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How To Build Roads To Control How Fast You Drive
An anonymous reader writes "They're the holy grail of transportation engineering: streets and highways specifically designed to encourage automobilists to drive less quickly, reducing the rates of passenger fatalities and generally encouraging a safer urban environment. And now new research shows that, if built right, they just might work. A new study out of the University of Connecticut suggests that minor reductions in vehicle speed are possible through changes in the street environment. Through the use of roadside parking, tighter building setbacks, and more commercial land uses, road designers can make drivers subconsciously drive more slowly." All of that is gonna work a lot better than my strategy of placing car-sized holes covered with twigs and branches randomly every half mile or so down the interstates.
Good grief. From TFA:
And:
Who would have thought that by reducing a driver's visibility, the driver would go slower to give themselves time to react to surprises? You? You in the back? Are you some kind of smartass? The Connecticut Department of Transportation studied this for four years. There's no way you could have arrived at the same conclusion so quickly!
This study was useful in determining how much people slowed down -- quantifying it at about 10% -- but sweeping on to claims like, "reducing the rates of passenger fatalities and generally encouraging a safer urban environment" is silly. Streets packed with parked cars, pedestrians, nearby buildings, et. al. are generally more dangerous precisely because clear lines-of-sight are cut off. Sane drivers know this, reduce their speed, and then -- making wild hand-waving guesses, here -- wind up with about the same overall level of "dangerousness" as when driving on uncluttered roadways.
All of that is gonna work a lot better than my strategy of placing car sized holes covered with twigs and branches randomly every half mile or so down the interstates.
Nonsense, be a little bit more persistent. Apply for a government grant. Work out a deal with the overpopulated prison system to allow test inmates good behavior parole if they survive the course. Conduct a double blind study to see which method drivers prefer.
... in the name of science! I mean, the dystopian Mad Max future isn't going to herald itself!
Don't underestimate your ideas, you may have something here. I think with a few minor modifications (like filling the pits with black mambas or loaded claymores) we could gently urge drivers through natural human fears to drive slower. I'm already afraid of getting a ticket when I speed, why not step it up a notch or two?
Conduct your experiments
My work here is dung.
1) You can make the road look more dangerous, e.g. with optical illusions to make it look narrower
2) You can make the road actually and obviously more dangerous, e.g. reducing sight lines and adding on-street parking
Number 2 works, but it doesn't increase safety. Number 1 works... for a while. My concern with #1 is that drivers will realize they are being fooled, and start speeding up again. That's OK, except they may then interpret the real situation that the illusion was imitating as an illusion, and fail to take it into account, resulting in a net decrease in safety.
All of that is gonna work a lot better than my strategy of placing car sized holes covered with twigs and branches randomly every half mile or so down the interstates. Sadly, your strategy seems to have been widely adopted across the UK recently. I preferred the speed cameras - at least they didn't destroy your suspension ..
Studies show that drivers adjust to the speed at which they feel safe, regardless of posted speed. So the only way to make them go slower is to make the road inherently *less* safe.
Also, similar studies show that driving about 5-10 mph faster than posted is actually about the safest speed you can go.
http://www.motorists.org/speedlimits/
There's also the argument that restricting the ability to drive quickly kills, as you slow emergency response vehicles as well. http://www.bromleytransport.org.uk/Ambulance_delays.htm
All in all, one of the dumbest proposals I've ever heard. It seems that one of the easiest mistakes to make as an organization is to try to optimize for one contributing factor (speed) while ignoring the point of restricting that factor in the first place (reducing accidents).
Most roads are already quite curvy in Europe and I'm pretty sure new roads are constructed in the same manner to encourage lower driving speeds. Straight lines make people want to speed, lots of turns and twists make people want to break, so maybe making all your roads as straight as possible and thus creating grid-like layouts isn't such a good idea after all.
A side effect of less straight roads could also be a decline in traffic jams, because curved lines are longer than straight ones and thus can hold more cars.
Pretty good is actually pretty bad.
speed bumps also greatly slow down emergency vehicles. If you have ever been in an ambulance going over speed bumps you will curse the name of whoever came up with such a painful idea
the preceding post was not spell checked... suck it.
In Portugal I saw a cute system - if you pass a sensor driving faster than the speed limit, then a traffic signal 200yards/metres down the road turns red for 10 seconds, making you (and again anyone behind you) stop.
The psychology behind these systems is interesting - both rely on shaming you in front of other drivers. The Portugese system goes further and makes other drivers angry with you for speeding.
As a former employee of an international road transportation company, we studied the exact same thing.
Interesting fact. When someone is driving in a place they don't know, they drive slower. You can duplicate the effect by making changes to a known environment, like this study does by adding cars to the roadside. Second interesting fact? Once the changes become 'known', speeds return to what they were previously. I notice this part is somehow absent in the claims that "the lower speeds make things safer."
If I was from the University of Connecticut, I'd be embarrassed to be releasing this study.
It is my experience that congested roadways are considerably more dangerous than ones with free flowing traffic, and when you slow down traffic you also increase congestion. It may be the case that free flowing traffic has more deadly accidents (due to the higher speeds involved) than accidents on congested roads, but the congested roads have a much much higher rate of accidents.
But as a person who actually drives, it always bugs me when I see these studies that invariably conclude that the worse you make driving, the safer it is. First it was cities with no street signs, and pointless traffic circles, and zigzags in the road, or just traffic lights programmed to jam up traffic as much as possible. Now we're going to remove the safety margins between vehicles and magically improve safety.
Maybe I'm nuts, but it seems like city planners would prefer it if just nobody drove at all and just took mass transit everywhere, which would be wonderful if they actually had usable mass transit outside of the city center.
I read the internet for the articles.
Sane drivers know this, reduce their speed, and then -- making wild hand-waving guesses, here -- wind up with about the same overall level of "dangerousness" as when driving on uncluttered roadways.
I remember reading about a study done for motorcyclists, they were observed riding both with and without a helmet. Those that normally didn't wear a helmet were asked to wear one, and in response to the 'added safety' increased their speed to compensate.
People take a set amount of perceived risk, what they need to do is find ways to make a situation seem more dangerous than it is, as people would overcompensate and thus safer.
Looking at this from an evolutionary POV, it makes sense that a population would evolve to have a certain amount of risk-taking on the part of its individuals. Often when a risk is taken, and the result is poor, the individual takes the punishment (often death), but when the result is positive the population benefits, thus populations with a certain amount of riskiness flourish (enough to advance, not enough to be wiped out). Consider the new food problem, most populations have a set of known good food, known bad food and unknown food; they eat the good food and mostly avoid the bad and unknown foods. Some individuals will eat the unknown foods, if it is bad they die, and the population is largely unaffected, if it is good, the new food is then eaten by the population and everyone benefits.
But outside of interstates and restricted-access roadways, roads are used by more than just automobile drivers.
Buses are stopping and going, pedestrians are walking to work or going shopping, people are parking, deliveries are being made, and cyclists and motorcyclists are going about their daily business.
There is a benefit for making streets usable for everyone -- it increases the livability of a community, reduces urban sprawl (and the associated financial and environmental costs), and allows the elderly and disable to live more independent lives.
Now before someone starts ranting about how they pay tax on gas and thus roads should only be for cars, the gax tax does not come anywhere close to funding roads in the US -- a large portion of the money needed to maintain and build roadways comes from property taxes and the general fund.
So the conclusion is this: People can be induced to reduce their driving speeds when cars are parked along the roadways, when buildings are close to the street, and when those buildings include commercial rather than residential activity.
Wow. These people are idiots. Their plan is to make the roads less safe, so that it forces to make people drive slower, because driving slower makes the roads safer???
Not only that, but they are designing roads that in a few years* will be driven by self driving automobiles. These cars will always drive the optimal speed and so they are just slowing down the cars of the future.
*Perpetually ten.
Look where all this talking got us, baby.
First of all, "holy grail of transportation engineering"?? Bullshit. The goal of transportation engineering should be to achieve the best balance of maximized capacity, efficiency, and safety. You can always make roads safer by slowing things down - until you try to make them safer by causing congestion.. and the congestion causes frustrated and aggressive driving. The study basically says to throw more shit in the way of drivers to slow things down.. That's because it's creating an unsafe environment.. and drivers naturally try to compensate for it.
Here in Florida, the transportation engineers have decided that old people react slower. Therefore, all traffic lights change slower.. So that causes inattentive driving since people can be waiting as much as 5 minutes between lights. Then, people are very slow to start proceeding through the intersection once lights turn green - partly because desperate drivers run all the yellow lights because they have to wait another 5 minutes between lights. My argument would be that traffic rules should not change to accomodate for people unable to follow the rules. Chicago's lights change quickly at an intersection..
Also, our political wanker of a governor (Charlie Christ) decided he did not like the 'move over law' because he said it promoted speeding. So, people are free to sit in the left lane of major highways going under the speed limit while others try to get around them. Florida interstates are a clusterfuck.. Nobody moves over.. So you have a clump of cars bumper to bumper for a mile.. and then a mile of highway that hardly has anyone on it.. I would argue it would be safer to have an actual passing lane and allow people to spread out.
Cars today have more horsepower, more traction, better safety, and more braking power than cars 20-30 years ago.. Yet, our speed limits have decreased.. Why?
Traffic is an absolute mess.. and the idea that 'slower is safer' is contributing to that mess.
--- We need more Ron Paul!
That's what punishment really is for. It doesn't make sense to make the road less safe for everyone, merely to slow down the few people going well over speed limits. For those, you can fine, suspend their license, or even jail.
I would be surprised if assholes were deterred by narrower lanes. Anyone on a residential road who feels that *they* are safe at 90 mph isn't paying attention to rational queues.
How about designing roads that are safer to drive fast on.
Fast is good if it's safe
Around here, we have a law that says the state (as in US state) sets the speed limits on all roads unless a waiver is given to a locality (city or county) to override the speed limit that would ordinarily apply to a given road.
I'm sure the purpose is both uniformity (so everyone "knows" how fast to drive on unfamiliar or unposted roads) and to prevent municipalities from changing speed limits arbitrarily (speed traps, etc).
The side effect to this in the larger urban areas is that in response to heavy traffic, people seek out residential through streets as means around the major arterial streets, which are clogged. The people living on those streets hate the traffic and the speeding that goes with it, so the residents are able to petition the council to get speedbumps installed on their streets.
IMHO these suck. One, they don't really slow or divert that much traffic. Usually you see people driving the speed limit and then braking hard at the speed bumps and then accelerating hard to get back to their speed limits. While I sympathize with the people living on those streets, they ARE through streets that belong to everyone who pays taxes, not private roads for the benefit of the residents -- you only ever see speedbumps in upscale residential areas.
I also think they are illegal usurpation of the state speed limits -- you can't drive the legal speed limit on the street without damage to your vehicle and/or creating a dangerous situation flying off the bumps.
Folks in our town have been trying to slow down traffic on one of the main routes that passes along a mixed-use corridor: residential housing, commercial, and industrial properties all along a half-mile stretch. The speed limit is 45 mph.
That wouldn't be too bad if not for two factors: 1) the street lies between a residential neighborhood and the local elementary school, and 2) there's a convenience store along the route with very high vehicle and foot traffic. Since we moved onto that stretch, we've witnessed about six accidents each year in front of the convenience store. The convenience store happens to be at the most-common crossing point for kids going to the school, too. Since we are living along the stretch and have young children, we've added our voice to local efforts to reduce the speed to 30 mph. The city would like the speed reduced, but it is technically a county road, and the county won't change it. For the past few years, we've told our kids not to play in the front yard (facing the street) or in the driveway. This year, we reversed ourselves. Just last weekend, we erected a basketball hoop in our driveway. As soon as we were out there playing, traffic started to slow down. Sometimes, unfortunately, to speeds well below 30 mph!
We figure it's only a matter of time before there is either an accident or before we get a letter from the city and/or county asking us to take down the basketball hoop. Some of the other residents along the route appreciate the change, but only time will show whether or not they start using their front yards and driveways again. For now, I'll enjoy the sound of engine breaking as the big trucks (the ones that want to run through the stretch at 55 mph!) slow down each time they see the kids in the driveway or the yard.
I use irony whenever I can, but my shirts are still wrinkled...
Here, I’ll save you both the trouble.
MPH vs. MPG in top gear (scroll down to the non-hybrid examples)
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
from J.G. Ballard's short story "Subliminal Man" ... "All around him cars bulleted along, streaming toward the suburbs. Relaxed by the smooth motion of the car, Franklin edged outward into the next speed lane. As he accelerated from 40 to 50 mph a strident, ear-jarring noise drummed out from his tires, shaking the chassis of the car. Ostensibly as an aid to lane discipline, the surface of the road was covered with a mesh of smaller rubber studs, spaced progressively farther apart in each of the lanes so that the tire hum resonated exactly on 40, 50, 60 and 70 mph. Driving at an intermediate speed for more than a few seconds became physiologically painful, and soon resulted in damage to the car and tires."
Road Fatalities per Vehicle-Kilometers (or miles) is indeed how this statistic is normal measured. However, the results still favor the UK over the US (but stay the hell off the road in the United Arab Emirates).
Country Road Fatalities per Billion Vehicle-Kilometers
Sweden 5.9
UK 6.3
Australia 7.9
France 8.5
USA 9.0
Canada 9.2
NZ 10.1
Japan 10.3
South Korea 19.3
UAE 310
Source: List_of_countries_by_traffic-related_death_rate
Support Right To Repair Legislation.
Require car manufactures to have speedometers that are accurate (and easily calibrateable) and I will support your proposal. Simply getting new tires can chuck the speedometer by 5MPH, nevermind other factors.
upon the advice of my lawyer, i have no sig at this time
The trick is not to make slower drivers, the trick is to make SAFER drivers. Slower drivers are not always safer drivers.
1) Set accurate speed limits so people will actually follow them. It is ridiculous that "following traffic" means having to break the law.
2) Mandate *better* and *harder* driver license tests. In the US it is all too easy for someone to get a driving license with little or no training. (seriously; check out this test: "Drive in a straight line, drive backwards in a straight line, parallel park, do a 3 point U-turn", and the kicker is, many states only require you to do TWO of the above. And if you fail the test, you can pay the fee and take it again, and in the mean time despite failing, you're allowed to continue driving with your permit.
3) Have the police start enforcing SAFE driving concerns. Enforce laws about people driving in the wrong lane, driving while on the cell phone, driving with improper equipment. Yes, I know, speeding tickets are great revenue, but stop enforcing only the speeding laws, especially when you're not making anyone any safer you're just picking up revenue from some unlucky sob (or more likely these days lining the pockets of a traffic lawyer).
If the focus was on safety, we could raise speed limits and increase traffic flow and reduce congestion.
disclaimer: I catch a lot of crap for driving a "sporty" car, but I focus all my attention on safe driving. driving should be a cooperative adventure, not a competitive sport. Take all the a-holes and distracted drivers off the road and we could all enjoy our commute and weekend drives a lot more. =) Just telling people to slow down, or trying to find ways to force them to slow down won't really change anything, other than perhaps an increase in speeding tickets. =/
If you're not passing, you shouldn't be in the left lane, period. I don't care if you're doing 50 or 80 MPH, the left lane is for passing! It's people like you that fuck up good traffic flow.
But the fact is, you are making the roads more dangerous! How can this be a good thing?
Because drivers are more careful, and rarely careless, when conditions are dangerous. People being careless is usually what kills.
Alaska sees dangerous, icy roads 2/3 of the year, yet our over-all accident and death rate is lower than the national average. Shouldn't it be the case that the nice, grippy streets of the lower 48 would be much safer?
We also tend to drive individually and do less carpooling and the like because destinations are so far apart. So again, dangerous roads seem on the surface to mean people drive more carefully, for a net reduction in accidents and loss of life.
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
This damn topic comes up all the time... Faster driving equals {more deaths, higher fuel consumption, etc}. And it's crap. Let's see... Even if given our current conditions deaths were reduced by slower average speeds the proposition of the article would not necessarily save lives.
Fine, build tighter setbacks... That means bringing the buildings closer to the road. This would lead to people living, playing and existing closer to the road. This means people stepping off their front porch and WHAM! Basically, were is the study that shows that bringing the buildings closer doesn't increase deaths more than is decreased by the reduction of velocity?
Do you REALLY want to decrease traffic fatalities? Fine.. Kill drunk drivers. No you don't get a second chance. Next, require driver road tests for licensing... EVERY year. Not just a "sign here on the dotted line"... but a god-damn TEST! Do it in a simulator. Simulate stalling an engine. Simulate a blown tire. Simulate a skid on ice. Simulate a 5 yr old jumping in front of you. Measure reaction times. Basically do for drivers what airline pilots have to go through. You don't have to handle everything 100% but you do need to achieve some sort of success to pass. No this is not insane. Pilots have to do it and the probability of them harming someone is far less than the operator of a motor vehicle. Thus we should actually require more of a motor vehicle operator. This would either weed out EVERYONE who is a poor driver or force them to educate and train themselves well enough to be acceptable drivers.
I will never live for sake of another man, nor ask another man to live for mine.