Four years later, there are a host of unanswered questions about the events of 9/11, including the unexplained and unprecedented architectural collapses of three office towers, and the extent of toxicity in the air of Lower Manhattan.
"Why Did WTC 7 Fall? [WTC 7]was...probably the first steel skyscraper anywhere to collapse solely because of fire. We still don't know why...according to FEMA's report on the collapse [the fire hypothesis] "has only a low probability of occurrence."
"How did the twin towers fall? Many FDNY personnel who saw the south tower collapse reported explosions at the lower levels as the top began collapsing. These reports, as well as "squibs" of smoke seen on video of the collapses, have led to theories that the towers were brought down in controlled explosions."
"Conspiracy theorists aren't the only ones who dispute [the official]version: Some fire scientists also take issue with [it]...And the point isn't just historical. The lessons learned from the WTC collapse will inform decisions about the safety of other modern office towers."
FULL STORY: Open and Shut
Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.
Chicago’s Ghost Rails
Just beneath the surface of the modern city lie the remnants of its expansive early 20th-century streetcar system.
Amtrak Cutting Jobs, Funding to High-Speed Rail
The agency plans to cut 10 percent of its workforce and has confirmed it will not fund new high-speed rail projects.
Ohio Forces Data Centers to Prepay for Power
Utilities are calling on states to hold data center operators responsible for new energy demands to prevent leaving consumers on the hook for their bills.
MARTA CEO Steps Down Amid Citizenship Concerns
MARTA’s board announced Thursday that its chief, who is from Canada, is resigning due to questions about his immigration status.
Silicon Valley ‘Bike Superhighway’ Awarded $14M State Grant
A Caltrans grant brings the 10-mile Central Bikeway project connecting Santa Clara and East San Jose closer to fruition.
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.
Caltrans
City of Fort Worth
Mpact (founded as Rail~Volution)
City of Camden Redevelopment Agency
City of Astoria
City of Portland
City of Laramie