I just came across the NACTO publication Designing for Small Things With Wheels, released February 2023. I’m still digesting the publication, which is available online for download. Already it has been eye-opening for me, a person who used to keep up with bikeway designs, but hasn’t paid much attention recently.
The working paper’s basic premise is that bikeways must be designed for the modern complement of devices, with widely varying widths, and also that bikeways must be designed so that people can safely and easily pass each other. Bike lanes have gradually evolved from 4 feet to 5 feet to 6 feet, but at least in Sacramento and the region, have not gone beyond that. But the working paper indicates that we need to start with 8 feet, to accommodate cargo bikes which are becoming much more common in the region, and go up from there. A chart from the working paper is below (page 11).
Given that I believe that motor vehicle design speeds over 30 mph require separate bikeways to keep riders of all ages and abilities safe, this means future separated bikeways should be a minimum of 8 feet. However, bikeways this wide encourage motor vehicle drivers to use them for travel, and to park in them, ‘for just a moment’ or longer. My take is that this means we must create bikeways that are at the sidewalk level, or if street level, that are completely protected by hard infrastructure such as curbs. Paint and vertical delineators (soft hit posts) will not do it. So, I need to throw out all the previous designs that I’ve suggested for streets with protected bikeways. I also need to give serious consideration to sidewalk-level bikeways that place a curb between any motor vehicle use and users of small wheels. Where does that leave parking protected bikeways that use parked cars as the buffer, at least when the parked cars are there? I’m not sure. Like I said, this is eye-opening and I’ll need to do a lot more thinking and research.
What I still do think is that bike facilities necessary depend on street design speeds (which are not currently but should be the same as posted speeds)
- 20 mph or less – no bicycle facilities needed
- 21 to 30 mph – standard bike lanes (Class 2 in California)
- above 30 mph – separated bikeways (Class 4 in California)
Yes, this does affect what I was thinking about writing for bicycle facilities in my series on the City of Sacramento update of Street Design Standards.
3 thoughts on “bike lane widths”
[…] raised by the need for wider bikeways to accommodate wider devices and passing, the topic of my bike lane widths post, I am starting to think more and more about sidewalk-level bikeways, where the bikeway is at […]
[…] Part of an ongoing series of posts to support better streets in the City of Sacramento during their 2023 update of Street Design Standards. New standards must be innovative, safe, and equitable, and it will take strong citizen involvement and advocacy to make them so. See also separated bikeways and bus routes, sidewalk-level bikeways, and bike lane widths. […]
[…] cars are not present. For information on why a seven foot bikeway is not sufficient, please see bike lane widths. NACTO recommends at least eight […]