Tempe Traffic Collisions

There have been 4 bicyclists killed in Tempe traffic collisions on city streets (excludes limited-access highways) over the past 5 years [five year period 2010-2014); at the same time dozens of motorists and 14 pedestrians have been killed.

[UPDATE: There were zero bicyclist fatalities in 2009, and 2015; there was one in 2016. So since the 2016 data came out we can say: there have been a total of 5 bicyclist traffic fatalities in the past 8 years]

Scope of the Problem

For the figures in this report, a 5-year time period, 2010-2014 was selected (the most recent available at the time; 2015 has since become available). Many additional crashes occur (14,000!) occur in Tempe on limited access highways; these crashes are not included.

There were 21,167 traffic crashes reported in the period, below are the number of people, by person type, involved:

ePersonType count
DRIVER 41476 *
PEDESTRIAN 436 *
PEDALCYCLIST 1107 *
PASSENGER 14168 *

* not counting limited-access highways: I have the data, I just didn’t bother to pull it. contact me if you’re interested

Below are the number of people, by person type, killed:

Persons count
MOTORIST 21 *
PEDESTRIAN 13 *
PEDALCYCLIST 4

* not counting limited-access highways: there were an additional 32 motorists, and 1 pedestrian killed on freeways in Tempe city limits.

The five fatal bicyclist crashes (this covers years 2009 – 2016):

2010-05-10 Right angle at signalized intersection. Cyclist disregarded signal.

2010-05-17  Right angle at signalized intersection. Motorist disregarded signal, ultimately motorist pleaded responsible for too fast for conditions.

2013-10-03 Right angle at signalized intersection. Wrong-way sidewalk cyclist collided with right-turning motorist.

2014-06-12 Right angle at signalized intersection. Wrong-way sidewalk cyclist collided with turning motorist. [this was coded as Guadlupe, apparently in error, so it’s included here, click thru the date for full details][update: FARS and ASDM disagree: ASDM says the motorist was turning right; FARS says left; and also says the bicyclist violated the signal. FARS, the federal data, is normally much more accurate. I don’t have the original crash report]

2016-02-02 Right angle at signalized intersection (freeway off-ramp). Bicyclist is said to have ignored signal.

In any event, consistent with other urban areas, strike-from-behind tends to be rare. In five years there have been zero such fatalities (and longer term data continues to show zero, current dataset on-hand runs 2009 thru 2016, eight years).

Amount of Bicycling

Although bicycle use data is sparse, Tempe has more than most US cities, here are a couple of data sources

  • Bike counts at selected locations have been conducted for the past several years by the Tempe Bicycle Action Group []. The bike count data is particularly interesting because it also measures the amount of wrong-way, and sidewalk bicycling.
  • The amount of commuting by bicycle is often used as a proxy for relative amounts of bicycling.  The ACS (American Community Survey; conducted by the US Census Bureau) shows that 4.2% (margin of error 0.6%) of workers commuted by bike for the period 2008-2012[]. An LAB report[] based on just 2012 ACS says the rate is 4.5%.

2015 Update

Without re-hashing the 5-year figures above; a couple of observations. One is there were no bicyclist fatalities in Tempe in either 2009 or 2015 — leaving the 7-year toll at 4.

There continues to be a noticable drop in the overall number of bicyclist incidents which began on the state-level in 2012 (more here). In the city of Tempe, the year over year drop in 2015 to 132 represents a drop of almost 33%. It’s not known why there was such a sharp drop (less being reported?), but it is well below the 2009-2014 trend, here are those figures (get query here):

204 / 198 / 223 / 245 / 238 / 210 / 132

Does Targeted Enforcement Work?

OK, that’s a teaser headline because I have no idea. It does seem like it would be wise to link enforcement to traffic collision history. Unfortunately this does not seem to ever be the case.  E.g. it was reported on 7/26 there there’s some sort of concerted effort by Tempe PD going on all week at the intersection of College and Alameda, a 4-way stop. I have noted elsewhere, with videos, that almost 100% of drivers (and presumably bicyclists) do not make a full stop when there is no conflicting traffic. This is a violation.

This is the intersection of two low-speed streets; with relatively low (vehicle) volume (and very high bicycle volume, as College is a major bicycling artery); and since 4-way stops tend to be inherently very safe… it would be expected to be very safe, and lo and behold… What does the data show? Reported in EIGHT YEARS:

  • There were ZERO bike-MV collisions
  • There were five MV collisions; four were no injury, one possible injury
  • There was one ped-MV where the ped suffered a non-incap injury. The driver was at fault for running the stop sign, and hit-and-ran (this is a felony).

Crash Map

Below is a  static snap-shot of the location of each fatal collision in the city (excludes freeways), for each fatality where a location was reported (i need to double check; I’m guessing all fatals reported a location). I’m looking for better icons.

Click  here for a fusion table/map of all Tempe crashes. There you can filter by victim-type (ped, bicyclist, motorist, etc), and any other of many fields. To get only City of Tempe PD, to exclude freeway crashes, simply filter on Oncic and un-tick the DPS box…

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References

Tempe Bicycle Action Group 2014 Count Data.

Modes Less Traveled—Bicycling and Walking to Work in the United States: 2008–2012 [.pdf][supplemental tables]. Also, 3.7% (margin of error 0.7%) walked to work, see supplemental Table 5.

WHERE WE RIDE Analysis of bicycling in American cities. the LAB. [.pdf]

Queries

The first set of three are Tempe PD only (excludes DPS / highways), Count people by persontype, and total number of crashes; the second set  counts by city — i.e. includes both Tempe PD, and DPS investigated (and a small number of other agencies, e.g. sheriff’s office).

SELECT count(*)
FROM ( 2012_incident AS i )
LEFT OUTER JOIN LOVNcic ON i.OfficerNcic = LOVNcic.ID
WHERE LOVNcic.name ='Tempe' AND i.IncidentYear IN ( 2010, 2011, 2012, 2013, 2014, 2015, 2016) ;

SELECT p.ePersonType, count(*) FROM ( 2012_incident AS i JOIN 2012_person AS p ON i.IncidentID = p.IncidentID) LEFT OUTER JOIN LOVNcic ON i.OfficerNcic = LOVNcic.ID WHERE LOVNcic.name ='Tempe'  AND i.IncidentYear IN (2010, 2011, 2012, 2013, 2014, 2015, 2016) GROUP BY 1;

SELECT SUM(TotalMotoristsFatalities), SUM(TotalNonMotoristsFatalities),
SUM(TotalMotoristsInjuries), SUM(TotalNonMotoristsInjuries)
FROM ( 2012_incident AS i )
LEFT OUTER JOIN LOVNcic ON i.OfficerNcic = LOVNcic.ID
WHERE LOVNcic.name ='Tempe' AND i.IncidentYear IN (2010, 2011, 2012, 2013, 2014, 2015, 2016) ;

SELECT count(*)
FROM ( 2012_incident AS i )
LEFT OUTER JOIN LOVCity ON i.CityId = LOVCity.id
WHERE LOVCity.name ='Tempe' AND i.IncidentYear IN (2010, 2011, 2012, 2013, 2014, 2015, 2016) ;

SELECT p.ePersonType, count(*)
FROM ( 2012_incident AS i JOIN 2012_person AS p ON i.IncidentID = p.IncidentID)
LEFT OUTER JOIN LOVCity ON i.CityId = LOVCity.id
WHERE LOVCity.name ='Tempe' AND i.IncidentYear IN (2010, 2011, 2012, 2013, 2014, 2015, 2016)  GROUP BY 1;

SELECT SUM(TotalMotoristsFatalities), SUM(TotalNonMotoristsFatalities),
SUM(TotalMotoristsInjuries), SUM(TotalNonMotoristsInjuries)
FROM ( 2012_incident AS i )
LEFT OUTER JOIN LOVCity ON i.CityId = LOVCity.Id
WHERE LOVCity.name ='Tempe' AND i.IncidentYear IN (2010, 2011, 2012, 2013, 2014, 2015, 2016) ;

select * from incident where (OnRoad LIKE "Alameda%" and CrossingFeature LIKE "College%") OR (OnRoad LIKE "College%" and CrossingFeature LIKE "Alameda%");

todo, make this into a fusion table (or do OffNcic=tempe?):
SELECT
i.IncidentID, i.IncidentDateTime, i.IncidentYear,
sF_Bicycle, sF_Pedestrian, sF_Motorist, sF_OtherUnk, sF_Motorcycle,
i.OfficerId, i.OfficerNcic, i.ExtendedNcic,
OffNcic.name Oncic,ExtNcic.name Encic,
i.eCollisionManner,
i.eLightCondition,
i.TotalUnits,
i.TotalMotorists, i.TotalNonMotorists,
i.TotalInjuries, i.TotalFatalities, i.TotalMotoristsInjuries, i.TotalNonMotoristsInjuries, 
i.TotalMotoristsFatalities, TotalNonMotoristsFatalities,
i.eInjurySeverity,
i.InjurySeverity,
i.HitAndRunFlag,
LOVCity.name City, 
i.OnRoad, i.CrossingFeature,
i.Latitude, i.Longitude,
i.eTrafficWayType,
i.eIntersectionType,
i.eJunctionRelation,
i.eWeather
FROM ( 2012_incident AS i )
LEFT OUTER JOIN LOVNcic AS OffNcic ON i.OfficerNcic = OffNcic.id
LEFT OUTER JOIN LOVNcic AS ExtNcic ON i.ExtendedNcic = ExtNcic.id
LEFT OUTER JOIN LOVCity ON i.CityId = LOVCity.id
WHERE LOVCity.name ='Tempe' AND i.IncidentYear IN ( 2010, 2011, 2012, 2013, 2014, 2015, 2016) AND Latitude>0 ;

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