GELFAND’S WORLD-It has often been a source of curiosity to me how it is that our nation, for all its obsession with highway safety, manages to continue to kill people in large numbers. How do fatal accidents actually happen, stripped of all the cliches? Is it anything like what we are used to seeing on television?
Wednesday evening provided a chance to discuss the topic with an expert, Captain Rolando Solano, who commands the West Traffic Division for the LAPD. It turns out that there is some good news, but there are also some facts that merit concern.
In the westside areas that Solano commands, it is sobering to consider that although there are about 20-25 homicides over the course of a year, there are nearly twice that level of deaths due to traffic accidents. In fact, the LAPD has its own acronym "AK" for automotive incidents that result in a substantial injury (that's the "A") or a death (that's the "K"). The LAPD has officially taken note of the vehicular death total and is trying to reduce it. We might interpret this as the realization by the LAPD that we don't have to accept traffic fatalities as an inevitable fact of life, but rather as a really bad thing that we may be able to do something about.
In attempting to write a prescription for some ailment, it helps to obtain the best possible diagnosis. What are the mechanics or proximate causes of traffic fatalities?
Interestingly, the way that people get killed in traffic, at least in this one area, pretty well fits our preconceptions. Roughly half the fatalities are the result of a car hitting a pedestrian. As Captain Solano pointed out, it's simple physics. Another substantial contingent involves a car hitting a motorcycle. Again, it's the case of a large, massive object colliding with a much smaller bike, resulting in an even smaller person being thrown into the automobile.
There's one consolation for the rest of us. A relatively small percentage of traffic deaths occur to people who are safely buttoned up in their cars. Such things do happen from time to time, but you are a lot safer all wrapped up in a metallic cocoon than being on foot. The captain mentioned the introduction of side airbags as an improvement.
Some driver deaths do occur. The interpretation is that speed is the most important precipitating element. Cars driven fast and smashed into a building or a telephone pole can result in the death of a driver or a passenger.
Let's go back to the motorcycle mortality and morbidity for a moment. Left turns gone bad are a particularly serious part of the problem. A large SUV making an abrupt left turn into the path of an oncoming motorcycle is a recipe for a collision and, therefore, serious injury to the cyclist.
A few facts about speeding up traffic flow in real time
Think about gridlock. You've been sitting on Crenshaw, trying to go north towards Wilshire, and you're stuck. One reason is that at intersections, cross traffic continues to fill the intersection even after your light has turned green. Or maybe it's a long block you are on, and only some of the cars between you and the next green light make it across the intersection. In either case, you are in gridlock, and you are frustrated. It turns out your city has some surprises for you.
You are probably vaguely aware that Los Angeles has a lot of cameras looking at traffic. They are most obvious on the freeways, but they are also on the city's streets. We also have sensors mounted under the pavement in lots of places. You can recognize them by the circles that you can see, typically near an intersection. We have about 4500 of these sensors.
The camera pictures (in real time) and the sensor data go to something called the Automated Traffic Surveillance and Control System. It also has an acronym, ATSAC. [http://trafficinfo.lacity.org/about-atsac.php] It turns out that ATSAC is actually doing what you, the driver, were already hoping for. How do you get rid of gridlock on Crenshaw due to all that cross traffic? The operators at the ATSAC, looking at the traffic jam, can take countermeasures. One way, seemingly paradoxical, is to slow the traffic on Crenshaw by increasing the length of time covered by one or more red lights. This will give the cross traffic a chance to clear, resulting in fewer cars from those cross streets gridlocking the system.
Another way to move traffic is, of course, to hold the cross traffic for a while, thereby allowing you and your fellow Crenshaw drivers to move along. Of course the ATSAC operators have to do this sort of thing for lots of streets going in all directions, and out of these multiple interventions, traffic flow is improved.
So even with all our frustration over the slow crosstown traffic, we can at least enjoy the realization that something intelligent is being done about it. Otherwise, it would actually be worse.
The Magnitude of the Problem
The number of cars moving through our road system is actually pretty astonishing. Here's one statistic that begins to explain our frustration. If you take the five busiest intersections on the westside and measure the total traffic flow, you will find that 81 million cars pass through them (combined) over the course of a year. Since most of this traffic is concentrated over a 12 hour period of each day, you can figure out that this averages to about 60 cars passing through each intersection every minute. This goes on, minute after minute, hour after hour, day after day. Of course some hours are worse than others, so the traffic loads during the rush hours can be fearsome.
There is only so much land area that can be covered with streets and freeways, so the situation doesn't have any immediate solution. We have a lot of cars, a lot of drivers, and only so many miles of road. The city of Los Angeles is actually doing what it can to synchronize signals so as to move traffic with the most efficiency, but the people who run the ATSAC explain that they cannot solve traffic gridlock all by themselves.
Here's one more number that should be of interest. In those 5 intersections with their 81 million vehicular crossings, there were a total of 127 traffic accidents. In other words, it takes almost a million automobile crossings to generate one accident. That seems like a pretty good number, but it also represents a substantial number of damaged cars, injured people, blocked intersections, and tow truck calls. How do you get the accident incidence below one in a million? It doesn't sound like something that is very likely, but if we want to avoid those traffic blockages and injured people, we somehow have to do the impossible.
There are three main lessons here. The most important lesson is that we need to decrease collisions between cars and pedestrians if we want to attack the single most substantial element in traffic fatalities. How that can be accomplished is another question. It's not obvious that more police writing more tickets or going after more drunk drivers is the way. We just don't know for sure. Another lesson has to do with reducing collisions between cars and motorcycles. Again, it's not obvious how to accomplish this. Finally, it sounds like all those safety improvements that have gone into automotive design over the past 50 years are paying off. Safety belts, airbags, and reinforced doors are protecting people. What used to be fatal accidents have become fender benders. Of course if you decide to drive 120 miles per hour down a city street at 3 AM and you run into a lamp post, all those expensive safety items are probably not going to save you. But for the average Jill or Joe, doing 30 along Wilshire at 3 PM, you are a lot safer now than you would have been 70 years ago.
Note: These traffic and safety issues were explored at a large Town Hall meeting held at Venice High School on March 26, 2014. Our thanks to the convener, Jay Handal, and the numerous city officials and police officers who spoke to us.
(Bob Gelfand writes on culture and politics for City Watch. He can be reached at [email protected])
-cw
CityWatch
Vol 12 Issue 26
Pub: Mar 28, 2014