This 4-page summary report (PDF) is a summary of a technical paper attempting to show differences in the reduction in road crashes that result from road diets.
From the study: "A road diet involves narrowing or eliminating travel lanes on a roadway to make more room for pedestrians and bicyclists. (They) are often conversions of four-lane, undivided roads into three lanes-two through lanes plus a center turn lane."
The study was conducted in California, Washington and Iowa:
"The Iowa data indicate a 47 percent reduction in total crashes while the HSIS (California and Washington) data indicate a 19 percent decrease-a substantial difference."
It's clear from the results that road diets do reduce crashes - the only issue appears to be just how great a reduction.
Thanks to Transportation Research E-Newsletter
FULL STORY: Evaluation of Lane Reduction "Road Diet" Measures on Crashes

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Trump deemed the landmark civil rights agreement “illegal DEI and environmental justice policy.”

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

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Report: Zoning Reforms Should Complement Nashville’s Ambitious Transit Plan
Without reform, restrictive zoning codes will limit the impact of the city’s planned transit expansion and could exclude some of the residents who depend on transit the most.

Judge Orders Release of Frozen IRA, IIJA Funding
The decision is a victory for environmental groups who charged that freezing funds for critical infrastructure and disaster response programs caused “real and irreparable harm” to communities.
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