Lane Width

[bwana39]

Some years ago, Texas had many 14' lanes. They have swapped those for 12' lanes and wider shoulders. Of course several freeways in texas have been "temporarily" restriped to 11'. People on here hate this.

The article I am going to post suggests 12' lanes CAUSE traffic problems.

https://www.bloomberg.com/news/articles/2014-10-06/why-12-foot-traffic-lanes-are-disastrous-for-safety-and-must-be-replaced-now

What do you think ideal lane width is / should be?  It may vary, based on the type of road and location, but....Looking for opinions.

[Brandon]

The article seems to be written by someone who has no idea how to design for trucks.  Most trucks are 8 feet wide (2.45m).  12 feet gives them a 2-foot margin of error on each side.  10 feet only leaves a one-foot margin of error.  12 feet is fine for freeways, divided highways, arterials, and any other road/street being used as a truck route.  10 feet is fine for minor streets not expected to see truck traffic.

[kalvado]

The older I get the more I appreciate the old saying "If you are not a liberal at 20, you have no heart. If you are not a conservative at 45 you have no brain". Urbanists (and environmentalists, as well as many progressives) are nice  and well-minded people who just need to grow up.     
Street width is not set for nice car movements or bike-pedestrian interactions. It is set wide enough to allow fire truck operations. Wider streets are required for operations in higher buildings.

There are no words "fire" or "truck" in linked article.  So much for tabloids.

[Big John]

12 foot is optimal,  12 inches is too narrow.

[J N Winkler]

The article was published on October 6, 2014, and I think it is safe to say any influence it has had on urban arterial design in the succeeding nine years has been minimal.  It is definitely written from a New Urbanist perspective.

I consider some of its arguments suspect.  For example, it says the capacity of 10-foot lanes is about the same as that of 12-foot lanes.  That might be true for measured capacities in urban settings where other constraints typically apply, but the rule of thumb since the 1950's has been that the capacity ceiling for a 10-foot lane is about 70% that of a 12-foot lane.

[Max Rockatansky]

Some of the most enjoyable roads around me are the relic 7.5 foot lane Portland Cement relics of early state highways.  They certainly do a good job at making sure you pay attention to not wandering given the margin for error is slim.

[hotdogPi]

Number of lanes, as well as presence of a median, matters a lot more than lane width. Most roads in Massachusetts are a single lane in each direction. I assume this is the case in most of New England, and I've been told Michigan does it, too. Most other places have multilane roads as the norm. I can cross most streets easily as a pedestrian where I am, and I definitely have to be more careful with the few multilane ones that exist.

[SkyPesos]

Freeways: 12'
Arterials: 10-11'
Urban streets: 10'

[kphoger]

[jeffandnicole]

Per the article: "Granted, this study covers only one type of road, but there is no reason to expect opposite results on, for example, straight urban roads."

Um, yes, studies are always done (or should be done) on other types of roads.

BTW, here's the author's website: https://www.jeffspeck.com/

The article seems to be written by someone who has no idea how to design for trucks.  Most trucks are 8 feet wide (2.45m).  12 feet gives them a 2-foot margin of error on each side.  10 feet only leaves a one-foot margin of error.  12 feet is fine for freeways, divided highways, arterials, and any other road/street being used as a truck route.  10 feet is fine for minor streets not expected to see truck traffic.

And that's just the truck.  That doesn't account for its side-view mirrors.

[1995hoo]

I remember the 10-foot lanes, with a wall on either side and no shoulders, on the old Goethals Bridge. That was just plain nerve-wracking to drive over, especially if there was a large truck around.

[kphoger]

I remember the 10-foot lanes, with a wall on either side and no shoulders, on the old Goethals Bridge. That was just plain nerve-wracking to drive over, especially if there was a large truck around.

My first day of training to drive a box truck, I drove over the Cairo Mississippi River Bridge.  Ten-foot lanes with heavy truck traffic, and road construction.  18-wheeler's tires rode the center yellow stripe, because there were orange cones along the edge line.  A white-knuckle drive for me, let me tell you!

[CtrlAltDel]

The older I get the more I appreciate the old saying "If you are not a liberal at 20, you have no heart. If you are not a conservative at 45 you have no brain". Urbanists (and environmentalists, as well as many progressives) are nice  and well-minded people who just need to grow up.     
Street width is not set for nice car movements or bike-pedestrian interactions. It is set wide enough to allow fire truck operations. Wider streets are required for operations in higher buildings.

There are no words "fire" or "truck" in linked article.  So much for tabloids.

The number of people on this forum who have indirectly called me an idiot increases.

[kalvado]

The older I get the more I appreciate the old saying "If you are not a liberal at 20, you have no heart. If you are not a conservative at 45 you have no brain". Urbanists (and environmentalists, as well as many progressives) are nice  and well-minded people who just need to grow up.     
Street width is not set for nice car movements or bike-pedestrian interactions. It is set wide enough to allow fire truck operations. Wider streets are required for operations in higher buildings.

There are no words "fire" or "truck" in linked article.  So much for tabloids.

The number of people on this forum who have indirectly called me an idiot increases.

You're always welcome.

[CtrlAltDel]

The older I get the more I appreciate the old saying "If you are not a liberal at 20, you have no heart. If you are not a conservative at 45 you have no brain". Urbanists (and environmentalists, as well as many progressives) are nice  and well-minded people who just need to grow up.     
Street width is not set for nice car movements or bike-pedestrian interactions. It is set wide enough to allow fire truck operations. Wider streets are required for operations in higher buildings.

There are no words "fire" or "truck" in linked article.  So much for tabloids.

The number of people on this forum who have indirectly called me an idiot increases.

You're always welcome.

Oh, how kind.