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However, I changed my mind once a I listened to a local police chief explain that in his city traffic accidents had actually risen at the intersections where the cameras were in use.

This is not unusual. The Federal Highway Administration found that red-light cameras increase rear-end collisions but reduce more severe right-angle collisions, saving $50,000 in collisions per intersection per year in medical and repair costs.

As a Traffic Engineer I work with this issue frequently. Their are numerous benefits of roundabouts that outweigh the risks, so much so that numerous states, including New York, require the analysis of a roundabout at any new intersection.

The first issue is safety, roundabouts reduce what we call, Conflict Points, between pedestrians, bicycles and vehicles. The middle island also provides pedestrian refuge for a two stage crossing. Roundabouts also force cars to slower speeds which improves safety and reduces the risk of an automobile collision.

As far as delay and driver in vehicle perception, roundabouts statistically have a lower average delay than all-way-stop-controlled (AWSC) intersections for streets that have a volume of less than 20,000 vehicles per day. The Level of Service (LOS), is a measure of driver perception of service at an intersection. The average LOS for an AWSC at peak hours is F (Delay of 172 s), while a roundabout provides LOS C (Delay of 21 s). Both LOS determinations are for the best approach. So as you can see, the benefits are clear.

The downside is that many people are unfamiliar with them, a learning curve and the unwillingness to try out something new, as the adage goes, "If it ain't broke, don't fix it". Here is an example, I met with a consulting firm that performed a study in Buffalo, NY to put in a roundabout. The measurements worked and LOS would have increased for the approaches. However after installation the city council decided to put stop-signs at the roundabout approaches, against the recomendation of the traffic engineers. This was a foolish move on the part of the City as a major benefit to roundabouts is the Yield approach. Their is still no change to date.

It is an uphill battle but once people become more familiar you will see them throughout the US.

If you would like more information on roundabouts their are two resources from the federal government:

1. Roundabouts: An Informational Guide

2. NCHRP (National Cooperative Highway Research Program) Report572

So which is better, a rear-end collision outside the intersection, or a broadside collision inside the intersection?

The Federal Highway Administration found that red-light cameras increase rear-end collisions but reduce more severe right-angle collisions, saving $50,000 in collisions per intersection per year in medical and repair costs.

So, the big question is, "did the redlight cameras reduce accidents or increase them?"

The Federal Highway Administration found that red-light cameras increase rear-end collisions but reduce more severe right-angle collisions, saving $50,000 in collisions per intersection per year in medical and repair costs.

So you support ticketing too slow drivers also? They're an equal risk.

http://www.tfhrc.gov/safety/speed/speed.htm

It is safety. The faster you go the higher the risk of fatality in an accident.

The U.S. Department of transportation's Federal Highway Administration review research on traffic speed in 1998.[19] The summary states:

* That the evidence shows that the risk of having a crash is increased both for vehicles traveling slower than the average speed, and for those traveling above the average speed.
* That the risk of being injured increases exponentially with speeds much faster than the median speed.
* That the severity of a crash depends on the vehicle speed change at impact.
* That there is limited evidence that suggests that lower speed limits result in lower speeds on a system wide basis.
* That most crashes related to speed involve speed too fast for the conditions.
* That more research is needed to determine the effectiveness of traffic calming.
http://www.tfhrc.gov/safety/speed/speed.htm

Seriously, red-light cameras have nothing to do with safety and everything to do with money making.

False. The Federal Highway Administration found that red-light cameras increase rear-end collisions but reduce more severe right-angle collisions, saving $50,000 in collisions per intersection per year in medical and repair costs.

Here are some more studies:
http://www.tfhrc.gov/pubrds/03jan/10.htm
http://www.ibiblio.org/rdu/sl-irrel/index.html

Speed limits, especially in the U.S., often are set too low

No, they aren't. The 10mph difference between e.g. 30mph and 20mph gives a massive increase in the chances of a pedestrian surviving in a collision.

Collisions between pedestrians and autos are overwhelmingly more often the pedestrian's fault. In fact, one study suggests that around half of pedestrian vehicle fatalities involve a ped under the influence of alcohol (scroll for it... lots of good info there, though.) More tidbits from there: The single largest contributor to vehicle-ped collisions is where the ped "ran into road" (At 15% of cases) while the most common contributor on the part of drivers is "failed to yield to ped". See especially Table 15; crashes which are solely the pedestrian's fault significantly outnumber those which are solely the driver's fault; shared-fault collisions are significant, but much lower than either.

The pedestrian's chance of survival, therefore, is very much up to them. If they stop running out in the road when they aren't supposed to and doing similar stupid shit, the majority of such fatalities will be eliminated. Further, you should never assume a car will stop for you even if you make eye contact with the driver. It's a lot easier to stop Chevrolegs than Chevrolet.

Right now I'm in Panama and people walk in the street a lot. Partly this is because ALL vehicle-ped collisions are legally the driver's fault, even on the Interamericano. But also, the majority of people here don't own a car. They need to be able to walk. We've given this up in the USA... You NEED a car to participate in modern American life.

Let me add -- if your theory were correct, the most common cause of accidents would tend to involve a car approaching from the rear. In only 3.9% is this the case.

This has been done before, and better, in California. See Demo 97.

There's considerable military interest in follow-the-leader systems for convoys. The military routinely drives trucks around in big groups. The US Army has a system in test where the lead vehicle (usually armored) leads a group of driverless trucks. That's to reduce casualties, not labor.

The fundamental problem with most automated driving schemes is that they address driving on freeways, which people don't mind all that much. Automatically retrieving your car from a parking garage or lot and bringing it to you would actually sell.

I'd much rather just have a car that could drive itself. That's not practical at the moment, either.

Sure it is. It's just terrifying to ride in, and the infrastructure isn't widely deployed. But if we could all just get over our silly fears about hurtling down the highway at 70 MPH just a few feet from the car in front of us, we'd have it already!

This sort of safety mechanism is stupid and expensive and really won't do much to save lives.

35% of pedestrian vehicle collisions are the fault of the driver only, according to this review. Even if we totally discount the lives of idiot pedestrians, approximately 2 700 pedestrians are killed annually through no fault of their own. One can make an argument that that is an insignificant number, and perhaps it is.

I too have seen my share of idiot pedestrians, but let me contribute my anecdote on the incompetence of drivers. As I was walking towards a major intersection, I witnessed a car careen off the road, through the street-sign at the corner I was approaching, along the sidewalk, and back onto the street along which I walked, where it finally came to a stop upon striking the opposite curb. I do not know how the driver managed to lose control so badly, and on such a straight road, but regardless, he managed it, and at the speed he traveled, would likely have killed anyone waiting at the intersection.

You're describing Demo 97. That had serious industrial and government backing, it worked, and it went nowhere.

It was essentially a trackway scheme. Cars followed markers (permanent magnets) in the pavement, could measure the distance to cooperating cars ahead and behind, and had some minimal radar-based obstacle detection. It required automatic-only dedicated lanes.

Anyway - when it comes to voting machines the requirements should be that they are mathematically verifiable for correctness. This essentially rules out Windows CE and a lot of other systems. Mostly since the complexity of those systems are too large.

Red light cameras increase the accident rate as often as they decrease it. Also, the real dangerous drivers that actually run the middle of the red light and T-bone innocent drivers, aren't paying attention. Before red light cameras they weren't paying attention in a situation where their life was at stake, now they aren't paying attention in a situation where their life plus a $100 ticket is at stake. It isn't a deterrent to the real problem.

Red-light Camera's save lives, and reduce the largest intersection related fatal accidents significantly. Red light running is a serious problem in this country, when the FHWA started their enforcement campaign with the states Red Light running was causing 1000+ people a year lose their lives to it and was/is the single largest cause of urban moderate speed automobile related fatalities. Not only that but rate of red light running was increasing dramatically year on year (upwards of 5% a year at heavy intersections). It was and still is a serious problem that cannot be dismissed.

A basic understanding of crashes is needed to realize why red light crashes are so deadly. The majority of red light running accidents involve right-angle crashes (commonly known as T-bone). Right-angle crashes are the single largest cause of intersection related fatalities because the side of the car is very thin and offers very little crash protection, (or as one manufacturer put it, crumple zone) add in the fact that SUV bumpers sit at the height of the head of the occupant of a car and you have a recipe for disaster involving serious and quite often fatal head injuries. Car manufacturers have actually started to respond to this increase in right-angle crashes by equipping automobiles with side-air bags, a very expensive ($2-3000) option solely to negate some of the effects of right-angle crashes which are almost entirely intersection related and almost always involve red-light running accidents.

The following FHWA study concluded that the red-light cameras result in a 1-40% (the majority declined close to 30%, there was a single jurisdiction where the decline was 1% and the jurisdiction involved was obviously choosing poor locations for camera equipped intersections) decline in right-angle crashes AND the number of accidents decline year over year as people become aware of the cameras. And when factoring in the increase in rear-end collisions the decline is still a very hefty 27% on average, but the corresponding rear-end collision increase results in almost no increase to fatalities. The conclusion of the study was clear, when used at intersection where there is a problem with red-light running the decline in accidents is not only significant it's quite large, and the year over year gains are nothing to ignore as they approach 50-60% decline, saving numerous lives every year.

http://www.tfhrc.gov/safety/pubs/05049/

The fundamental objective of this research was to determine the effectiveness of red-light-camera (RLC) systems in reducing crashes. The study involved an empirical Bayes (EB) before-after research using data from seven jurisdictions across the United States to estimate the crash and associated economic effects of RLC systems. The study included 132 treatment sites, and specially derived rear end and right-angle unit crash costs for various severity levels. Crash effects detected were consistent in direction with those found in many previous studies: decreased right-angle crashes and increased rear end ones. The economic analysis examined the extent to which the increase in rear end crashes negates the benefits for decreased right-angle crashes. There was indeed a modest aggregate crash cost benefit of RLC systems. A disaggregate analysis found that greatest economic benefits are associated with factors of the highest total entering average annual daily traffic (AADT), the largest ratios of right-angle to rear end crashes, and with the p

Cite? Anyhow, the rate of new infections (not the rate of carriers) in black women is 10x the general population. I'm going to guess that the rate among party-goers is somewhere in between. Even if it were the full 10x, you still only gain one order of magnitude, and you are still more likely to be fatally injured by a car while walking home from the bar.

Cite? Why wouldn't more pedestrians be struck during the night when they are less visible? Also, walking home from the bar, the pedestrian's judgment is likely impaired by alcohol. There. I took an argument out of my arse to match yours. ;)

>> Is the ticketting reducing the number of accidents?

if you are referring to the tailgate-detector tickets, nobody knows yet as there hasn't been enough time to find out.

if you are talking about speeding tickets and red light camera tickets. the answer is absolutely. many studies have shown that with higher enforcment of speed limits and red lights people DO change their driving habits, slow down, and obey signals. Further it has been proven that whith the slower speed of traffic not only are there fewer collisions*, but they are also less likely to involve injuries and death. I know the public perception is that it's a tax, but this is a really simple tax to avoid, don't break the law, and you will NEVER be caught doing so.

reference:
http://www.dft.gov.uk/stellent/groups/dft_rdsafety /documents/page/dft_rdsafety_029193.hcsp
http://ip.bmj.com/cgi/content/abstract/9/4/302
http://www.tfhrc.gov/safety/pubs/05048/index.htm
http://www.esafety-effects-database.org/applicatio n_15.html
and others... (google is your friend)

*I won't use the word accident in this context because the majority of the time it is no accident and any intelligent person can see exactly why it happened

Circle have one huge disadvantage compared to traffic lights: if one cross street is backed up, the circle backs up and then prevents the other cross street from moving.

Actually, we had that in 1997. See Demo 97, where all that was implemented in a live freeway lane in San Diego. Then funding was cut.

It also made sure there were large enough gaps between bridges and other structures to allow large aircraft to land within 10 miles of any point on the highway.

Good discussion of this at "The man who changed America" from the Federal Highway Administration publication PUBLIC ROADS. ...brig

Roundabout Safety Comes to America

Thats a common belief, but the US Interstate system was being planned during the 1930s, but other capital dam projects tied up men and concreate. Then the Second World War hit and the plan was shelved again.

The Autobahn as a tool of the Blitzkrieg sounds good, but in fact they were thought up in the 1920s in Germany and Switzerland and they were limited in scope even during the build up of the 1930s. The first section from Frankfurt am Main to Darmstadt opening in 1935. This straight section was used for high speed record attempts by the Grand Prix racing teams of Mercedes-Benz and Auto Union. During World War II, the central reservation of some autobahns was paved to allow their conversion into auxiliary airports. However, for the most part, the autobahns were not militarily significant, and most military and economic freight continued to be carried by rail. Thousands of kilometers of autobahns remained unfinished, their construction brought to a halt by 1942 due to the increasing demands of the war effort, as Germany always had manpower issues even with all the slave labor they used.

The interstate system was authorized by the Federal-Aid Highway Act of 1956 and championed by Eisenhower. In 1919 Ike had been involved in a National Defense planning operation to move units across the United States and it took months, similar operations by Patton before the war showed a need for better highway infrasturcture in the US. One potential civil defense use of the Interstate Highway System is for the emergency evacuation of cities in the event of a potential nuclear war.

http://www.tfhrc.gov/pubrds/mayjun00/onemileinfive .htm
"I have no idea where the one-out-of-five claim originated. Perhaps it is giving too much credit to whoever originated this "fact" to suggest that it began with a misreading of history. Under a provision of the Defense Highway Act of 1941, the Army Air Force and the Public Roads Administration (PRA), now the Federal Highway Administration, operated a flight strip program. In a 1943 presentation to the American Association of State Highway Officials, Commissioner of Public Roads Thomas H. MacDonald explained how it worked.

"A flight strip consists of one runway, laid down in the direction of the prevailing wind, and a shelter with telephone for the custodians at the site and for itinerant flyers in an emergency. Fuel storage facilities are not provided unless airplanes are based there permanently. Instead, oil companies will keep stocks of aviation gasoline at gas stations along the highway and truck it to the flight strip as it is needed."

The flight strips were designed for easy access to public highways and to provide unmistakable landmarks that could be followed easily by a pilot. Flight strips varied in size. The smallest -- 150 feet (46 meters) wide and 4,000 feet (1,220 meters) long with the length increased by 500 feet (152 meters) for each 1,000 feet (305 meters) of elevation -- were designed for tactical aircraft such as medium bombers. A larger flight strip could accommodate heavy bombers such as the B-17 and B-24, while still larger strips were designed for heavier classes of aircraft.

The benefits weren't expected to be entirely military. As MacDonald explained, "The close coordination of our highways and airways is becoming a vital necessity to assist the economic growth of this country."

In that spirit, Congress considered including a flight strip program in the Federal-Aid Highway Act of 1944 -- the law that authorized designation of a "National System of Interstate Highways." However, the 1944 act did not include the flight strip program."

That highways were built to serve as runways for wartime is a myth according to the federal highway administration

They often end up being replaced either by turning them into proper roundabouts or replacing them with other types of intersections as they don't have many of the benefits of modern roundabouts.

There are a couple other good reasons to ride farther out into the lane:

• It makes you more noticeable to oncoming traffic. Behind hit from behind is what most people worry about, but statistically, it's less likely to happen than seeing the car that hit you. Typically, they're turning and cut you off, not realizing that bikes go faster than 10 mph.
• Being farther away from parked cars reduces your risk of being doored.

Also, if I'm not using up the whole lane when I'm riding, I certainly do when I stop at the lights. Even if there's a bike lane, I'll often pull out of it so no car pulls up alongside. Cars do dangerous things when they start out alongside me; they'll pull just barely ahead of me and turn, cutting me off. Plus, you're naturally a bit wobbly when you're starting out, shifting your balance and clipping in to the pedals. Not a good time to have less space than usual.

I took a bicycle touring class last semester (hey, free credit hour) and they recommended doing this also. It really works - use up more of the lane and cars will realize they should be moving outside of the lane to pass you.

And to the people who say this is more dangerous - I don't believe that. The Crash-Type Manual For Bicyclists says in the "Motorist Overtaking - Misjudging Passing Space" that "almost 1 out of 5 bicyclists were on the shoulder or in a bike lane." That seems out of proportion to me. People rarely ride on the shoulder (see below) and bicycle lanes aren't that common.

As far as riding on the shoulder goes, no one actually does that around here. First of all, it doesn't even apply to in-town riding - there is no shoulder. Secondly, outside town the shoulder is usually a really crappy surface. I'm not taking my road bike on that.

Honestly, the technology exists right now to automatically drive my car along a freeway.

Carnegie Mellon's: No Hands Across America
UC Berkeley's platoon of cars at Demo '97

But this will never be a mainstream product in our society. Too many lawyers and other disinterested parties (such as insurance companies).

This is actually pretty close to the truth. This is a major reason why Adaptive Cruise Control is being sold by OEMs as a "convenience" feature rather than a safety benefit. Another major factor is that many of these systems rely on rather expensive sensors (from a car component perspective). Consumer willingness to plunk down thousands of dollars to enable their car with these systems is not present except for the luxury models.

Couple that with the fact the most municipalities get the much of their funding from... (wait for it) ... traffic fines and you have your tinfoil hat issue---that just happens to be true.

There were no private efforts to build an interstate highway system. That had to be left up to the federal government.

There is some infrastructure that private companies cannot provide, because it is very hard (some might claim impossible) to get a business model that produces a profit. This is very true in the case of the "last mile." Why would a private company want to provide service to only a few individuals if they lose money doing so? They answer they won't, which is why they have not.

The area that I live in is a prime example. Internet access is very available right around Virginia Tech's campus, but the further from campus that you get (mainly on the outskirts of Blacksburg), the harder it becomes to secure a high speed connection.

A friend of mine lives in a housing development on Brush Mountain (within the Blacksburg limits). His entire neighborhood does not have any method of securing high speed internet access other 1-way and 2-way satelite services. The physical lines (fiber to the telephone distribution node, and copper to all the houses) exists for DSL, but no service provider is willing to service such a small area, especially if they are only going to get a few subscribers at first.

Government is not a profit making venture. It should, and has in the past, facilitate the development of infrastructure. I understand that there are some inherit inefficiencies with building and maintaining infrastructure in this way, but at least this way, it gets built and maintained.

When was the last time traffic / bandwidth increased on the roads near you?

$15 billion / 161 lane-miles / 5280 (feet/mile) * 15 feet (average car length) = $264,680

"Intelligent highways" kill two birds with one stone -- surveillance of the public plus assauging the public the roads are safe despite the 42,000 annual U.S. fatalities.

If Microsoft Built Cars..

An interesting proposition.. /me peers into his crystal ball...

If Microsoft Built Cars...
If Microsoft Built Cars...
If Microsoft Built Cars...
If Microsoft Built Cars...
If Microsoft Built Cars...
If Microsoft Built Cars...
If Microsoft Built Cars...
If Microsoft Built Cars...
If Microsoft Built Cars...

Whoa.. stick with QNX, please.

(Many Highways were required by law to have a certain amount of space that could be used as a landing strip)

<trebek>Ohh, I'm sorry, that's incorrect</trebek>. Check here for the answer

(Many Highways were required by law to have a certain amount of space that could be used as a landing strip)

This is regrettably an urban myth:

US DOT document concerning this

Snopes document on it

Take all of the wires in the street, and all of the telco switch facilities and give them back to the people. Make the whole infrastructure of monopoly regulated telcos belong to the people who have paid for them. They are too valuable a resource to allow to remain in the hands of a few unscrupulous companies any longer. These companies were paid a GUARANTEED profit for decades. They actually made more money because they over-built their systems. Since we already paid for it, it is righfully ours.

A cool idea! I'm all for keeping government out of our lives, but, there are times when it's necessary. We own most of the roads, most of the water and sewage distribution and treatment facilities in the U.S., why not information distribution? Look at the Interstate highway System. That was a long-term project designed to enhance our infrastructure. This sounds pretty close, if not identical, to the digital information distribution troubles we're having now. A far-sighted approach to wider bandwidth distribution to the masses might be something that the government needs to get in on.