Alternate Solutions to RLC

Here are some of the alternatives to installing red light cameras, and the studies that show that they work.


Alternative Number 1, Lengthen the yellow signal time:

A 2004 Texas Transportation Institute study found, "crashes decrease with an increase in yellow interval duration and a reduction in speed limit." After 1.0 second was added to the yellow signal timing at test intersections, accidents dropped by 35 to 40%. This compares with a 6.4% reduction for "area-wide officer enforcement of intersection traffic control devices... during the time of the enforcement activity".  Also, "an increase in yellow interval duration decreases severe crashes. For example, an increase in yellow duration of 1.0 s is associated with an MF of about 0.6, which corresponds to a 40 percent reduction in crashes. This reduction is consistent with the effect of yellow interval duration on red-light violation frequency".
http://tti.tamu.edu/documents/0-4196-2.pdf

An earlier 2003 study by the Texas Transportation Institute specifically on yellow signal timing concluded, "an increase of 0.5 to 1.5 s in yellow duration (such that it does not exceed 5.5 s) will decrease the frequency of red-light-running by at least 50 percent; drivers do adapt to the increase in yellow duration; however, this adaptation does not undo the benefit of an increase in yellow duration".
 
Here is a 2001 report by the US House of Representatives that shows lengthening the yellow time significantly reduces red light running(70+%):

In 2012, a study by Virginia Tech on calculating yellow signal times was published. This study concluded that ITE minimum yellow signal times proved to be inadequate in their tests, “Traditionally, the recommended yellow time for the 72.4 km/h speed limit(45mph) is 4.3 s... using the proposed 1-second PRT(Perception-Reaction Time) and 3 m/s2 deceleration level requires an 85th-percentile yellow time of approximately 4.53 s, which is longer than the 4.3-second recommended yellow time. The recommended yellow time corresponds to only a 12.6 percentile, which means that most of the drivers will encounter a yellow time that is shorter than what is needed; i.e., they will be trapped in a dilemma zone. In order for these drivers to be able to avoid being in a dilemma zone, they either need to react faster (have short PRTs) and/or brake harder (have higher deceleration levels)”.
http://bit.ly/10r8zCG
 
Also in 2012, the University of New Mexico released a study about increasing yellow signal times at 20 Albuquerque, New Mexico intersections which showed, “These findings generally support the literature which notes that at intersections where yellow light timings are increased and all-red clearance intervals are implemented red-light running crashes are reduced.”.
http://www.thenewspaper.com/rlc/docs/2012/nm-longeryellow.pdf
 
The state of Georgia passed legislation in 2008 forcing municipalities to add one additional second to intersections that have red light cameras installed at them(http://www.legis.state.ga.us/legis/2007_08/pdf/hb77.pdf) and now Georgian cities that had RLCs installed are seeing ticketing rates fall dramatically(72% on average) after complying with the new law. "The additional time on the yellow light has significantly reduced the number of citations because motorists have adequate time to get through the intersection," state Representative Barry Loudermilk (R-Cassville), primary sponsor of the new legislation, wrote in his weekly column. "Since most of these cities have stated that safety was the primary reason they installed red light cameras, they should be thrilled that citations have been significantly reduced; however, many are pulling the cameras out because they are no longer making a profit."
In November of 2009, the city of Loma Linda, California(which had RLCs installed for over 4 years at that point) lengthened their yellow light time at their 5 RLC intersections by one additional second and saw a 92% drop in red light violations. In December 2010 the city let their contract with RLC vendor Redflex expire without renewing it as a result.
 
In April 2011, the city of Arnold, Missouri raised their yellow signal times by 0.3 to 1.0 seconds and saw an immediate 70% decrease in red light running that has been sustained for several months.
http://www.fox2now.com/news/ktvi-longer-yellow-lights-in-mo-are-stopping-red-light-runners-20110622,0,699828.story

In August 2011, the city of Milton, Florida reported that they had seen a reduction in red light camera citations of 60% due to increased yellow signal time.  “By increasing the yellow light [time], we’ve had a positive effect on red light running to almost 60 percent..."
 
In April of 2013, this website compiled a report on thee effects of raising yellow signal times using, in part, information from the City of St. Petersburg as evidence of the benefits of lengthened yellow signal times.
 
Here is a website dedicated to the lengthening of yellow light times:
http://www.shortyellowlights.com/


Alternative Number 2, Add "SIGNAL AHEAD" pavement markings in front of the dilemma zone of intersections:

A study conducted in Orlando, FL and published in 2010 shows that simply adding MUTCD-approved "SIGNAL AHEAD" pavement markings in front of the dilemma zones of an intersection leads to more than a 25% decrease in red light running violations. There are other recent studies using driving simulators that also show that these markings significantly reduce red light running violations.


Alternative Number 3, Use Advanced Dilemma-Zone Detection Systems:

For several years the FHWA(Federal Highway Administration) has sponsored research Advanced Dilemma-Zone Detection Systems, which use cameras to monitor approaching vehicles and adjust the length of the yellow and green signals at an intersection to find the best length for each light cycle to optimize safety and intersection throughput. These systems have been tested for several years in Texas and are currently in a wider roll-out in 8 other states and they have shown to reduce red light violations by 82%. They also have the positive side effect of increasing intersection capacity.


Alternative Number 4, increase the all-red time and try more than one other alternative at once:

Here is a study from AAA Michigan and the city of Detroit relates more to alternatives to red-light cameras if safety is the primary concern: "Improvements such as enlarging traffic light lenses by 50 percent, re-striping left turn lanes with pavement markings, re-timing the traffic signals, and adding an all-red clearance interval (when you leave both sides red for a second or two while the signals are changing).During the first 27 months of the four demonstration projects, crashes decreased by 47 percent with a 50 percent reduction in injuries. "
http://www.motorists.org/photoenforce/home/aaa-michigan-study/


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St Pete Driver,
Dec 23, 2012, 5:23 AM
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St Pete Driver,
Apr 19, 2013, 3:54 AM
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St Pete Driver,
Apr 2, 2013, 10:18 AM
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St Pete Driver,
Apr 1, 2013, 3:40 PM
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