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) ⤵️
🧵
“Car bloat”—increasingly oversized automobiles—worsens road safety, affordability and the environment.
Here are some of the stories I wrote in 2025 examining the trend and proposing solutions. 🧵
In @vox.com, I likened car bloat to secondhand smoke (which helped bring down the US tobacco industry).
Here are some of the stories I wrote in 2025 examining the trend and proposing solutions. 🧵
In @vox.com, I likened car bloat to secondhand smoke (which helped bring down the US tobacco industry).
Gigantic SUVs are a public health threat. Why don’t we treat them like one?
The anti-tobacco playbook could help turn the US public against their beloved oversized cars.
www.vox.com
December 28, 2025 at 1:08 PM
“Car bloat”—increasingly oversized automobiles—worsens road safety, affordability and the environment.
Here are some of the stories I wrote in 2025 examining the trend and proposing solutions. 🧵
In @vox.com, I likened car bloat to secondhand smoke (which helped bring down the US tobacco industry).
Here are some of the stories I wrote in 2025 examining the trend and proposing solutions. 🧵
In @vox.com, I likened car bloat to secondhand smoke (which helped bring down the US tobacco industry).
Car bloat is becoming a global problem, not just an American one
SUVs and big Utes "are 44 per cent more likely to kill an adult pedestrian or cyclist in a crash compared with a sedan, and 82 per cent more likely to kill a child" www.theage.com.au/national/vic...
Pedestrian fatalities reach 17-year-high. This trend could be why
Fifty-one pedestrians had been killed on the state’s roads this year as of Saturday – the most in any calendar year since 2008.
www.theage.com.au
December 27, 2025 at 10:34 PM
Car bloat is becoming a global problem, not just an American one
Reposted by David Zipper
Reposted by David Zipper
I hate that we’re having to think in these terms, but the evidence seems to be bearing out that steep fare hikes are less damaging to ridership than service cuts.
2025 was brutal for US transit. Agencies faced budget deficits, flat ridership, and open hostility from the White House.
I wrote a series of stories outlining ways to help transit endure.
Lesson #1: Whatever you do, don’t cut service. Riders will leave – permanently.
Here are a few others 🧵
I wrote a series of stories outlining ways to help transit endure.
Lesson #1: Whatever you do, don’t cut service. Riders will leave – permanently.
Here are a few others 🧵
The Last Thing US Transit Agencies Should Do Now
Rising costs and widening deficits as pandemic aid runs out are challenging bus and train operators in many cities. But cutting service needs to be a last resort.
www.bloomberg.com
December 27, 2025 at 2:37 PM
I hate that we’re having to think in these terms, but the evidence seems to be bearing out that steep fare hikes are less damaging to ridership than service cuts.
2025 was brutal for US transit. Agencies faced budget deficits, flat ridership, and open hostility from the White House.
I wrote a series of stories outlining ways to help transit endure.
Lesson #1: Whatever you do, don’t cut service. Riders will leave – permanently.
Here are a few others 🧵
I wrote a series of stories outlining ways to help transit endure.
Lesson #1: Whatever you do, don’t cut service. Riders will leave – permanently.
Here are a few others 🧵
The Last Thing US Transit Agencies Should Do Now
Rising costs and widening deficits as pandemic aid runs out are challenging bus and train operators in many cities. But cutting service needs to be a last resort.
www.bloomberg.com
December 27, 2025 at 2:34 PM
2025 was brutal for US transit. Agencies faced budget deficits, flat ridership, and open hostility from the White House.
I wrote a series of stories outlining ways to help transit endure.
Lesson #1: Whatever you do, don’t cut service. Riders will leave – permanently.
Here are a few others 🧵
I wrote a series of stories outlining ways to help transit endure.
Lesson #1: Whatever you do, don’t cut service. Riders will leave – permanently.
Here are a few others 🧵
Self-driving cars are the most transformative transportation tech in a century.
In 2025, I wrote a slew of stories exploring their effects. 🧵
In @vox.com, I explained why the convenience of self-driven rides could bring crippling congestion. Cities should act now to mitigate the risks.
In 2025, I wrote a slew of stories exploring their effects. 🧵
In @vox.com, I explained why the convenience of self-driven rides could bring crippling congestion. Cities should act now to mitigate the risks.
A self-driving car traffic jam is coming for US cities
A century ago, cars remade America. Autonomous vehicles could do it again.
www.vox.com
December 26, 2025 at 3:26 PM
Self-driving cars are the most transformative transportation tech in a century.
In 2025, I wrote a slew of stories exploring their effects. 🧵
In @vox.com, I explained why the convenience of self-driven rides could bring crippling congestion. Cities should act now to mitigate the risks.
In 2025, I wrote a slew of stories exploring their effects. 🧵
In @vox.com, I explained why the convenience of self-driven rides could bring crippling congestion. Cities should act now to mitigate the risks.
Robotaxis make urban transportation more fragile.
If you want resilience, invest in transit.
If you want resilience, invest in transit.
waymo paused its robotaxi service as national weather service issued flash flood warnings in SF on christmas - @cnbc.com
www.cnbc.com/2025/12/25/w...
www.cnbc.com/2025/12/25/w...
Waymo pauses robotaxis in SF again due to flash flood warnings on Christmas Day
Waymo again paused it robotaxi service, citing a flash flood warning on Christmas Day.
www.cnbc.com
December 26, 2025 at 1:17 AM
Robotaxis make urban transportation more fragile.
If you want resilience, invest in transit.
If you want resilience, invest in transit.
America is an interesting place
December 25, 2025 at 9:42 PM
America is an interesting place
Reposted by David Zipper
Passersby are “unreliable”? You mean they don’t voluntarily take time out of whatever they’re doing to go up to a car that’s not theirs, that is probably tracking everything that happens, and fix the unanticipated problem of the door being left open?
“Because riders and passersby can be unreliable, Waymo pays workers in Los Angeles $20 or more for rescuing a robotaxi by closing a door, summoning help through an app called Honk that is like an Uber for towing companies.”
When robot taxis get stuck, a secret army of humans comes to the rescue
Waymo robotaxis get stranded when a passenger leaves the door open. Tow truck operators can get paid $22 to close a door and set them free again.
www.washingtonpost.com
December 25, 2025 at 6:17 PM
Passersby are “unreliable”? You mean they don’t voluntarily take time out of whatever they’re doing to go up to a car that’s not theirs, that is probably tracking everything that happens, and fix the unanticipated problem of the door being left open?
A San Francisco supervisor says that bricked Waymos slowed the fire department’s response to last weekend’s blackout.
If this is true, it’s very damming.
If this is true, it’s very damming.
Stuck Waymo robot(s) hindered SFFD from getting to the PG&E substation fire, according to Sup Mahmood who is calling for hearings re PG&E and Waymo.
Waymo has confirmed telops partially failed during this emergency (pic2).
Map of >30 stuck Waymo locations called into 311 (pic1).
archive.ph/OviuH
Waymo has confirmed telops partially failed during this emergency (pic2).
Map of >30 stuck Waymo locations called into 311 (pic1).
archive.ph/OviuH
December 23, 2025 at 11:18 PM
A San Francisco supervisor says that bricked Waymos slowed the fire department’s response to last weekend’s blackout.
If this is true, it’s very damming.
If this is true, it’s very damming.
Very much enjoying @ifbookspod.bsky.social's deep dive on Elon Musk.
@michaelhobbes.bsky.social: "There is no other physical object that screams 'I am an asshole' like a Cybertruck."
@michaelhobbes.bsky.social: "There is no other physical object that screams 'I am an asshole' like a Cybertruck."
Elon Musk
Podcast Episode · If Books Could Kill · 12/09/2025 · 1h 28m
podcasts.apple.com
December 23, 2025 at 10:52 PM
Very much enjoying @ifbookspod.bsky.social's deep dive on Elon Musk.
@michaelhobbes.bsky.social: "There is no other physical object that screams 'I am an asshole' like a Cybertruck."
@michaelhobbes.bsky.social: "There is no other physical object that screams 'I am an asshole' like a Cybertruck."
These were the best books about transportation and cities that I read in 2025.
🧵
🧵
December 23, 2025 at 12:38 PM
These were the best books about transportation and cities that I read in 2025.
🧵
🧵
Reposted by David Zipper
People want tiny basic electric cars. Automakers haven't responded, and safety regulations make it difficult, so they're buying golf carts.
Golf carts are puttering their way toward becoming a legit transport mode.
This year, Cleveland, Corpus Christi, and South Carolina officially legalized them on local streets. Major media outlets like the Wall Street Journal and CBS News have covered their soaring popularity (esp in suburbs).
This year, Cleveland, Corpus Christi, and South Carolina officially legalized them on local streets. Major media outlets like the Wall Street Journal and CBS News have covered their soaring popularity (esp in suburbs).
Why one Michigan town is regulating its golf cart boom
St. Johns, Michigan, is one of more than two dozen communities in the state to pass ordinances regulating golf carts on public roads.
www.cbsnews.com
December 22, 2025 at 1:42 PM
People want tiny basic electric cars. Automakers haven't responded, and safety regulations make it difficult, so they're buying golf carts.
2025 was a rocky year for US transportation. But there were some big wins.
At the top of the list: Manhattan congestion pricing. After 11 months, traffic is smoother, air is cleaner, and streets are quieter (but more bustling).
In Bloomberg, I shared a few more causes for celebration. 🧵
At the top of the list: Manhattan congestion pricing. After 11 months, traffic is smoother, air is cleaner, and streets are quieter (but more bustling).
In Bloomberg, I shared a few more causes for celebration. 🧵
When It Comes to US Transportation, 2025 Had Some Wins, Too
Amid federal-level threats and funding cuts, cities have still found ways to fight congestion, boost road safety and forestall the public transit death spiral.
www.bloomberg.com
December 22, 2025 at 1:31 PM
2025 was a rocky year for US transportation. But there were some big wins.
At the top of the list: Manhattan congestion pricing. After 11 months, traffic is smoother, air is cleaner, and streets are quieter (but more bustling).
In Bloomberg, I shared a few more causes for celebration. 🧵
At the top of the list: Manhattan congestion pricing. After 11 months, traffic is smoother, air is cleaner, and streets are quieter (but more bustling).
In Bloomberg, I shared a few more causes for celebration. 🧵
Reposted by David Zipper
The Abundance movement often points to environmental groups as the obstacles to building. But who actually files the lawsuits blocking projects? It’s not environmental groups. It’s been lawyered-up HOAs protecting property values all along. Regulation by litigation is the problem.
December 20, 2025 at 7:57 PM
The Abundance movement often points to environmental groups as the obstacles to building. But who actually files the lawsuits blocking projects? It’s not environmental groups. It’s been lawyered-up HOAs protecting property values all along. Regulation by litigation is the problem.
For your holiday reading consideration:
Humans break traffic rules all the time. Should autonomous vehicles do it too?
Humans break traffic rules all the time. Should autonomous vehicles do it too?
Cars are now being programmed to violate traffic rules. What could go wrong?
Me, in @fastcompany.com. (no paywall)
🧵
Me, in @fastcompany.com. (no paywall)
🧵
Tesla’s ‘Mad Max mode’ points to a big problem for self-driving cars
Mad Max mode exposes a risk for AV innovation. To stay competitive, computer-powered cars are emulating human drivers.
www.fastcompany.com
December 21, 2025 at 2:03 PM
For your holiday reading consideration:
Humans break traffic rules all the time. Should autonomous vehicles do it too?
Humans break traffic rules all the time. Should autonomous vehicles do it too?
Moderating a recent panel about transportation resilience, I asked whether self-driving cars make mobility networks more fragile due to the risks of malfunctions.
Anyway, this happened in San Francisco yesterday.
Anyway, this happened in San Francisco yesterday.
Waymo has halted service in San Francisco after numerous videos & images showed its autonomous cars snarling traffic during the blackout.
With traffic lights down, Waymos across the city stopped dead in their tracks at intersections.
missionlocal.org/2025/12/sf-w...
With traffic lights down, Waymos across the city stopped dead in their tracks at intersections.
missionlocal.org/2025/12/sf-w...
Waymo halts service during massive S.F. blackout after causing traffic jams
Waymo stopped its service across San Francisco on Saturday after numerous autonomous vehicles caused traffic jams in the city.
missionlocal.org
December 21, 2025 at 1:12 PM
Moderating a recent panel about transportation resilience, I asked whether self-driving cars make mobility networks more fragile due to the risks of malfunctions.
Anyway, this happened in San Francisco yesterday.
Anyway, this happened in San Francisco yesterday.
Bollards: 1
Car Bloat: 0
Car Bloat: 0
An American beast. Tamed.
#WorldBollardAssociation
#WorldBollardAssociation
December 20, 2025 at 3:04 PM
Bollards: 1
Car Bloat: 0
Car Bloat: 0
Reposted by David Zipper
What is the worst transportation idea of 2025?
@davidzipper.bsky.social: "I'd like to give this award to the American transportation secretary, Sean Duffy."
@davidzipper.bsky.social: "I'd like to give this award to the American transportation secretary, Sean Duffy."
December 20, 2025 at 12:30 PM
What is the worst transportation idea of 2025?
@davidzipper.bsky.social: "I'd like to give this award to the American transportation secretary, Sean Duffy."
@davidzipper.bsky.social: "I'd like to give this award to the American transportation secretary, Sean Duffy."
Reposted by David Zipper
Cars are now being programmed to violate traffic rules. What could go wrong?
Me, in @fastcompany.com. (no paywall)
🧵
Me, in @fastcompany.com. (no paywall)
🧵
Tesla’s ‘Mad Max mode’ points to a big problem for self-driving cars
Mad Max mode exposes a risk for AV innovation. To stay competitive, computer-powered cars are emulating human drivers.
www.fastcompany.com
December 19, 2025 at 1:18 PM
Cars are now being programmed to violate traffic rules. What could go wrong?
Me, in @fastcompany.com. (no paywall)
🧵
Me, in @fastcompany.com. (no paywall)
🧵
I'm about to hit send on the last 2025 edition of Paved with Good Intentions, my free newsletter about all things transportation.
Sign up here: www.davidzipper.com/newsletter
Sign up here: www.davidzipper.com/newsletter
Paved with Good Intentions — David Zipper
www.davidzipper.com
December 18, 2025 at 6:41 PM
I'm about to hit send on the last 2025 edition of Paved with Good Intentions, my free newsletter about all things transportation.
Sign up here: www.davidzipper.com/newsletter
Sign up here: www.davidzipper.com/newsletter
Reposted by David Zipper
Very much agree with this. I constantly draw on lessons learned from working within city hall.
One more thing about this, which is that if you ever return to journalism or decide to do nonprofit advocacy, you'll have gained a lot of incredibly valuable knowledge from public service.
My earnest advice to white guys with degrees who are struggling to make it in academia or journalism is that instead of blaming Black people you should consider pivoting to the public sector.
December 18, 2025 at 1:22 PM
Very much agree with this. I constantly draw on lessons learned from working within city hall.
Reposted by David Zipper
given how much cheaper touchscreens are than having to tool and manufacture physical switchgear, the safety data must be really bad for automakers to be voluntarily shifting back to real controls
New research finds that car touchscreens are so distracting that they induce "significant performance degradation" among drivers.
Meanwhile, in-vehicle touchscreens remain completely unregulated in the US.
doi.org/10.1145/3746...
Meanwhile, in-vehicle touchscreens remain completely unregulated in the US.
doi.org/10.1145/3746...
December 17, 2025 at 5:39 PM
given how much cheaper touchscreens are than having to tool and manufacture physical switchgear, the safety data must be really bad for automakers to be voluntarily shifting back to real controls