No fewer than seven transportation disruptions in Seattle make this a great weekend to explore your own neighborhood.

Some closures conflict with Mariners baseball traffic Friday and Saturday nights and Sunday afternoon, as well as Sounders soccer Saturday afternoon. But the Huskies and Seahawks football teams, which draw larger crowds, are out of town, and dry weekends to pour concrete won’t last forever.

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Montlake Bridge will close all weekend, from 10 p.m. Friday until 5 a.m. Monday, while contractors replace mechanical drawspan parts. A sidewalk will remain available for walking and bicycling. Buses will detour via University Bridge, a slower route that Seattle Department of Transportation eased somewhat by striping a red bus lane on Northeast Campus Parkway westbound.

The southbound I-5 mainline through Sodo will close again after an eight-week reprieve, from I-90 to the Spokane Street exit, at 10 p.m. Friday until 5 a.m. Monday, as workers begin to install new expansion joints between freeway decks.

Southbound traffic will be funneled through downtown Seattle via collector-distributor lanes, off to the right, then reenter the mainline’s right edge. Downtown exits remain open. After the sporting events, the onramp from I-90 (near Edgar Martinez Drive) to southbound I-5 will be temporarily open.


Meanwhile, the I-5 express lanes will close from 9 p.m. Friday until 5 a.m. Monday to replace 26 broken concrete panels between Yesler Way and Northgate, said spokesperson Tom Pearce of the Washington State Department of Transportation.

That timing fits with the fact express lanes can’t be used southbound anyway, because of the Sodo closures. But northbound drivers also lose capacity.

“There’s never a really good weekend to do these projects, but we need to get them done,” Pearce said.

The Highway 99 tunnel will close both directions from 10 p.m. Friday until 6 a.m. Saturday for maintenance.

Considering transit? Sound Transit light rail will be cut off between Rainier Beach and Tukwila International Boulevard stations all day Sunday for track replacement. Train riders passing through, including people heading to and from Seattle-Tacoma International Airport, must switch to shuttle buses, going every 10 minutes through the closed area.

Why not continue the shuttles all the way to the airport? Pierce Transit, which provides the shuttle buses, is short of transit operators, said Sound Transit spokesperson John Gallagher. To assure frequent trips, they’ll turn back at Tukwila rather than travel 4 more miles to complete the round-trip to Sea-Tac.


Washington State Ferries continues to operate only one boat, the M/V Chimacum, on the Bremerton-Seattle route because the M/V Kaleetan needs repairs. Crew and boat shortages reduced the Coupeville-Port Townsend route to one ferry, while service on the Fauntleroy-Vashon-Southworth triangle is reduced to two boats on Sundays.

Finally, West Marginal Way Southwest drivers, already detoured from the cracked West Seattle highrise bridge, could face slowdowns when city crews trim trees near the Duwamish Longhouse, and install vehicle-detection signals in the huge Highland Park Way Southwest crossroads. Watch for lane reductions from 3 a.m. to 1 p.m. both Saturday and Sunday.

WSDOT will close southbound I-5 lanes in Sodo again the next two weekends.

The state’s roadwork has created surface gaps where new concrete is higher than the expansion joints, now marked with orange “BUMP” signs.

Engineers are looking for ways to soften the jolt, Pearce said Thursday. Contractors paved the whole 1¼ miles this summer to save money, rather than alternate between expansion joint and pavement teams.

The left side of a half-dozen joints will be installed this weekend, he said. But a total 40 expansion joints need fixing so I-5 won’t become entirely smooth until 2022.