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AASHTO Guide for the Development of Bicycle Facilities
Posted on March 23rd, 2010 12 commentsI have trouble laying my hands on this sometimes, so here is a source for the AASHTO Guide for the Development of Bicycle Facilities,1999 — which is the most recent final version; it’s a largish (2.5MByte) .pdf available from the here, via azmag.gov (Maricopa Assoc of Governments). You can purchase the book directly from AASHTO
This book gives the accepted guidelines for dimensions and usage of various bicycle facilities, i.e. bike lanes, wide curb lanes.
There is also a DRAFT revision dated February 2010: DRAFT AASHTO Guide for the Planning, Design, and Operation of Bicycle Facilities.
Bike Lane / Bicycle Lane Dimensions
I frequently have to look this up, so here are the design specification dimensions for bike lane per the 1999 Guide (p.22, 23)
For roadways with no curb and gutter, the minimum width of a bike lane should be 1.2 m (4 feet). If parking is permitted, as in Figure 6(1), the bike lane should be placed between the parking area and the travel lane and have a minimum width of 1.5 m (5 feet). Where parking is permitted but a parking stripe or stalls are not utilized, the shared area should be a minimum of 3.3 m (11 feet) without a curb face and 3.6 m (12 feet) adjacent to a curb face as shown in Figure 6(2). If the parking volume is substantial or turnover is high, an additional 0.3 to 0.6 m (1 to 2 feet) of width is desirable.
The recommended width of a bike lane is 1.5m(5 feet) from the face of a curb or guardrail to the bike lane stripe. This 1.5-m (5-foot) width shouldbe sufficient in cases where a 0.3-0.6 m (1-2 foot) wide concrete gutterpan exists, given that a minimum of 0.9 m (3 feet) of ridable surface is provided, and the longitudinal joint between the gutter pan and pavement surface is smooth.
So in summary, recommended width:
- If no curb and gutter / no parking : 4 feet
- If curb and gutter / no parking: 5 feet from curbface, with a minimum of 3 feet of “ridable surface”, i.e. up to two of the 5 can be gutter pan.
- If parking: generally 5 feet, see document.
By the way, there is a handy extract of the Guide including cross sections diagrams within lesson #15 of FHWA-HRT-05-133 Federal Highway Administration University Course on Bicycle and Pedestrian Transportation. The material is available in both pdf and ppt; and has a whole spectrum of information pertaining to planning bike and ped facilities.
Wide Curb Lane Dimensions
From page 17 of the 1999 Guide (emphasis added):
In general, 4.2 m (14 feet) of usable lane width is the recommended width for shared use in a wide curb lane. Usable width normally would be from edge stripe to lane stripe or from the longitudinal joint of the gutterpan to lane stripe (the gutter pan should not be included as usable width).
It then goes on to list several cases where 15′ is indicated, though it discourages wider than that on the theory that cars might then “double up” in the one lane.
The 2010 DRAFT Guide
The 2010 draft guide, link above, has a LOT of extra detail and generally stronger wording, e.g. the 1999 Guide refers to “the recommended width of a bike lane is 1.5m(5 feet)” whereas the 2010 Draft says “the minimum bike lane width is 5 feet…” (empahsis added).
The Draft Guide also, by the way, specifies that the measurement is made “to the center of the bike lane line”. The 1999 Guide doesn’t specify.

R3-17 Sign
Bike Lane Signs & Markings (MUTCD)
This is from the MUTCD but I lumped it in here because I thought it was interesting: as of the current MUTCD (Dec 2009, as of this writing), the R3-17 signs are not mandatory, section 9B.04: “If used, Bike Lane signs and plaques should be used in advance of the upstream end of the bicycle lane…”. It used to say “Bicycle Lane signs shall be used in advance…”
This is surprising to some, including me. The thinking is, apparently, that the ground markings are the important piece. Here is a nice presentation-style document outlining all bike+ped oriented changes in the 2009 MUTCD, bikes are part 9.
For more explanation, see bicycle (part 9) related FAQs.
The term markings refers to the various paint on the ground that may or must be used to mark a bike lane. The stripe is unambiguously and absolutely required – “Longitudinal pavement markings shall be used to define bicycle lanes” (my emphasis added) see 9C.o4 Markings for Bike Lanes, and note that no particular stripe width is specified. However, the painted words or symbols/logos, and arrows are “if used”, which would suggest they are optional. Not so fast! According to the above-mentioned faq, due to Item C in Paragraph 6 of Section 3D.01 the word, symbol, and/or arrow pavement markings are required. Apparently this apparent confusion has already been recognized by the NCUTCD’s BTC (that is, the National Committee on Uniform Traffic control Devices, Bicycle Technical Committee: ncutcdbtc.org) and a fix is in the works. The proposed fix clarifies in 9C.04 that markings are required, by adding them to the standard (thanks to Richard Moeur for pointing this out). The official status of the request 9(9)-26 – one imagines this can take a long, long, long time if it is granted; and in the meantime it’s not clear what the status of all this is?? Hopefully, it will one day show up as an ‘interim approval‘.A “Longitudinal pavement marking” is defined in 3A.06 : noting that width for “Normal line—4 to 6 inches wide”; I’m sure the color is specified as white somewhere else?
How wide is the bike symbol marking? I just noticed that figure 9C-6 in the 2003 edition has the grid lines for the markings; the symbol is 4 feet minus 8″ wide. The word markings are significantly narrower, 4′ minus 16″. I’ve always wondered about that.
Note that the MUTCD has in some sense the force of law in Arizona, see The MUTCD and A.R.S.
7 responses to “AASHTO Guide for the Development of Bicycle Facilities”

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Thank you so much for putting the guidelines on the web. Beats $99 for hard copy AND I was able to quickly resolve the details of an assertion made in a bike/ped workshop for planners and TEs.
Actually thanks go to MAG for posting it, but I know exactly what you mean!
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On page 5 of the 1999 Guide it says,
“As Figure 1 shows, bicyclists require at least 1.0 m (40 inches) of essen- tial operating space based solely on their profile. An operating space of 1.2 m (4 feet) is assumed as the minimum width for any facility designed for exclusive or preferential use by bicyclists. Where motor vehicle traf- fic volumes, motor vehicle or bicyclist speed, and the mix of truck and bus traffic increase, a more comfortable operating space of 1.5 m (5 feet) or more is desirable.”
So the “3 feet of ridable (sic) surface” is not compliant with the 4 feet minimum operating space.
Why should bicyclist space be reduced to 3′ of usable surface just because the seam of the unusable gutter pan is smooth!
As an aside, I recently wrote a 1 page paper describing what the dimensions in Figure 1 mean.
http://bicyclingmatters.wordpress.com/infrastructure/design-bicyclist-width/
5 Trackbacks / Pingbacks
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[...] other articles on critical width; see AASHTO for dimensional guidelines for (real) bike [...]
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[...] an engineering perspective, the authoritative AAHSTO Guide for the Development of Bicycle Facilities, 1999 says minimum 14′ usable width for [...]
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[...] In the common arterial around here: no-parking, narrow-multi-laned arterials (usually 11′ lanes) — it seems to me that 6′ from the curbface to centerline of the marking is about right (has anyone done the math?) is appropriate. Narrow meaning not wide enough to safely share side-by-side with a vehicle — generally recognized as anything 14′ or below (see e.g. AASHTO). [...]
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[...] safety drawbacks which usually go unmentioned. here is a more balanced view, as presented in the Feb 2010 (the latest) Draft AASHTO Guide, p.78 (my [...]
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[...] More about designated Bike Lanes. [...]
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Marjorie Holderer June 23rd, 2010 at 09:33