The Seattle Department of Transportation has released a third-party Magnolia Bridge Planning Study that considers three alternatives to replacing the 89-year-old structure, none of which SDOT can afford without state and federal aid.

The department will go over the results during a community engagement meeting set for 6-7:30 p.m. Thursday, June 6, at Catharine Blaine K-8, 2550 34th Ave. W.

The report by SCJ Alliance Consulting Services comes out amid a crowded race for Seattle City Council, with all District 7 candidates calling for an in-kind or 1:1 replacement of the Magnolia Bridge, which is estimated to cost $340 million to $420 million, the most expensive of the options assessed. 

But it’s also one of two options that “consistently performed best,” according to the report, the highest-ranking option being to construct an Armory Way Bridge into the east side of Magnolia — over the BNSF rail yard — and a new “West Uplands Perimeter Road to Smith Cove Park and the Elliott Bay Marina.

That option is estimated to cost $266 million in 2018 dollars, with the Armory Way Bridge component cost estimated at $45.4 million and a West Uplands Perimeter Road at $13.4 million. Demolishing the existing Magnolia Bridge is estimated to cost about $6.7 million.

But the report also found an in-kind replacement of the Magnolia Bridge scored almost 10 points higher than the Armory Way Bridge option when it came to “achieving public acceptance,” and also performed better in terms of mobility, access, construction duration and environmental impacts.

The Armory Way Bridge alternative would run from 15th Avenue West along West Armory Way, with northbound access from a new overpass (flyover) on 15th that would also accommodate light rail alignment, according to the report. Sound Transit has yet to identify its selected route for a Ballard light rail extension from downtown. The bridge would connect with Thorndyke Avenue West and 20th Avenue West in Magnolia, both of which would need to be improved.

The Washington National Guard is considering a move to North Bend, and an Interbay Public Development Committee is assessing the best use of the property, with one concept including high-rise housing and another for midrise. The Magnolia Bridge Planning Study does not address future use of the 25-acre site directly south of West Armory Way.

The Armory Way Bridge alternative also calls for retrofitting the eastern-most spur of the existing Magnolia Bridge with a ramp to Alaskan Way West, which would also need to be improved all the way to the Galer Street Flyover.

“The component analysis revealed that these components are required to provide an alternative access to Terminal 91, Port of Seattle property, and Expedia campus and distribute traffic between the existing Galer Street Flyover and this new Garfield Street Flyover,” the report states.

It appears there would need to also be support from the Port of Seattle to create the West Uplands Perimeter Road on its property — between 20th and 23rd avenues west — to continue providing access to Smith Cove Park and the Elliott Bay Marina. SDOT and the port already coordinate ongoing maintenance of Magnolia Bridge, which was damaged during the 2001 Nisqually earthquake.

This was the first of 10 bridge assessments funded by the Levy to Move Seattle, and will be followed by the launch of a Ballard Bridge Planning Study. The Legislature also approved funding for a Ballard-Interbay Regional Transportation System this session.