Early reminder – a two-part closure will affect Alaskan Way Viaduct drivers this weekend. Northbound, it’ll be closed 5:30-8:30 pm Saturday night for the Seafair Torchlight Run; southbound, it’ll be closed for ongoing construction from just before midnight Saturday night, till early Monday. Read on for more details:

A full slate of weekend activities, including closures in both directions of the State Route 99 Alaskan Way Viaduct, could mean delays for drivers heading into downtown Seattle. The Washington State Department of Transportation (WSDOT) urges drivers to map out routes in advance, allow extra time and prepare for more congestion than usual.

Northbound SR 99:

· Preparations for the Seafair Torchlight Run will close northbound SR 99 between the West Seattle Bridge and the Battery Street Tunnel for several hours starting at 5:30 p.m. Saturday, July 30. The northbound lanes are expected to reopen by 8:30 p.m. Saturday.

Southbound SR 99:

· WSDOT crews will close southbound SR 99 from the Battery Street Tunnel to the West Seattle Bridge from 11:59 p.m. Saturday, July 30, to 5 a.m. Monday, Aug. 1, to install a new stormwater drainage system at the south end of the viaduct.

The drainage work is part of construction under way to replace the south end of the Alaskan Way Viaduct with a side-by-side elevated highway. Skanska, WSDOT’s contractor, is on track to complete the southbound lanes of the new SR 99 roadway and start demolishing the southern mile of the viaduct this October.

Downtown Seattle Events:

· The Seattle Mariners have three home games this weekend: 7:10 p.m. Friday, July 29, 1:10 p.m. Saturday, July 30, and 1:10 p.m. Sunday, July 31.

· The Seafair Torchlight Run officially begins at 6:30 p.m. on Saturday, July, 30. The route includes parts of the Alaskan Way Viaduct and several downtown streets.

· The Seafair Torchlight Parade begins at 7:30 p.m. on Saturday, July, 30. The route includes several downtown streets.

Coming soon: Nine-day closure of the viaduct

This weekend’s closure to install a stormwater drainage system is part of the work crews must complete to prepare for an extended closure of the viaduct in late October. Northbound SR 99 will close from Spokane Street to South Royal Brougham Way and southbound SR 99 will close from the Battery Street Tunnel to the West Seattle Bridge for up to nine days while crews:

· Demolish approximately 300 yards of the viaduct near South Royal Brougham Way.

· Complete a four-lane construction bypass to connect the central waterfront section of the viaduct to the north end of the new southbound roadway.

· Connect SR 99 lanes south of South Holgate Street to the south end of the new roadway bridge.

· Complete construction of a new southbound off-ramp to South Atlantic Street. The existing ramp to South Royal Brougham Way will close.

When SR 99 reopens, both directions of traffic will be shifted onto the new southbound SR 99 bridge – two lanes in each direction – and crews will begin construction on the new northbound roadway in the footprint of the demolished viaduct. A step-by-step simulation showing how construction will unfold is available at wsdot.wa.gov/projects/viaduct/simulations.