I will never stop banging this drum
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
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I will never stop banging this drum
On NPR's Up First podcast, I explained why CLEAR -- the line-cutting service masquerading as a biometric company -- is a pox on American airports.
This looks like a fun one. Free to register: mit.zoom.us/meeting/regi... @wesmars.bsky.social @strongtowns.org @visionzeronet.bsky.social
Finally. The use of screens is a way to cheap out on design and manufacturing. And it’s dangerous. One should never have to take their eyes off the road to look for a function like climate control or anything else. Good design will be kinesthetic and fall to hand.
In the US, federal regulators still pretend there is nothing dangerous about touchscreens that literally require drivers to look away from the road. slate.com/business/202...
Europe will only give a top safety rating to cars w/buttons (not just touchscreens): “The overuse of touchscreens is an industry-wide problem, with almost every vehicle-maker moving key controls onto central touchscreens, obliging drivers to take their eyes off the road.” etsc.eu/cars-will-ne...
Combating obesity by buying bigger pants, fails every time.
Nothing is certain except death, taxes, and highway engineers surprised by induced demand
I suspect this explains much of the “but think of the immigrants” hand-wringing re: traffic cameras. It reminds me of Donald Shoup accusing affluent car owners of using human shields when they claim poor people can’t afford to pay for parking.
Baffled by those who oppose traffic cameras because they “sacrifice the safety of our immigrant neighbors.” The alternative is for police officers to pull people over. Do you really think that’s safer for immigrants?
This was the spot-on post I was thinking of.
USDOT's insistence that cities remove colored crosswalks has nothing to do with safety and everything to do with LGBT censorship. From the latest episode of @lookbothwayspod.bsky.social
Found my Wario
A pile of research studies shows that small biz owners have no idea how their customers travel and that they consistently exaggerate the share that drives. Journalists who don’t acknowledge that reality are failing their readers.
Done properly, camera enforcement improves safety, advances equity, reduces bus delay, and improves emergency response time. No other techniques are as effective, especially on arterial streets.
This is a great read. I always say that when I have driven in areas with speed cameras, it is a far less stressful experience. People are driving an appropriate speed and are less aggressive. It makes driving safer *and* better.
One other point: Given what's happening with law enforcement, it seems like a good time to remove traffic violations as an excuse for cops to pull someone over.
Whatever its causes, the bogus controversy around automatic enforcement causes real harm. Skittish politicians end up blocking deployments that could save lives. So remind your local leaders that you want more traffic cameras. In all likelihood, your neighbors feel the same.
Politicians may also listen to activists claiming traffic cameras undermine privacy or equity. But 10+ city transport leaders told me residents seldom voice such concerns. In DC, cameras are most popular in low-income, Black Wards 7 & 8 where people are esp likely to die in a crash. Makes sense!
Another is media bias. Stories like this one (from Louisiana) quote numerous traffic camera haters without citing their safety benefits. Journalists also gravitate toward narratives with controversy. Such coverage skews popular perceptions (and political calculations).
So traffic cameras work, and most people like them. So why are they banned in states like TX, WI and MA (and often tough to deploy where legal)? One reason: Autocentrism. A minority of car owners protests – loudly – against any effort to constrain even illegal driving behavior. Politicos notice.
Most Americans appreciate the benefits of automatic enforcement. Researchers consistently find that a majority of people (including in cities as well as suburbs) back traffic cameras. Democrats are hugely supportive and Republicans almost evenly split. doi.org/10.1080/1538...
Many studies show that automatic enforcement curtails reckless driving: 🔹 US cities with red-light cameras have fewer crash deaths. 🔹 NYC school zone cameras reduced collisions 14% and speeding tickets 75%. 🔹 Speed cameras on Philly’s Roosevelt Blvd reduced traffic deaths. doi.org/10.1016/j.tr...
Context: Although speed and red-light cameras are most familiar, automatic enforcement can also nab drivers who violate bus lanes or pass a stopped school bus. Compared to police, cameras are far more reliable. And they’re not prone to racism.
There’s a widespread myth that Americans hate traffic cameras. It’s simply not true. On the contrary, researchers have consistently found that Americans broadly support using automatic enforcement to curb crashes. And for good reason: It works. Me, in Bloomberg 🧵
Eliminating through-traffic reduces crashes. Injuries and deaths fell14% at intersections within London's Low-Traffic Neighborhoods after through-traffic was diverted. findingspress.org/article/143455
While eyes are focused on Philly's transit catastrophe, there's also ominous news from Rhode Island. Frequency on RIPTA's critical R Line will fall from 10 to 12 min on weekdays & 15 to 20 min on weekends. Practically asking frustrated riders to get a car. eu.providencejournal.com/story/news/p...
Now available: Episode 4 of @lookbothwayspod.bsky.social On the agenda: 🔹 Rainbow crosswalks 🔹 Paratransit 🔹 American vs Canadian road safety + a dash of French Riviera urbanism Watch it on YouTube, or listen on your favorite podcast app
Trump is trying to force the EU to legalize US car bloat, and European safety leaders are furious: "Europe now risks being flooded with oversized, under-regulated U.S. pick-up trucks and SUVs – vehicles that are...completely out of step with Europe’s vision for safer, more sustainable mobility."
No, because Mamdani's best-known transportation proposal is a very bad idea
I don't agree with all of Mamdani's policy ideas, but he has consistently (and forcefully) said all the right things about street safety, bike lanes, and walkability.
The book's haunting final lines: "The problem of Nazism was primarily a problem of perception. In this respect Thalburg's difficulties and Thalburg's fate are likely to be shared by other men in other towns under similar circumstances. The remedy will not easily be found."
As an American, I felt a chill reading this passage explaining why people who didn't like Nazism still acquiesced. The addage about the boiling frog is entirely apt.
For a while, robust opposition to the Nazis in Northeim was led by Social Democrats. But rather than focus on an economic plan to win over an anxious middle class, the Social Democrats constantly attacked the Nazis as hoodlums and crooks (which they were). Didn't help.
First, fear breeds extremism. In Northeim, the Nazis’ rise was fueled by a middle class that was largely unscathed by the Depression but terrified of falling a notch on the social/financial hierarchy. They didn't actually want Nazism, but they were afraid.
Off topic for me, but this feels important. I just finished this classic account of Nazism's rise in a single German town (Northeim, called “Thalburg” in the book). Its applicability to the US is obvious, and its lessons startling. 🧵
I do. Golf cart sales are soaring in the US. Americans are increasingly using them as an affordable, fun mode of urban transport.
I do. Golf cart sales are soaring in the US. Americans are increasingly using them as an affordable, fun mode of urban transport.
It's maddening that folks living in Europe and Asia can choose from an array of useful minicars that are unavailable in the US b/c NHTSA & Congress say they're unsafe (unlike a goliath-like F-250, apparently).
Spotted in Bologna: A city-friendly Citroen Ami. One of many affordable European minicars that Americans can't buy.
Arggh, posting before coffee. Terrible idea. Thanks for flagging.
In European cities like Barcelona, London, and Milan, most vehicle emissions are from tires, road wear, and brakes -- not exhaust. Extensive report from @eiturbanmobility.eu: www.eiturbanmobility.eu/wp-content/u...
A story I wrote last year explaining the "highway expansions are good for the planet" fallacy that remains popular among state DOTs: "If highway expansions don’t relieve gridlock, they cannot reduce emissions. To the contrary, they worsen them."
Defenders of car-centric road planning claim that highway widenings reduce emissions (b/c they lessen congestion) while slow urban streets increase emissions (b/c they worsen congestion). Neither of those assertions is true.
I struggle to think of anything more certain to cause distracted driving than a truck broadcasting video ads on the highway.
Are two-way bike lanes more dangerous than one-way bike lanes, as many cyclists suspect? No. (at least, not in Barcelona) findingspress.org/article/1324...
Hot take: the 85th percentile rule is used because the US acts like speeding is a law enforcement issue only rather than an issue you can address with road design Traffic engineers just want an easy rule that passes the buck to law enforcement Law enforcement wants to not get yelled at by speeders
Picked up some swag while I was there. (Bologna is the first big Italian city to adopt a citywide 30 km/h speed limit -- thus the backpack.) More info on Dynamo: www.bolognaisfair.it/en/dynamo-la...
I mean, Italy does grow lemons...
Some kind of enclosed trike? I asked and got an answer that only confused me further.
The city owns the site, which is labyrinthine, leasing it cheap to Salvaiciclisti Bologna, a local bike advocacy group. Salvaciclisti and its partners offer bike parking, a do-it-yourself repair room, a bike shop, and a bar-cafe with lots of seating. (great place to enjoy a Campari Spritz)
A cool thing I discovered in Bologna: Dynamo, a former WWII air raid shelter that's now a huge underground bicycling hub. A place to hang out, fix your bike, and park securely by the train station.
Also, I kindly ask that any journalist writing about the US road safety crisis separate deaths among car occupants (which are relatively flat ) from those of people biking and walking (which have skyrocketed). The two trendlines are completely different. They should be treated as such.
More info below. The 85th percentile "rule" was proposed in 1937 -- for rural areas -- by the National Safety Council. doi.org/10.1177/0361...
What's wild about the 85th percentile is that lots of US states use it to set all speed limits, but the original idea (from the 1930s) was to let observed driver speeds shape speed limits on **rural roads**. It was never intended for urban areas w/pedestrians & cyclists!
"In terms of [crash] deaths per 100,000 population, the rates of deaths in the U.S are seven times higher than in Sweden, Switzerland and the United Kingdom."
If you’re referring to @zohrankmamdani.bsky.social, the problem is that “free” would cost NYC ~$1B/year, every year. Can’t exactly skip past that.
On the contrary, there's no evidence that fare-free transit reduces driving (or emissions). However, there is a *lot* of evidence that improving transit service reduces driving.
This is ultimately my concern with "free" transit. There's always a limited pot of money for transit investments, and dropping the fare to $0 means other elements of bus service are at risk.
Someone should ask @zohrankmamdani.bsky.social if he thinks Kansas City made a mistake choosing transit service quality over free fares
My nomination for dumbest urban policy idea of 2025: Melbourne's mayor wants to fine pedestrians who don't "keep left" on the sidewalk. He says the rule is needed before a transit expansion brings 500k people/week into Melbourne. Here's a better idea: **Expand the sidewalks**
Kansas City was one of the first US transit systems to go fare-free. Now the fares are coming back. The city & transit agency had a choice: Eliminate bus service or charge for trips. They chose the latter. (Low-income riders can still ride free.) Good move. Service quality > Free fares
One of the most popular car YouTubers put Rivian’s CEO on the defensive about car bloat. I agree—this is genuine progress.
Mahindra unveils a few more modest-sized and reasonably-priced EVs that Americans can’t buy. “Small, truly affordable electric SUVs may be missing from U.S. car showrooms, but they’re common on the other side of the planet.”
Bologna ❤️ 🚲
We're excited to welcome @davidzipper.bsky.social of @mit.edu as our keynote speaker for the 2025 PacTrans conference! David writes for @vox.com & @bloomberg.com & has also been published in @washingtonpost.com @theatlantic.com @fastcompany.com. Register now: pactransconference.com/keynote-spea...
True, but this is not her main point
You know how car touchscreens feel distracting? It's because they *are* distracting.
She’s not wrong
This car technology would save way more lives than autonomous vehicles
In every debate about extending public transit into a US suburban area, we always hear this. (Source in first reply.)
Waiting for a DC restaurant to do an “eat one, throw one” sandwich special
@davidzipper.bsky.social unloaded on Tesla in the latest episode: “It’s one thing to argue – which is debatable – that if you buy a Tesla and use Autopilot you’re agreeing to the limitations and risks of doing so." "But it’s another to basically treat everybody on the public road as a guinea pig."
It is a well known fact that people only like to spend time in cities where every square inch is dedicated to cars
In NYC (2023): Pedestrians & Bicyclists killed in crashes involving bikes: 10 Pedestrians & Bicyclists killed in crashes involving cars: 123 (Source: a860-gpp.nyc.gov/downloads/5h...)
Strange, I was told congestion pricing would turn Manhattan into a ghost town
Big picture: Canada is in the middle of the pack for road safety among rich nations, most of which have seen crash deaths fall. The US is the exception. IIHS exec: “It's not that Canada is hitting it out of the park and the US is doing just fine. Canada is doing just fine, and the US is not.”
FWIW, the IIHS/TIRF researchers dismissed a theory of US pedestrian deaths discussed in this viral NYT story: It's highly unlikely that automatic transmissions make American drivers esp likely to use smartphones. Canada has automatic transmissions too -- but no similar pedestrian death crisis.
What’s behind the widening gap in US and Canada crash deaths? A few plausible theories: 🔹 More car bloat in the US 🔹 More automatic and police enforcement in Canada 🔹 Stricter rules against drunk and distracted driving in Canada 🔹 Semi-trucks often have speed limiters in Canada but not the US
According to a new report by @iihs-hldi.bsky.social & TIRF, Americans’ greater “exposure” to driving explained virtually all the crash gap btw the US and Canada until ~2010. But from 2010-20, US crash deaths soared 18% while dropping 22% in Canada. Differences in VMT couldn't explain why.
Historically, the difference btw US & Canada crash rates has largely been due to Americans simply driving more. Reasons for that: 🔹 Canadians are more likely to live in big cities w/short trips 🔹 Canadian transit is better 🔹 Gas costs more in Canada 🔹 Driving rises with wealth, and the US is richer
Canada and the US are both car-centric, spacious countries. But an American is 2.5x more likely to die in a crash than a Canadian – and the gap is widening. My latest, in Bloomberg. 🧵
The article does link to the scientific paper (in the first line). Here it is: doi.org/10.1016/j.jt...
That process seems to already be underway
Long school commutes are bad for students. New research from China: "An additional 10 minutes of one-way commute time leads to a decrease of 0.017 standard deviations in students' scores." doi.org/10.1111/jors...
New research: Darkly-painted cars cause heat islands: "Dark-colored vehicles made the air around them 3.8°C hotter compared to the nearby asphalt road." (Darker cars are also more likely to be in crashes. www.researchgate.net/publication/...)
Can confirm: This lawless behavior is common throughout our nation's capital.
Actually, that's not true at all. I don't know who you are, but you've been loitering in my replies being obnoxious for months. Blocking you.
Mamdani has long been a forceful, knowledgeable, and consistent voice for street safety. Exciting to think about what he could do as mayor.
Trump is trying to force other countries to import Detroit's massive pickups, even though they flunk global car safety tests. There's a deeper challenge: Few consumers abroad need an expensive, bloated, fuel-inefficient truck.
Five years ago today, I wrote my first of 50+ stories about car safety. My motivation was simple: I couldn't understand why e-scooters were capped at 12 mph, but hulking SUVs could go 10x faster. The passage below still feels true. www.bloomberg.com/news/feature...
In The Guardian, London Mayor Sadiq Khan calls for urban 20-mph speed limits across the UK: "There is nothing to be gained by playing politics with speed limits – only people to be injured and lives to be lost."
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I just sent out a new edition of Paved with Good Intentions, the monthly newsletter where I share musings about transportation. Among the topics discussed: 🔹 Human intuition & dangerous car design 🔹 The challenges of Ivan Illich 🔹 A warning to bike advocates Online here: mailchi.mp/551fbd621b29...
As I've argued before, US automakers have put themselves in a precarious position by offering only pricey, massive SUVs/pickups. They're pushing families to ask whether they can get by with 2 cars instead of three, or 1 instead of 2 -- while e-bikes & golf carts are poised as disruptors.
The affordability of car-light living: "American households – maybe not most of them, but a significant percentage of them – have the opportunity to dump one of their cars and save a bunch of money." Urbanists should hammer away at this point, noting how e-bikes/cargo bikes make it easier.
It's a nice evening, so I'm off to meet a friend at a DC beer garden. Important to stay hydrated even while living in a lawless dystopia.
Whenever I try to explain to non-Americans why DC residents don't control our own laws or have a vote in Congress, they look at me like I'm insane. It makes absolutely no sense to them. Nor should it.
Agreed on both counts
When I see an auto exec claim that American preferences for bigger cars are immutable, I want to ask, "Oh really? How much did your company spend marketing SUVs and pickups over the last 40 years? How much on sedans and station wagons?" www.theverge.com/the-stepback...
