slow but predictable start of the prolonged Highway 99 closure.

People headed for work earlier than usual in the morning, and hit the highways sooner in the afternoon, leading to slow but mostly tolerable conditions.

“Monday’s going to be a slightly different animal from Friday, because we usually see more traffic on Monday mornings, compared to the typical ‘Friday lite,’ ” said Travis Phelps, spokesman for the Washington State Department of Transportation (WSDOT). “Drivers need to have their A game on for Monday.”

The shutdown from Belltown to the Spokane Street Viaduct is expected to last two weeks. It is meant as a precaution while tunnel-boring machine Bertha digs beneath the Alaskan Way Viaduct.

There were scattered reports of crowded trains and buses. West Seattle water taxi ridership tripled from normal levels. The 5:15 p.m. boat carried 236 people compared with 54 a week ago.

Traffic was stop-and-go all day Friday through Northgate into Seattle, the Renton S-curves, and downtown Bellevue. Afternoon traffic leaving downtown flowed easily, and Aurora Avenue North was lightly used.

But drivers tweeted that it took an hour to crisscross Seattle using Mercer Street or downtown in the afternoon. Some bus detours required nearly 50 minutes through West Seattle and Sodo.

Transportation consulting firm DKS Associates called the regional pattern “business as usual,” as of 4 p.m. The government performance so far is “awesome,” said principal Eric Shimizu. “I feel like they’re a lot more proactive, in cooperating with one another.”

Travelers benefited from no major crashes or agency foul-ups. (A garbage truck struck the Alaskan Way Viaduct just before 11:30 a.m., causing a natural-gas leak and temporary road closure, but there were no injuries or lasting effects on traffic.)

However, some less-than-convenient timing for a lane closure and re-stripe at Marysville, to make room for expansion-joint replacements, led to clogs on northbound I-5 from 128th Street Southwest to the Snohomish River. For the sake of safety, Phelps said, the job needs to be done soon, before heavier summer traffic shows up.

He suggested people follow the www.99closure.org website, and track news and transit feeds Monday morning — and be ready to change travel modes or times.