The never-before-used design is already being built.

Sound Transit is installing train tracks on the Interstate 90 bridge that, when complete, will be the first floating bridge to carry a train. "The water level below the Interstate 90 bridge typically fluctuates 2 feet annually, as spring runoff enters Lake Washington and the Army Corps of Engineers maintains boat passage at the Ballard Locks," Mike Lindblom reports for the Seattle Times. To further complicate this engineering challenge, train tracks must remain parallel or trains will derail.
The weight of the train means the transit provider must take measures to ensure the bridge’s buoyancy. One change that I-90 drivers can see from their car windows has to do with highway barriers. "Contractors are instead replacing concrete barriers, which wouldn’t stop a train anyway, with cable fence to prevent falls into the lake," Lindblom reports.
This bridge is a component of the Sound Transit's East Link light rail extension. Sound Transit says the train will take passengers from Bellevue to Seattle and the ride would take 20 minutes. "The 14-mile extension remains on schedule to open in mid-2023, followed by two stations in Redmond by 2024, serving an estimated 50,000 passengers per day," Lindblom writes.
FULL STORY: Train tracks on the I-90 floating bridge? Sound Transit is building them now.

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

Congressman Proposes Bill to Rename DC Metro “Trump Train”
The Make Autorail Great Again Act would withhold federal funding to the system until the Washington Metropolitan Area Transit Authority (WMATA), rebrands as the Washington Metropolitan Authority for Greater Access (WMAGA).

DARTSpace Platform Streamlines Dallas TOD Application Process
The Dallas transit agency hopes a shorter permitting timeline will boost transit-oriented development around rail stations.

Parks: Essential Community Infrastructure — and a Smart Investment
Even during times of budget constraint, continued investment in parks is critical, as they provide proven benefits to public health, safety, climate resilience, and community well-being — particularly for under-resourced communities.

Porches, Pets, and the People We Grow Old With
Neighborhood connections and animal companions matter to aging with dignity, and how we build can support them. Here’s a human-scale proposal for aging in place.

Single-Stair Design Contest Envisions Human-Scale Buildings
Single-stair building construction is having a resurgence in the United States, where, for the last several decades, zoning codes have required more than one staircase in multi-story housing developments.
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.
City of Charlotte
Municipality of Princeton
City of Camden Redevelopment Agency
City of Astoria
Transportation Research & Education Center (TREC) at Portland State University
US High Speed Rail Association
City of Camden Redevelopment Agency
Municipality of Princeton (NJ)