November 12, 2024 • 44 mins
Why are our roads unsafe, and who is to blame? Transportation expert Wes Marshall joins us to unravel the myths behind traffic engineering, revealing a surprising truth: the science we trust to keep us safe on the road might be more fiction than fact. With his provocative book "Killed by a Traffic Engineer: Shattering the Delusion that Science Underlies Our Transportation System," Wes aims to spark a critical reevaluation within the engineering community and beyond. Our discussion navigates the murky waters of road safety priorities, exposing the stark contrast between common fender benders and high-speed highway fatalities. The episode calls into question the societal and systemic factors that prioritize speed and power over human lives, emphasizing the urgent need to rethink the metrics and methodologies that guide our transportation systems.
Show Notes:
- Further Reading: Walkable City by Jeff Speck, Inclusive Transportation by Veronica Davis, Right of Way by Angie Schmitt, Transit Metropolis by Robert Cervero, The Bicycle City by Dan Piatkowski, Human Transit by Jarrett Walker, When Driving is not an Option by Anna Zivarts
- To help support the show, pick up a copy of the book through our Amazon Affiliates page at https://amzn.to/3YwX6aA or even better, get a copy through your local bookstore!
- To view the show transcripts, click on the episode at https://bookedonplanning.buzzsprout.com/
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Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Stephanie Rouse (00:12):
you're listening to the booked on
planning podcast, a project ofthe nebraska chapter of the
american planning association.
In each episode we dive intohow cities function by talking
with authors on housing,transportation and everything in
between.
Join us as we get Booked onPlanning.
(00:36):
Welcome back, Bookworms, toanother episode of Booked on
Planning.
In this episode we talk withauthor Wes Marshall on his book
Killed by a Traffic Engineer,Shattering the Delusion that
Science Underlies OurTransportation System.
I've had this book on our topreading list for this year's
season and was definitely notdisappointed.
Jennifer Hiatt (00:54):
Stephanie, I know that this has been your
world for a very long time, butI've just recently had to start
learning about transportationplanning and engineering, and
this book was so eye-opening.
I definitely feel betterequipped to have a good
conversation with ourtransportation engineers.
Stephanie Rouse (01:08):
And West does a good job diving into the
history of how traffic manualsdeveloped, their regulations and
recommendations, often taken asthe holy grail but lacking any
real studies or data to backthem up.
It's a great source for thoseof us working in communities
trying to make them more livable, but getting pushback from the
engineers, yeah.
Jennifer Hiatt (01:26):
I have to admit I always thought that you know
well, the engineers know whatthey're doing, so I never really
pushed back.
So now I have a better toolboxwith which to do so in our
conversations now.
So let's get into ourconversation with Wes Marshall
on Killed by a Traffic EngineerShattering the Delusion that
science underlies ourtransportation system.
Stephanie Rouse (01:46):
Well, Wes, thank you for joining us on
Booked on Planning to talk aboutyour book Killed by a Traffic
Engineer.
As a former transportationplanner, this is the book that I
had been waiting so long toactually be able to read.
I'm curious to know how has theengineering community received
your book and have you seen alot of pushback, or are you
seeing kind of light bulbsturning on in the transportation
(02:06):
field, starting to change theway they do business?
Wes Marshall (02:10):
Well, first of all , thanks for having me.
I will say the response fromthe engineering community has
been overwhelmingly positive.
But that doesn't mean therehasn't been some pushback.
And you know, I think thepushback especially has come
just with the title of the book,even though if those folks
actually read the book they'llsee I'm not.
So I've been happy to see someof that pushback because they're
(02:47):
still kind of sticking to theguns that I'm just sort of
dismantling throughout the book.
So I've spoken at some of themajor transportation engineering
conferences, like ITInternational, and nobody
punched me there.
I mean, in fact I think thatwas the first time I was at a
conference where people askedfor my autograph after I spoke.
So that seems a little bitweird, but it was good.
Stephanie Rouse (03:08):
That's good, because Chuck Maron seemed to
have the opposite effect on thetransportation community after
his book came out.
It seems like they startedsuing and really attacking him
instead.
So it's good to hear that thisbook has been received well.
Wes Marshall (03:23):
Yeah, I mean there was one person on the IT forum
asking me to resign and stuff,but again, he hadn't even read
the book and he was just tryingto make sure no one else did too
.
So I think there are some folksthat would rather this book
just go away, but that hasn'tbeen happening, so I've been
happy about that happy aboutthat.
Jennifer Hiatt (03:46):
Well, I'm pleased to report that in
Lincoln we have received wordthat a few of our transportation
engineers, including our deputydirector of what is Lincoln
Transportation Utilities, haveread it and don't seem to want
to punch you.
So that's good.
That's good.
Wes Marshall (03:57):
I have heard that some like state DOTs, like they
try to get in their library andthey've been told no, it's sort
of banned from that.
But those same state DOTs arehaving like secret book clubs
with the books.
So there's promising stuff.
There are a lot of engineersthat felt like I did.
They felt like something waswrong.
They sort of knew what we weredoing often didn't match up with
(04:18):
some of their favorite streetsor favorite cities or favorite
parts of these cities, and theyprobably felt the same
disconnect that I did that ledme down these rabbit holes.
Jennifer Hiatt (04:29):
And traffic engineering is really a newer
profession, even if, you like,say, compared city planning,
which Stephanie and I areplanners.
So that's perspective we'retaking.
So can you give a quick historyof the profession and how it
compares with other forms ofengineering?
I always found the idea that wecall it traffic engineering
kind of interesting.
So is that even the correctprofessional title?
Wes Marshall (04:51):
I mean, the terminology I probably use more
often is transportationengineering.
That's a little bit broader,but it didn't sound as good for
the sake of the title, so that'swhat I went with.
I mean, civil engineering hasbeen around like for thousands
and thousands of years, right,and civil engineering is usually
thought of as structuralengineering, like bridges and
(05:12):
stuff, or hydrology, you knowthings like that.
It's such a broad discipline,like we do environmental
engineering, like we haveconstruction engineering in our
department.
We even have GIS Transportation, like that element of it.
It's only maybe 100 years old,if that.
So that developed with theadvent of the automobile, where
we had this burgeoning need forsome sort of science to wrap
(05:34):
around what we were doing to ourstreets, our cities, in order
to adapt to that new technologyat the time.
So I feel like a lot of usthink this science is so well
entrenched and so well done.
But that's the thing like, whenyou actually start looking at
it it's like, well, no, evenback then we weren't, we knew
that, we weren't there yet.
(05:55):
But you know, we sort of nowthink that it's better than it
is and I will say it's not ourfault, like these thousand page
books that were all given.
I just assumed, as a youngengineer, that whoever wrote
these knew more than I did.
I assumed they did theirresearch.
I assumed that it was steepedin a hundred years of safety
science, and that just turns outnot to be the case.
So yeah, it is a relatively newdiscipline in the grand scheme
(06:18):
of civil or city planning orengineering, or even when you
compare it to things likemedicine.
Stephanie Rouse (06:28):
Yeah, and one of the terms or requirements
that comes out of these manualsthat I don't think has much real
science behind it and is themost frustrating term that I
keep hearing from our trafficengineers is warrants.
And you point out in the bookthat it's really a chicken and
the egg situation, where peoplearen't going to cross a
dangerous road but trafficengineers, based on the manual,
says we we need at least 93people, during peak periods or
whatever, to cross thisdangerous road before we can
(06:49):
actually put a signal in.
So where did this insane systemcome from and how can cities
get around it when theirengineers start citing this?
Wes Marshall (06:57):
Well, you're right , and that's the example I give
in the book is that one type ofstreet where you need 93
pedestrians crossing in the peakhour in order to get the
warrant for a crosswalk.
And you know, my thinking iswell, where does this 93 come
from?
Like, is there a paper theycite, is there some research?
And there isn't.
Like there's nothing behind it.
I mean, I'm sure it's, I guessI hope it's not completely
(07:19):
arbitrary, but there isn't muchwe can base it on.
And then when you think about,well, what does that actually
mean in terms of our design?
You know, I sort of joke likewhat's the best way to fix
pedestrian safety?
Well, we make the streets sounsafe that no pedestrians would
ever use it.
Therefore, we have nopedestrian crashes, but we all
know that's not what we want.
And the same thing goes when wethink about something like this
(07:40):
like, well, how do we make it asafe place to cross?
Well, we need 93 daredevils inthe peak hour to risk their
lives to prove to us that thiscrosswalk is warranted.
So when you just think aboutthe logic behind that, it
doesn't make sense, like there'svery little common sense there.
At the same time, you know,maybe a lot of engineers don't
really know this Like we feel,like especially the MUTCD.
(08:02):
Like you feel like that is themost standard of all our
guidebooks I mean the wordstandard doesn't really fit.
Most of them it's reallyguidebooks, guidelines but in
that case you feel like theMUTCD is kind of the highest
level towards the standard,because we're not going to
obviously do green stop signs orthings like that At the same
time.
When I searched through the book, I counted 167 times, I believe
(08:26):
, where they use the phraseengineering judgment.
Engineers always have leeway touse engineering judgment in
like the exact case you'retalking about.
Like we can say oh look,there's a school nearby.
We don't actually need to have93 people in the peak period
crossing to decide to put in asafer crossing or whatever the
reason might be.
But if you document it, if youhave a very logical, rational
(08:49):
process, you're taking away theliability worries that I think
engineers often have.
So we can use engineeringjudgment, we can use common
sense, but I don't thinkengineers feel empowered to do
so.
Either they don't know theyhave that ability, they don't
know how to do it, or they'reworried about things like
liability issues.
But you can, we can do better,and oftentimes it's a choice or
(09:14):
just not really understandingthat we can.
Jennifer Hiatt (09:16):
Even to the legal side of that.
I'm a lawyer by training,planner by passion, so every
time we would hear one of theengineers be like well, it's a
liability problem.
Like do you have a rationalreason to state why you're okay
with this decision?
Because that's like, that's theminimum legal requirement for
rational basis reviews.
Like can you document therational reason why you're okay?
Wes Marshall (09:39):
putting a crosswalk next to this park
seems like something you couldmeet pretty simply oh, yeah, um,
and we had these fears back inthe late 90s, early 2000s when
traffic calming was sort of new.
A lot of engineers like oh, wecan't do traffic calming, we're
gonna get sued.
And if you look at the researchafter the fact, nobody did,
nobody got sued.
And you know, I lay out theprocess, I call it the rational
(10:01):
process, which is exactly likeyou're describing, and I link it
.
I mean it's sort of liketactical urbanism, right, we
know we have a problem and wecan document that problem with
data, like, let's say, it'sspeeding.
If we have speeding data and weknow we're trying to fix this
speeding problem, and we come upwith a list of viable
alternatives, right, and we pickone that we think works best.
(10:21):
And then we collect data to seeif we're actually fixing the
problem we'd laid out.
You're protected from liability.
I mean, engineers historicallywill just throw up a sign, say
like even like a sign that saysdangerous intersection ahead,
and when you first see those,you're like what the heck are we
doing?
Like, why don't we just fix thedangerous intersection?
But when you step back it'slike well, why would you do that
?
And it's because of liability.
(10:42):
If you just warn people, itdoesn't fix the problem by any
means, but it alleviates theliability concern.
I'd rather see us be much moreproactive and start trying to do
stuff that may or may not be inthe manual, because we know we
have these problems.
They're known, we can documentit, we can get data on it and
let's do better.
Jennifer Hiatt (11:01):
I agree.
One of the things that I couldnot get over reading this book
because I am not atransportation planner by any
means is that traffic engineersoften treat a fatal collision
the same as a fender bender forcounts and whatever, and that's
been influencing our road designfor years.
Can you explain why we've beendoing this?
Wes Marshall (11:21):
Yeah, I mean, well , there's these, you know, from
the 1920s or all theseindustrial accident research.
They would have this pyramidand the idea is basically that
crashes are proportional interms of severity.
So if you just count, the totalnumber of crashes including
fender benders, like that'll beproportional to minor injury,
major injury, severe injury allthe way up to fatal.
(11:43):
So we don't really need to justfocus on the fatals.
I mean, we'll get the sameanswer no matter which level we
focus on.
And it might be true inindustrial accidents, but when
we translated that totransportation and we made those
assumptions that it was true,it turns out not to be the case.
I mean, I think you all knowthat when you look around cities
, like some of the densestplaces, you have such slow
(12:04):
speeds and you have a lot of,maybe, traffic congestion, so
you have a lot of fender benders, right, but that's not where
people are dying on our streets.
It's where you know thefundamental physics of it, like
you need speed, mass and that'swhat gives us the force and end
up having people lose theirlives.
So you often get completelydifferent answers Like our
highways don't have many fenderbenders, but that's where you
(12:25):
have a lot of fatal crashes andvice versa, in cities where you
have a lot of fender benders butnot many fatalities.
So if we made the mistake ofassuming that safety is just
based on fender benders, youstart taking these rural or
highway type designs and pushingthem through cities and that's
where you start gettingfatalities there, because we've
(12:46):
conflated the problem.
Jennifer Hiatt (12:48):
I find it interesting too, though we had a
very bad intersection here inLincoln.
People were somewhat regularlydying at this intersection.
Then we put in roundabout andmore accidents happened, but
nobody died.
Some of our residents were like, but more accidents are
happening here.
This is ridiculous, butnobody's dying.
People were dying.
(13:09):
You can't win for losing inyour profession, really.
Wes Marshall (13:12):
No, it's a matter of priorities.
I think I named that chapter.
Don't sweat the small stuff,and the small stuff is fender
benders.
That's a concern for insurancecompanies.
It's annoying and all, and wecan improve that too.
But let's start with whatactually matters are people's
lives, and, for whatever reason,we treat road safety,
especially things like liveslost on the road, as the cost of
(13:35):
doing business, as opposed tolike the public health emergency
that it really is.
Stephanie Rouse (13:39):
Yeah, it's really interesting on crashes
how we treat them based on typeof mode.
So we just accept the very highrates of traffic deaths on our
roads every year, but one planewith a couple hundred people
goes down and there are so manymore investigations and it's all
over the news, but no one'sreally talking about the massive
(13:59):
lives lost on roadways everyday.
Wes Marshall (14:01):
The massive lives lost on roadways every day.
That's funny.
My safety class this weekthat's exactly what we talked
about.
I was trying to teach aboutexposure, like the idea that we
can't just look at total numberof crashes or fatalities, and
it's not really apples to apples.
You want to normalize it bysomething, and we talked through
, we tried to actually calculatehow safe it is to be in a
(14:22):
commercial airline or how safeit is to be on a train versus
how safe it is to be in a car,and I think we found the plane
was 121 times safer than a carper mile and the train was
something like 40 or 50 timessafer than a car.
But then we talked aboutexactly what you said, even when
the Boeing door stuff was anational issue.
(14:44):
Right, this was something thateverybody was up in arms with.
Pete Buttigieg was out theretalking about it, or we had some
train crashes, I think, like inIndiana or something.
I mean same thing, but at thesame time every night you turn
on the news like somebody diesin a car crash and it barely
makes a headline and far morepeople are dying on our roads
and car crashes and pedestriansand bicyclists than die in
(15:08):
planes and trains, but forwhatever reason, we don't treat
it at all in the same way andpart of it.
You know sort of the differencebetween like a dripping faucet
and like a fire hose.
Right, when a plane goes down,it's like 200 people and, yeah,
it makes perfect sense why wewant to fix that.
But even when more than 200people die in a single day on
the roads, it doesn't feel thatway Now.
So even around the world like,if you look at the numbers, more
(15:28):
people die every day on theroads than died in 9-11, but
we're not really doing muchabout it.
I saw TRB put out a reportearlier this week.
The graph shows fatalitiesgoing up, but fatalities per
like vehicle mile travel aregoing down, and the caption said
that roads are safer than ever.
I'm like, wait a second,they're not.
More people are dying.
(15:49):
How is that safer than ever?
It's because they're measuringthe wrong thing.
Stephanie Rouse (15:54):
We track annually progress on our
comprehensive plan and one ofthe metrics is vehicle miles
traveled and crashes per vehiclemiles traveled.
And after reading that sectionI was like, oh, maybe we should
stop showing that, becausethat's not really helpful.
Wes Marshall (16:08):
Well, it's helpful if you're looking at the safety
, maybe, of a particular road orintersection, right, and you're
comparing, like that facility,but it's not helpful for us
humans, right?
You care about it much morelike any other public health
measure, and every other publichealth measure is a per
population metric.
You know, for a while I waslike man.
Us traffic engineers werepretty dumb to do that and
(16:30):
that's one of the you know, oneof the rabbit holes I dug down
and I found out that you know,sometimes, like we admitted that
we didn't know enough and we'retrying to get better, but that
is one where it's literally.
The CEO of Studebaker didn'tlike in the 1930s, how cars are
being made to look very unsafe,so he made the right point that
we need an exposure metric, buthe just picked the one he liked
best.
(16:50):
He wrote a book about it.
This textbook right behind me,seven Rows to Safety, paul
Hoffman, in 1939.
And he came up with a metric ofmeasuring it per vehicle mile
travel.
And then he barnstormed thecountry selling this new metric
to this brand new discipline oftraffic engineering.
We started using it and 1966 or65, the USDOT put this into
(17:14):
their official metrics formeasuring traffic safety, and
we've been doing it that wayever since, but at the same time
, when you think about what thatactually means, there's two
ways to improve safety.
One is we reduce fatalities orsevere injuries.
The other way is to increasedriving.
The more you drive, the saferyou seem, and we've been
building our transportationsystem in the streets based on
(17:35):
the latter.
Stephanie Rouse (17:36):
And so that's one of the examples of we've
just been doing this way forever.
We keep talking about bad datagoing into some of these manuals
this way forever.
We keep talking about bad datagoing into some of these manuals
and some of them take foreverto update.
The MUTCD was this very longdrawn-out process back and forth
negotiations, good changesgetting cut.
Why is it so hard to changethese manuals when we know
they're not accurate?
Wes Marshall (17:57):
Well, inertia is one of them, part of them.
There's a lot of vestedinterest in sort of keeping the
status quo, not just intransportation but in sort of
everything.
So there's some entrenchedfolks on these things.
But I don't know, like theMUTCD I'm sure you saw, you know
there was that public commentperiod and do you remember how
many wasn't there, like 10,000or something crazy like that?
(18:18):
Yeah, it was high, yeah, andthere's some improvements in the
latest version that you knowstill yet to be adopted by all
the states, but it's still notwhat we need or want.
And that's the case with all.
I mean the Ashford Green Bookand a lot of the other ones.
The Highway Capacity Manualthey're similar.
Like you know, I was actuallyjust invited yesterday to speak
at the TRB, the TransformationResearch Board.
(18:39):
We have a giant conference inDC or like 15,000 people there
and the committee that looks atcapacity they're the ones that
are helping write the highwaycapacity manual.
They want me to come speakabout.
I mean the fact that level ofservice isn't this thing handed
down to us on Mount Sinai, toMoses from God.
It was sort of haphazardlythrown together in a meeting,
(19:02):
just like the meeting we'regoing to have in DC in January
where, like some guy over hereis like, oh, we need to do this.
And they're like, oh, in thefuture, we need to make sure we
add safety to this.
And then the next iteration weremove that sentence.
We never added safety.
And so when you see how itactually came together, I think
a lot of engineers it sort ofblows their mind that oh, this
wasn't this very rigorousscientific process.
(19:22):
This was a meeting just likethe one we're in, where people
are negotiating for what theythink is best for the time being
.
Jennifer Hiatt (19:31):
Well, and to that end, so many of these
manuals were new to me as I wasreading about them, so I had to
look them up and read about themin our book, and it seemed that
each manual oversteps itspurpose in many ways.
So, for example, in the bookyou say that the MUTCD is
supposed to provide standardsfor traffic signs, signals and
markings, but it also feels theneed to add its two cents on
setting speed limits, forwhatever reason.
(19:52):
Doesn't this ultimately createa confusing situation and make
it difficult to apply standardsacross the board?
Wes Marshall (19:58):
Well, the whole idea behind these from the get
go was that, especially in theUnited States States, where
things can differ from state tostate, like we need some
reciprocity, we need somesimilarities when you go from
one state to the other.
I mean stoplights shouldn'tflip or stop signs shouldn't
look there, all that sort ofstuff Like we need to have a
commonality.
So that was the idea behindthem.
But you know, over time, youknow maybe there's some bloat,
(20:21):
maybe there's some.
You know, maybe there's somebloat, maybe there's some.
You know group think, like youknow you've been in meetings and
there's a lot of people likeit's easier to kind of pick what
you think is the safe option asopposed to maybe picking the
right option and transportation.
I think this is tricky becausea lot of the stuff that happens
is very counterintuitive.
So our theory, you knowsomething basic, like wider
roads are safer because it givespeople a factor of safety.
(20:43):
Um, if you're speeding, ifyou're drunk or something,
you'll still have space to runoff the road and you're going to
live, and that makes perfectsense.
Maybe if you're a structuralengineer or if you're someone
designing a culvert, motherNature doesn't care how big I
make the beam on this building.
It's not going to be anywindier, it's not going to rain
anymore, so the culvert could bebigger, the beam could be
bigger, the beam could be bigger.
But in transportation peoplebehave based on the
(21:05):
transportation system you put infront of them.
So, yes, the theory makes sense, give people more space.
But if they start going faster,or maybe not paying as close
attention to the road or theside of the road, or they look
at their phone longer, whateverit might be, I mean, the
empirical results aren'tmatching the theory.
And you would think in ascientific discipline we'd fix
that, we would learn, we'd getbetter we.
(21:26):
But for some of the reasons youtalked about in the question is
like we haven't.
Like we, that group, think thefact these manuals have been
around for so long, the factthat we think they're based in
science, has kept us maybe fromchanging them, from pushing
forward, from trying to makethem better, and hopefully, what
my book points out is they'renot as scientific as any of us
were led to believe.
So we don't need to hold ontothem as dearly as we think.
Stephanie Rouse (21:50):
Yeah, and knowing that we're probably not
updating the METCD anytimesooner, hopefully that gives
engineers more license to useengineering judgment, which is
actually built into the manualto use.
Wes Marshall (22:01):
I hope so.
I mean, I know this book is notspecifically meant for traffic
engineers.
I hope they read it.
I hope they do better.
But I also want to give peoplein positions like you, or
advocates or people like that,enough ammunition to maybe more
effectively argue with anengineer, like I've heard you
all in your podcasts complainabout.
You put these great planstogether and then where do you
(22:22):
get your pushback right?
So often not even from thepublic is from the engineer Like
oh, that looks great, but wecan't actually do that.
So you know you get enoughinformation from my book where
like oh, like what he's actuallysaying there, what she's saying
there isn't really a standard.
Like they do have engineeringjudgment and you can point this
out to them even if they don'tread the book.
But I'm glad to hear they did.
Stephanie Rouse (22:43):
Yeah, we'll definitely pull in some sections
and forward them on the nexttime they push back on our ideas
.
So no discussion oftransportation is going to be
complete without addressingautonomous vehicles, and you
rightly point out in the bookthat this isn't the silver
bullet that's going to fixeverything.
Even if we could get everyoneinto an autonomous vehicle and I
hadn't really thought of it too, about just beyond the
(23:05):
affordability piece there'sgoing to be people out there
that don't trust this technologyand will never adopt it, and so
we're never going to geteveryone in autonomous vehicles.
So there's still going to beplenty of us with our own
autonomy in a vehicle or walkingor biking.
What are some of the other redflags with this reliance on
autonomous vehicles that youdiscuss in the book?
Wes Marshall (23:25):
I think if you look at the benefits of
autonomous vehicles, you knowthe thinking is like human error
is a big problem in our crashes.
It's like 90, they blame it on94%, but that's something I sort
of disprove in the book too andthat we're going to get all
these benefits within thisautonomous system.
So we're not going to needparking, we're not going to need
whatever it is.
We get all the benefits.
(23:46):
But if you look at that list ofbenefits, you only really get
them if every car on the road isautonomous.
I remember I was in Australiafor sabbaticals, I was in Sydney
and they used to do this thingcalled city talks and they
brought in these outsidespeakers, which were great and
hundreds of people came to this.
And I saw one by this guy fromMIT and he was showing this
awesome animation of, like thisconventional intersection where
(24:09):
delay is happening, cars arebacking up, and he showed an
autonomous intersection whereevery car is getting a
reservation and just flyingthrough this intersection like
crazy.
And he declared the latter onethe future of urbanism and he
got the standing ovation fromlike 200 people.
I'm like wait, what?
Like what if you have one humandriver or one pedestrian or one
(24:30):
bicyclist.
Like that doesn't workwhatsoever.
Like this might be the futureof the middle of nowhere, but it
is not the future of cities.
And when you start thinkingabout even if we can get the
technology right, like yes,waymo's ahead of other folks and
doing the robo taxis in SanFrancisco and places, but you
don't get the same benefits whenit's just a few of them, and
(24:50):
how can we get everyone to do it?
I mean, you know, I joke thatthere's a reason why there's
like 11 Fast and the Furiousmovies and they've made like $10
million or whatever it isbecause people love driving and
there's a huge culture around it.
So to get everyone to shiftisn't often just the technology
problem, it's a social orcultural problem and it might
(25:13):
not go as far as like the gundebate goes, but you're going to
have some people saying you'regoing to pull this steering
wheel out of my cold dead handsand like we're not going to get
there right.
So there's so much behind it.
And then, if you, I read PeterNorton's great book Autonomorama
recently and like he basicallybrought this back you know 50,
60 years where we've had thistechnological carrot kind of
(25:36):
dangling in front of us, andit's always five years in front
of us and it's been five yearsin front of us for 60 years and
it's still there.
It changes what that technologyis, but it's still hanging in
front of us.
And it's been five years infront of us for 60 years and
it's still there.
It changes what that technologyis, but it's still hanging in
front of us.
So there's a lot of people Iknow that are great engineers
but they just don't really worryabout safety because they feel
like AVs will fix it.
And it's just not true.
It's easier said than done.
(25:58):
It's much more complicated interms of the social, cultural
than we think.
Even if we get the technologyright, yes, we'll reduce some
types of crashes, but with everytechnology over the course of
history it leads to other typesof errors.
So I mean, just interactingwith these different
technologies isn't the same.
10 years ago I remember drivingup to the mountains with a
(26:20):
neighbor of mine.
So I live in Denver and if youwant to go skiing or
snowboarding, go an hour pluswest.
Then there's tons of snow andtons of that kind of stuff.
And at the time I think he hada new BMW and he was just
changing lanes willy nillywithout looking.
I'm like man, what are youdoing?
Shouldn't you look?
He's like oh no, the car willtell me if there's a car in the
adjacent lane.
So if he added that technologyto what he had done before, if
(26:43):
he was still looking over hisshoulder and using the mirrors,
and you layer that technology ontop, it would be safer.
But when you replace thetechnology, maybe not.
Our cars get dusty in themountains, so maybe it's not
working or maybe the sun is acertain glare.
The technology can't see thatcar, whatever it might be.
The safety benefit isn't asclear cut when you think about
(27:05):
it this way.
And even those cars now thatare supposed to stop for
pedestrian I mean, the researchshows they don't work in certain
lights.
They don't work as well withdarker skin.
You know these technologies arekind of a little bit racist
when you think about it that wayand we don't want that either.
So if we start shifting how webehave based on technology and
this relates to the last pointswe were talking about it's not
(27:27):
as clear-cut.
Jennifer Hiatt (27:28):
So it's, it's just not that simple every time
I read about technology that'ssupposed to be able to like
identify people and how it justhardly ever identifies people
with dark skin.
I think about the episode fromthe tv show better off dead.
If you haven't seen it,everybody should go.
Watch's funny.
Got canceled after like twoseasons, but they have a whole
episode where it's like the costbenefit of putting in all of
(27:49):
this automated stuff versus theuncomfortableness of their
employees of color.
It's like they couldn't washtheir hands, lights didn't turn
on, cars don't stop for them.
This seems like a bad future.
Plus, I've seen too manydystopian movies and read too
many dystopian books.
You're not putting me in an AVcar.
Wes Marshall (28:06):
Yes, my wife watched that show.
That's the one on Netflix.
It starts off, didn't it?
Like the friend's husband diedin a crash, or something like
that I saw a couple of thoseyeah.
Jennifer Hiatt (28:14):
Speaking of cars , I know transportation
engineers don't design cars, butshouldn't you guys have maybe
(28:37):
some kind of say in that.
Wes Marshall (28:38):
So we create roads you can drive 120 miles per
hour on.
But why does any car reach 120miles an hour when nowhere in
the country has a speed limitover 90?
It doesn't make sense.
I do have some chapters aboutcars and how fast and big they
are, and you know I joke.
When I was 16 and I boughtmyself a car, I was pretty
thankful it couldn't go morethan like 75 or 80, because it
was a pretty crappy car, becauseat that time I drove as sort of
fast as I could everywhere Iwent.
And now if you look at theodometers on a lot of cars
they're like 140, 160, 180.
(28:59):
I've seen a sum of 220 and 240.
We don't need that unlessyou're like driving NASCAR or
Formula One.
But there is, for whateverreason, like thinking that more
power equals like more safety.
I mean there's also social,cultural issues.
You know, talking about theFast and the Fur came to Denver
(29:22):
like people were crazed abouthow fast they go and try to do
some geofencing around, like our16th Street Mall, which is a
pedestrian zone, to make surethese scooters were forced to
drop down to three miles an hourin that zone.
I know DC does somethingsimilar.
They couldn't get it to workhere in Denver but for whatever
reason, everyone was okay withthat.
But when you say the same thingabout cars, people lose their
(29:44):
mind.
Like oh, that's un-American,like you can't tell people what
to do and I know, for whateverreason.
With things like even red lightcameras, speed, the
conversation devolves intofreedom.
Big brothers watching me Likethe conversation is never about
safety.
If we can keep the conversationon safety, we'd be better off.
You know, if safety really wasour first priority, our cars
(30:04):
would be bubble wrapped.
They would go no more thanmaybe 20 miles an hour in cities
.
But it's not.
You know there's a group ofpeople that are trying to make
money off of cars, but we'vealso built a transportation
system where most people live ina place where driving is really
the only viable option.
And then when you think aboutthe rational decision of those
folks, like driving in a big SUVmakes the most sense too right,
(30:24):
and to me I feel like it's onengineers to fix that, on
transportation planners and cityplanners to fix that.
At the same time, there is arule for policy in terms of
limiting speeds or limiting carsize, or even just making folks
that use a bigger, badder carpay more in insurance right.
Use a bigger, badder car, paymore in insurance, right.
Like there is more risk thatyou're putting out there into
(30:45):
the world when you drive a trucklike that than if you drive
like a Mini.
Cooper or something right that'snot anywhere embedded into,
like the costs that are put onto folks that do that.
Stephanie Rouse (30:57):
When you're talking about, if we really want
things to be safe, we wouldn'tbe driving more than like 20
miles an hour.
And it was really interesting.
I had friends from Minneapoliscome in last weekend and when
they got there they were like,oh, is it 35 miles an hour on
your street?
And it's kind of a sort ofresidential, but it's
technically like a collectorstreet in Lincoln, but it feels
more like a residential street.
And I was like yeah, no, it's35.
(31:18):
And they're like, oh, that'sweird, it's 25 everywhere in
Minneapolis now.
And I was like, yeah, no, wehave streets that run through
town that are 45 miles an hour,like we are not really
prioritizing safety in ourcommunity, like Minneapolis and
some other communities are.
Wes Marshall (31:33):
Yeah, I mean, if you look at the data, you know.
I mean there's a lot ofdifferent numbers that look at
it, but in general, like apedestrian that gets hit at 20
miles per hour, it's maybe a 15%chance of dying.
At 30 miles an hour it's closerto 45%.
At 40 miles an hour it's like80, 85%, right?
If you just know those numbersand if you say safety is our
(31:54):
first priority, it's obviouswhat to do.
But we're not doing that inmost places.
Jennifer Hiatt (32:00):
I think the diagram was in your book or it
was in some extra research I wasdoing to do, but we're not
doing that in most places.
I think the diagram was in yourbook or it was in some extra
research I was doing to prepare,but it showed like a big truck
and a car and the impact zone ona human body and I am five foot
tall and never really thoughtabout like where a car would hit
me if I got hit and that waslike a terrifying realization
(32:20):
that my head isn't even in likea sight line of maybe half of
the cars that people sell thesedays or buy or drive.
Wes Marshall (32:27):
Oh yeah, I've seen some.
I don't have any images in mybook whatsoever, so there
probably wasn't one you sawthere, but I talk about that
exact issue, right?
So if you are hit by like aHonda Civic from 20 years ago,
you get hit in the legs, youroll up into the hood, you may
hit the windshield, you mightbreak your legs, but you're
often going to be okay.
If you get hit by an SUV today,you get hit like in the chest,
(32:47):
you get knocked down, your headhits the pavement and you get
run over and you're much morelikely to die.
I'm doing a talk at the SafeRoutes for School conference in
a couple of weeks and, like oneof the things I'm thinking about
is I mean just the fact thatlike even something design-wise
as simple as where we put thestop bar in front of like a stop
sign, like you know you knowthere's a lot of videos on this
(33:09):
like in a lot of our SUVs today,like there's that one from
Indianapolis where they had 13kids sit down in front of that
car and the driver couldn't seeany of them, right?
Well, how would you design theintersection differently?
Well, you should push the stopbar back like 20 feet, right?
If our car is going to be thisbig, if kids are this little,
let's design this differentlyand daylight the intersection,
push the stop bar back.
(33:30):
There's simple, obvious, commonsense things to do, but we're
not doing them.
Stephanie Rouse (33:35):
So another term that comes from the manuals
that deals with speeding is the85th percentile another one of
my least favorite terms I keephearing from our engineers.
So the concept is you know, wematch our speed limit based on
what 85% of the drivers aregoing, then the drivers take
that speed limit and up theirspeeds, and then it's just this
continuous cycle of raisingspeed limits.
(33:57):
Why is it so hard for engineersto just design a street for
lower speeds, that they actuallywant to see an action, versus
waiting for drivers to drive aspeed and then adjusting?
Wes Marshall (34:07):
Well, this is a good example of the theory kind
of trumping empirical results.
We have this theory that aslong as all drivers are in the
same maybe 10 mile an hour pace,like most of our drivers are in
that same short pace, that'show we, like most of our drivers
are in that same short pace.
That's how we get to safety.
It doesn't matter if that paceis 80 or 20, safety is better,
(34:28):
right, and that research goesback to David Solomon, like this
older research when you look atthe original study that led us
to think that it's been debunkedhalf a dozen times over, based
on just these rural roads inTexas, and he showed something
that, like these slower cars arehundreds of times more
dangerous than the faster cars,and it just wasn't true.
(34:50):
If you dig into the actual data, it's really just people
turning in and out, of, like gasstations on these rural roads
that are getting hit from behindby the faster cars.
And all the empirical resultssince then shows us that higher
speeds leads not only just tomore crashes but worse overall
safety in terms of fatalitiesand severe injuries.
But that thinking has stuck andwe have this mantra if you look
(35:11):
at, like in the MUTCD, how weset speed limits.
It's based on the assumptionsthat drivers are reasonable and
prudent.
Whatever road you put in frontof them, they'll tell us how
fast and safe to drive.
Like is that true?
Do you feel that's true?
Probably not, but that's stillwhat we're doing.
So we let drivers vote withtheir feet as to how fast the
speed limit should be.
And I mean, I give some crazyexamples in the book, like
(35:33):
there's one from Californiawhere these college students at
Cal State Northridge were killedon the road right next to it as
pedestrians.
And you know, like, oh, we gotto do something about safety.
So what do they do?
They did a safety study, theydid a speed study and they
raised the speed limit.
It's like, wait what?
We raised the speed limit onthis road next to a college
because a pedestrian was killed.
And that's how you're going tofix safety.
(35:53):
And guess what?
More pedestrians were killedand they did it again.
And it just doesn't make anylogical sense.
And there's the other examplefrom Utah, where they had this
problem with wrong-way driverson their highways and their
thinking of how to fix thatsafety problem was to do a speed
study and raise the speed limit.
It's like how in the worldwould that possibly fix this
wrong-way driver problem?
(36:14):
But that's the thinking is thatthis 85th percentile is the way
to safety, and it's just nottrue and the research doesn't
back it up.
But we were taught that this ishow we get safety, so that's
why we're still doing it.
Jennifer Hiatt (36:29):
Bothers me.
Wes Marshall (36:30):
It should.
That's the thing, right.
It bothers me and that's why Iprobably a tinge of anger in a
lot of my writing, because I'mangry about some of this stuff,
right.
Stephanie Rouse (36:42):
So a lot of it came through in your footnotes
and I loved all of thereferences and the snarky
comments.
I never read footnotes, butthose ones I definitely did.
Wes Marshall (36:49):
Thank you, it was good to hear.
Jennifer Hiatt (36:51):
Never skip the footnotes.
So, as you mentioned at the topof the episode, though, at the
end of the day, you're notactually saying that
transportation engineers areintentionally designing bad
roads or actually going out oftheir way to try and kill people
.
So, ultimately, what steps areyou proposing?
The profession needs to startdoing better for our cities and
people who live in them.
Wes Marshall (37:10):
So I link it to medicine and doctors.
Right, doctors have been aroundfor similar to civil
engineering like 5,000 years,let's say, and it wouldn't be
hard to say, you know, the firstthousand years after
Hippocrates.
Let's say, and it wouldn't behard to say, you know the first
thousand years after Hippocrates, that they were probably
killing more people than theysaved.
But it's an empirical science,they were getting better, they
were learning, they're doingtrials, whatever have you in the
(37:31):
medicine world, and now I meanit's not perfect, but they're
still trying to get better andbetter.
Like that's the thinkingTraffic engineering,
transportation, engineering.
We're only 100 years old andwhat I'm saying is we're still
in that stage, like we're stillkilling more people than we save
.
We just don't know it.
And our problem is we havebecome less of an empirical
science.
(37:51):
Like we're still steeped inthese theories that have been
disproven and to some extent itfeels more like a religion than
a science.
So how do we get better?
We need to go back to being ascience, get back to being an
empirical science.
Do things like the rationalmethod or tactical urbanism.
See what works, test stuff, useengineering judgment and learn
(38:14):
and get better.
And look around at the cities,the streets that work.
I know I grew up right nearBoston and that's what kind of
led me down some of these pathsis the stuff I was building as a
consultant, you know, worked aslike seven years in that space
was never as good as what I sawaround me.
I was like, well, why can't webuild a street like that?
And you look it's like, well,it's illegal to given, you know,
(38:38):
certain guidelines or certainparking minimums or level of
service, and these are ourfavorite places and cities that
we have engineered out of beinga possibility.
Then we look at, well, where dowe put most of our engineering?
Like in most cities, thearterial network that the DOTs
(38:58):
are often in charge of are ourmost engineered roadways.
That's where we put all of ourscience and thinking.
And then you look every citythat's done one of those high
injury network studies where 50or 60% of deaths take place in
like 5 or 6% of the roadway.
Which roadways are we lookingat with that?
It tends to be those samearterial roadways where we put
(39:21):
all of our engineering thinkinginto, and you see the disconnect
.
It's not hard to see it.
So that's what we need to startdoing is getting back to being
an empirical science, gettingback to actually looking around
and seeing, well, what works.
What is maybe the corner radiiof this street that we all love
and it works today?
What is actually thatmeasurement?
(39:42):
And you see, well, we can'teven build that today.
Well, maybe we should change.
What we can build today andthat is where I hope it starts
going is more in that, empiricalas opposed to theory-based
direction.
Stephanie Rouse (39:54):
I would love to see that as well.
And, as this is booked onplanning, what books, in
addition to yours, which we allrecommend everyone, of course
check out that you wouldrecommend our readers read?
Wes Marshall (40:05):
Yeah it's funny, while I wrote the book for like
the three plus years there, Ididn't read any of the
transportation books.
I didn't want to be influencedby the other books that were
coming out.
So I kind of went in my caveand did my stuff During that
time.
I read a lot of fiction andstuff, but not anything
(40:25):
transportation.
I actually stopped listening toeven the smart podcasts.
I only listened to really dumbpodcasts for a few years in
there.
When I came out of the cave Istarted trying to catch up with
everything.
So I know some of these authorshave been on your show, like
Angie Schmidt and like DanPiakowski and Jeff Spex, like
his new Walkable Cities book,human Transit by Jared Walker,
the second edition I just readrecently the ones I was
(40:46):
surprised how much I loved.
I just read Anna Ziver's whenDriving is Not an Option and
Veronica Davis I think you hadon your show too Her Inclusive
Transportation.
I loved that book.
Going back in time, like someof the, I first got into this
world, like Donald Shoup's workwas always.
I started getting into thateven before his High Cost of
Free Parking book came out andyou can maybe see some of his
(41:07):
same approach.
They're kind of shedding lighton the lack of science behind
parking.
That I do with a lot of otherthings Transit, metropolis, the
Robert Severo book from like thelate 90s, I think.
There's so many books out there.
I'm actually curious more whatyou guys are reading these days.
Stephanie Rouse (41:24):
You can see what we're reading on our show
Two books.
We're kind of getting into agroove of two books a month
which is hard to read, much elsethan what ends up on this
podcast.
Wes Marshall (41:32):
Yeah, I'm sorry.
My book was like 400 pages.
That makes it harder.
Stephanie Rouse (41:36):
It was a pretty good read, though Just the way
you wrote it made it digestible.
Jennifer Hiatt (41:42):
I was going to say it went very quickly.
When you pick it up it lookshefty, but when you start
reading through it it's verysimple to get through.
Like so I can study easier todigest.
Wes Marshall (41:50):
Yeah, I think I read so much, I know what I like
to read and I know what I don'tand I know what it feels like
when a chapter is like two hourslong and it just feels like a
slog and I went for the shortchapter.
So there's like 88 shortchapters.
Each one has like a beginning,middle and end and then they're
kind of grouped into parts andthose parts of beginning, middle
and end.
So I got some pushback fromsome of the publishers I talked
(42:12):
to.
They wanted like a traditionalintroduction or a traditional
conclusion.
I'm like, oh my God, I'mgetting bored just thinking
about that.
And I had sort of a vision.
I wrote the whole book first,before I even talked to
publishers.
I was like, no, this is what Iwant, we're not doing that.
So I tried to fight the fighton that and I like how it turned
out.
So I'm happy to have done so.
Stephanie Rouse (42:33):
I totally agree with your style choice and I'm
glad Island Press picked it upand saw the vision.
Wes Marshall (42:40):
It makes a big difference when you sort of have
a publisher that's on boardwith that vision.
They didn't push back on someof the footnotes, though they're
like do you really need?
Like to mention the simpsonsagain, I was like do we really
need anything like?
Jennifer Hiatt (42:53):
no, we'll.
Wes Marshall (42:54):
We'll make sure, when we touch base with island
press, to tell them that you didneed those footnotes every
single one of them I literallywrote a book about like kids
dying on the road, right, likeit would be a tough, tough read
if you didn't.
You know, maybe add some levity.
Or you know, also, I'm aacademic, so most of my
writing's been in peer-reviewedjournal papers, right, and you
can't put your personality inthose.
(43:15):
So I was like, well, here's mychance to just do something that
I would read even if I wasn'tin this space, right, and you
know, and if it makes some of myfriends laugh, great, like this
is what I would read, this iswhat I would like.
And it seems like people haveresponded well to it.
So I'm happy to have seen thathappen.
Stephanie Rouse (43:32):
Yeah Well, wes.
Thank you so much for joiningus on Booked on Planning to talk
about your book.
Jennifer Hiatt (43:43):
Killed by a Traffic Engineer.
Thank you both for having me.
This was fun.
We hope you enjoyed thisconversation with author Wes
Marshall on his book Killed by aTraffic Engineer shattering the
delusion that science underliesour transportation system.
You can get your own copythrough the publisher at Island
Press or click the link in theshow notes to take you directly
to our affiliate page.
Remember to subscribe to theshow wherever you listen to
podcasts, and please rate,review and share the show.
Thank you for listening andwe'll talk to you next time on
(44:05):
Booked on Planning.
Thank you.
you're listening to the booked on
planning podcast, a project ofthe nebraska chapter of the
american planning association.
In each episode we dive intohow cities function by talking
with authors on housing,transportation and everything in
between.
Join us as we get Booked onPlanning.
(00:36):
Welcome back, Bookworms, toanother episode of Booked on
Planning.
In this episode we talk withauthor Wes Marshall on his book
Killed by a Traffic Engineer,Shattering the Delusion that
Science Underlies OurTransportation System.
I've had this book on our topreading list for this year's
season and was definitely notdisappointed.
Jennifer Hiatt (00:54):
Stephanie, I know that this has been your
world for a very long time, butI've just recently had to start
learning about transportationplanning and engineering, and
this book was so eye-opening.
I definitely feel betterequipped to have a good
conversation with ourtransportation engineers.
Stephanie Rouse (01:08):
And West does a good job diving into the
history of how traffic manualsdeveloped, their regulations and
recommendations, often taken asthe holy grail but lacking any
real studies or data to backthem up.
It's a great source for thoseof us working in communities
trying to make them more livable, but getting pushback from the
engineers, yeah.
Jennifer Hiatt (01:26):
I have to admit I always thought that you know
well, the engineers know whatthey're doing, so I never really
pushed back.
So now I have a better toolboxwith which to do so in our
conversations now.
So let's get into ourconversation with Wes Marshall
on Killed by a Traffic EngineerShattering the Delusion that
science underlies ourtransportation system.
Stephanie Rouse (01:46):
Well, Wes, thank you for joining us on
Booked on Planning to talk aboutyour book Killed by a Traffic
Engineer.
As a former transportationplanner, this is the book that I
had been waiting so long toactually be able to read.
I'm curious to know how has theengineering community received
your book and have you seen alot of pushback, or are you
seeing kind of light bulbsturning on in the transportation
(02:06):
field, starting to change theway they do business?
Wes Marshall (02:10):
Well, first of all , thanks for having me.
I will say the response fromthe engineering community has
been overwhelmingly positive.
But that doesn't mean therehasn't been some pushback.
And you know, I think thepushback especially has come
just with the title of the book,even though if those folks
actually read the book they'llsee I'm not.
So I've been happy to see someof that pushback because they're
(02:47):
still kind of sticking to theguns that I'm just sort of
dismantling throughout the book.
So I've spoken at some of themajor transportation engineering
conferences, like ITInternational, and nobody
punched me there.
I mean, in fact I think thatwas the first time I was at a
conference where people askedfor my autograph after I spoke.
So that seems a little bitweird, but it was good.
Stephanie Rouse (03:08):
That's good, because Chuck Maron seemed to
have the opposite effect on thetransportation community after
his book came out.
It seems like they startedsuing and really attacking him
instead.
So it's good to hear that thisbook has been received well.
Wes Marshall (03:23):
Yeah, I mean there was one person on the IT forum
asking me to resign and stuff,but again, he hadn't even read
the book and he was just tryingto make sure no one else did too
.
So I think there are some folksthat would rather this book
just go away, but that hasn'tbeen happening, so I've been
happy about that happy aboutthat.
Jennifer Hiatt (03:46):
Well, I'm pleased to report that in
Lincoln we have received wordthat a few of our transportation
engineers, including our deputydirector of what is Lincoln
Transportation Utilities, haveread it and don't seem to want
to punch you.
So that's good.
That's good.
Wes Marshall (03:57):
I have heard that some like state DOTs, like they
try to get in their library andthey've been told no, it's sort
of banned from that.
But those same state DOTs arehaving like secret book clubs
with the books.
So there's promising stuff.
There are a lot of engineersthat felt like I did.
They felt like something waswrong.
They sort of knew what we weredoing often didn't match up with
(04:18):
some of their favorite streetsor favorite cities or favorite
parts of these cities, and theyprobably felt the same
disconnect that I did that ledme down these rabbit holes.
Jennifer Hiatt (04:29):
And traffic engineering is really a newer
profession, even if, you like,say, compared city planning,
which Stephanie and I areplanners.
So that's perspective we'retaking.
So can you give a quick historyof the profession and how it
compares with other forms ofengineering?
I always found the idea that wecall it traffic engineering
kind of interesting.
So is that even the correctprofessional title?
Wes Marshall (04:51):
I mean, the terminology I probably use more
often is transportationengineering.
That's a little bit broader,but it didn't sound as good for
the sake of the title, so that'swhat I went with.
I mean, civil engineering hasbeen around like for thousands
and thousands of years, right,and civil engineering is usually
thought of as structuralengineering, like bridges and
(05:12):
stuff, or hydrology, you knowthings like that.
It's such a broad discipline,like we do environmental
engineering, like we haveconstruction engineering in our
department.
We even have GIS Transportation, like that element of it.
It's only maybe 100 years old,if that.
So that developed with theadvent of the automobile, where
we had this burgeoning need forsome sort of science to wrap
(05:34):
around what we were doing to ourstreets, our cities, in order
to adapt to that new technologyat the time.
So I feel like a lot of usthink this science is so well
entrenched and so well done.
But that's the thing like, whenyou actually start looking at
it it's like, well, no, evenback then we weren't, we knew
that, we weren't there yet.
(05:55):
But you know, we sort of nowthink that it's better than it
is and I will say it's not ourfault, like these thousand page
books that were all given.
I just assumed, as a youngengineer, that whoever wrote
these knew more than I did.
I assumed they did theirresearch.
I assumed that it was steepedin a hundred years of safety
science, and that just turns outnot to be the case.
So yeah, it is a relatively newdiscipline in the grand scheme
(06:18):
of civil or city planning orengineering, or even when you
compare it to things likemedicine.
Stephanie Rouse (06:28):
Yeah, and one of the terms or requirements
that comes out of these manualsthat I don't think has much real
science behind it and is themost frustrating term that I
keep hearing from our trafficengineers is warrants.
And you point out in the bookthat it's really a chicken and
the egg situation, where peoplearen't going to cross a
dangerous road but trafficengineers, based on the manual,
says we we need at least 93people, during peak periods or
whatever, to cross thisdangerous road before we can
(06:49):
actually put a signal in.
So where did this insane systemcome from and how can cities
get around it when theirengineers start citing this?
Wes Marshall (06:57):
Well, you're right , and that's the example I give
in the book is that one type ofstreet where you need 93
pedestrians crossing in the peakhour in order to get the
warrant for a crosswalk.
And you know, my thinking iswell, where does this 93 come
from?
Like, is there a paper theycite, is there some research?
And there isn't.
Like there's nothing behind it.
I mean, I'm sure it's, I guessI hope it's not completely
(07:19):
arbitrary, but there isn't muchwe can base it on.
And then when you think about,well, what does that actually
mean in terms of our design?
You know, I sort of joke likewhat's the best way to fix
pedestrian safety?
Well, we make the streets sounsafe that no pedestrians would
ever use it.
Therefore, we have nopedestrian crashes, but we all
know that's not what we want.
And the same thing goes when wethink about something like this
(07:40):
like, well, how do we make it asafe place to cross?
Well, we need 93 daredevils inthe peak hour to risk their
lives to prove to us that thiscrosswalk is warranted.
So when you just think aboutthe logic behind that, it
doesn't make sense, like there'svery little common sense there.
At the same time, you know,maybe a lot of engineers don't
really know this Like we feel,like especially the MUTCD.
(08:02):
Like you feel like that is themost standard of all our
guidebooks I mean the wordstandard doesn't really fit.
Most of them it's reallyguidebooks, guidelines but in
that case you feel like theMUTCD is kind of the highest
level towards the standard,because we're not going to
obviously do green stop signs orthings like that At the same
time.
When I searched through the book, I counted 167 times, I believe
(08:26):
, where they use the phraseengineering judgment.
Engineers always have leeway touse engineering judgment in
like the exact case you'retalking about.
Like we can say oh look,there's a school nearby.
We don't actually need to have93 people in the peak period
crossing to decide to put in asafer crossing or whatever the
reason might be.
But if you document it, if youhave a very logical, rational
(08:49):
process, you're taking away theliability worries that I think
engineers often have.
So we can use engineeringjudgment, we can use common
sense, but I don't thinkengineers feel empowered to do
so.
Either they don't know theyhave that ability, they don't
know how to do it, or they'reworried about things like
liability issues.
But you can, we can do better,and oftentimes it's a choice or
(09:14):
just not really understandingthat we can.
Jennifer Hiatt (09:16):
Even to the legal side of that.
I'm a lawyer by training,planner by passion, so every
time we would hear one of theengineers be like well, it's a
liability problem.
Like do you have a rationalreason to state why you're okay
with this decision?
Because that's like, that's theminimum legal requirement for
rational basis reviews.
Like can you document therational reason why you're okay?
Wes Marshall (09:39):
putting a crosswalk next to this park
seems like something you couldmeet pretty simply oh, yeah, um,
and we had these fears back inthe late 90s, early 2000s when
traffic calming was sort of new.
A lot of engineers like oh, wecan't do traffic calming, we're
gonna get sued.
And if you look at the researchafter the fact, nobody did,
nobody got sued.
And you know, I lay out theprocess, I call it the rational
(10:01):
process, which is exactly likeyou're describing, and I link it
.
I mean it's sort of liketactical urbanism, right, we
know we have a problem and wecan document that problem with
data, like, let's say, it'sspeeding.
If we have speeding data and weknow we're trying to fix this
speeding problem, and we come upwith a list of viable
alternatives, right, and we pickone that we think works best.
(10:21):
And then we collect data to seeif we're actually fixing the
problem we'd laid out.
You're protected from liability.
I mean, engineers historicallywill just throw up a sign, say
like even like a sign that saysdangerous intersection ahead,
and when you first see those,you're like what the heck are we
doing?
Like, why don't we just fix thedangerous intersection?
But when you step back it'slike well, why would you do that
?
And it's because of liability.
(10:42):
If you just warn people, itdoesn't fix the problem by any
means, but it alleviates theliability concern.
I'd rather see us be much moreproactive and start trying to do
stuff that may or may not be inthe manual, because we know we
have these problems.
They're known, we can documentit, we can get data on it and
let's do better.
Jennifer Hiatt (11:01):
I agree.
One of the things that I couldnot get over reading this book
because I am not atransportation planner by any
means is that traffic engineersoften treat a fatal collision
the same as a fender bender forcounts and whatever, and that's
been influencing our road designfor years.
Can you explain why we've beendoing this?
Wes Marshall (11:21):
Yeah, I mean, well , there's these, you know, from
the 1920s or all theseindustrial accident research.
They would have this pyramidand the idea is basically that
crashes are proportional interms of severity.
So if you just count, the totalnumber of crashes including
fender benders, like that'll beproportional to minor injury,
major injury, severe injury allthe way up to fatal.
(11:43):
So we don't really need to justfocus on the fatals.
I mean, we'll get the sameanswer no matter which level we
focus on.
And it might be true inindustrial accidents, but when
we translated that totransportation and we made those
assumptions that it was true,it turns out not to be the case.
I mean, I think you all knowthat when you look around cities
, like some of the densestplaces, you have such slow
(12:04):
speeds and you have a lot of,maybe, traffic congestion, so
you have a lot of fender benders, right, but that's not where
people are dying on our streets.
It's where you know thefundamental physics of it, like
you need speed, mass and that'swhat gives us the force and end
up having people lose theirlives.
So you often get completelydifferent answers Like our
highways don't have many fenderbenders, but that's where you
(12:25):
have a lot of fatal crashes andvice versa, in cities where you
have a lot of fender benders butnot many fatalities.
So if we made the mistake ofassuming that safety is just
based on fender benders, youstart taking these rural or
highway type designs and pushingthem through cities and that's
where you start gettingfatalities there, because we've
(12:46):
conflated the problem.
Jennifer Hiatt (12:48):
I find it interesting too, though we had a
very bad intersection here inLincoln.
People were somewhat regularlydying at this intersection.
Then we put in roundabout andmore accidents happened, but
nobody died.
Some of our residents were like, but more accidents are
happening here.
This is ridiculous, butnobody's dying.
People were dying.
(13:09):
You can't win for losing inyour profession, really.
Wes Marshall (13:12):
No, it's a matter of priorities.
I think I named that chapter.
Don't sweat the small stuff,and the small stuff is fender
benders.
That's a concern for insurancecompanies.
It's annoying and all, and wecan improve that too.
But let's start with whatactually matters are people's
lives, and, for whatever reason,we treat road safety,
especially things like liveslost on the road, as the cost of
(13:35):
doing business, as opposed tolike the public health emergency
that it really is.
Stephanie Rouse (13:39):
Yeah, it's really interesting on crashes
how we treat them based on typeof mode.
So we just accept the very highrates of traffic deaths on our
roads every year, but one planewith a couple hundred people
goes down and there are so manymore investigations and it's all
over the news, but no one'sreally talking about the massive
(13:59):
lives lost on roadways everyday.
Wes Marshall (14:01):
The massive lives lost on roadways every day.
That's funny.
My safety class this weekthat's exactly what we talked
about.
I was trying to teach aboutexposure, like the idea that we
can't just look at total numberof crashes or fatalities, and
it's not really apples to apples.
You want to normalize it bysomething, and we talked through
, we tried to actually calculatehow safe it is to be in a
(14:22):
commercial airline or how safeit is to be on a train versus
how safe it is to be in a car,and I think we found the plane
was 121 times safer than a carper mile and the train was
something like 40 or 50 timessafer than a car.
But then we talked aboutexactly what you said, even when
the Boeing door stuff was anational issue.
(14:44):
Right, this was something thateverybody was up in arms with.
Pete Buttigieg was out theretalking about it, or we had some
train crashes, I think, like inIndiana or something.
I mean same thing, but at thesame time every night you turn
on the news like somebody diesin a car crash and it barely
makes a headline and far morepeople are dying on our roads
and car crashes and pedestriansand bicyclists than die in
(15:08):
planes and trains, but forwhatever reason, we don't treat
it at all in the same way andpart of it.
You know sort of the differencebetween like a dripping faucet
and like a fire hose.
Right, when a plane goes down,it's like 200 people and, yeah,
it makes perfect sense why wewant to fix that.
But even when more than 200people die in a single day on
the roads, it doesn't feel thatway Now.
So even around the world like,if you look at the numbers, more
(15:28):
people die every day on theroads than died in 9-11, but
we're not really doing muchabout it.
I saw TRB put out a reportearlier this week.
The graph shows fatalitiesgoing up, but fatalities per
like vehicle mile travel aregoing down, and the caption said
that roads are safer than ever.
I'm like, wait a second,they're not.
More people are dying.
(15:49):
How is that safer than ever?
It's because they're measuringthe wrong thing.
Stephanie Rouse (15:54):
We track annually progress on our
comprehensive plan and one ofthe metrics is vehicle miles
traveled and crashes per vehiclemiles traveled.
And after reading that sectionI was like, oh, maybe we should
stop showing that, becausethat's not really helpful.
Wes Marshall (16:08):
Well, it's helpful if you're looking at the safety
, maybe, of a particular road orintersection, right, and you're
comparing, like that facility,but it's not helpful for us
humans, right?
You care about it much morelike any other public health
measure, and every other publichealth measure is a per
population metric.
You know, for a while I waslike man.
Us traffic engineers werepretty dumb to do that and
(16:30):
that's one of the you know, oneof the rabbit holes I dug down
and I found out that you know,sometimes, like we admitted that
we didn't know enough and we'retrying to get better, but that
is one where it's literally.
The CEO of Studebaker didn'tlike in the 1930s, how cars are
being made to look very unsafe,so he made the right point that
we need an exposure metric, buthe just picked the one he liked
best.
(16:50):
He wrote a book about it.
This textbook right behind me,seven Rows to Safety, paul
Hoffman, in 1939.
And he came up with a metric ofmeasuring it per vehicle mile
travel.
And then he barnstormed thecountry selling this new metric
to this brand new discipline oftraffic engineering.
We started using it and 1966 or65, the USDOT put this into
(17:14):
their official metrics formeasuring traffic safety, and
we've been doing it that wayever since, but at the same time
, when you think about what thatactually means, there's two
ways to improve safety.
One is we reduce fatalities orsevere injuries.
The other way is to increasedriving.
The more you drive, the saferyou seem, and we've been
building our transportationsystem in the streets based on
(17:35):
the latter.
Stephanie Rouse (17:36):
And so that's one of the examples of we've
just been doing this way forever.
We keep talking about bad datagoing into some of these manuals
this way forever.
We keep talking about bad datagoing into some of these manuals
and some of them take foreverto update.
The MUTCD was this very longdrawn-out process back and forth
negotiations, good changesgetting cut.
Why is it so hard to changethese manuals when we know
they're not accurate?
Wes Marshall (17:57):
Well, inertia is one of them, part of them.
There's a lot of vestedinterest in sort of keeping the
status quo, not just intransportation but in sort of
everything.
So there's some entrenchedfolks on these things.
But I don't know, like theMUTCD I'm sure you saw, you know
there was that public commentperiod and do you remember how
many wasn't there, like 10,000or something crazy like that?
(18:18):
Yeah, it was high, yeah, andthere's some improvements in the
latest version that you knowstill yet to be adopted by all
the states, but it's still notwhat we need or want.
And that's the case with all.
I mean the Ashford Green Bookand a lot of the other ones.
The Highway Capacity Manualthey're similar.
Like you know, I was actuallyjust invited yesterday to speak
at the TRB, the TransformationResearch Board.
(18:39):
We have a giant conference inDC or like 15,000 people there
and the committee that looks atcapacity they're the ones that
are helping write the highwaycapacity manual.
They want me to come speakabout.
I mean the fact that level ofservice isn't this thing handed
down to us on Mount Sinai, toMoses from God.
It was sort of haphazardlythrown together in a meeting,
(19:02):
just like the meeting we'regoing to have in DC in January
where, like some guy over hereis like, oh, we need to do this.
And they're like, oh, in thefuture, we need to make sure we
add safety to this.
And then the next iteration weremove that sentence.
We never added safety.
And so when you see how itactually came together, I think
a lot of engineers it sort ofblows their mind that oh, this
wasn't this very rigorousscientific process.
(19:22):
This was a meeting just likethe one we're in, where people
are negotiating for what theythink is best for the time being
.
Jennifer Hiatt (19:31):
Well, and to that end, so many of these
manuals were new to me as I wasreading about them, so I had to
look them up and read about themin our book, and it seemed that
each manual oversteps itspurpose in many ways.
So, for example, in the bookyou say that the MUTCD is
supposed to provide standardsfor traffic signs, signals and
markings, but it also feels theneed to add its two cents on
setting speed limits, forwhatever reason.
(19:52):
Doesn't this ultimately createa confusing situation and make
it difficult to apply standardsacross the board?
Wes Marshall (19:58):
Well, the whole idea behind these from the get
go was that, especially in theUnited States States, where
things can differ from state tostate, like we need some
reciprocity, we need somesimilarities when you go from
one state to the other.
I mean stoplights shouldn'tflip or stop signs shouldn't
look there, all that sort ofstuff Like we need to have a
commonality.
So that was the idea behindthem.
But you know, over time, youknow maybe there's some bloat,
(20:21):
maybe there's some.
You know, maybe there's somebloat, maybe there's some.
You know group think, like youknow you've been in meetings and
there's a lot of people likeit's easier to kind of pick what
you think is the safe option asopposed to maybe picking the
right option and transportation.
I think this is tricky becausea lot of the stuff that happens
is very counterintuitive.
So our theory, you knowsomething basic, like wider
roads are safer because it givespeople a factor of safety.
(20:43):
Um, if you're speeding, ifyou're drunk or something,
you'll still have space to runoff the road and you're going to
live, and that makes perfectsense.
Maybe if you're a structuralengineer or if you're someone
designing a culvert, motherNature doesn't care how big I
make the beam on this building.
It's not going to be anywindier, it's not going to rain
anymore, so the culvert could bebigger, the beam could be
bigger, the beam could be bigger.
But in transportation peoplebehave based on the
(21:05):
transportation system you put infront of them.
So, yes, the theory makes sense, give people more space.
But if they start going faster,or maybe not paying as close
attention to the road or theside of the road, or they look
at their phone longer, whateverit might be, I mean, the
empirical results aren'tmatching the theory.
And you would think in ascientific discipline we'd fix
that, we would learn, we'd getbetter we.
(21:26):
But for some of the reasons youtalked about in the question is
like we haven't.
Like we, that group, think thefact these manuals have been
around for so long, the factthat we think they're based in
science, has kept us maybe fromchanging them, from pushing
forward, from trying to makethem better, and hopefully, what
my book points out is they'renot as scientific as any of us
were led to believe.
So we don't need to hold ontothem as dearly as we think.
Stephanie Rouse (21:50):
Yeah, and knowing that we're probably not
updating the METCD anytimesooner, hopefully that gives
engineers more license to useengineering judgment, which is
actually built into the manualto use.
Wes Marshall (22:01):
I hope so.
I mean, I know this book is notspecifically meant for traffic
engineers.
I hope they read it.
I hope they do better.
But I also want to give peoplein positions like you, or
advocates or people like that,enough ammunition to maybe more
effectively argue with anengineer, like I've heard you
all in your podcasts complainabout.
You put these great planstogether and then where do you
(22:22):
get your pushback right?
So often not even from thepublic is from the engineer Like
oh, that looks great, but wecan't actually do that.
So you know you get enoughinformation from my book where
like oh, like what he's actuallysaying there, what she's saying
there isn't really a standard.
Like they do have engineeringjudgment and you can point this
out to them even if they don'tread the book.
But I'm glad to hear they did.
Stephanie Rouse (22:43):
Yeah, we'll definitely pull in some sections
and forward them on the nexttime they push back on our ideas
.
So no discussion oftransportation is going to be
complete without addressingautonomous vehicles, and you
rightly point out in the bookthat this isn't the silver
bullet that's going to fixeverything.
Even if we could get everyoneinto an autonomous vehicle and I
hadn't really thought of it too, about just beyond the
(23:05):
affordability piece there'sgoing to be people out there
that don't trust this technologyand will never adopt it, and so
we're never going to geteveryone in autonomous vehicles.
So there's still going to beplenty of us with our own
autonomy in a vehicle or walkingor biking.
What are some of the other redflags with this reliance on
autonomous vehicles that youdiscuss in the book?
Wes Marshall (23:25):
I think if you look at the benefits of
autonomous vehicles, you knowthe thinking is like human error
is a big problem in our crashes.
It's like 90, they blame it on94%, but that's something I sort
of disprove in the book too andthat we're going to get all
these benefits within thisautonomous system.
So we're not going to needparking, we're not going to need
whatever it is.
We get all the benefits.
(23:46):
But if you look at that list ofbenefits, you only really get
them if every car on the road isautonomous.
I remember I was in Australiafor sabbaticals, I was in Sydney
and they used to do this thingcalled city talks and they
brought in these outsidespeakers, which were great and
hundreds of people came to this.
And I saw one by this guy fromMIT and he was showing this
awesome animation of, like thisconventional intersection where
(24:09):
delay is happening, cars arebacking up, and he showed an
autonomous intersection whereevery car is getting a
reservation and just flyingthrough this intersection like
crazy.
And he declared the latter onethe future of urbanism and he
got the standing ovation fromlike 200 people.
I'm like wait, what?
Like what if you have one humandriver or one pedestrian or one
(24:30):
bicyclist.
Like that doesn't workwhatsoever.
Like this might be the futureof the middle of nowhere, but it
is not the future of cities.
And when you start thinkingabout even if we can get the
technology right, like yes,waymo's ahead of other folks and
doing the robo taxis in SanFrancisco and places, but you
don't get the same benefits whenit's just a few of them, and
(24:50):
how can we get everyone to do it?
I mean, you know, I joke thatthere's a reason why there's
like 11 Fast and the Furiousmovies and they've made like $10
million or whatever it isbecause people love driving and
there's a huge culture around it.
So to get everyone to shiftisn't often just the technology
problem, it's a social orcultural problem and it might
(25:13):
not go as far as like the gundebate goes, but you're going to
have some people saying you'regoing to pull this steering
wheel out of my cold dead handsand like we're not going to get
there right.
So there's so much behind it.
And then, if you, I read PeterNorton's great book Autonomorama
recently and like he basicallybrought this back you know 50,
60 years where we've had thistechnological carrot kind of
(25:36):
dangling in front of us, andit's always five years in front
of us and it's been five yearsin front of us for 60 years and
it's still there.
It changes what that technologyis, but it's still hanging in
front of us.
And it's been five years infront of us for 60 years and
it's still there.
It changes what that technologyis, but it's still hanging in
front of us.
So there's a lot of people Iknow that are great engineers
but they just don't really worryabout safety because they feel
like AVs will fix it.
And it's just not true.
It's easier said than done.
(25:58):
It's much more complicated interms of the social, cultural
than we think.
Even if we get the technologyright, yes, we'll reduce some
types of crashes, but with everytechnology over the course of
history it leads to other typesof errors.
So I mean, just interactingwith these different
technologies isn't the same.
10 years ago I remember drivingup to the mountains with a
(26:20):
neighbor of mine.
So I live in Denver and if youwant to go skiing or
snowboarding, go an hour pluswest.
Then there's tons of snow andtons of that kind of stuff.
And at the time I think he hada new BMW and he was just
changing lanes willy nillywithout looking.
I'm like man, what are youdoing?
Shouldn't you look?
He's like oh no, the car willtell me if there's a car in the
adjacent lane.
So if he added that technologyto what he had done before, if
(26:43):
he was still looking over hisshoulder and using the mirrors,
and you layer that technology ontop, it would be safer.
But when you replace thetechnology, maybe not.
Our cars get dusty in themountains, so maybe it's not
working or maybe the sun is acertain glare.
The technology can't see thatcar, whatever it might be.
The safety benefit isn't asclear cut when you think about
(27:05):
it this way.
And even those cars now thatare supposed to stop for
pedestrian I mean, the researchshows they don't work in certain
lights.
They don't work as well withdarker skin.
You know these technologies arekind of a little bit racist
when you think about it that wayand we don't want that either.
So if we start shifting how webehave based on technology and
this relates to the last pointswe were talking about it's not
(27:27):
as clear-cut.
Jennifer Hiatt (27:28):
So it's, it's just not that simple every time
I read about technology that'ssupposed to be able to like
identify people and how it justhardly ever identifies people
with dark skin.
I think about the episode fromthe tv show better off dead.
If you haven't seen it,everybody should go.
Watch's funny.
Got canceled after like twoseasons, but they have a whole
episode where it's like the costbenefit of putting in all of
(27:49):
this automated stuff versus theuncomfortableness of their
employees of color.
It's like they couldn't washtheir hands, lights didn't turn
on, cars don't stop for them.
This seems like a bad future.
Plus, I've seen too manydystopian movies and read too
many dystopian books.
You're not putting me in an AVcar.
Wes Marshall (28:06):
Yes, my wife watched that show.
That's the one on Netflix.
It starts off, didn't it?
Like the friend's husband diedin a crash, or something like
that I saw a couple of thoseyeah.
Jennifer Hiatt (28:14):
Speaking of cars , I know transportation
engineers don't design cars, butshouldn't you guys have maybe
(28:37):
some kind of say in that.
Wes Marshall (28:38):
So we create roads you can drive 120 miles per
hour on.
But why does any car reach 120miles an hour when nowhere in
the country has a speed limitover 90?
It doesn't make sense.
I do have some chapters aboutcars and how fast and big they
are, and you know I joke.
When I was 16 and I boughtmyself a car, I was pretty
thankful it couldn't go morethan like 75 or 80, because it
was a pretty crappy car, becauseat that time I drove as sort of
fast as I could everywhere Iwent.
And now if you look at theodometers on a lot of cars
they're like 140, 160, 180.
(28:59):
I've seen a sum of 220 and 240.
We don't need that unlessyou're like driving NASCAR or
Formula One.
But there is, for whateverreason, like thinking that more
power equals like more safety.
I mean there's also social,cultural issues.
You know, talking about theFast and the Fur came to Denver
(29:22):
like people were crazed abouthow fast they go and try to do
some geofencing around, like our16th Street Mall, which is a
pedestrian zone, to make surethese scooters were forced to
drop down to three miles an hourin that zone.
I know DC does somethingsimilar.
They couldn't get it to workhere in Denver but for whatever
reason, everyone was okay withthat.
But when you say the same thingabout cars, people lose their
(29:44):
mind.
Like oh, that's un-American,like you can't tell people what
to do and I know, for whateverreason.
With things like even red lightcameras, speed, the
conversation devolves intofreedom.
Big brothers watching me Likethe conversation is never about
safety.
If we can keep the conversationon safety, we'd be better off.
You know, if safety really wasour first priority, our cars
(30:04):
would be bubble wrapped.
They would go no more thanmaybe 20 miles an hour in cities
.
But it's not.
You know there's a group ofpeople that are trying to make
money off of cars, but we'vealso built a transportation
system where most people live ina place where driving is really
the only viable option.
And then when you think aboutthe rational decision of those
folks, like driving in a big SUVmakes the most sense too right,
(30:24):
and to me I feel like it's onengineers to fix that, on
transportation planners and cityplanners to fix that.
At the same time, there is arule for policy in terms of
limiting speeds or limiting carsize, or even just making folks
that use a bigger, badder carpay more in insurance right.
Use a bigger, badder car, paymore in insurance, right.
Like there is more risk thatyou're putting out there into
(30:45):
the world when you drive a trucklike that than if you drive
like a Mini.
Cooper or something right that'snot anywhere embedded into,
like the costs that are put onto folks that do that.
Stephanie Rouse (30:57):
When you're talking about, if we really want
things to be safe, we wouldn'tbe driving more than like 20
miles an hour.
And it was really interesting.
I had friends from Minneapoliscome in last weekend and when
they got there they were like,oh, is it 35 miles an hour on
your street?
And it's kind of a sort ofresidential, but it's
technically like a collectorstreet in Lincoln, but it feels
more like a residential street.
And I was like yeah, no, it's35.
(31:18):
And they're like, oh, that'sweird, it's 25 everywhere in
Minneapolis now.
And I was like, yeah, no, wehave streets that run through
town that are 45 miles an hour,like we are not really
prioritizing safety in ourcommunity, like Minneapolis and
some other communities are.
Wes Marshall (31:33):
Yeah, I mean, if you look at the data, you know.
I mean there's a lot ofdifferent numbers that look at
it, but in general, like apedestrian that gets hit at 20
miles per hour, it's maybe a 15%chance of dying.
At 30 miles an hour it's closerto 45%.
At 40 miles an hour it's like80, 85%, right?
If you just know those numbersand if you say safety is our
(31:54):
first priority, it's obviouswhat to do.
But we're not doing that inmost places.
Jennifer Hiatt (32:00):
I think the diagram was in your book or it
was in some extra research I wasdoing to do, but we're not
doing that in most places.
I think the diagram was in yourbook or it was in some extra
research I was doing to prepare,but it showed like a big truck
and a car and the impact zone ona human body and I am five foot
tall and never really thoughtabout like where a car would hit
me if I got hit and that waslike a terrifying realization
(32:20):
that my head isn't even in likea sight line of maybe half of
the cars that people sell thesedays or buy or drive.
Wes Marshall (32:27):
Oh yeah, I've seen some.
I don't have any images in mybook whatsoever, so there
probably wasn't one you sawthere, but I talk about that
exact issue, right?
So if you are hit by like aHonda Civic from 20 years ago,
you get hit in the legs, youroll up into the hood, you may
hit the windshield, you mightbreak your legs, but you're
often going to be okay.
If you get hit by an SUV today,you get hit like in the chest,
(32:47):
you get knocked down, your headhits the pavement and you get
run over and you're much morelikely to die.
I'm doing a talk at the SafeRoutes for School conference in
a couple of weeks and, like oneof the things I'm thinking about
is I mean just the fact thatlike even something design-wise
as simple as where we put thestop bar in front of like a stop
sign, like you know you knowthere's a lot of videos on this
(33:09):
like in a lot of our SUVs today,like there's that one from
Indianapolis where they had 13kids sit down in front of that
car and the driver couldn't seeany of them, right?
Well, how would you design theintersection differently?
Well, you should push the stopbar back like 20 feet, right?
If our car is going to be thisbig, if kids are this little,
let's design this differentlyand daylight the intersection,
push the stop bar back.
(33:30):
There's simple, obvious, commonsense things to do, but we're
not doing them.
Stephanie Rouse (33:35):
So another term that comes from the manuals
that deals with speeding is the85th percentile another one of
my least favorite terms I keephearing from our engineers.
So the concept is you know, wematch our speed limit based on
what 85% of the drivers aregoing, then the drivers take
that speed limit and up theirspeeds, and then it's just this
continuous cycle of raisingspeed limits.
(33:57):
Why is it so hard for engineersto just design a street for
lower speeds, that they actuallywant to see an action, versus
waiting for drivers to drive aspeed and then adjusting?
Wes Marshall (34:07):
Well, this is a good example of the theory kind
of trumping empirical results.
We have this theory that aslong as all drivers are in the
same maybe 10 mile an hour pace,like most of our drivers are in
that same short pace, that'show we, like most of our drivers
are in that same short pace.
That's how we get to safety.
It doesn't matter if that paceis 80 or 20, safety is better,
(34:28):
right, and that research goesback to David Solomon, like this
older research when you look atthe original study that led us
to think that it's been debunkedhalf a dozen times over, based
on just these rural roads inTexas, and he showed something
that, like these slower cars arehundreds of times more
dangerous than the faster cars,and it just wasn't true.
(34:50):
If you dig into the actual data, it's really just people
turning in and out, of, like gasstations on these rural roads
that are getting hit from behindby the faster cars.
And all the empirical resultssince then shows us that higher
speeds leads not only just tomore crashes but worse overall
safety in terms of fatalitiesand severe injuries.
But that thinking has stuck andwe have this mantra if you look
(35:11):
at, like in the MUTCD, how weset speed limits.
It's based on the assumptionsthat drivers are reasonable and
prudent.
Whatever road you put in frontof them, they'll tell us how
fast and safe to drive.
Like is that true?
Do you feel that's true?
Probably not, but that's stillwhat we're doing.
So we let drivers vote withtheir feet as to how fast the
speed limit should be.
And I mean, I give some crazyexamples in the book, like
(35:33):
there's one from Californiawhere these college students at
Cal State Northridge were killedon the road right next to it as
pedestrians.
And you know, like, oh, we gotto do something about safety.
So what do they do?
They did a safety study, theydid a speed study and they
raised the speed limit.
It's like, wait what?
We raised the speed limit onthis road next to a college
because a pedestrian was killed.
And that's how you're going tofix safety.
(35:53):
And guess what?
More pedestrians were killedand they did it again.
And it just doesn't make anylogical sense.
And there's the other examplefrom Utah, where they had this
problem with wrong-way driverson their highways and their
thinking of how to fix thatsafety problem was to do a speed
study and raise the speed limit.
It's like how in the worldwould that possibly fix this
wrong-way driver problem?
(36:14):
But that's the thinking is thatthis 85th percentile is the way
to safety, and it's just nottrue and the research doesn't
back it up.
But we were taught that this ishow we get safety, so that's
why we're still doing it.
Jennifer Hiatt (36:29):
Bothers me.
Wes Marshall (36:30):
It should.
That's the thing, right.
It bothers me and that's why Iprobably a tinge of anger in a
lot of my writing, because I'mangry about some of this stuff,
right.
Stephanie Rouse (36:42):
So a lot of it came through in your footnotes
and I loved all of thereferences and the snarky
comments.
I never read footnotes, butthose ones I definitely did.
Wes Marshall (36:49):
Thank you, it was good to hear.
Jennifer Hiatt (36:51):
Never skip the footnotes.
So, as you mentioned at the topof the episode, though, at the
end of the day, you're notactually saying that
transportation engineers areintentionally designing bad
roads or actually going out oftheir way to try and kill people
.
So, ultimately, what steps areyou proposing?
The profession needs to startdoing better for our cities and
people who live in them.
Wes Marshall (37:10):
So I link it to medicine and doctors.
Right, doctors have been aroundfor similar to civil
engineering like 5,000 years,let's say, and it wouldn't be
hard to say, you know, the firstthousand years after
Hippocrates.
Let's say, and it wouldn't behard to say, you know the first
thousand years after Hippocrates, that they were probably
killing more people than theysaved.
But it's an empirical science,they were getting better, they
were learning, they're doingtrials, whatever have you in the
(37:31):
medicine world, and now I meanit's not perfect, but they're
still trying to get better andbetter.
Like that's the thinkingTraffic engineering,
transportation, engineering.
We're only 100 years old andwhat I'm saying is we're still
in that stage, like we're stillkilling more people than we save
.
We just don't know it.
And our problem is we havebecome less of an empirical
science.
(37:51):
Like we're still steeped inthese theories that have been
disproven and to some extent itfeels more like a religion than
a science.
So how do we get better?
We need to go back to being ascience, get back to being an
empirical science.
Do things like the rationalmethod or tactical urbanism.
See what works, test stuff, useengineering judgment and learn
(38:14):
and get better.
And look around at the cities,the streets that work.
I know I grew up right nearBoston and that's what kind of
led me down some of these pathsis the stuff I was building as a
consultant, you know, worked aslike seven years in that space
was never as good as what I sawaround me.
I was like, well, why can't webuild a street like that?
And you look it's like, well,it's illegal to given, you know,
(38:38):
certain guidelines or certainparking minimums or level of
service, and these are ourfavorite places and cities that
we have engineered out of beinga possibility.
Then we look at, well, where dowe put most of our engineering?
Like in most cities, thearterial network that the DOTs
(38:58):
are often in charge of are ourmost engineered roadways.
That's where we put all of ourscience and thinking.
And then you look every citythat's done one of those high
injury network studies where 50or 60% of deaths take place in
like 5 or 6% of the roadway.
Which roadways are we lookingat with that?
It tends to be those samearterial roadways where we put
(39:21):
all of our engineering thinkinginto, and you see the disconnect
.
It's not hard to see it.
So that's what we need to startdoing is getting back to being
an empirical science, gettingback to actually looking around
and seeing, well, what works.
What is maybe the corner radiiof this street that we all love
and it works today?
What is actually thatmeasurement?
(39:42):
And you see, well, we can'teven build that today.
Well, maybe we should change.
What we can build today andthat is where I hope it starts
going is more in that, empiricalas opposed to theory-based
direction.
Stephanie Rouse (39:54):
I would love to see that as well.
And, as this is booked onplanning, what books, in
addition to yours, which we allrecommend everyone, of course
check out that you wouldrecommend our readers read?
Wes Marshall (40:05):
Yeah it's funny, while I wrote the book for like
the three plus years there, Ididn't read any of the
transportation books.
I didn't want to be influencedby the other books that were
coming out.
So I kind of went in my caveand did my stuff During that
time.
I read a lot of fiction andstuff, but not anything
(40:25):
transportation.
I actually stopped listening toeven the smart podcasts.
I only listened to really dumbpodcasts for a few years in
there.
When I came out of the cave Istarted trying to catch up with
everything.
So I know some of these authorshave been on your show, like
Angie Schmidt and like DanPiakowski and Jeff Spex, like
his new Walkable Cities book,human Transit by Jared Walker,
the second edition I just readrecently the ones I was
(40:46):
surprised how much I loved.
I just read Anna Ziver's whenDriving is Not an Option and
Veronica Davis I think you hadon your show too Her Inclusive
Transportation.
I loved that book.
Going back in time, like someof the, I first got into this
world, like Donald Shoup's workwas always.
I started getting into thateven before his High Cost of
Free Parking book came out andyou can maybe see some of his
(41:07):
same approach.
They're kind of shedding lighton the lack of science behind
parking.
That I do with a lot of otherthings Transit, metropolis, the
Robert Severo book from like thelate 90s, I think.
There's so many books out there.
I'm actually curious more whatyou guys are reading these days.
Stephanie Rouse (41:24):
You can see what we're reading on our show
Two books.
We're kind of getting into agroove of two books a month
which is hard to read, much elsethan what ends up on this
podcast.
Wes Marshall (41:32):
Yeah, I'm sorry.
My book was like 400 pages.
That makes it harder.
Stephanie Rouse (41:36):
It was a pretty good read, though Just the way
you wrote it made it digestible.
Jennifer Hiatt (41:42):
I was going to say it went very quickly.
When you pick it up it lookshefty, but when you start
reading through it it's verysimple to get through.
Like so I can study easier todigest.
Wes Marshall (41:50):
Yeah, I think I read so much, I know what I like
to read and I know what I don'tand I know what it feels like
when a chapter is like two hourslong and it just feels like a
slog and I went for the shortchapter.
So there's like 88 shortchapters.
Each one has like a beginning,middle and end and then they're
kind of grouped into parts andthose parts of beginning, middle
and end.
So I got some pushback fromsome of the publishers I talked
(42:12):
to.
They wanted like a traditionalintroduction or a traditional
conclusion.
I'm like, oh my God, I'mgetting bored just thinking
about that.
And I had sort of a vision.
I wrote the whole book first,before I even talked to
publishers.
I was like, no, this is what Iwant, we're not doing that.
So I tried to fight the fighton that and I like how it turned
out.
So I'm happy to have done so.
Stephanie Rouse (42:33):
I totally agree with your style choice and I'm
glad Island Press picked it upand saw the vision.
Wes Marshall (42:40):
It makes a big difference when you sort of have
a publisher that's on boardwith that vision.
They didn't push back on someof the footnotes, though they're
like do you really need?
Like to mention the simpsonsagain, I was like do we really
need anything like?
Jennifer Hiatt (42:53):
no, we'll.
Wes Marshall (42:54):
We'll make sure, when we touch base with island
press, to tell them that you didneed those footnotes every
single one of them I literallywrote a book about like kids
dying on the road, right, likeit would be a tough, tough read
if you didn't.
You know, maybe add some levity.
Or you know, also, I'm aacademic, so most of my
writing's been in peer-reviewedjournal papers, right, and you
can't put your personality inthose.
(43:15):
So I was like, well, here's mychance to just do something that
I would read even if I wasn'tin this space, right, and you
know, and if it makes some of myfriends laugh, great, like this
is what I would read, this iswhat I would like.
And it seems like people haveresponded well to it.
So I'm happy to have seen thathappen.
Stephanie Rouse (43:32):
Yeah Well, wes.
Thank you so much for joiningus on Booked on Planning to talk
about your book.
Jennifer Hiatt (43:43):
Killed by a Traffic Engineer.
Thank you both for having me.
This was fun.
We hope you enjoyed thisconversation with author Wes
Marshall on his book Killed by aTraffic Engineer shattering the
delusion that science underliesour transportation system.
You can get your own copythrough the publisher at Island
Press or click the link in theshow notes to take you directly
to our affiliate page.
Remember to subscribe to theshow wherever you listen to
podcasts, and please rate,review and share the show.
Thank you for listening andwe'll talk to you next time on
(44:05):
Booked on Planning.
Thank you.
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