Putting a lid on the interstate through downtown Seattle could create new space for parks and housing, reduce pollution, and reconnect the disrupted street grid.

Doug Trumm reports on Seattle's "quiet" release of the Lid I-5 Feasibility Study, which highlights the benefits of capping freeways in cities. The report, funded through a community benefits package from the Washington State Convention Center expansion project, was "designed to understand the technical and financial feasibility of lidding the freeway and to look at opportunities for maximizing public benefits."
Trumm assesses the top takeaways from the study, which analyzed the potential impacts and effects of putting a "lid" on a 17-acre area of Interstate 5. According to the study, the lid could accommodate a 2.5-9.8 acre park, reconnect the street grid, reduce noise pollution, and improve stormwater drainage. The project would also create more space for housing construction in Seattle's dense downtown. "WSP did some structural engineering analysis to determine how much development could go atop the lid, and, while each section is different, the short answer is a lot. Bicknell’s 2019 article on earlier lid feasibility research had hinted midrise and some highrise development was possible. The final report estimated up to 4.7 million square feet of new housing is feasible–enough space for 4,500 homes–and between two and five million square feet of commercial/office space."
Lid I-5 Seattle's Scott Bonjukian told The Urbanist that "getting some more money for studies and planning in the next state transportation package is the next major goal."
FULL STORY: 8 Takeaways from Seattle’s Lid I-5 Feasibility Study

Eugene Ends Parking Minimums
In a move that complies with a state law aimed at reducing transportation emissions, Eugene amended its parking rules to eliminate minimum requirements and set maximum parking lot sizes.

How Paris, Texas Became a ‘Unicorn’ for Rural Transit
A robust coalition of advocates in the town of 25,000 brought together the funding and resources to launch a popular bus service that some residents see as a mobility lifeline—and a social club.

How ‘Daylighting’ Intersections Can Save Lives
Eliminating visual obstructions can make intersections safer for all users.

Brightline West Awarded $3 Billion in Federal Funding
The high-speed rail line will cut travel time between Southern California and Las Vegas roughly in half.

OKC Celebrates New Rapid Bus Line With Free Rides
The agency wants to showcase the benefits of a recently opened BRT line connecting the northwest part of the city to downtown.

Turning Out the Lights on Light Pollution
Limiting light pollution can have beneficial effects for humans, animals, and the local economy.
City of Kissimmee - Development Services
City of Kissimmee - Development Services
Alamo Area Metropolitan Planning Organization
HUD's Office of Policy Development and Research
HUD's Office of Policy Development and Research
Chaddick Institute at DePaul University
Park City Municipal Corporation
National Capital Planning Commission
City of Santa Fe, New Mexico
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