Bending The Culture Curve

There's been a lot of news since the last post about complete streets and safety at this site.

Traverse City leaders are making traffic safety a priority and released a Bicycle Safety Rules PDF.

Also See IPR: Bike-Car Crashes Concern City Leaders In T.C.

There was a study released on the most dangerous cities for pedestrians in the U.S.
See NYT: On Wide Florida Roads, Running for Dear Life

And the University of Michigan did a study that concluded Michigan traffic accidents have a higher external cost to society than crime.
See DetNews: Traffic crashes cost Michigan $9.1B, more than crime

These reports gave me the impetus to mention something that I neglected in The Mandate Of Complete Streets.

That is Culture. What makes walking part of a culture and why are some areas safer? Is there a culture of safety?

When I think of a walking culture I think of the U.K. Specifically, The Ramblers. Walking is so important to the fabric of English society that the Ramblers ensure that at least once per year every foot path in the U.K. is traveled in order to maintain the public's right-of-way.

Can we have that? How do we make walking safely part of our culture when for the last 50 years the United States has been expanding roadways and making roads safer for vehicles but dangerous by design (Transportation for America PDF report) for everything else? How does the culture buy into the idea that more than vehicles move?

While Complete Streets are a new thing in the U.S., the similar concept of Living Streets has been in England since 1929.

So we could wait 80 years and let the ideas of Complete Streets filter through the culture, or we could use data to drive our decisions.

At my job I analyze data sourced from across Michigan and establish baselines of how many Internet problems per number of devices is normal and then look for areas with abnormal trouble rates and search for ways to lower that baseline rate.

When I read the University of Michigan Transportation Research Institute study: Societal costs of traffic crashes and crime in Michigan: 2011 update, I realized similar data was available in the study's data source: 2009 Transportation Data Center
Data Set Codebook

We had accidents per county and the census can give us population. Perhaps I could apply them?

I found some Michigan web sites with traffic crash data:
-Michigan Traffic Crash Facts
-Michigan State Police Traffic Crash Statistics
-Michigan State Police Traffic Crash Reporting Information

They had the reports I was looking for as PDF's:

-2010 Michigan Traffic Crash Facts for County/Communities
-MICHIGAN STATE POLICE CRIMINAL JUSTICE INFORMATION CENTER CRASH STATISTICS NUMBER OF CRASHES REPORT STATEWIDE TOTALS FOR 01/01/2010 THROUGH 12/31/2010 (all caps is the original format)

Methods

I used the 2010 Census to get population numbers.

I exported the crash data from the PDF's to a spreadsheet.

I then calculated median accident rates per number of people in the community and also plotted these on a graph to look for trends.

I did not expect to see any trends or correlations as there seemed to be so many different variables that can have an effect on traffic accidents. But that is not what I found.

Results

The calculated median accident rate for Michigan in 2010 is 32.2 accidents per 1000 people. And it all fit on a trend line (which surprised me):



Next I uploaded the tables to OpenHeatMap to see if there was any pattern to which counties were above this 32.2 accident rate and which were safer. Green is a lower accident rate and red is a higher accident rate by population.

Link to larger version: Michigan County Accident Rate (You can hover over each county to see its Accident Rate score)


It appears to me that rural counties have a higher rate of accidents when weighted for population.

I then applied the same methods to Bicycle Accidents and Pedestrian Accidents.

The calculated median bicycle accident rate for Michigan in 2010 is 0.13 accidents per 1000 people.



Full size Map: 2010 Michigan Bicycle Accident Rate



The calculated median pedestrian accident rate for Michigan in 2010 is 0.15 accidents per 1000 people.



Full size Map: 2010 Michigan Pedestrian Accident Rate


The Bicycle and Pedestrian Accident rates do not show as strong a correlation as total accidents but there is still a pattern.

When looking at the county maps it appears to me that the counties with a strong biking culture have the highest rate of bicycle accidents. These would be counties hosting large Universities where many students use bikes out of necessity and Grand Traverse County where people choose to ride.

It is harder to make sense of the Pedestrian Accidents map. It could be suburban walkers who don't have access to sidewalks are in greater danger.

To explore this possibility I made a map of the Walk Scores Of Michigan's 65 Most Populous Cities with data from WalkScore:



What you see is that city cores have higher walk scores and the suburbs get progressively worse (clearly evident in Wayne County). But is this related to safety?

At MichiganTrafficCrashFacts.org there is a Data Query Tool that lets you build specific maps and tables for defined areas. I used it to look at Traverse City and Grand Traverse County.

2010 Crashes in Grand Traverse County involving pedestrians:

You can see that though many pedestrian accidents were reported within Traverse City proper these usually did not result in injury. But the pedestrian accidents in Grawn, Kingsley, and Williamsburg while fewer in number resulted in serious injury and fatalities.

2010 Crashes in Grand Traverse County involving bicycles:

What I see on this map is more bike accidents downtown, but worse injuries outside of downtown.

What do we do?

Based on these maps and tables I believe that implementing design concepts such as Complete Streets can make roads safer for people, whether they are walking, riding a bike, or driving a car. And I believe that if we make the roads safer for all forms of transportation then more people start using those other forms of transportation. The economy, freed from the burden of unnecessary accidents, grows.

By bending the accident trend lines we can change the arc of our culture.

There are still many questions though and I hope that the research here can serve as a baseline for the future. Two big questions I look forward to having answered are:

-do communities that implement Complete Street designs see their Accident Rate decline?
-do communities with better WalkScores have lower accident rates?

For anyone who wants to do their own research I have uploaded my spreadsheet to Google Docs from there is it easily exportable.

The Mandate Of Complete Streets

(Today's post at MWaT: Are Our Driving Skills A Collective Effort? reminded me to finish this post that I started earlier this summer)

When I think of Complete Streets I think of streets that are safe for everyone. And by making streets safer we lower what economists term externalities or "social costs".

A street designed as complete will be safer for everyone resulting in a net economic gain to society.

In other words, what is a life worth? Not just to that person's family and friends but to the economy as a whole? What are the economic benefits if lawsuits are kept out of the courts, insurance isn't used, employees don't miss work, first responders are available for other emergencies, and on and on?

Traverse City has had numerous conflicts this year between street users.

Example from 9and10: Two Bike, Car Crashes In One Week, Police Cautioning Everyone Be Safe

These pedestrian-bike-vehicle conflicts are happening across the country just as they did in 2008 when there was a spike in gasoline prices forcing people out of their cars.

The most well known accident this summer is the case of Raquel Nelson whose 4 yr old son was struck and killed while attempting to cross a multi-lane road (See NPR: Child's Death Casts Light On Pedestrian Traffic Woes)

A similar tragedy occurred in Traverse City in 2007. See the Record-Eagle:Boy from Greece, 6, killed in accident on U.S. 31

The boy's family stopped in the turn lane halfway across the road to wait for traffic to clear...

As a parent it is hard to imagine anything more horrific than having my child being run over by a semi-trailer while I helplessly watch and knowing design choices played a part in the tragedy.

Doesn't seem appropriate to call these accidents as if they were unpreventable.

Plenty of studies indicate the dangers poor street design poses. See Wired: Report: Streets Pose Mortal Threat to Pedestrians

More than 47,000 people were killed walking the streets of the United States between 2000 and 2009

And while dedicated bike lanes can improve safety for bicyclists pedestrians are always the most susceptible street users as a recent bike-pedestrian accident in San Francisco demonstrates (via NPR).

In the case of Raquel Nelson she was facing three years in jail for jaywalking, the person who was in the car that killed her son? Two years of jail time.

And here we have the problem. It seems that in a state where we are free to walk the beaches of the Great Lakes we are not welcome to walk across the street.

What Grist calls the criminalization of walking.

This is a design decision. Driving requires concentration though we act like it does not. It is why I won't even talk to my passengers when I drive. Yet I still feel the same urges to speed or to use my vehicle to "teach a lesson". We all drive on the road given to us. Apply the neuroscience of behavioral economics to roads and design streets for people.

That is my three word description of Complete Streets: design for people.

This is my hope for Complete Streets in Michigan. A stronger economy by design. And not just in the reduction of negative externalities, but as Fast Company reports complete streets build jobs: Want Jobs? Build Bike Lanes

Cycling projects create a total of 11.4 local jobs for each $1 million spent. Pedestrian-only projects create a little less employment, with an average of 10 jobs for the same amount of money. Multi-use trails create 9.6 jobs per $1 million--but road-only projects generate just 7.8 jobs per $1 million.

Complete Streets Are For Everyone

NPR had a story this week on how Complete Streets make streets safer for pedestrians who are crossing them. Especially for those people who cannot sprint across an intersection.

As America Ages, A Push To Make Streets Safer

Including Seniors and the less mobile.

This is a concept that doesn't get much coverage - social costs.

When pedestrians are unnecessarily injured there is a cost to society that is accrued - lost wages, lost productivity - plus the opportunity cost of having medical personnel respond to an accident that could have been prevented by better design.

Rather some people shout the simpler slogan of "unfunded mandate". Yes, unfunded mandates are a burden but in this case it ignores the fact that it is a concept to guide a design process for when roads are built or repaired so the money is already there. I like to save the unfunded mandate accusation for when it really is a problem.

Do people in earthquake zones call building codes an unfunded mandate? No. Because like the Complete Streets design concept, taking time to do things right the first time saves people from having to pay a lot at some later time.