statistics

One Arizona legislator REALLY doesn’t like photo red cameras

Our legislative elves have been hard at work trying to de-rail photo-enforcement. Again (click here for last year’s festivities). The biggest single item is supposedly dead as of March 6, 2012 — this would have referred a ballot measure which would prevent cities and towns from using photo-enforcement.

Safety studies have consistently shown a net safety benefit for photo-red enforcement. Net means that there are fewer serious injuries and fatalities. A few studies have shown an increase in the number of collisions accompanying the safety gains. See, e.g. the IIHS study, Red Light Running Kills, linked at trafficsafetycoalition.com. Or more locally, also see Scottsdale-based redmeansstop.org.

Here is a list of items in the current session (50th 2nd Regular. The Spring of 2012) of the Arizona Legislature, assembled by the Traffic Safety Coalition:

SB1315 – mandate personal service or certified mail for photo enforcement tickets
SB1316 – mandate that photo enforcement cameras cannot take pictures of red light running violations unless the light has been red for at least one second
SB1317 – mandate a study of intersections with red light cameras
SB1318 – force photo enforcement companies to obtain a PI License for each worker
SCR 1029 – put photo enforcement ban to the voters for approval

As noted above Senate Concurrent Resolution 1029 is for the time-being anyway dead… The first thing I noticed that was odd is that they are all in the senate. Upon closer inspection all four of the the senate bills have only one sponsor, and all four are the same guy; a Frank Antenori (R-30, Tucson). He clearly doesn’t like photo-enforcement, and is apparently making it his life’s work to defeat it’s effectiveness; if not ban it outright.

Aside from safety issues, the cameras can, and do, provide evidence that has been used to solve crimes; including (that I know of) catching a hit-and-run driver who seriously injured a cyclist in Tucson, a hit-and-run-driver who killed a cyclist in Tempe, and a assault-robbery-murderer in Tempe.

Stats?

Arizona has a particular problem with red-light running; despite improvement over the years, Arizona continues to be over-represented. For example in 2009 Arizona had 37 red light running (RLR) fatalities while New York had only 29…. Arizona being three times as dangerous as New York on a per capita basis.

The words below, written over 10 years ago continue to ring true today, from a 07/13/00 article in USA Today, Ariz. has deadliest red-light runners in USA:

Arizona has the nation’s deadliest red-light runners, with three of the country’s worst cities for fatal intersection crashes, according to a study of federal transportation data obtained by USA TODAY…. Arizona had by far the worst death rate among states, with 6.5 fatalities for every 100,000 people… Arizona also had three of the four most dangerous cities. for red-light fatalities. Phoenix topped all urban areas, followed by Memphis, Mesa and Tucson

In addition, cities with speed limits of 45 mph and higher on surface streets faced more serious red-light -running accidents… The Phoenix police officer says said that with an average of 330 days of sunshine a year, it’s typically usually perfect driving weather. That doesn’t mean motorists drive perfectly, however. Just the opposite. “If we got more rain or inclement weather, maybe it would slow people down some, particularly at the intersections,” Halstead said says. “As it is, they zip around the city at a pretty good clip.” And, according to the institute’s study, Phoenix drivers run red lights at an unrivaled pace. The city has by far the nation’s deadliest rate of fatal red- light running crashes, nearly five times the national average. Arizona and other fast-growing Western states have been particularly stung by red light crashes “because their wide open roads are suddenly seeing schools, businesses, and busy intersections crop up,” says said Phoenix traffic engineer Paul Wellstone. “The West has a reputation for being a drivers’ paradise; a place you can lay on the accelerator and not worry about the traffic and dangers. That’s changing now. Cities are struggling with getting their citizens to slow down.”

The FHWA has a page on red light running.

Is Phoenix Safe?

[ Updated Sept 2018; this year’s Allsate 2018 America’s Best Drivers Report lists Phx rather low (less “safe” than average); not sure if anything has changed in methodology(?). ]

Sept 2015 Update: Each year we’re treated to this recurring tidbit of stupidity via Allstate Insurance press release which always gets picked up and published in the media: Arizona’s urban drivers score well for safety. ‘Well’ for safety? Unfortunately Arizona remains significantly less-safe (i.e. more dead bodies) than average in US, and far worse than the best state. Like as much as hundreds of percent worse, depending on which metric is chosen (VMT vs. per capita)
NHTSA state-by-state stats.

Phoenix was reputed to be America’s 7th safest city, according to this survey which looked at three factors relating to insurance. Clearly the stuff of newspaper-filler stories. Intrigued, I see that the survey involves ranking cities in three categories 1) Crime, 2) Natural disasters, and 3) Traffic safety; though it wasn’t clear how they were weighted. For example, traffic fatalities claim far more lives than murder, and the number of deaths in the U.S. due to natural disaster is miniscule.
That being as it may, their source for traffic safety rankings is the “Allstate America’s Best Drivers Report” (tm!), which Allstate claims “Reveals Safest Driving Cities”.

What it actually measures is the statistical likihood of having an auto insurance claim. Which Allstate claims, and I think sounds reasonable, as a proxy for the number of MV collisions. The next leap, which is demonstrably false, is that fewer collisions translates into “safety”. One glaring data point is enough to disprove this: cities of similar size are frequently and for good reasons ranked against one another; it just so happens that Phoenix and Philadelphia have virtually the same population, and are currently the 5th and 6th largest city in the U.S. Actual fatality data reveal that Phoenix is significantly more dangerous than Philadelphia, yet Allstate’s proxy data says just the opposite:

NHTSA Fatality Data				Allstate data
City	Killed	population	killed per 100K		time between collisions	rank (higher=worse)
Philadelphia	95	1547297	6.14	60.2% worse	6.2 years	187
Seattle, WA	30	616,627	4.87	25% worse	8.0 years	147
Phoenix AZ	159	1593659	9.98	1.1% better	10.1 years	74

Source: NHTSA Traffic Safety Facts 2009 (latest year available), Table 124 811402.pdf, and Allstate (follow link above; current year result they refer to as 2011, is similar to 2005-2010 ). Notes: overall U.S. fatals/population/ratePer100K = 33,808/307,007,000/11.01

So, Allstate’s data merely shows that Phoenicians suffer from fewer fender-benders than Philadelphians; but say nothing about safety.

Why is Phoenix so dangerous? The main reason is probably because it’s “Dangerous by design”, with a higher priority on moving more cars, at higher speeds; and a lower priority on getting everyone to their destinations without being killed. More driving could explain some but not all of the gap; this, in itself, a symptom of poor land-use choices.

I threw Seattle into the table simply because of this recent op-ed that aggravated me: why-seattle-is-safer-than-phoenix. Phoenix and Seattle are quite dissimilar in population, but here again the Allstate data claims Seattle is significantly more dangerous than Phoenix when just the opposite that’s true.

2014 Update

Here’s the figures based on Allstate released in Sept 2014. Phoenix is the “best” large city at 9.2 years; and coincidentally Philadelphia is the “worst” large city at 6.2 years.

Auto Insurance Center Fatality Statistics

An outfit called the Auto Insurance Center put out a statistical roundup that looked only at fatal crashes (covering data years 2005-2015) and then normalized each stat to each state by population, and then ranked the states. It’s a FARS data-mining exercise that comes up with sometimes curious stats of dubious value but interesting nonetheless, e.g. “Fatal car crashes caused by road rage were the most prevalent in Indiana (almost 13 fatalities per 100,000 residents)”. Variations like that tend to come from wide variations in reporting, not that there’s a lot more road rage in one state versus another.

By the way

I always have trouble finding this page at www-nrd.nhtsa.dot.gov (which can be found by searching for FARS, then clicking on “publications”) where it lists publications like Traffic Safety Facts; e.g. 2009 Traffic Safety Facts Data Summary Booklet ; and 2009 Traffic Safety Facts FARS/GES Annual Report, they list back to about earlier 1990’s.

FARS and PBcat

Commencing with the recently-released 2010 data FARS (The USDOT’s Fatality Analysis and Reporting System) will have far more specialized detail on Pedestrian and Bicyclists crashes.

“Motorist Failure to Yield — signed intersection” One of several dozen crash types defined by PBCAT

618 cyclists (person type 6 bicyclist, and 7 other pedalcyclist) were killed in 2010 in traffic collisions — and as noted at the link above, only collisions with motor vehicles in-transport are tracked by FARS. So for example, a bicyclist who lost control and died as a result of crashing into a tree would not be tracked here, nor would a bicyclist who strikes a parked motor vehicle. Continue reading “FARS and PBcat”

Is Bicycling Safe? Is Bicycling Dangerous?

Short answer: As with all modes of transportation, it entails some danger.

Longer answer: yes, similar to the risk of motoring — perhaps twice as risky. but how to measure? (per mile, per trip?). Bike-MV collisions are currently running 2% of all in AZ. Bicycling represents perhaps 1%, i.e. twice the risk.

For the moment, this is going to be a catch-all for links and related info on the topic. Links:

crash-injury-rates-by-mode-of-travel and crash-injury-rates-by-mode-of-travel-2/ these contain stats on per-trip, and per-mile fatality risk by mode; bike/ped/passenger car/motorcycle
2019 The Risk of Dying Doing What We Love published a neat chart that compares a broad range of activities; it uses commercial airline travel as the benchmark and attempts to list an exposure (by time) adjusted risk value; i.e. driving is 4X as dangerous, bicycling is 8X as dangerous (i.e. cycling is twice as dangerous as driving in a car). Motorcycling comes out as 100X, i.e. 25 times worse than driving. (also noted in my article here)
collection from Ohio Bicycle Federation: “Cycling is Safe” subhead.
www.bicyclinginfo.org/facts/crash-facts.cfm
kenkifer.com/bikepages/health/risks.htm now via archive.org
http://www.bicyclinglife.com/EffectiveAdvocacy/BicycleMyths.htm
Mighk Wilson’s essays freedom from fear, and I am not a Bicyclist.
Another essay in the same vein by a UK sociologist Dave Horton: Fear of Cycling.
My posts about the books How Risky is it Really? and Free Range Kids.
Alan Solot: Tucson bike vs. car crashes aren’t increasing March 2016 op-ed style piece breaking down some Tucson-specific figures
UK gov’t study showing how the usual measures of cycling safety tend to overstate the danger… “This research dispels the idea that risk for UK cyclists is substantially higher than for drivers or pedestrians” “we found that for young male cyclists between 17 and 20 years of age, cycling was markedly safer than travelling by car” “Surveys from many countries show that time spent travelling has remained fairly constant over time at about one hour per day, despite large changes in modal split . This supports the use of risk based on time as being most appropriate for comparing modes with different average speeds”. It covers risk expose measures that tend to favor driving, like comparing per mile, rather than, say, per trip. I think this is all obvious stuff but it’s good to have it quantified, if only for the UK; the same mechanisms seem to be applicable to US. full text: Exposure-Based, ‘Like-for-Like’ Assessment of Road Safety by Travel Mode Using Routine Health Data Jennifer S. Mindell, Deborah Leslie, Malcolm Wardlaw. Here’s a road.cc story about it.
Rick Vosper has an excellent 3 part series in BRAIN, part one Haunted by the Ghosts of Dead Cyclists addresses the media bias, and danger exaggeration “There is nothing the media likes better than a dead cyclist. Unless it’s a dead cyclist who was not wearing a helmet. That salacious and often completely irrelevant bit is invariably tossed in…”
Pedestrian danger/risk: “Of the 711 pedestrians who have died in traffic collisions since 2014, only four have been killed by bicycles” — We’ve Blamed Traffic Deaths on Bicyclists Since 1880. What About Drivers?

Continue reading “Is Bicycling Safe? Is Bicycling Dangerous?”

Final 2010 U.S. Motor Vehicle Traffic Fatalities released

Final 2010 figures

…released 12/8/2011; fastlane.dot.gov, at 32,885 the number is slightly higher than the early estimates which come out in the spring.

The 2010 dataset is not yet available in FARS, which is a little strange given that last year’s data was released in September (i.e. 2009 dataset available September 2010). update: the 2010 FARS data came up sometime in early December.

Final Arizona 2010 figures were released in August.

NHTSA’s Traffic Safety Facts 2010 Motor Vehicle Crashes: Overview, DOT HS 811 552

Bicyclist Fatalities

As bikinginla.wordpress.com points out, 618 cyclist deaths in 2010 makes it the lowest overall figure in some 35 years. The Arizona figure, 19, puts it close to our 10-year average; coming off of a bad 2009 (25).

Ped Problems?

USA Today article: “The USA is getting riskier for people on foot, and experts aren’t sure why.” Mike Sanders noted the ped issue, see comment here on the final Arizona 2010 figures. Speed matters and need to redefine mobility – “Everyone should be familiar with the chart that shows that a pedestrian hit by a car traveling at 20 miles per hour (mph) has an 85 percent survivability rate. That same collision with a car going twice as fast, 40 mph, will lower the survivability likelihood to 15 percent” (Laplante and McCann, Complete Streets: We Can Get There from Here, ITE journal, May 2008).

An rather than viewing it as a zero-sum game where motorists must lose mobility in order to make streets safer for peds; Beyond Safety in Numbers suggests that the safer streets for peds are quite likely safer streets for motorists as well.

Early Estimate of Motor Vehicle Traffic Fatalities in 2010

The early estimates come out in the spring (late march i think), here was the buzz at that time…

The media is abuzz with projections released a couple of days ago by NHTSA that 2010 traffic fatalities are at there lowest number since the Truman administration, and the closely-watch per VMT figure is the lowest ever recorded. Early Estimate of Motor Vehicle Traffic Fatalities in 2010:

A statistical projection of traffic fatalities in 2010 shows that an estimated 32,788 people died in motor vehicle traffic crashes. This represents a decline of about 3 percent as compared to the 33,808 fatalities that occurred in 2009… The fatality rate for 2010 are projected to decline to the lowest on record, to 1.09 fatalities per 100 million VMT, down from 1.13 fatalities per 100 million VMT in 2009

Here are the Early Estimates for 2009, and 2008. Continue reading “Final 2010 U.S. Motor Vehicle Traffic Fatalities released”

Arizona has the highest cycling fatality rate?

[updated October 2010: Final data for 2009 has AZ as 4th highest bicycling fatality rate (per capita, i.e. per population). See e.g. this media story referring to the BSAP]

Tied to April being bike month in Arizona is of course a crop of media stories.

Imagine how surprised I was to read that “Arizona has the highest cycling fatality rate, based on population in the United States”. Continue reading “Arizona has the highest cycling fatality rate?”

ADOT’s Bicycle Safety Action Plan Study

ADOT’s Bicycle Safety Action Plan Study ( the study’s home-page link is now dead ) is a multi-phase plan to assess and improve bicycle traffic safety, with emphasis on Arizona state highways. In urban areas that often means the interchanges. Here are direct download links to final reports:

BSAP Final Report; Appendix A (September 2012)
and the somewhat related PSAP Final Report (June 2009. An update to PSAP is in MPD FY 2016 Work Program)

During the five-year study period “There were a total of 9,867 bicycle crashes statewide in Arizona… crashes that occurred on state highways were extracted from the statewide data set. There were 1,089 bicycle-motor vehicle crashes reported on state highways between January 1, 2004 and December 31, 2008” from this a focus area was determined, within the focus area there were 746 bicycle crashes. PBCat was used to crash-type all 746 of these collisions.

Thus this data set accounts for a small minority of bike-MV crashes, around 11%. But Working Paper 1, table 15 offers a useful comparison between the studied data and all statewide data. For example, we see the same suspiciously-high percentage (24 to 25%) of “other” fault ascribed to bicyclists as with other studies. As I’ve written before, the “other” fault is generally the result of a poor/improper crash investigations that tends to wrongly faults cyclists who are doing nothing illegal (see Understanding Collision Summaries) — this is statistical proof of poor-quality investigations are a statewide problem for bicyclists. This is a shortcoming of the crash reports, and not the BSAP; in Working Paper 1, figure 20, something they call “primary contributing factor” by crash group is assigned overwhelmingly to motorists (67%), and only 24% to bicyclists.

Press coverage

There was a lengthy, front page A1, Arizona Republic article by Sean Holstege on Sept 17, 2011 which perhaps was intended to be about the plan but did wander, understandably, to general topics. For example they make great hay out of the per capital fatality stats, without any discussion of how to interpret them — e.g. how weather probably affects them, with Arizona being more of a year-round cycling state; or a higher per capita usage, e.g. Arizona has significantly higher (than US) percentage of commuters (according to census figures, see Working Paper 1, Table 1 — Arizona is 0.9% versus 0.5% nationwide).

The story, as many “bicycle safety” stories do, lacks context of traffic in general. So, for example, there was a chart of the number of bike-MV collisions (about 2,000/year total). There is no mention of the fact that that represents only a tiny fraction of all MV collisions ( which ran well over 100,000/year over the study period). And though it mentions the number of fatalites, say 25 in 2008 — it never mentioned the total number of traffic fatalities (it runs around, and lately something under, 1,000 per year).

So here are some hard numbers, over the five year period 2004 – 2008 there were 681,466 MV crashes, of which 9,730 were bike-MV — a little less than 1.5% (taken from the historical overview in the 2009 Bicyclist Fatality study, which were gleaned from AZ Crash Facts — note that the numbers a slightly different in the BSAP, but I don’t know why). The number of fatalities is 4,943 total, 132 bicyclist; or 2.67% — so bicyclist fatalities were somewhat over-represented but not dramatically so.

Note that the ADOT plan by design is aimed at the small percentage of bike-MV crashes that occur on the state highway system. “The majority of bicycle crashes in Arizona (approximately 90 percent) occur on local, city, and county roadways outside of ADOT jurisdiction”

Also, by the way, the article inaccurately stated that the BSAP recommends a mandatory taillight law. That was in an earlier draft but was since removed — I don’t believe there is adequate evidence to support the additional burden on cyclists. The article does correctly mention that the BSAP recommends state-level sidewalk law clarifications, which seem like a worthy endeavor, given the huge proportion of sidewalk-related collisions, along with the current legal murky morass that currently exists when cyclists who cycle on the sidewalk subsequently collide with vehicles in crosswalks and driveways.

The raw data from the 746 crashes studied can be viewed and mapped at this google fusion table. I also read the data into a mysql database, bsap, password access available upon request using a scheme analogous to asdm and presently only available on mysql.azbikelaw.org, and not on the godaddy server.

The crashes studied were full-blown pbcat 2.0 with crash types, groups, cyclist’s direction; that’s the good news. The bad news is it’s not clear how that relates to bicyclist crashes in general.

Fatal vs. non-fatal: The dataset mentioned above, the 746 crashes includes only 4 fatalities and is data only from the focus area. The BSAP report has several charts and graphs that refer to 24 fatalities. The distinction is that the total 24 is over the entire SHS (state highway system); whereas the 4 is only the focus area. I don’t have the raw pbcat data for the 24 (or rather , the other 20).

BSAP-esqe Data

Here is a bunch of data extracted via query from ASDM data — currently covering years 2009-2014. In other words, it is an attempt to automate the types of data presented in the BSAP but applied to all Arizona bike-MV crashes, not just state highway system.

Summary of PBCAT results

Many of the motorist drive out’s (from stop signs, or performing a right-turn on red) involve counter-flow sidewalk cyclists. Out of the 746 crashes studied here are the top 5:

Table 5 – Top 5 Crash Types 
Percentage of SHS Focus Area Crashes Crash Type Description 
103 13.8% Bicyclist Ride Through ‐ Signalized Intersection
 83 11.1% Motorist Drive Out ‐ Sign‐Controlled Intersection
 76 10.1% Motorist Drive Out ‐ Right‐Turn‐on‐Red
 71 9.51% Motorist Drive Out ‐ Commercial Driveway / Alley
 61 8.17% Motorist Drive Out ‐ Signalized Intersection
746       Total SHS Motor Vehicle‐Bicycle Crashes

—

Also interesting title of this PBIC presentation How to Create a Bicycle Safety Action Plan: Planning for Safety. It’s from the toole design people so, as expected, is filled with nacto and facilities stuff.

ADOT 2010 Crash Facts

ADOT’s 2010 Motor Vehicle Crash Facts has just been released.

Highlights are the total number of fatalities continued to fall; there were a total of 762 persons killed in 2010, a 5% decrease from the year before.

There were 19 bicyclists killed on Arizona’s road in collisions with motor vehicles in 2010, which compares favorably with the 25 killed in 2009. That means there are two (possibly three) missing from this tally for 2010.

The MOST COMMON DRIVER VIOLATION is (remains) Speed too fast for condition

There were 106,177 crashes in total, of which 1,914 were bike-MV crashes.

Dangerous by Design

[updated regularly; the one release in May 2014 can be found at smartgrowthamerica.org I don’t think anything much has changed Phoenix and Arizona still rank “high” (bad) ][direct download of 2016 edition]

While we’re on the subject, t4america.org released the latest version of their recurring report Dangerous By Design 2011; where metro-Phoenix has a recurring, starring role as a particularly dangerous place for pedestrians — the 8th worst rate in the US. The only places significantly higher are basically several (!) metro areas in Florida.

Bad for pedestrians tends to translate into bad for motorists and bicyclists, as well — in other words, we’re all in this together. Arizona’s motorist fatality “VMT rate is over twice as deadly as Massachusett’s. The disparity in per capita rate, since Arizonans drive more miles, is even worse…. more”

But you are not likely to hear anything about how or if or why Arizona isn’t closing the gap; or even that a gap exists! — rather that deaths overall have merely fallen. Here is a typical new-release-style story: azfamily.com story

Back to the DbyD report, they have this concept called PDI, the Pedestrian Danger Index; Phoenix-metro at 132 is many times worse than, for example, Boston-metro at 21.6.

And just to throw out a factoid, for the year 2009 (the most recent year for which detailed stats are available) there were more bicyclists killed within the City of Phoenix (9) than were killed in the entire state of Massachusetts(6).

The population of Phoenix is 1.5M versus State of Massachusetts having 6.5M…. The C.O.P., accused rightly as being an enormous-sprawling place covers 516 square miles, the state of Massachusetts 7,840 square miles of land area.

John Allen’s blog reflecting upon the fact that in the DbyD report, the Boston-metro area came in dead last (SAFEST!) of all large metro areas in US — “Strange, isn’t it — the Boston area has repeatedly been derogated as supposedly having the nation’s craziest drivers”.

Arizona’s Rural Highway Traffic Safety Problem

A couple of days after the data was released, and somewhat to my chagrin, the arizonarepublic/news/articles/2011/09/02/20110902arizona-deadly-rural-roads.html did a fairly long and detailed piece on what ADOT is doing to identify and address rural highway problems… though, interestingly, the latest Crash Facts shows a steeper decline in rural as opposed to urban fatalities.

So far, no one that I know of, has said or suggested that Arizona’s high rate of rural fatalities is what accounts for Arizona’s overall high traffic fatality rate. Perhaps that is so?

As mentioned in the article, rural fatal crashes tend to be single-vehicle — though that is a little misleading because a bike-MV, or ped-MV crash is defined as a single-vehicle.

Here are the number of fatal crashes split by urban/rural for 2009 and 2010:

Peds fatal crashes, total/urban/rural: 156 / 102 / 54 ( 2009: 121 / 77 / 44)

cyclists killed, total/urban/rural: 19 / 17/ 2 ( 2009: 25 / 17 / 8 )

(all inclusive) Number of fatal crashes, total / urban / rural: 698 / 354 / 344 (2009: 709 / 299/ 410)

…

Here is some discussion of the 2010 National results: early-estimate-of-motor-vehicle-traffic-fatalities%C2%A0in%C2%A02010/

IIHS Driver Fatality Rate Stats

The IIHS does this every so often, e.g. see here for their report from a couple of years ago.

So, the latest is Dying in a Crash, Vol 46, No. 5, June 2011. It covers 2005-08 model year passenger vehicles during calendar years 2006-09. It also specifically only covers driver fatality rates.

The big news is that SUVs, which long have had higher death rates than passenger cars — due to the much higher rollover deaths — have become safer, due presumably to the prevalance of ESC (electronic stability control) in newer model SUVs.

There is no accounting for attempt to account for danger imposed on others.

What the WSJ Thinks

The WSJ has been running the same editorial and op-eds for as long as there’s been a CAFE (Corporate Average Fuel Econonmy, probably 30 years old now) Continue reading “IIHS Driver Fatality Rate Stats”

Manner and Fault in Bicyclist Traffic Fatalities: Arizona 2009

Abstract

Traffic records for all bicyclist fatalities occurring in Arizona during the year 2009 were categorized and listed according to manner of collision and assignment of fault. Primary results are that 11 of 25 fatalities (44%) were determined to be the fault of the cyclist; while 14 of 25 (56%) were the fault of a motor vehicle driver. The most common manner of collision is when a driver strikes a cyclist from behind.

Full Report

The full report is available in pdf format:
Manner and Fault in Bicyclist Traffic Fatalities: Arizona 2009
Supporting data: 2009CyclistFatals.xls

Comments or questions may be left here, or contact me.

There were some somewhat out-of-context statements about my report on the npr.org health blog. They probably should have mentioned that the report covers only FATAL bike-MV collisions (a tiny fraction of all bike-MV collisions), and that the manner of collision in fatals varies significantly from non-fatals.

Continue reading “Manner and Fault in Bicyclist Traffic Fatalities: Arizona 2009”

Arizona bicyclist fatalities 2003-2006

How did I miss this one?

Should State DOTs Prefer Bicycle Lanes or Wide Curb Lanes? A.L. Dennison, 2008 [.pdf] This report was produced for ADOT in cooperation with US DOT/Federal Highway Authority.

Bicycle facility advocates have long debated the respective merits of bicycle lanes (BLs) and wide curb lanes (WCLs); this report investigates their claims… This study found no apparent relationship between fatal bicycle/motor vehicle collisions and type of bike facility… A significant handicap to any analysis of bicycle travel or safety is the paucity of reliable data.

Of great interest to me was the categorization of bicyclist fatalities over a four year (2003-2006) period, based on police reports. Somehow I missed this report entirely even as I echoed its complains about the “paucity of reliable data” for cyclist/traffic collisions while researching Manner and Fault in Bicyclist Traffic Fatalities: Arizona 2009.

According to my (from ADOT’s Arizona Crash Facts) records there were 15, 27, 35, 30 fatals in 2003, 2004, 2005, and 2006, respectively. This totals 107, but the report says that “We obtained 85 (97%) of 88 microfilmed fatal bicyclist/motorist crash reports submitted to AzDOT by police agencies in Arizona between 2003-2006”. The missing 3 (88-85) are explained in a footnote. But one wonders, where are the other 19? (=107 – 88). Does that mean that not all fatalities are submitted to ADOT? … so the answer i am told is that it covers the time period 17-Oct-2003 to 25-Sept-2006, which makes sense.

U.S. lagging in reducing traffic fatalities

AP Story U.S. lagging in reducing traffic fatalities. With all the feel-good news items about how fatality rates are supposedly so low, it’s good to get some perspective. The US is way behind in reigning in traffic deaths, and has fallen behind most other developed countries in both per-mile and is waaay behind in per-capita rates. Traffic deaths remain the leading cause of death for a huge swath of Americans.

And Arizona is even worse than US averages. For contrast, see what we’ve done with photo-enforcement in Arizona.

The large improvements in particular in US in the past few years are likely simply the result of poor economic conditions (no job means no job to drive to; and no money to spend driving around) — and not of some sort of systemic shift. Continue reading “U.S. lagging in reducing traffic fatalities”

Obtaining Police Reports

As part of my project to monitor the most serious bicycle – vehicle collisions, I will be obtaining the Arizona Crash Report(ACR) for every bicyclist fatality in 2009. Continue reading “Obtaining Police Reports”

Pre-preliminary 2009 Bicyclist Fatality Report

[update: this posting has been superseded — please see:

Manner and Fault in Bicyclist Traffic Fatalities: Arizona 2009

which has detailed, finalized stats and discussion]

First, some perspective: In the state of Arizona, approximately 1,000 people are killed per year in traffic collisions of all types. The number of cyclist (usually called a “pedalcyclist” in the jargon) fatalities fluctuated between15 and 36 per year over the past twenty years, with an average of about 25/year.

[as a sidebar, Arizona total traffic fatalities which have been as high as 1,293 just a couple of years ago, were down to 937 for 2008. The exact cause of this happy trend is a matter of great debate, e.g. the effect of economic recession, and photo-enforcement. Even after this dramatic reduction Arizona roads remain significantly more dangerous than US averages ]

I have become increasingly frustrated by what seems to me to be short-shrift paid to analysis of crashes resulting in a cyclist’s serious injury/fatality Continue reading “Pre-preliminary 2009 Bicyclist Fatality Report”

It’s official; 2009 state-level NHTSA traffic fatality figures published

Get them here.

Here’s a typical national news story, from the LaTimes Traffic Deaths and Injuries Plummet in 2009: “Fatalities drop 9.7% from 2008 as the number of deaths dips to its lowest point since 1950, the Transportation Department says.” The official toll for 2009 is 33,808.

Closer to home, the total for 2009 in Arizona of 807 traffic fatalities represents a significant year-over-year drop that began in 2006, when there were 1,293 fatalities.

Per mile (VMT) figures won’t be available for awhile; it appears Arizona, which is consistently more dangerous than US averages will continue to close the gap.

Per capita figures show Arizona, again, consistently more dangerous than US averages, but continuing to improve.

Bicyclist Statistics

Bicyclists, statistically did not fare well in 2009. At 25 deaths, that is 6 higher than 2008, bucking the overall trend. Though the usual caution applies, the number of cyclist deaths is (thankfully) quite small, so a variation of just a few makes large percentage differences, and trends are harder to discern year-over-year.

Prior to the official release, i was aware of 16 fatalities; I am now aware of another 9 but they are identified only by date time and (usually) location — but not name. I was shocked to find out that Phoenix had 9 fatalities, of which I only knew about 4 previously. How can that be?

You can view a summary spreadsheet of each of the 25 fatalities here.

There is a detailed report available: Manner and Fault in Bicyclist Traffic Fatalities: Arizona 2009.

Arizona “Benefits”?

The Arizona Republic’s take included the odd conclusion that “Arizona benefits from being a younger state” thus the roads here are newer thus safer.

Arizona benefits from being a younger state. Because most development here is relatively recent, the roads are newer and designed to safer, more modern standards.

That means wider lanes and shoulders, better signs, smoother curves and banks, more guard rails and more innovations such as rumble strips, which are ruts in the sides of highways that alert drivers when they veer off the road.

“These are things people drive by every day which they may or may not notice. But they all contribute to make our roads safer,” said Laura Douglas, an Arizona Department of Transportation spokeswoman.

Rumble strips, for example, reduce the accident rate by a third, she said. ADOT also paints extra-thick road stripes, installs new guard rails that cushion crashes and uses larger, easier-to-see traffic signals, Douglas said.

Arizona traffic death toll drops to a 16-year low 9/11/2010, The Arizona Republic

This might be true in isolated examples, such as the rumble strips. Overall, though, this ignores the human-behavior dimension of driving. So, e.g. newer roads are much wider and straighter and the likely result is that drivers will drive faster. Maybe you’ll get relatively fewer wrecks but the ones that occur will be more violent as a result. If you look at the state-level NHTSA figures you will find the safest state is….. drumroll please… Massachusetts! A very old state. Arizona’s VMT rate is over twice as deadly as Massachusett’s. The disparity in per capita rate, since Arizonans drive more miles, is even worse.

Massachusetts happens to be the safest state in the US, but it’s not an outlier, the relationship holds up generally — states where most development pre-dated automobiles have far lower death rates, and vice versa.

“Better” roads also have a vicious circle effect of raising the number of miles driven, thus exposing one to more risk, albeit a decreasing risk per mile. In other words, dwelling on rate per VMT is misleading. Likewise, “better” vehicles, which are from an engineering perspective are much safer, have not yielded the expected improvement. Since as usual, human-behavior kicks in and drivers, knowing their vehicles are “safer”, (unconsciously or not) drive just a little more risk.