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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

#4
post #3

Google maps, and other similar routing apps, should offer a no left turn option!

Heck, I'd be thrilled by a "avoid intersections where the bottom 20% of drivers get stuck waiting for several minutes trying to make the turn" option.

99% of the time I wouldn't use it. But the 1% of the time that I'm doing something stupid the last thing I need is a extraneous hard intersections.

It's not like Google doesn't have the location data to figure out the difference between intersections where traffic is slow and steady vs where people routinely get stuck.

Re: Remove left turns for less dangerous city traffic

#5
While I don't know of the safety impact of removing left turns, the actual trip time impact in a busy city is severely understated. In my city (700k people), an old European town, city center has seen the removal of a few key left turns in the past few years. Consequences for traffic outside city center: probably none. Consequences if you want to drive from within the city center to the outside (e.g. go back from a shopping mall / restaurant / business meeting): walk further (many places to park are inaccessible) back to the car, drive a block or two more than you normally would. Extra time: +5 minutes to walk, +10 minutes for those 1-2 blocks (traffic is heavy).

Now the "best" part: Consequences if you want to drive into the city center: you need to make a sequence of correct turns 1-2 kilometers before your target, and if you don't, you are punished with extra 20 minutes in traffic at least (and still won't land where you wanted) - there is simply no route to where you wanted to go unless you pick 1 specific ideal route which many drivers don't know. Results: if you know the city / have good gps (Google Maps sometimes gets it wrong) +10 minutes in traffic, if you don't - + 20-30 minutes in traffic.

[edit] You may ask "why you can't do a triple-right-turn?" that's because the city center is not a grid. Many streets are don't have cross-paths for long stretches around historical part of the city.

Now the really painful part... Your trip outside the city center is only 5-10 minutes. Losing an EXTRA 20 minutes is a huge loss, it makes the ttrip almost as bad as walking - but inside a car. Bad for everyone really.

My main beef is with the fact that many places in the city become almost inaccessible due to a huge reduction in possible routes. E.g. 7 years ago I could get to a large mall / parking area next to the town square maybe in 5-6 diffferent ways (allowing me to balance the traffic out).

Now there's 1 way only from my side of the city, and I can't balance anything out by going where others aren't.

Guess the "grid" street network is really a hard prerequisite.

As for safety, safety records in the city haven't moved at all in the past 10 years so I don't know. (But traffic has grown so maybe it's ok?)

Re: Remove left turns for less dangerous city traffic

#6
post #3

Google maps, and other similar routing apps, should offer a no left turn option!

And while we're at it, in the UK at least they should have an option for not sending you down bidirectional single track roads.

No, that 35 mile drive down twisty single track country lane with occasional passing spots will not save any time over the 40 mile motorway. Even if the road is _technically_ 60mph, you'll never reach that speed unless you're on a motorbike...

Re: Remove left turns for less dangerous city traffic

#7
post #5

While I don't know of the safety impact of removing left turns, the actual trip time impact in a busy city is severely understated. In my city (700k people), an old European town, city center has seen the removal of a few key left turns in the past few years. Consequences for traffic outside city center: probably none. Consequences if you want to drive from within the city center to the outside (e.g. go back from a s…

I am biased but why do we even need cars in the city center, or at the very least why should they be convenient? Could there not be a situation where you walk to the edges of the city center to pick up your car and leave from there? There are specific accessibility concerns that certainly need to be accounted for, but the idea that the average driver loses 20 minutes on a trip that should be 5-10 minutes doesn't seem like inherently an issue in this context.

edit-add: biased in the sense that I really dislike cars and live in NYC in large part because you do not need one here

Re: Remove left turns for less dangerous city traffic

#9
post #5

While I don't know of the safety impact of removing left turns, the actual trip time impact in a busy city is severely understated. In my city (700k people), an old European town, city center has seen the removal of a few key left turns in the past few years. Consequences for traffic outside city center: probably none. Consequences if you want to drive from within the city center to the outside (e.g. go back from a s…

>Extra time: +5 minutes to walk

why does removing left turns make it longer to walk? Can pedestrians even make "left" turns?

Re: Remove left turns for less dangerous city traffic

#10
post #9
post #5

While I don't know of the safety impact of removing left turns, the actual trip time impact in a busy city is severely understated. In my city (700k people), an old European town, city center has seen the removal of a few key left turns in the past few years. Consequences for traffic outside city center: probably none. Consequences if you want to drive from within the city center to the outside (e.g. go back from a s…

>Extra time: +5 minutes to walk why does removing left turns make it longer to walk? Can pedestrians even make "left" turns?

It's because they have to take a different longer route to a different parking space.
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