Its design can appear baffling at first, but the DDI presents drivers with far fewer opportunities to collide with each other than traditional four-way intersections.

Laura Bliss covers the spread of the diverging diamond interchange, or DDI. "Rather [than] make drivers turn at a right angle to merge onto a highway, the two directions of traffic diverge and ribbon over one another. One lane peels off to funnel cars onto the highway, and they never have to turn against traffic."
Bliss includes an embedded Youtube video from the city of Calgary, which cheerily explains how drivers should use a DDI.
"DDIs are proliferating because they're safer than a traditional four-way intersection. Where two, two-lane roadways intersect, drivers have 32 separate opportunities to collide into each other. In a DDI, there are only 14." They can also incorporate pedestrian crossings, as the Calgary video shows.
FULL STORY: The Diverging Diamond Interchange Is Coming to a Road Near You

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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