Louisville streets provided the first evidence-based research of the problem of traffic on neighborhood
streets.
It provided the foundational arguments for traffic calming.
Donald Applyard, who was a professor, conducted a series of studies on three different streets
in San Francisco, chosen to be as identical as possible in every dimension except for
one, the amount of traffic on each street.
And what Donald Applyard was able to show, that just the mere presence of cars with the
envelope of danger that they project around them and the noise and the pollution, crushes
the quality of life in our neighborhoods.
What's really interesting about the graphics in Louisville streets and what they really
provided was it removed us from just looking at specific numbers of people being hit or
killed on streets, but actually showing that there was this other way that we could measure
the environmental impacts of traffic on neighborhood streets.
Things such as a light traffic street helped knit a community together and, in contrast,
a heavily trafficked street would actually rip it apart and fewer social ties were able
to be created.
This chart here shows the social interaction on these three different streets.
So each line shows a connection between one person on the street and another.
There are just a lot fewer lines on the heavily trafficked street as opposed to the moderate
or the light traffic street, which clearly has a lot more interconnection.
So what these charts are showing is that people on the light traffic street know more people
have more friends than on the heavily trafficked street.
On the light traffic street, people have, on average, three friends per person.
And on the heavily trafficked street, 0.9 friends per person.
The fact that the amount of traffic on the street on which you live can impact the number
of friends you have in the world is of enormous significance.
The other thing that Donald Appleyard plotted on these charts are these little dots that
indicate where people gather.
So it shows on the heavily trafficked street there are a much smaller number of dots and
there are only a handful of places where people would gather on their street.
The fact that they were able to measure and quantify the reduction in number of friends
in number of acquaintances that's caused by traffic is enormously important and helps
to illuminate the invisible harm that's done by traffic every day.
Also his graphics showing the extent of one's home territory were incredibly important in
helping people understand that the nuisance of traffic, the threat to our safety, the noise,
the pollution, that really had a diminishing effect on what we felt was part of our neighborhood
or our home territory.
And what we have plotted here are people's responses on the three different streets,
the heavily trafficked street, the moderately trafficked street, and the lightly trafficked
street.
And so it's probably easiest to understand these charts on the heavily trafficked street
because people basically drew red rectangles which shows their apartment or in some case
their whole building as being their home territory.
So people defined their home territory as just the individual space in which they lived
or maybe the building.
If you look on the lightly trafficked street, you start to see that most of the people are
defining their entire street as their home territory with some people saying their building
are a slightly larger area.
When you get to the moderately trafficked street, some people still said it was just
their apartment.
You had more people saying it was their whole building and then you had a few people who
defined territories as being their whole street.
These invisible harms are things that people need to be aware of.
They need to be conscious of when they drive so they're aware of how their driving affects
the people around them.
At the basic level, a Louisville street is one that feels comfortable to you.
It's one that gives you energy.
So an Louisville street is one that you want to escape from and the important part of the
research was that it actually showed those senses that we have about our street environment.
Another part of the survey that Donald Appleyard conducted with residents on these streets
was he gave them a blank map of their street and asked them to draw their street.
And what he's produced here are composite pictures indicating how many times each feature
was drawn.
What this shows is that on the heavily trafficked street, they just drew the entirety of the
street with very little in the way of details.
As you start getting to the moderately trafficked street, people start drawing more details about
the specific buildings and when you get to the lightly trafficked street, people start
including details of buildings, plantings, things like that, that people just know their
street a lot better when they picture it in their head.
They can picture lots of details, lots of nuances.
These studies were the first piece of academic research in the United States to document
the social harm that is done by traffic.
Auto ownership in this country has grown threefold since Livable Streets was first published.
So traffic conflict and incursion on neighborhoods is still a major issue we need to deal with.
Thank you.
