Visions for Lidding I-5 in Downtown Seattle

The notion of fully capping I-5 as it runs through central Seattle has been gaining steam. The city could stand to gain hundreds of acres of urban land.

1 minute read

October 10, 2018, 2:00 PM PDT

By Philip Rojc @PhilipRojc


Seattle, I-5

SounderBruce / Flickr

An ambitious idea is gaining traction in Seattle, following in the footsteps of the city's waterfront remake. With the Lid I-5 campaign in the lead, advocates are exploring what it would take to fully lid I-5. "During construction in the early to mid 1960s," Knute Berger writes, "it had destroyed some 6,000 homes, slashed through the International District as it cut a concrete canyon through the heart of the city."

But times have changed. Recently, "a city grant has helped come up with concepts for how the new 'land' of a lid — a concrete cover to I-5 strong enough to hold buildings, parks, roads and people — could be used."

I-5 is already partially lidded in several places, like Freeway Park and the Washington State Convention Center. "As part of the package to expand the Washington State Convention Center, $1.5 million has been allocated to the city for an upcoming study of the feasibility of lidding which will be undertaken in 2019."

The project is bound to be expensive, complex, and will likely take many years to complete. But given downtown land prices, Berger writes, much of the cost "could well pencil out." In the meantime, the idea has sparked lively discussion about what might be done with all that new land, and a more cohesive downtown.

See also: A Closer Look at the Ambitious Plans to Cap I-5 in Downtown Seattle

Monday, October 8, 2018 in Crosscut

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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