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Remove left turns for less dangerous city traffic

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Re: Remove left turns for less dangerous city traffic

#161

Post by StanislavPetrov »

burlesona wrote: post #51

One of the best ways to eliminate left turns is to replace four way intersections with roundabouts. This has the advantage of working even where there isn’t a grid to facilitate the “3 right turns” strategy. For a great description of why this is so effective, see the recent freakonomics podcast: https://freakonomics.com/podcast/roundabouts/

My lengthy driving experience in and around the New York area has more than convinced me that widespread inability to merge would make roundabouts here extremely difficult to implement. The few that do exist are usually littered with people who have stopped completely or are trying to cut across three lanes of traffic because they don't know what they are doing or where they are going.

Re: Remove left turns for less dangerous city traffic

#162

Post by drran »

Lammy wrote: post #151
drran wrote: post #146

Earlier quoted context omitted.

Why not just extend a light rail system to suburbs? It will be much faster to have point-to-point rail than car + rail.

> Why not just extend a light rail system to suburbs? The question we should be asking is more like "why did we tear them all up"? Lots of US metro areas did have this until demographics changed in the mid-20th-century and anti-growth/anti-housing/anti-mobility mindsets took over. You see it in eastern cities, like the Cincinatti Subway that was canceled forever in 1928: https://en.wikipedia.org/wiki/Cincinnati_Subwa…

I'm an engineer from Europe. I have an idea of a light suspended rail for point-to-point transportation (personal public transportation). It should be divided into two main parts — 1) high speed, high performance network for city, and 2) low speed, low performance, but low cost and low maintenance network for suburbs. I'm not sure is my idea viable, because, IMHO, it should be already developed in the USA long time ago. :-/

Re: Remove left turns for less dangerous city traffic

#163

Post by ygra »

MarcScott wrote: post #123
toast0 wrote: post #80

Earlier quoted context omitted.

Roundabouts in the busy city center would be terrible. Where roundabouts fit best is in intersections with low demand, because they have low capacity, and there's no reasonable way to increase capacity. If it's the urban core busy city center where there are skyscrapers right up to the lot line, there's no room for a roundabout unless you're willing to make 'round a bumps' or carve some footprint out of the buildings…

You should visit the UK and get a native to drive you around some city centres. We have the full range of roundabouts from massive, traffic light controlled, multi-lain and chain-linked junctions, down to tiny roundabouts that are little more than a circular bump in the road. It's rare that I stop at a junction that requires me to cross a traffic flow, lights or no lights, that I don't wish that a roundabout had been…

> I'm quite accustomed, in my area, to following a cyclist around a roundabout, paying attention to their hand signals, and giving them plenty of space.

As a cyclist, sometimes in roundabouts, this is something that many drivers need to be more aware of. In particular, depending on the roundabout size, the entry angle, and the car, someone's A pillar may completely obscure a cyclist.

Also, while a great solution for cars, in populated areas, roundabouts can be tricky for pedestrians to cross. Also not aided by the fact that at least in Germany many motorists have no clue about the exact rules (yield to crossing pedestrians and cyclists when exiting the roundabout because that's effectively a turn). The best solution in this regard still seems to be to put zebra crossings all around the roundabout, along with traffic islands between the lanes entering and existing the roundabout. That makes it sufficiently safe for people and bikes to cross and sufficiently obvious to drivers how to behave. But that takes even more space.

Re: Remove left turns for less dangerous city traffic

#164

Post by Doxin »

orthoxerox wrote: post #81
alksjdalkj wrote: post #68

Earlier quoted context omitted.

I'm a little skeptical that it would be safer for pedestrians and bikes. Bikes need to merge with traffic already in the roundabout instead of simply going straight through an intersection, and pedestrians would need to always check for oncoming cars rather than being able to mostly rely on lights telling them when they can cross. But then most of my experience with roundabouts is with large, multilane roundabouts so…

Proper Dutch-style roundabouts have the path for cyclists that follows the sidewalk, not the car lane. https://commons.m.wikimedia.org/wiki/File:Alternative_dutch_... Multi-lane intersections on major roads should just have a left-turn lane with a separate signal phase.

This is incorrect. To a rounding error all the roundabouts I have encountered (in the Netherlands, where I live) have the cycle lane follow the car lane, and give cyclists right-of-way over the cars. You'll occasionally see one where the cycle lane is separated from the roundabout, but I only know of one from the top of my head.

Re: Remove left turns for less dangerous city traffic

#165

Post by whalesalad »

burlesona wrote: post #51

One of the best ways to eliminate left turns is to replace four way intersections with roundabouts. This has the advantage of working even where there isn’t a grid to facilitate the “3 right turns” strategy. For a great description of why this is so effective, see the recent freakonomics podcast: https://freakonomics.com/podcast/roundabouts/

Roundabouts are great when people know how to use them to their full effect. They are beginning to become more common in the US but no one knows how to use them. People will treat it like a four way intersection until it is completely empty. Drives me nuts.

Re: Remove left turns for less dangerous city traffic

#166

Post by whalesalad »

The Michigan Left is such a great concept. Instead of turning left, you turn right and every boulevard has tons of dedicated u-turn lanes. So to go right, you turn right easy peasy. To go left, you also go right and then make your way to the left lane where you will be able to turn around and go your desired direction. There are so many of them that if you miss the one you want, there will be another a hundred feet down the road. It’s great.

https://en.m.wikipedia.org/wiki/Michigan_left

Re: Remove left turns for less dangerous city traffic

#167

Post by HeadsUpHigh »

burlesona wrote: post #51

One of the best ways to eliminate left turns is to replace four way intersections with roundabouts. This has the advantage of working even where there isn’t a grid to facilitate the “3 right turns” strategy. For a great description of why this is so effective, see the recent freakonomics podcast: https://freakonomics.com/podcast/roundabouts/

I live close to a place that has only roundabouts and zero intersections. It's just terrible. Very easy to congest and once the congestion reaches the previous roundabout it's game over. Everything stops.

Re: Remove left turns for less dangerous city traffic

#168

Post by goodpoint »

SideburnsOfDoom wrote: post #29
goodpoint wrote: post #23

Earlier quoted context omitted.

Once again, a clear warning that an article is US-specific would be nice.

Agreed. Advice to "avoid left turns " is not directly applicable to "drive on the left" countries.

In many countries such turns are either not dangerous or avoided using roundabouts.

Stroads exist almost only in US.

https://www.strongtowns.org/journal/2018/3/1/whats-a-stroad-...

Re: Remove left turns for less dangerous city traffic

#169

Post by fitzie »

when I lived on California i was amazed at how many pedestrian deaths there were in San Francisco, a city mired with no left turn rules. they allowed right on red, which I think contributed. I think most traffic engineers know about the green wave and improving traffic flow, but the political mission is to slow traffic to save lives and encourage mass transit. it's a shame

Re: Remove left turns for less dangerous city traffic

#170

Post by aliasEli »

burlesona wrote: post #51

One of the best ways to eliminate left turns is to replace four way intersections with roundabouts. This has the advantage of working even where there isn’t a grid to facilitate the “3 right turns” strategy. For a great description of why this is so effective, see the recent freakonomics podcast: https://freakonomics.com/podcast/roundabouts/

I you want to see a country that appears to be extremely fond of roundabouts, you should come to the Netherlands. In the past 20 years a high proportion of crossings has been replaced by roundabouts.

We do not always have sufficient space, especially in city centers. The normal solution there is to make traffic one-way only. I do not know if they consciously try to avoid left turns, but it would seem to make sense.

I would certainly advise visitors not to take their car when visiting a Dutch city center. Using public transportation is a lot easier (and cheaper).

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