Research suggests that the Trip Generation Manual—a familiar tool for planners calculating the vehicle trips expected to be generated by developments of various sizes and uses—produces "phantom trips" and unneeded automobile infrastructure.
Eric Jaffe suggests that it might time to add the Trip Generation Manual from the Institute for Transportation Engineers to the list of questionable planning tools. Jaffe cites research by Adam Millard-Bell of the University of California, Santa Cruz, "who challenges the merits of the Trip Generation Manual in an upcoming research paper [pdf] (nicely summarized in ACCESS magazine)." See the video below of Millard-Bell describing his research.
In the study, "Millard-Ball reports that the ITE manual may overestimate the number of trips generated from a new development by as much as 55 percent," according to Jaffe. The result of these "phantom trips": "cities may build way more roads than necessary, perpetuating sprawl and leaving less street space for non-drivers in the process."
FULL STORY: A Widely Used Planning Manual Tends to Recommend Building Far More Roads Than Necessary

Trump Administration Could Effectively End Housing Voucher Program
Federal officials are eyeing major cuts to the Section 8 program that helps millions of low-income households pay rent.

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

Ken Jennings Launches Transit Web Series
The Jeopardy champ wants you to ride public transit.

Driving Equity and Clean Air: California Invests in Greener School Transportation
California has awarded $500 million to fund 1,000 zero-emission school buses and chargers for educational agencies as part of its effort to reduce pollution, improve student health, and accelerate the transition to clean transportation.

Congress Moves to End Reconnecting Communities and Related Grants
The House Transportation and Infrastructure Committee moved to rescind funding for the Neighborhood Equity and Access program, which funds highway removals, freeway caps, transit projects, pedestrian infrastructure, and more.

From Throughway to Public Space: Taking Back the American Street
How the Covid-19 pandemic taught us new ways to reclaim city streets from cars.
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