Can We Fight Carbon Emissions With Roundabout Intersections? (seattletimes.com) 303
The U.S. city of Carmel, Indiana (population: 102,000) has 140 roundabouts, "with over a dozen still to come," reports the New York Times. (Alternate URL here.) "No American city has more. The main reason is safety; compared with regular intersections, roundabouts significantly reduce injuries and deaths.
"But there's also a climate benefit." Because modern roundabouts don't have red lights where cars sit and idle, they don't burn as much gasoline. While there are few studies, the former city engineer for Carmel, Mike McBride, estimates that each roundabout saves about 20,000 gallons of fuel annually, which means the cars of Carmel emit many fewer tons of planet-heating carbon emissions each year. And U.S. highway officials broadly agree that roundabouts reduce tailpipe emissions. They also don't need electricity, and, unlike stoplights, keep functioning after bad storms — a bonus in these meteorologically turbulent times.
"Modern roundabouts are the most sustainable and resilient intersections around," said Ken Sides, chairman of the roundabout committee at the Institute of Transportation Engineers...
A recent study of Carmel's roundabouts by the Insurance Institute of Highway Safety found that injury crashes were reduced by nearly half at 64 roundabouts in Carmel, and even more at the more elaborate, dogbone-shaped interchanges... [V]ehicular fatalities in Carmel, according to a city study, are strikingly low; the city logged 1.9 traffic deaths per 100,000 people in 2020. In Columbus, Indiana, an hour or so south, it was 20.8. (In 2019, the national average was 11.)
The Times points out other advantages — they can also be more friendly to pedestrians and cyclists, and alleviate rush-hour backups. But Carmel's former city engineer just argues it's an improvement over an older roadway system which "doesn't put a lot of faith in the driver to make choices.
"They're used to being told what to do at every turn."
"But there's also a climate benefit." Because modern roundabouts don't have red lights where cars sit and idle, they don't burn as much gasoline. While there are few studies, the former city engineer for Carmel, Mike McBride, estimates that each roundabout saves about 20,000 gallons of fuel annually, which means the cars of Carmel emit many fewer tons of planet-heating carbon emissions each year. And U.S. highway officials broadly agree that roundabouts reduce tailpipe emissions. They also don't need electricity, and, unlike stoplights, keep functioning after bad storms — a bonus in these meteorologically turbulent times.
"Modern roundabouts are the most sustainable and resilient intersections around," said Ken Sides, chairman of the roundabout committee at the Institute of Transportation Engineers...
A recent study of Carmel's roundabouts by the Insurance Institute of Highway Safety found that injury crashes were reduced by nearly half at 64 roundabouts in Carmel, and even more at the more elaborate, dogbone-shaped interchanges... [V]ehicular fatalities in Carmel, according to a city study, are strikingly low; the city logged 1.9 traffic deaths per 100,000 people in 2020. In Columbus, Indiana, an hour or so south, it was 20.8. (In 2019, the national average was 11.)
The Times points out other advantages — they can also be more friendly to pedestrians and cyclists, and alleviate rush-hour backups. But Carmel's former city engineer just argues it's an improvement over an older roadway system which "doesn't put a lot of faith in the driver to make choices.
"They're used to being told what to do at every turn."
The problem with these in the US (Score:5, Insightful)
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Sounds like US drivers are on average dumb as shit if they cant work out roundabouts, they shouldnt have a licence.
Re:The problem with these in the US (Score:5, Interesting)
A friend of mine recently moved to the US. Over the years he had tried and failed to pass his driving test here in the UK. When he took his test over there, he passed first time.
He commented that the driving test there is so easy it's dangerous.
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Re:The problem with these in the US (Score:4, Informative)
I'm sorry, what? That was literally the first practical lesson when I took my license in Denmark. Yes, LESSON, not EXAM.
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Road test requirements vary from state to state. Yes, they're all way too easy, but your experience isn't universal.
Re:The problem with these in the US (Score:5, Insightful)
at my driving test (around 10 years ago in CA), there was no parallel parking, no traffic cones, not even U-turns -- just 20 minutes of driving around, with a single stopping at the curb. to me the DMV's approach to driving appeared to be "we'll give out licenses to anyone who barely qualifies and then we'll take them back if they cause too much trouble on the road". given my following experience driving (main in the Silicon Valley area and the rest of CA), that approach may have been working out better for them than it looks on paper. and, there were very few roundabouts there though; most T-intersections in residential areas were 4-way stops, so I'm not surprised US drivers unused to roundabouts would treat them similarly.
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Re: The problem with these in the US (Score:5, Insightful)
trusted to send a 1-ton vehicle down a motorway
Wow! I haven't driven a 1-ton vehicle since my '63 Volkswagen.
Re:The problem with these in the US (Score:4, Funny)
I don't have any vegan recipes.
My oven isn't big enough to cook one.
US Driving Test (Score:5, Interesting)
He commented that the driving test there is so easy it's dangerous.
US driving tests are a joke. When I moved there years ago with my UK license they first made me take a theory test which the guy behind the desk thought I had cheated on because I got all the answers right even though I had just taken the test sitting in front of him.
The driving part was a joke consisting of driving around one block in an automatic. The "hardest" thing was turning left back into the parking lot. In the UK examiners can cut the test short if you do something that causes you to fail and, since my test was so short I asked the examiner what I had done to fail it. She looked at me shocked and told me I had passed!
The scary part though was that this was in Illinois and at the time there was a big scandal that the licensing agency had been accepting bribes to hand out licenses without tests!
Re:The problem with these in the US (Score:5, Interesting)
The reverse of this is if like me you come a country with no 4 way stops and no road rules that rely on time of arrive the first time you encounter a 4 way stop it is a bit unnerving. You worry about what if you arrive at the same time as another car? So you try to adjust you speed so you can be sure you arrive at a different time to anyone else, yuk! I wonder how many accidents are simply conflicting claims about who was there first? With roundabouts you only have to worry about traffic from one direction whereas with a 4 way stop you have watch three directions at the same time.
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Most countries have rules how to handle a 4 way intersection.
I'm only aware about the US having the "stupid none rule" that the one has right of way who is there first.
In most of Europe the car coming from the right (of you), has right of way. Regardless if any other one was "first".
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If four cars are at the intersection, all four have a vehicle on their right, so none have the right-of-way.
The American system of first-come-first-go makes more sense.
Re: The problem with these in the US (Score:2)
A roundabout, when driven correctly, is a first-come first-go without having to watch for traffic from multiple directions.
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If four cars arrive at once, you can still do first-come first-go, and the rest will resolve itself by the yield rule.
Right. That's why first come, first go is a good rule.
A roundabout, when driven correctly, is a first-come first-go without having to watch for traffic from multiple directions.
Yeah, but you still have to look the other way for pedestrians or cyclists, who may be doing something stupid.
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Am I missing some joke here? GP says, "If four cars arrive *at once*". How the heck does it lead to FIFO?
Cross-traffic turns yield, so in a right hand driving country for example any straight through traffic goes first, then any right turns, then any lefts. It doesn't FIFO, it just resolves by the other rules. It's only when two people are crossing one another's paths by going straight that you actually FIFO at a four way.
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That's now how roundabouts work. If they all arrive at the same time then they can safely enter the roundabout at the same time too.
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In Ireland, Malta and Cyprus, you give way to the right. i.e. to the traffic already on the roundabout or going from the right who will cross your path if you try to enter it. Surely most/all of the others give way to the left? Where do people on the roundabout give way to vehicles who want to enter it?
Re: The problem with these in the US (Score:3)
Re: The problem with these in the US (Score:3)
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I'm not mistaking anything.
And pointed out you have a silly rule in the US.
You are mistaken about what the US rule is.
Nobody cares if your excuse for being stupid is that you're a drunk.
Europeans often have this pathetic type of nationalism where you're quite sure that Americans don't understand something and have no rules, but you're simultaneously incapable of understanding the American rule because it is too complicated for you. Even though it is something simple that every idiot over here can understand. You've simply loaded up conflicting hyperbole into your little heads,
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Then the city started allowing left turns while pedestrians could still be in the crosswalk. The next day a driver hit a pedestrian who ended up in the hospital.
Do drivers always assume they have the right to run over pedestrians in your country? Because in most countries, no matter what the signs or traffic lights say, if a pedestrian is on the road you must not run him over.
Re:The problem with these in the US (Score:5, Informative)
Sounds like US drivers are on average dumb as shit if they cant work out roundabouts, they shouldnt have a licence.
i can assure you, the average U.S. driver is dumb as shit, regardless of roundabouts.
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Sounds like US drivers are on average dumb as shit if they cant work out roundabouts, they shouldnt have a licence.
I live in a tourist town which, though rural, is all roundabouts. Many of the people who stop before entering one, despite the plain Yield signs, are visitors from roundabout-intensive European countries that sometimes mandate a stop before entering.
The real problem is that at least in Arizona, roundabout drivers are not required to signal turns. So when you see approach a roundabout and there is traffic on the opposite side, you have to wait to make sure that person is not executing a left turn. This adds
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Re: The problem with these in the US (Score:5, Informative)
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Also, if the traffic coming into the roundabout is unbalanced, people can get stuck.
Imagine a roundabout with 4 exits A,B,C,D. If there is a lot of traffic going from A to C, traffic going from B to D will just get stuck, unless there's traffic going from D to B.
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It doesn't really stop, at least not worse than any other type of intersection. What happens is that the roundabout gets packed and people use zipper merge to let everyone (slowly) join it as people get off.
The only issue is if one exist is at a complete standstill, then that will prevent everyone from moving at all.
Wrong Design? (Score:2)
That sounds like they were designed wrong, perhaps because there wasn't enough space to build them properly. In a proper roundabout intersection, there's an island in the middle that prevents you from clearly seeing across the roundabout, and forces you to treat your entry into the roundabout as if you were merging into a road.
Where I live, we have lots of these. We also have lots of drivers that don't know how to navigate
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This. It's just a circular one-way road with yield signs on the entrances. It's not that hard to understand if you draw it large scale.
It kind of breaks down when they try to build them into very small intersections though (I've seen them take small 4-way stops and then just plunk a concrete circle in the center of the intersection).
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The UK has mini-roundabouts. They're literally a painted white circle in the middle of the junction.
Actually they work pretty much like a 4-way stop (or more like a 4-way yield, you don't have to stop if there's no other traffic), but traffic on your right (left in the US) has priority rather than whoever arrived first.
And if you want confusing, look at the Magic Roundabouts. Roundabouts made of smaller roundabouts! Though they're not as confusing as they look.
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They're kind of great for intersections without a lot of traffic. In most cases you don't have to stop, where before you would have to stop.
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> It's not rocket science.
Hell, even rocket science isn't rocket science. Rocket engineering, on the other hand ... https://www.nasa.gov/mission_p... [nasa.gov]
Re:The problem with these in the US (Score:4, Informative)
Confused? They would be. Obligatory links to the UK's (5 way) "Magic Roundabouts":
https://www.youtube.com/watch?... [youtube.com]
https://www.youtube.com/watch?... [youtube.com]
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Is the average driver doesn't know how to navigate them properly.
They put one of these in my home town a few years ago. It even had a pretty little fountain in the middle of it. I drove through it a year or so ago. You can still see the outline of the roundabout but the statue is gone an has been pounded flat. It's now a four way stop. I don't know what happened but I bet it involved a drunk redneck, a big ass truck, and 1 am.
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No (Score:3, Interesting)
We cannot.
ROFL (Score:3)
Here in the UK, the planners seem hell-bent upon making things worse at roundabouts. They are putting traffic lights in on many that very much don't need it. Many have the lights operational 24/7 but there are only queues at peak times. Will they put in peak-hour only lights? Is the Pope a Catholic?
Enjoy your little bit of freedom. The planners in their quest to stop traffic at all costs will soon be along with the stop and don't go lights.
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Enjoy your little bit of freedom. The planners in their quest to stop traffic at all costs will soon be along with the stop and don't go lights.
We don't even need the planners to do that in some cases. There are areas where circles are actually objectively worse than lights. And they put them in anyway, because the stupid federal / state governments say they have to replace 4-ways with circles or they lose grant funding.
Like in the city I was in from 2014-2017, they had a circle that was part of the entrance / exit system on a six lane highway, going to two roads, a four lane and a two lane service road ( with two lanes from the circle merging to a
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Roundabouts only have limited capacity before they reach gridlock. I imagine that where they are putting in lights, traffic has risen to the level where they are necessary for at least part of the day.
Friendly to pedestrians and cyclists ?!? (Score:3, Insightful)
First, let me say that I think roundabouts are fine for cars and they've been in widespread use in my country for several decades.
But consider the pedestrian who has to walk to the other side: you now have to walk around the entire thing and some are very large. No big deal but it can easily take an extra minute.
Now for the cyclist, simply observe that many will prefer to take the pedestrian crossing instead of staying on the road even though they now have to stop instead of having the priority while on the inner part of the roundabout. Why is that ? Because it feels very unsafe to be on the outer diameter of the roundabout on a bike. The cars inside go fast and look towards the inside (not your direction). And the cars coming in barely look before inserting; many wouldn't even notice a bike. It's just scary.
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Usually, roundabouts have crosswalks on each exit, so I'm not sure why you're walking around the entire thing. Also, as a pedestrian, you now have the right of way, so instead of pushing a button and waiting for the right to turn green, you can just cross the street much more quickly.
Your arguments are against roundabouts without bike lanes (which, fair enough). But then you should argue for bike lanes, not against roundabouts.
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Roundabouts are just better. (Score:4, Interesting)
We have both in the UK, both roundabout and traffic lights. I have been driving for over three decades in the UK and abroad and Roundabouts are just better in every way.
Re: Roundabouts are just better. (Score:4, Insightful)
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But the road planners/engineers have to get them right.
Roundabouts only work if the traffic flow is not so high as to cause some inputs to get locked out, because the ring is always full of traffic. This leads to some UK roundabouts having traffic lights put in so as to give everyone a chance. Then you're back in the "vehicles wasting fuel idling whilst they wait for the lights" situation.
You can compromise by only having the lights active at the busier times.
Also the mini-roundabouts can all too
Idle emissions is old news (Score:2)
For most new cars emissions at idle is already a solved problem. Obviously EVs will completely shut down the engine. Hybrids do that as well. But since last five years or so, regular gas engines will also shut down at idle.
I remember seeing a study where they measure idling for more than 15 seconds is more expensive than an engine restart. So your Mazda will just shut down engine and restart when you hit gas.
No need to install roundabouts, if this is your only concern.
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>it used to be the rule that most engine wear occurred when first starting the engine.
that is from the metal-on-metal contact after the oil drained off the engine.
Two factors for on./off engines:
1) They aren't usually stopped long enough for the oil to largely drain off, and
2) the increased use of synthetic and semi-synthetic oil: synthetic clings to the metal longer than natural oil.
I know that my '02 Ford E150 required *proof* of not just scheduled oil changes, but semi-synthetic. I would suspect tha
The UK is full of them... (Score:5, Interesting)
The benefits over traffic lights are absolutely there, but there's downsides too - as there is for everything.
One of the obvious ones is retrofitting roads and real estate.
So, over here in the UK, we have some exceptionally large traffic islands and some incredibly complicated sets of them, that do keep the traffic flowing, but can be ... interesting to navigate.
We also have some ridiculously small ones, due to the aforementioned "real estate" "retrofitting" issues.
To all intents and purposes, these end up being more like stop signs at an intersection.
There's a busy road intersection near where I live, where 4 roads converge at odd angles (yeah, this is classic Britain), that has two tiny traffic islands positioned right next to each other - and you have to work out all the give-way to right rules.
What tends to happen, is people just randomly forge ahead, but somehow, it sort of works. No idea how.
Folk often just ride right over the edges of the small ones, because, quite frankly, they are ridiculously small.
There's some quite famous traffic circle (roundabout) intersections in the UK, that just boggle the brain the first time you navigate them.
And this is where the design can go all sorts of wrong - just look up Swindons "Magic roundabout", an insane layout of 5 mini roundabouts in a circle.
There's also the very real possibility of getting completely lost in some UK towns, due to the size of some of the roundabouts and the sheer volume of them. If you are not used to them, you are not only trying to navigate fast moving traffic converging into numerous circles, but also trying to figure out the road signs - sure, sat nav has changed this to a degree, but before sat nav, one town in particular that cooked my noggin' for a good few weeks, was Basingstoke.
For those not used to these measures to keep traffic flowing, it can be really confusing and intimidating at first, depending on your outlook.
If you are gung-ho and don't give a shit, hell, just blast into them full throttle.
When they work in the way intended, this approach works - just a quick glance to the right, all clear, keep moving.
Re: The UK is full of them... (Score:2)
I've since moved to New Zealand. People here aren't as good as the British at roundabouts and often indicate incorrectly. But they still help traffic flow better than traffic lights.
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From your description, traffic works despite several of these types of roundabout. That's not an endorsement of them at all.
Roundabouts are great where there's room and very little traffic flow, and you're not trying to manage traffic coming in and out of intersections at the same time. Otherwise they are senseless.
Most of the time a simple 2-way stop at a 4-way intersection achieves essentially the same goal though, because usually one direction has a lot more traffic than the other.
Here in the USA we keep
Great, in the right situation (Score:2)
Carbon (Score:2)
When all cars passing these roundabouts are electric, when all energy used in the USA is green, we still have to reduce the amount of CO2 in the atmosphere. This helps but it is not nearly enough
The US is *decades* behind in road engineering (Score:4, Informative)
The roundabout diagram in TFA is roughly what has been standard in Europe for the past 50 years (Nantes built the first "modern" roundabout in France in 1971, copying an earlier design from Britain. Can't remember how old the British design was). Now don't get me wrong, there are a lot of good things about roundabouts, namely car safety. They almost *eliminate* the risk of head-on collisions (the type you get on left turns). They transform massive crashes into fender-benders. That's a *massive* win.
On the down side, they take a lot of real estate. Shouldn't be an issue in North American suburbia though. And the freeflowing nature only works up to a certain point, they're not silver bullets.
The big downside is that the design in TFA is *terrible* for cyclists with lots of blind spots, and not enough traffic calming. Dutch designs favor pedestrians and cyclists (they have priority all over) by giving them enough room from car traffic to be visible. Other features *force* drivers to slow down more while still being freeflowing. Just google "dutch roundabouts", there are plenty of explanations and diagrams, videos on youtube, etc.
The bit about emissions seems backwards to me: people MUST drive less if you want any meaningful impact (pick any of: shorter trips, fewer trips, bike/walk/transit to work/school) No roundabout will ever fix the environmental hell hole that car-centric suburbia is.
Exercise in turd polishing (Score:2)
I'm sure roundabouts, diverging
Spiral roundabouts FTW (Score:2)
https://i.imgur.com/xnOFp8N.png [imgur.com]
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can confirm.
The A3 -M25 junction near London is a spiral. You have to try really hard to end up in the wrong lane if you enter it correctly.
Depends on the situation (Score:2)
So much depends on the specific intersection, and the amount of traffic. For intersections with small-to-moderate amounts of traffic, roundabouts are fine. Better than traffic lights or four-way stops, because there is very little waiting time and often no need to stop at all. Which is the point.
For intersections with lots of traffic, a roundabout has to be a huge multi-lane affair, and those are just a mess.
Why do you need studies? (Score:2)
UK roundabouts (Score:3)
Have a go at a simulator! (Score:2)
https://traffic-simulation.de/roundabout.html
Probably a poor choice of argument. (Score:2)
Regardless of the benefits of roundabouts, which are not universal (and must be integrated into a very complex and holistic road network design), the choice here to use fuel savings and reduced greenhouse gases is a poor one.
The numbers quoted here for the reduction in annual fuel use are a fraction of a fraction of a percent of the yearly fuel use of vehicles.
Roundabouts make sense in certain places. Sometimes, they are terrible, and sometimes they are so terrible that the roundabout itself has numerous st
My NIGHTMARE UK driving story (Score:3, Interesting)
On holiday, I drove from Glasgow to London over a week, and had a chance to experience every type of roadway. As many have commented here, roundabouts are useless once traffic reaches a certain flow rate. More than once I experienced the monstrosity of an intersection of two primary roadways in the UK regulated by roundabouts: you take two roundabouts, place them side-by-side in an oval 3 lanes wide, and then add stoplights at every access point. I still wake up in a muck sweat over those.
On a secondary road with irregular traffic, they're a nice solution. On a tertiary road with no traffic, they're an annoyance, totally unnecessary. If no one is ever going to be waiting for more than just a moment, just have the roads cross one another. Done and done.
What really made driving nightmarish, however, is that there is apparently no off-street parking in the entire country. You come up to your typical village, and people have to cram their cars literally anywhere they can, even half-way out into the lane if they have to. It's Demolition Derby time, weaving in and out until you get through the town center.
Even this would be acceptable if the roads themselves were wide enough for modern travel, but they're not. Aside from the excellent first tier highways, every road is too narrow by about 4-6 feet. The loss of even a few feet of clearance on the sides makes for an incredibly alarming driving experience. It's not an issue when you're driving down some country lane, of course one expects that to be narrow. No, it's driving through major traffic with mere inches of clearance at high speed. Still gives me the willies.
Not to mention that it rains sometimes in the UK.
Yeah, a pretty unforgettable experience. I was enormously relieved to not have to deal with this once I got home.
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Clue stick: If the junction is controlled by traffic lights then it is not a roundabout.
I've been driving in the UK for over thirty years and true roundabouts are brilliant for keeping the traffic flowing with competent drivers who can merge with confidence.
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It's not a roundabout if it has traffic lights? I don't see how changing the name changes its fundamental design. The intersection is still round. You still have to keep your eyes on traffic entering and leaving the circle, only now you have the additional complexity of a traffic light to watch for.
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It has has nothing to do with the name.
If it has traffic lights it is not functioning as a roundabout, so it will not get the benefits of integrating the flow.
The evidence, actually included in the article show that roundabouts actually function better.
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Nah roundabouts are more effective, even traffic light controlled. You don't have to stop oncoming traffic entirely to cope with cars trying to cross, and head on collisions are almost impossible.
But yes we have small roads which largely predate the car. If you think London to Glasgow is fun as a drive, yet heading, well, pretty much anywhere in/around/across the south circular in the afternoon. Especially Tooting Bloody Highstreet. Hours of boredom stopped in traffic interspersed with minutes of terror whe
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Both systems are obviously crap, and one can only argue about which flavor of crap tastes worse here.
Tiny roads not big enough for cars with cars on them are crap. So are gigantic roads with tons of super fast, super powerful cars with idiots behind the wheel.
Frankly, the roads are the big problem, we can do better today
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apparently no off-street parking in the entire country
Yes, there is a lack of off-street parking, but we have these things called 'double yellow lines' on the side of the road that mark where you can stick you car in such towns. These tend to prioritise access based on how pretentious and outlandishly sized your vehicle is. They are usually in the most convenient locations - directly outside schools, busy shopping streets, hospitals etc. You can also just park on the pavement - folks here are very polite and pedestrians are happy to walk in the middle of a bus
Re: My NIGHTMARE UK driving story (Score:3)
I never really noticed the roads being narrow, I just thought they were very wide in other countries.
Driving in the UK was fun: country roads, quite often with hilly sections, and because it's an old developed country there are so many alternative routes to every destination.
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Agreed, I certainly enjoyed driving outside of town centers, the countryside is beautiful and so much fun to drive through. Every trip was a journey.
Just thought I'd throw that in there (Score:2)
The reason that Carmel has so many roundabouts is Brainard, the city’s seven-term Republican mayor.
If the story was instead about how he had boiled puppies for breakfast, that would be the lead /. pull quote, lol
Won't Happen if it Reduces Traffic Fines (Score:3)
Red light cameras are a cash cow
One downside to roundabouts (Score:3)
One downside to roundabouts (at least from the point of view of city governments) is that you no longer get all that sweet sweet revenue from red light camera fines...
Temporary gain only (Score:3)
Because modern roundabouts don't have red lights where cars sit and idle, they don't burn as much gasoline. While there are few studies, the former city engineer for Carmel, Mike McBride, estimates that each roundabout saves about 20,000 gallons of fuel annually,
That's great for fuel cars. But what about electric cars, which all vehicles will be eventually?
For electric cars there is no penalty for stopping... meanwhile the extra friction on tires created by going around a roundabout will mean tires will have to be replaced more often on electric cars then they would be on a straight intersection, thus emitting more CO2 over the long run.
No Red Lights? Come to the UK. (Score:3)
Because modern roundabouts don't have red lights where cars sit and idle
In the UK we have plenty of roundabouts with traffic lights, almost invariably where the roundabout is just off a motorway junction. They seem to be programmed to turn red as a car approaches, even if there is no other traffic around - I understand it is meant to be "calming" but it is actually infuriating.
Re: Sorry, but no. No roundabouts please. (Score:5, Insightful)
Why would you need to be able to read minds to use a roundabout? I suspect you haven't really got much experience of them. They are trivially simple to use - if there is traffic coming around it, towards you from the right (presumably the left in the US), you give way, and when there isn't you can join. Using a roundabout only requires your own very basic observation skills, no mind reading required.
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They are trivially simple to use
Maybe if the drivers around you have half a brain. On normal intersections, you have right before left. When entering a roundabout, that changes to left before right. It is scary to see how few drivers get the distinction right.
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* If they have a right turn signal on, I know they're about to leave the roundabout and it's safe for me to step in.
* If they have a left turn signal on, I know they're about to continue on the roundabout, crossing my path, and hence it isn't safe for me to step in.
* If they have no turn signal, I don't know what they are about to do, and I will often wait unnecessarily.
Re: Sorry, but no. No roundabouts please. (Score:2)
In the UK drivers are taught not to rely on other people's indicators (as we call them, which is a good way to think of them - they only indicate an intention, they don't gaurantee it). You never pull out in to the potential path (or actual path, obviously) of another driver, you wait until they are committed, i.e. that have at least started to move off the path you want to pull out in to. I'm not saying everyone does all the time of course, but that's what's taught and expected (i.e. in the case of an insu
Re: Sorry, but no. No roundabouts please. (Score:5, Insightful)
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Roundabouts take up more real estate, so the construction may not be cheaper. However, they are better in just about every metric, you just read how they significantly reduced the likelihood of death. You put your life in the hands of other drivers every time you cross a green light. At least in a roundabout they canâ(TM)t blow past the red light at 80+mph and are bending towards you so it isnâ(TM)t a direct T-bone. Sorry, but after reading the summary, even if your prior knowledge about roundabouts was absolutely zero, you would have to be an imbecile and a dumbass to just have made the whole safety argument against roundabouts.
They don't feel safer though. I fully grant the statistics of them being safer. I just wish they felt safer.
Can't help but wonder if some of the safety benefit is from everyone slowing down due to uncertainty.
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Well, I mean, that's not really true. They need more space than a simple red light intersection, so it's not obvious that they "reduce infrastructure." They are cheaper, though. They also reduce wait times, injury accidents, and congestion. Those aren't really opinions, these are measurable things.
Then you should be in favor of roundabouts, because properly designed roundabouts prevent drivers from just driving full-
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Have you ever used an intersection with stop signs? If you have, then there it’s about knowing how to use it, and giving the appropriate priority based on arrival. If you arrive at the same time, then what happens next will be a mix of who takes the initiative first and politeness.
In many ways a roundabout is the same, in that once you understand which vehicle has priority it isn’t complicated. Traffic entering the roundabout gives way to traffic already going around and if there are multiple l
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I've never heard anyone say that roundabouts are "un-american." I've only heard people complain that others think roundabouts are "un-american."
Now the metric system on the other hand, that's unamerican.
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On a roundabout all cars have to almost stop while in straight intersections only the cars from the side street need to stop.
Depends on the roundabout, and particularly on its size and shape.
Once one street has significantly more traffic, a straight intersection with priority road and a side street is better as it slows most drivers down much less.
In that case the street with most of the traffic would hit the round about tangential, problem solved.
In Europe, most roundabouts are ideologically motivated
Re:Roundabouts are only better ... (Score:5, Informative)
only better on intersections with low traffic from both directions.
That is just wrong, roundabout are better on junction with very high traffic because it keeps both directions flowing.
On a roundabout all cars have to almost stop
No they do not. Cars only need to slow, which makes merging easier because vehicle density is higher a lower speeds.
We have both in the UK and roundabout are very much better than traffic lights when there is enough room for them.