David Zipper
@davidzipper.bsky.social
Senior Fellow @ MIT Mobility Initiative & Contributing Writer @ Vox, focused on transport, cities and tech. Words in Atlantic, CityLab, WaPo, etc. https://linktr.ee/davidzipper
Newsletter, speaking and advisory work: http://davidzipper.com
Newsletter, speaking and advisory work: http://davidzipper.com
Pinned
David Zipper
@davidzipper.bsky.social
· Jul 15
Look Both Ways Podcast: Episode 1
YouTube video by Look Both Ways with David & Wes
www.youtube.com
A bit of news:
@wesmars.bsky.social & I are launching Look Both Ways, a new podcast where we’ll debate everything transportation – from street design to robotaxis to fare-free transit.
First episode will be recorded live on Thurs, July 17th at 6p ET.
Join us then (and subscribe) ⤵️
🧵
@wesmars.bsky.social & I are launching Look Both Ways, a new podcast where we’ll debate everything transportation – from street design to robotaxis to fare-free transit.
First episode will be recorded live on Thurs, July 17th at 6p ET.
Join us then (and subscribe) ⤵️
🧵
Get 'em while they're young
electric bubble car for kids drives them to places on its own and without adults on board
www.designboom.com
November 10, 2025 at 4:24 PM
Get 'em while they're young
New NBER research finds that in NYC alone, Uber and Lyft collect $300M annually by making it hard to comparison shop before booking a ride.
www.nber.org/papers/w34441
www.nber.org/papers/w34441
November 10, 2025 at 2:11 PM
New NBER research finds that in NYC alone, Uber and Lyft collect $300M annually by making it hard to comparison shop before booking a ride.
www.nber.org/papers/w34441
www.nber.org/papers/w34441
@bmj.com, a renowned health journal, slams car bloat:
"Cars are becoming steadily larger, [and] with this comes potential harms to health...Action is needed locally, nationally, and internationally to curb sales of new SUVs and to reduce their presence in urban areas."
www.bmj.com/content/391/...
"Cars are becoming steadily larger, [and] with this comes potential harms to health...Action is needed locally, nationally, and internationally to curb sales of new SUVs and to reduce their presence in urban areas."
www.bmj.com/content/391/...
November 8, 2025 at 1:09 PM
@bmj.com, a renowned health journal, slams car bloat:
"Cars are becoming steadily larger, [and] with this comes potential harms to health...Action is needed locally, nationally, and internationally to curb sales of new SUVs and to reduce their presence in urban areas."
www.bmj.com/content/391/...
"Cars are becoming steadily larger, [and] with this comes potential harms to health...Action is needed locally, nationally, and internationally to curb sales of new SUVs and to reduce their presence in urban areas."
www.bmj.com/content/391/...
Tariffs are bad, but I'd have more sympathy for US transit agencies if they weren't inflating the costs of new buses by customizing absolutely everything (and fighting against efforts to lower costs by standardizing designs).
North American bus manufacturers, transit associations brace for new 10% bus tariff
Without relief mechanisms, transit agencies could lose buying power and have to delay climate-driven purchases.
www.masstransitmag.com
November 7, 2025 at 5:08 PM
Tariffs are bad, but I'd have more sympathy for US transit agencies if they weren't inflating the costs of new buses by customizing absolutely everything (and fighting against efforts to lower costs by standardizing designs).
Reposted by David Zipper
Would also put failure to prioritize Northeast Corridor investments; implement any sort of national design guidelines/benchmarks for transit and commuter rail on this list; and dumping the electrification report on the way out the door instead of making it an actual priority.
Sorry, but a lack of support for autonomous vehicles is not among Sec Pete's biggest missed opportunities at USDOT.
For instance:
🔹 Failure to stop Tesla from lying about Autopilot, FSD, etc
🔹 Failure to curb car bloat
🔹 Continuing to spend fed $$ on highway expansions that won't fix congestion
For instance:
🔹 Failure to stop Tesla from lying about Autopilot, FSD, etc
🔹 Failure to curb car bloat
🔹 Continuing to spend fed $$ on highway expansions that won't fix congestion
Pete Buttigieg Admits Biden Administration Should've Done More To Grow Autonomous Vehicles — Says DOGE-Like Department 'Makes Tons Of Sense'
Biden-era Transportation Secretary Pete Buttigieg says that the Biden administration could've done more to drive growth in the adoption of autonomous vehicles in the U.S. Autonomous Driving Tech Is Sa...
finance.yahoo.com
November 7, 2025 at 2:07 PM
Would also put failure to prioritize Northeast Corridor investments; implement any sort of national design guidelines/benchmarks for transit and commuter rail on this list; and dumping the electrification report on the way out the door instead of making it an actual priority.
Sorry, but a lack of support for autonomous vehicles is not among Sec Pete's biggest missed opportunities at USDOT.
For instance:
🔹 Failure to stop Tesla from lying about Autopilot, FSD, etc
🔹 Failure to curb car bloat
🔹 Continuing to spend fed $$ on highway expansions that won't fix congestion
For instance:
🔹 Failure to stop Tesla from lying about Autopilot, FSD, etc
🔹 Failure to curb car bloat
🔹 Continuing to spend fed $$ on highway expansions that won't fix congestion
Pete Buttigieg Admits Biden Administration Should've Done More To Grow Autonomous Vehicles — Says DOGE-Like Department 'Makes Tons Of Sense'
Biden-era Transportation Secretary Pete Buttigieg says that the Biden administration could've done more to drive growth in the adoption of autonomous vehicles in the U.S. Autonomous Driving Tech Is Sa...
finance.yahoo.com
November 7, 2025 at 2:04 PM
Sorry, but a lack of support for autonomous vehicles is not among Sec Pete's biggest missed opportunities at USDOT.
For instance:
🔹 Failure to stop Tesla from lying about Autopilot, FSD, etc
🔹 Failure to curb car bloat
🔹 Continuing to spend fed $$ on highway expansions that won't fix congestion
For instance:
🔹 Failure to stop Tesla from lying about Autopilot, FSD, etc
🔹 Failure to curb car bloat
🔹 Continuing to spend fed $$ on highway expansions that won't fix congestion
Reposted by David Zipper
NEW: The End of the Line: the centrepiece of Saudi Arabia’s Neom gigaproject - a 500m tall, 170km long wall-like building intended ultimately to house 9 million people - can’t get out of the ground, say more than 20 former Neom architects, engineers and senior executives.
ig.ft.com/saudi-neom-l...
ig.ft.com/saudi-neom-l...
End of The Line: how Saudi Arabia’s Neom dream unravelled
Mohammed bin Salman’s utopian city was undone by the laws of physics and finance
ig.ft.com
November 6, 2025 at 6:56 AM
NEW: The End of the Line: the centrepiece of Saudi Arabia’s Neom gigaproject - a 500m tall, 170km long wall-like building intended ultimately to house 9 million people - can’t get out of the ground, say more than 20 former Neom architects, engineers and senior executives.
ig.ft.com/saudi-neom-l...
ig.ft.com/saudi-neom-l...
“Unlike the car, the e-cargo bike afforded a unique sensitivity to the natural world and local environment [that] enabled parents to train their children in local geography and responsible mobility.”
www.tandfonline.com/eprint/RW2MT...
www.tandfonline.com/eprint/RW2MT...
November 4, 2025 at 10:58 PM
“Unlike the car, the e-cargo bike afforded a unique sensitivity to the natural world and local environment [that] enabled parents to train their children in local geography and responsible mobility.”
www.tandfonline.com/eprint/RW2MT...
www.tandfonline.com/eprint/RW2MT...
“The higher the exposure to PM2.5, the greater the extent of Alzheimer’s disease."
What the Air You Breathe May Be Doing to Your Brain
www.nytimes.com
November 4, 2025 at 1:58 PM
“The higher the exposure to PM2.5, the greater the extent of Alzheimer’s disease."
I respectfully disagree with Yonah here.
Reducing driving is a more important transportation goal than increasing transit ridership (for emissions, street space reallocation, etc).
Studies consistently show that eliminating fares doesn’t affect car use.
Reducing driving is a more important transportation goal than increasing transit ridership (for emissions, street space reallocation, etc).
Studies consistently show that eliminating fares doesn’t affect car use.
Alexandria & Richmond, Virginia have both implemented free bus service, as Mamdani has proposed.
They have also succeeded in increasing ridership—as of latest data, their ridership in 2025 is 31% & 25% higher than in 2019, respectively.
Overall US transit ridership is 20% lower in 2025 than 2019.
They have also succeeded in increasing ridership—as of latest data, their ridership in 2025 is 31% & 25% higher than in 2019, respectively.
Overall US transit ridership is 20% lower in 2025 than 2019.
Abigail Spanberger takes a swipe at Mamdani, saying "maybe he should be a Democrat" and that his campaign promises are dishonest.
November 3, 2025 at 8:10 PM
I respectfully disagree with Yonah here.
Reducing driving is a more important transportation goal than increasing transit ridership (for emissions, street space reallocation, etc).
Studies consistently show that eliminating fares doesn’t affect car use.
Reducing driving is a more important transportation goal than increasing transit ridership (for emissions, street space reallocation, etc).
Studies consistently show that eliminating fares doesn’t affect car use.
Is Barcelona the most bike-friendly city on the Mediterranean?
Nowhere else I’ve been comes even close.
Nowhere else I’ve been comes even close.
November 2, 2025 at 12:50 PM
Is Barcelona the most bike-friendly city on the Mediterranean?
Nowhere else I’ve been comes even close.
Nowhere else I’ve been comes even close.
Reposted by David Zipper
Portland's ruling class has a bizarre theory that the way to revitalize troubled locations is to remove seating, bathrooms, and open spaces, then add boulders and hideous fencing. You see it at Central Library, Firefighter Memorial, etc.
Meanwhile in Europe...
Meanwhile in Europe...
I just arrived in Barcelona. One of the first things I noticed (and love): So many public places to sit down!
Such a contrast with the hostile architecture that's widespread in US cities.
Such a contrast with the hostile architecture that's widespread in US cities.
November 1, 2025 at 7:13 PM
Portland's ruling class has a bizarre theory that the way to revitalize troubled locations is to remove seating, bathrooms, and open spaces, then add boulders and hideous fencing. You see it at Central Library, Firefighter Memorial, etc.
Meanwhile in Europe...
Meanwhile in Europe...
I just arrived in Barcelona. One of the first things I noticed (and love): So many public places to sit down!
Such a contrast with the hostile architecture that's widespread in US cities.
Such a contrast with the hostile architecture that's widespread in US cities.
November 1, 2025 at 5:23 PM
I just arrived in Barcelona. One of the first things I noticed (and love): So many public places to sit down!
Such a contrast with the hostile architecture that's widespread in US cities.
Such a contrast with the hostile architecture that's widespread in US cities.
Just left a meeting at Prague’s city hall, where this plaza out front was a parking lot until a few years ago.
October 31, 2025 at 3:30 PM
Just left a meeting at Prague’s city hall, where this plaza out front was a parking lot until a few years ago.
This chart is popular, but it’s misleading.
Many, many more children walk on Halloween compared to other dates. In fact, a child walking on Oct 31 is likely *safer* than they would be doing so on any other day.
Many, many more children walk on Halloween compared to other dates. In fact, a child walking on Oct 31 is likely *safer* than they would be doing so on any other day.
once again posting The Chart
October 31, 2025 at 2:44 PM
This chart is popular, but it’s misleading.
Many, many more children walk on Halloween compared to other dates. In fact, a child walking on Oct 31 is likely *safer* than they would be doing so on any other day.
Many, many more children walk on Halloween compared to other dates. In fact, a child walking on Oct 31 is likely *safer* than they would be doing so on any other day.
Data is sparse, but I'd bet school crossing guards are much more likely to die at work than police officers. They're at least as deserving of hazard pay.
Crossing guards face life-threatening dangers on the job
An investigation by The Associated Press and Cox Media Group Television Stations found that school crossing guards face dangerous conditions, with many injured or killed on the job.
apnews.com
October 31, 2025 at 10:06 AM
Data is sparse, but I'd bet school crossing guards are much more likely to die at work than police officers. They're at least as deserving of hazard pay.
The iconic front page, published 50 years ago today.
I found a copy on eBay 15 years ago. It now hangs above my desk.
I found a copy on eBay 15 years ago. It now hangs above my desk.
October 30, 2025 at 1:13 PM
The iconic front page, published 50 years ago today.
I found a copy on eBay 15 years ago. It now hangs above my desk.
I found a copy on eBay 15 years ago. It now hangs above my desk.
Reposted by David Zipper
A listener asks: "How can a young [transportation] engineer speak out about unsafe or outdated practices without risking their career?"
Cohost @wesmars.bsky.social -- a licensed engineer -- responds.
Cohost @wesmars.bsky.social -- a licensed engineer -- responds.
October 29, 2025 at 5:53 PM
A listener asks: "How can a young [transportation] engineer speak out about unsafe or outdated practices without risking their career?"
Cohost @wesmars.bsky.social -- a licensed engineer -- responds.
Cohost @wesmars.bsky.social -- a licensed engineer -- responds.
Reposted by David Zipper
@davidzipper.bsky.social on the societal backlash against cars:
"There's definitely more of an anti-car narrative than there was 10, 20, 50 years ago ... Even when you think about what happened after Ralph Nader wrote Unsafe At Any Speed in the 60s, the push was for safer cars, not fewer cars."
"There's definitely more of an anti-car narrative than there was 10, 20, 50 years ago ... Even when you think about what happened after Ralph Nader wrote Unsafe At Any Speed in the 60s, the push was for safer cars, not fewer cars."
October 29, 2025 at 4:13 PM
@davidzipper.bsky.social on the societal backlash against cars:
"There's definitely more of an anti-car narrative than there was 10, 20, 50 years ago ... Even when you think about what happened after Ralph Nader wrote Unsafe At Any Speed in the 60s, the push was for safer cars, not fewer cars."
"There's definitely more of an anti-car narrative than there was 10, 20, 50 years ago ... Even when you think about what happened after Ralph Nader wrote Unsafe At Any Speed in the 60s, the push was for safer cars, not fewer cars."
If Elon Musk wasn't so politically polarizing, "[American ]Tesla sales between October 2022 and April 2025 would have been 67-83% higher."
www.nber.org/papers/w34413
www.nber.org/papers/w34413
October 29, 2025 at 10:27 AM
If Elon Musk wasn't so politically polarizing, "[American ]Tesla sales between October 2022 and April 2025 would have been 67-83% higher."
www.nber.org/papers/w34413
www.nber.org/papers/w34413
Trump wants to force East Asia and Europe to buy Detroit's goliaths like the F-150. Not gonna happen.
Convincing explainer from @mikesmitka.bsky.social:
smitka.substack.com/p/pickups-fo...
Convincing explainer from @mikesmitka.bsky.social:
smitka.substack.com/p/pickups-fo...
October 28, 2025 at 8:53 PM
Trump wants to force East Asia and Europe to buy Detroit's goliaths like the F-150. Not gonna happen.
Convincing explainer from @mikesmitka.bsky.social:
smitka.substack.com/p/pickups-fo...
Convincing explainer from @mikesmitka.bsky.social:
smitka.substack.com/p/pickups-fo...
Excellent explanation of the holes in Mamdani's "fast and free" pledge for NYC buses:
"It certainly helps to speed up the process of boarding riders. But that’s not the thing that helps the most [to quicken trips]. And there are other ways to get those same savings while still collecting fares."
"It certainly helps to speed up the process of boarding riders. But that’s not the thing that helps the most [to quicken trips]. And there are other ways to get those same savings while still collecting fares."
Can Faster Buses Really Be Free?
www.nytimes.com
October 28, 2025 at 6:34 PM
Excellent explanation of the holes in Mamdani's "fast and free" pledge for NYC buses:
"It certainly helps to speed up the process of boarding riders. But that’s not the thing that helps the most [to quicken trips]. And there are other ways to get those same savings while still collecting fares."
"It certainly helps to speed up the process of boarding riders. But that’s not the thing that helps the most [to quicken trips]. And there are other ways to get those same savings while still collecting fares."
"In a small city northwest of Detroit, golf carts are replacing cars as the vehicle of choice."
More of this, please.
More of this, please.
Why a Michigan town is regulating its golf cart boom
YouTube video by CBS Evening News
www.youtube.com
October 27, 2025 at 4:56 PM
"In a small city northwest of Detroit, golf carts are replacing cars as the vehicle of choice."
More of this, please.
More of this, please.
Just had an espresso pod explode on my shirt two minutes before giving a keynote.
Silver lining: I felt wider awake than I would after a triple shot.
Silver lining: I felt wider awake than I would after a triple shot.
October 27, 2025 at 2:29 PM
Just had an espresso pod explode on my shirt two minutes before giving a keynote.
Silver lining: I felt wider awake than I would after a triple shot.
Silver lining: I felt wider awake than I would after a triple shot.