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We're excited about our new roundabout

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Re: We're excited about our new roundabout

#301

Earlier quoted context omitted.

The area borders wetlands and a very steep hillside where one of the roads intersects. And the regular flow of traffic pre-roundabout was more like 60-65 mph. A roundabout was the correct choice.

I'm not arguing about whether the roundabout was the correct choice. However, the department of transportation can eminent domain whatever they want. And neither hillsides nor wetlands are insurmountable for modern civil engineering.

Wetlands are highly protected. Hillside (which a road currently resides on) is expensive to “fix”.

Re: We're excited about our new roundabout

#302
post #126
post #123

Earlier quoted context omitted.

Just because you drove wrong does not make the roundabout bad. That would require you to compare accident numbers from before and after. I’m fairly certain the stats lean in favor of even terribly designed roundabouts.

> Just because you drove wrong does not make the roundabout bad. You seem to have misread my post. Everyone drove wrong. I seemed to be the only one to notice it, and started avoiding that roundabout, because driving with the correct right of way rules during busy times would lead you to t-boning another car. Other people I talked to said "no, that's just how you're supposed to drive on that roundabout" (it wasn't, a…

I think you missed my point due to me saying something about driving through the roundabout incorrectly. My apologies, that was entirely besides the point.

I’m trying to say that everyone driving through it incorrectly is not a great metric to judge bad roundabout. If everyone does it wrong and it’s still safer than a regular intersection, then is a success.

Of course I don’t know the numbers involved, so I can’t say if that’s the case here.

Re: We're excited about our new roundabout

#303
post #140

Roundabouts get a lot of praise whenever they're mentioned, and from a traffic flow perspective that's understandable - if by traffic you mean motorised traffic. For pedestrians and cyclists they are worse than the alternative (lights - or even a simple intersection) in my opinion. > Making a roundabout for everyone ctrl-f "walk", "cycl", pedes". Nothing.

Citation needed. As a cyclist I prefer roundabouts: they're faster than lights and don't rob my momentum, and they're safer than uncontrolled intersections/4-way stops because all the cars are coming from the same direction. Caveat: this is for simple, single-lane roundabouts. Multi-lane roundabouts are gnarly for cars and worse for cyclists.

Apologies. A bit of a blanket statement on my part. There are definitely examples of roundabouts built properly (where cyclists and pedestrians are considered first-class users). Sadly not that common in my experience.

Here is an example of the kind of thing I had in mind: https://maps.app.goo.gl/mexZWJ9ZP1yvEJ7k7

As you can see, they are building a pedestrian overbridge on the north side, but consider what you would have to do to traverse in any other place as a pedestrian (or get across anywhere currently). Here's a suggestion from Google (i.e. just pretend you're a car): https://maps.app.goo.gl/AiBoyWk4Z7bFr21z5

The above is in one of the busiest parts of this city. It's not like there are no people wanting to walk. In fact I found myself in exactly this position here not too long ago. I wanted to get from the mall side to a cafe on the opposite side. I gave up and ate a sad meal in the mall :(

Edit: Here's another example (with Google's hilariously impractical suggestion): https://maps.app.goo.gl/pati5dBBTnSgxZ1m9

Re: We're excited about our new roundabout

#304
post #17

Apparently I'm sticking my neck out here, but it really doesn't seem that hard. Overhead, I can intuit the path I would take, and if I imagine it first-person, it seems even more obvious. It's frustrating riding with certain other American drivers in other countries. I've met numerous folks now that seem upset that they have to actually pay attention to their driving and the traffic. Meanwhile I'm horrified that they…

No, you're definitely not the only one who likes them. Some folks complain about them when they first go in, but they tend to figure it out. WSDOT has been encouraging them for a few years now, and my town has several new roundabouts as a result -- and lots of other cities across the state are using them. They've made navigating those intersections way easier, reduced traffic "waiting times", and generally improved s…

I agree, Washington does seem to at least aspire to better roundabouts than some places I've heard of. The one rule I see to be truly necessary is "yield to oncoming traffic from the left."

I still get confused at the big roundabout in Kent, after coming off Highway 167 at Willis Street, but most others I've encountered are fine, despite the drivers who still want to stop before proceeding onto them even when there's no other traffic.

Re: We're excited about our new roundabout

#305

Earlier quoted context omitted.

>Even if they don't prevent all collisions, they turn T-bones into glancing hits No, they don't, at least not in America. When you let American traffic engineers design a roundabout, you get this: https://www.google.com/maps/@38.8643875,-77.2755474,583m/

As others have said ... that's not a roundabout. Here's one of my favourite hybrid "roundabout" junctions: https://www.openstreetmap.org/search?query=Boughton%20Heath%...

>As others have said ... that's not a roundabout.

American traffic engineers would apparently disagree with you.

Re: We're excited about our new roundabout

#306

Earlier quoted context omitted.

>Even if they don't prevent all collisions, they turn T-bones into glancing hits No, they don't, at least not in America. When you let American traffic engineers design a roundabout, you get this: https://www.google.com/maps/@38.8643875,-77.2755474,583m/

similar one here, but with added lights https://www.openstreetmap.org/#map=18/53.479432/-2.281970

The one I linked to in Fairfax County VA also has lights, though it might not be obvious from the aerial view. It's really a disaster of traffic engineering. It's probably the most complicated intersection I've ever driven through.

Re: We're excited about our new roundabout

#307
post #194

Earlier quoted context omitted.

> They definitely make traffic flow smoothly They make slow or medium traffic flow smoothly. If the traffic is heavy, roundabouts make everything worst.

Have you measured it?

No, I got that from a materials road engineers made available publicly a while ago when I was interested in the topic. It had whole bunch of various trade-offs you can make with intersections in it.

Re: We're excited about our new roundabout

#308

Earlier quoted context omitted.

I like 4-way stops as a pedestrian because I can actually cross the road there. With roundabouts it's impossible to cross without asking really nicely or risking my life. US drivers do not stop for pedestrians so crossing that kind of infrastructure is often taking your life into your hands.

Roundabouts should have only 1 direction you need to look at to cross. You don't have to watch 3-4 different directions like at a 4way stop. That said, if there's a huge bias towards cars coming from one direction (or out one direction), that can be very difficult to cross. And it has impacts on the roundabout's throughput too, and means that a roundabout might not be the most ideal. Similarly to how a roundabout tha…

> It has impacts on the roundabout's throughput too

For these use cases there's the turbo roundabout[0]. Depending on how you design it you can give certain directions slightly more priority, though they don't solve the pedestrian issue either.

[0]https://en.wikipedia.org/wiki/Roundabout#Turbo_roundabouts

Re: We're excited about our new roundabout

#309
post #307

Earlier quoted context omitted.

Have you measured it?

No, I got that from a materials road engineers made available publicly a while ago when I was interested in the topic. It had whole bunch of various trade-offs you can make with intersections in it.

Can we see it?

Re: We're excited about our new roundabout

#310
post #296

Earlier quoted context omitted.

Right before left is how four-way stops work. Putting the signs up doesn't cost much, so why skip them?

No, that’s not the same. On a 4-way stop you have to completely stop. Also how I remember my year in the US (I’m from NL) is that the first to reach the stop has right of way, not the “left” one. But I might be wrong on that last one? Didn’t have a drivers license at the time (but was surprised - and turned off from - 4-way stops).

That's how it works in my state. The right before left thing is just the tie breaker.
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