3 ms·

Making the lane more narrow does not have to equal putting two lanes of opposing traffic closer together. We can make the dividing line(s) wider to compensate.

Making the lane more narrow does not have to equal putting two lanes of opposing traffic closer together. We can make the dividing line(s) wider to compensate. To wit, this conversation revolves around residential neighborhoods, where cars frequently park on the street, where the speed limit is likely not 40MPH. Making the lanes narrow is meant to get people to follow the speed limits, I'd say at 30MPH or less.

AnthonyMouse 10y ago
> Making the lane more narrow does not have to equal putting two lanes of opposing traffic closer together. We can make the dividing line(s) wider to compensate. And now you're doing something different than the data and will plausibly get a different outcome. If the opposing traffic is not closer together then maybe people don't slow down as much or at all anymore. And you're pushing the cars closer to the pedestrians. > To wit, this conversation revolves around residential neighborhoods, where cars frequently park on the street, where the speed limit is likely not 40MPH. Yet that may nonetheless be the prevailing traffic speed, and the speed that emergency vehicles can reasonably travel when not impeded by "traffic calming" measures. That you didn't expect people to get the efficiency you're taking away from them doesn't mean you aren't taking it away. Moreover, fuel efficiency is a curve with an inflection point somewhere above 40MPH. That means 40 is better than 30, but it also means 35 is better than 25 and 30 is better than 20. > Making the lanes narrow is meant to get people to follow the speed limits, I'd say at 30MPH or less. Except that the speed limit is generally supposed to be set at the 85th percentile traffic speed (and is generally set ~10MPH below that for reasons of politics and revenue generation), so slowing down traffic will lead to a reduction in the speed limit.

AnthonyMouse 10y ago

> Making the lane more narrow does not have to equal putting two lanes of opposing traffic closer together. We can make the dividing line(s) wider to compensate. And now you're doing something different than the data and will plausibly get a different outcome. If the opposing traffic is not closer together then maybe people don't slow down as much or at all anymore. And you're pushing the cars closer to the pedestrians. > To wit, this conversation revolves around residential neighborhoods, where cars frequently park on the street, where the speed limit is likely not 40MPH. Yet that may nonetheless be the prevailing traffic speed, and the speed that emergency vehicles can reasonably travel when not impeded by "traffic calming" measures. That you didn't expect people to get the efficiency you're taking away from them doesn't mean you aren't taking it away. Moreover, fuel efficiency is a curve with an inflection point somewhere above 40MPH. That means 40 is better than 30, but it also means 35 is better than 25 and 30 is better than 20. > Making the lanes narrow is meant to get people to follow the speed limits, I'd say at 30MPH or less. Except that the speed limit is generally supposed to be set at the 85th percentile traffic speed (and is generally set ~10MPH below that for reasons of politics and revenue generation), so slowing down traffic will lead to a reduction in the speed limit.