I-5 Lid Feasibility Study

What's Happening Now?

City Selects I-5 Lid Feasibility Study Consultant Team

We have selected a consultant team led by WSP, a global engineering firm with extensive local experience, for a feasibility study to explore opportunities for further lidding Interstate 5 between Denny Way and Madison Street in downtown Seattle. The WSP team also includes the local and national firms of Shiels Obletz Johnsen, OJB Landscape Architecture, Magnusson Klemencic Associates, BergerABAM, Rule Seven, Framework, HR&A Advisors and Enviroissues. Visit our blog for more information.

We are launching a study to explore the feasibility of building a new lid, or lids, across Interstate 5 in the core of Seattle's downtown, expanding from the existing lids of Freeway Park and the Washington State Convention Center. The study will investigate structural, urban design and financial solutions that would bridge the highway, support new uses, and reconnect neighborhoods that have been divided for over 50 years.

The study is being funded as part of the "community benefit agreement" related to the Washington State Convention Center's expansion. These funds were secured thanks to the hard work and passion of community members who have been exploring and advancing the Lid I-5 proposal. While this advocacy effort is separate from the feasibility study, the group's work will help inform the analysis and two of their members will be included on the study's Steering Committee along with other stakeholder group representatives. For more information on the Lid I-5 group and their work, visit their website.

A Request for Proposals (RFP) for consultant services was released in December 2018.

Watch our Director, Sam Assefa comment on Seattle's growth and the lid concept in this video produced by the Lid I-5 campaign.

I-5 Lid Feasibility Study Technical Team

The responsibility of the I-5 Lid Technical Team is to provide advice and subject matter expertise to the I-5 feasibility study.

Core Team Members:
David Driskell, OPCD
Lyle Bicknell, OPCD
Quanlin Hu, OPCD
Susan Mclaughlin, Seattle Dept. of Transportation
Rob Fellows, WA State Dept. of Transportation
Danielle Friedman, Dept. of Neighborhoods
David Graves, Seattle Parks Dept.
Rebecca Barnes, Independent Expert

Get Involved

Participate in giving us feedback!

The City is currently performing a Feasibility Study to determine whether building a lid over I-5 from Denny Way to Madison Street in Downtown is possible. Community feedback will help inform the analysis. All questions in this survey are optional and anonymous.

Translated versions:

I-5 Lid Feasibility Study Committee Meetings

Committee Work Session (December 11, 2019)

Preliminary Structural Feasibility Workshop (August 22, 2019)

Guiding Principals and Key Study Assumptions Workshop (June 11, 2019)

Orientation and Overview Meeting (March 26, 2019)


Consultant Work

Pre-Submittal Conference

Meeting at City Hall (December 20, 2018)

I-5 Lid Request for Proposals

University of Washington Student Studies