Re: the Austin article

You also need to consider the width of the streets.

The typical suburban standard requires 12 foot traffic lanes and 10 foot parking lanes (44 foot street width).

New Urbanists, who design a connected street grid, have generally gone back to the traditional street width, 10 foot traffic lanes and 8 foot parking lanes (36 foot street width).

In some cases, New Urbanists have gone even further. Andres Duany has designed neighborhood streets as narrow as 19 feet. He calls them “yield streets,” because if two cars are going in opposite directions they cannot pass each other and one must yield by pulling into the parking lane.

Narrower streets are needed to slow down traffic when you have a connected street system that lets traffic drive through neighborhoods. You can imagine that “yield streets” slow traffic considerably. If this subdivision were built with a connected grid of yield streets, it would require less asphalt than it does with its current cul-de-sacs.

Developers build those wide streets, because they are generally required by law.