Should Warner Road bike lane have a “Combined” Turn Lane?

Disappearing Bike Lane; Warner Rd at Hardy Dr, Tempe, AZ

it is a common occurrence — familiar to every bicyclist — where you can be riding along a perfectly nice bike lane only to have it disappear for various reasons.

Bike lanes are highly prized for making cycling “more comfortable”; so I think it’s safe to say disappearing bike lanes would be considered quite stressful, and an impediment to cycling for many cyclists.

I have, over the past year, had occasion to regularly ride along Warner Road in Tempe (this area is sometimes referred to as “south” Tempe. Here’s a map of the general vicinity) between I-10 (the city limit) and McClintock Drive; it’s about 3.5 miles. The road is very much an arterial road with two fast through lanes (45mph, if i recall correctly) plus a bike lane each way plus some sort of middle lane throughout (it’s usually a TWLTL; two way left turn lane; it becomes a left turn lane at major intersections). The difficulty is at every intersection where there is a right turn only lane, the bike lane is dropped ~ 250′ from the intersection. This dropping occurs asymmetrically at some, but not all, of the major intersections. It is most prominent westbound: the lane drops at McClintock, Rural, Kyrene, Hardy, and Priest Drive. That is FIVE TIMES in three miles!

On the plus side; it mitigates the problem with bike lanes where through-cyclists being right hooked (by eliminating the bike lane altogether; drastic but effective). On the negative side, for through-cyclists… 1) it creates legal ambiguity between obeying the RTO traffic control device; and riding AFRAP (AZ has no enumerated exemption for RTO lanes) 2) it can be very difficult, if not harrowing, to merge into the right through lane with high-speed through traffic 3) riding in the RTO raises conflicts with oncoming left-turning traffic.

There is an alternative, sometimes called a “Combined bike/turn lane”; It doesn’t eliminate the negatives, but it does address some of them. E.g. it makes it explicitly legal to proceed straight through the (otherwise) RTO [see below info from Bruce Friedman for details]. From the FHWA page Bicycle Facilities and the Manual on Uniform Traffic Control Devices:

  • Allowable through the 2009 MUTCD… Shared-lane markings in exclusive turn lanes

  • Disallowed… Combined bicycle lane/turn lane where the lane attempts to establish a bike lane

[On older versions of that page, it used to allow for a BL combination experimentation which is now disallowed, and SLMs are ok] Here’s what it used to say:

Combined bike lane/turn lane:    Experimental if bike lane markings are used, but can be implemented at the present time if Shared Lane Markings are used instead of bike lane markings

Also discussed at NACTO and note that they show illustrations that are explicitly not permitted by showing a bike lane marking rather than a shared lane marking; And a paper evaluating similar scenarios is at

Would this be better? (I mean better than doing nothing?) I think so.

Just some examples

Los Alamos circa 2011

Here’s on from Los Alamos via labikes blogspot.  I need to check: is the right-arrow stencil a specified/standardized size?

Here (slide 9) is a pic of Miller Rd at Osborne, Scottsdale where they have installed a  sharrow into a formerly RTO lane.


Other troubles

Large lip between concrete drainage, and asphalt portion of bike lane (which shrinks to a very substandard ~ 2 feet) [this areas has since been “ground down”; i’m not sure that helps, here’s an updated pic of same area.
[ UPDATES: most of this info is superseded by an article dedicated to the issues at/near Warner and Kyrene. Also note this area was completely overlaid in late 2016 at which time the striping was changed dramatically. I left the original text here in strikethrough for posterity ]

There are a number of specific localized problems on this bike lane revolving around its intersection with Kyrene Rd; these can be seen on google maps. There are both maintenance issues, but also engineering ones. The problems seem to have their genesis in the fact that Warner road “shifts” at Kyrene; and the intersection is wider than normal, e.g. warner road is wider at kyrene than it is at Rural, or McClintock. The extra width has ironically taken away width from the bike lane (but why?); rendering it sub-standard for a relatively long stretch westbound; and has created “pinch points” of sub-standard width eastbound both east and west of the intersection.

The maintenance issue is the  road/asphalt portion being sloppy and way higher (perhaps as much as 2″) than the gutter. This problem is acute on Warner, eastbound, just east of Kyrene for a couple of hundred feet; where the asphalt portion of the bike lane shrinks to perhaps a mere two feet (bike lanes are supposed to have a minimum of four feet of usable width). See pic to the left, and also this one which is closer to the seven-11. [Update Aug 2014; the city DID address this by removing and replacing about 18″ width of asphalt next to the flat concrete gutter nearest the intersection; there is a bus pullout there. Unfortunately they tried to fix the portion further east, which is already problematic because it is substandard width, by “grinding” the asphalt down… Here is a current pic of the “pinch point” EB, east of Kyrene.

substandard-width designated bike lane in Tempe, AZ

The second problem is more insidious, and seems tied to places that want to be perceived as “bike friendly”… though this is shockingly poor design. For several hundred feet, westbound just west of Kyrene, there wasn’t enough room to make a bike lane along with all the other lanes, so what did they do? Made it anyways, of course… this causes all sorts of opportunities for horn blowing and side-swiping. (This is also the case at McClintock, northbound just north of Elliot Rd — which is actually worse, there it is narrower, and longer in this unacceptable condition). There is no particular reason there must be a bike lane stripe — if there’s not enough room to do it right, DON’T DO IT.

Tempe badly botched Rio Salado at 101; see pics here. Is it Tempe, or ADOT? You know what, I don’t care; I care that it is botched. This has it all, the ridiculously narrow “bike lane”; the huge disparity in height between the asphalt and gutter pan; the drainage grate in the “bike lane”. Is this a designated bike lane, or not? You know what? I don’t care — I care that it looks like a bike lane; because that’s what matters to bicyclists and motorists; it also happens to be contiguous with a designated bike lane, so for all intents and purposes, it is a bike lane.

Continuous Bike Lane?

Here is Dan Gutierrez’s diagram of converting from  dropped to continuous bike lane. So, the novelty here is that essentially he’s saying there techically is no RTO Lane, and traffic turning right merges into the BL in preparation for the turn. The bike lane is simply wider; in fact it’s as wide as the RTO would have been. The hitch is, as far as I can tell, that this is specific to CA because of the way they’ve explicitly written their manner of turning right statute which requires drivers to merge into the bike lane. The CA requirements are as far as I can tell very unusual; it’s not in AZ, nor is it in the UVC so don’t expect CA-style language anytime soon in other places.

12 thoughts on “Should Warner Road bike lane have a “Combined” Turn Lane?”

  1. This was the result of my Tempe 311 incident, it was closed but nothing was ever done. At first i got a phone call saying the field guys couldn’t locate; i replied with more specifics, yet the incident was simply closed…

    Request Id: 166095
    Case Access Code: 508453
    BIKE Lane has large height difference between asphalt and concrete. Creating a fall hazard. Also in same area, the asphalt portion of bike lane is sub standard in width.
    Closed On: 08/05/13

  2. The fundamental issue is that the arterials (1) are posted for high speed limits but (2) have many intersections. These two attributes work against each other. High speed limits facilitate traffic throughput, but a high frequency of intersections prevents that; a high frequency of intersections create a destination for traffic, but fast, noisy traffic make a place unattractive for walking, dining, and other land uses.

    Reducing speed limits approaching intersections would make merging less harrowing.

    It would be helpful to mark the merge zone by extending a dotted line from the end of the bike lane to the beginning of the turn lane.

  3. Here’s kind of what I’m talking about:

    Notice that turning cars first need to change lanes, across the bicycle lane, before they can make their turn. That implies checking for traffic, etc. whereas the Warner at Hardy photo implies that drivers can just head straight for the turn pocket without checking for bicyclists.

  4. I ride Warner often and notice the same things.

    I wish Tempe would do something more like page 10 (Eugene, Oregon),,
    rather than the page 9 example.

    I would agree with Derek, I wish Tempe would extend a dotted line from
    the end of the bike lane to the start of the turn lane.

    The biggest problem that I have with this stretch of Warner is the
    southern entrance to the ASU Research Park.
    There is a westbound car travel lane that transitions to a right turn
    ramp into the research park. The bike lane totally disappears.
    There is also a nonexistent bike lane on the west side of this
    intersection, where Research Park car traffic is allowed to
    merge onto Warner.
    Looking toward the intersection from the East:,-111.895028&spn=0.004722,0.005&t=h&z=18&layer=c&cbll=33.334947,-111.895156&panoid=9JjBXHCLqtNWjr9duq2ytg&cbp=12,274.11,,0,30.61

    I wish Tempe would spend some time to ensure that are bike markings do not disappear to intersections
    or where it is insufficient space to continue a marked bike lane.

  5. Hi Dave,
    Thanks for the comments.

    There is definitely much messy business around the ASU research park; I rarely ride on that section just because i live to the west.

    Regarding the proposed RTO treatment being, in effect Sharrows (what was done in Scottsdale at Miller and Osborne) vs. a dotted bike lane stripe continuing through the RTO lane (the example from Eugene, OR) — preferences notwithstanding, there’s a very good reason to NOT do the dotted bike lane treatment because that is “experimental” (requires a whole bunch of paperwork) whereas the sharrow-style is pre-approved…. “Combined bike lane/turn lane Experimental if bike lane markings are used, but can be implemented at the present time if Shared Lane Markings are used instead of bike lane markings”.

  6. I do not live in Tempe but frequently ride there, in particular in southern Tempe.
    1) all “fake” bike lanes should either be removed or made standard; e.g. Rio Salado between Priest and Hardy.
    2) Existing dedicated Bike Lanes should be fixed:
    a) McClintock north of Elliot (both directions) is severely sub-standard width for perhaps 500′
    b) Warner Rd at Kyrene has pinch points and other engineering problems. It is also sub-standard width westbound for several hundred feet
    c) Rio Saldo at 101 is a dangerous mess. Don’t blame adot — it’s in tempe!!
    3) I would *recommend* making existing bike lanes that are discontinuous due to right turn only lanes (examples i know of are Warner Road and Guadalupe rd) into “combined right turn lanes”; these now have interim approval from NHTSA see (this page)

  7. In August it was noted that a trendy new, experimental, green (the green is difficult to see in the pic) bicycle lane (in Minneapolis) was adjacent to a 5.5ft RTO lane (6.5 feet if you count the gutter), in an industrial location (railroad tracks on that block). The RTO arrow doesn’t even fit in the lane, it’s partially on the gutter.
    Supposedly it’s one of the “combined RTO+bike” lanes, as possibility which had never occurred to me, and which seems to be poorly implemented, since there’s a (dashed) longitudinal line and a bicycle symbol in it. “Combined” lanes are allowed (non-experimental) by the MUTCD, if an SLM is used, but BL markings are not allowed.

    Old/original page, link now dead
    “Experimental if bike lane markings are used, but can be implemented at the present time if Shared Lane Markings are used instead of bike lane markings”

    current page bicycle_pedestrian/guidance/design_guidance/mutcd/
    “Disallowed… Combined bicycle lane/turn lane where the lane attempts to establish a bike lane” and
    “Allowable through the 2009 MUTCD… Shared-lane markings in exclusive turn lanes”

    From: “”
    Sent: Tuesday, March 3, 2015 6:05 AM
    Subject: RE: combined RTO lanes

    There have been no changes to our thinking on the combined use of a lane for right turns by motor vehicles and straight-through movements by bicyclists. This is a lane that is being shared and shared-lane markings may be used. Carving out a bike lane from a right-turn lane that is not wide enough to accommodate both (the motor vehicle lane becomes very narrow in situations where this has been tried or proposed) is not acceptable.

    Some States have revised their rules of the road to allow bicyclists to proceed straight through an intersection from a right-turn lane. In those States that have not revised their laws, an EXCEPT BIKES supplemental plaque below the RIGHT LANE MUST TURN RIGHT sign or the Right Turn Only sign may be used to inform motorists, bicyclists, and law enforcement personnel of this exception.

    I hope that this information is helpful to you.

    Bruce E. Friedman, P.E.
    Transportation Specialist, MUTCD Team
    Office of Operations
    Federal Highway Administration
    1200 New Jersey Avenue SE
    Washington, DC 20590

  8. There’s a discussion of this treatment in the “Bicycle Facilities” chapter 14 of ITE Traffic Control Devices Handbook, 2nd Edition (“The Handbook augments the 2009 Edition of the Manual on Uniform Traffic Control Devices (MUTCD). The Traffic Control Devices Handbook, 2nd Edition provides guidance and information to implement the provisions of the MUTCD. The objective of the Handbook is to bridge the gap between the MUTCD requirements and field applications . . .
    See Figure 14-12.
    This chapter was written by Richard Moeur and John Ciccarelli.

    Also it turns out Gene H was involved back in 2007 w/the whole issue of “except bicycles” placard — there are a bunch of placards in the city of Phoenix at the time as noted here, that were in the process of being removed, and at more or less the same time, the City of Scottsdale was in the process of adding them.

    Mark A found this post from John Allen Right-turn lane as dual-destination lane?

    I completely agree that it is foolish and hazardous for cyclists to ride near the right side of a right-turn lane when headed straight across the intersection. That is the “coffin corner” situation that we lament when it kills a naive cyclist. But, on the other hand, I consider treating an empty right turn lane with a receiving lane or shoulder after the intersection as a dual-destination lane, and riding in its center or toward its left side, only to be a variation on the decades-old advice to choose lane position according to the rules of motion, and ignore the bike-lane stripe. I’m not alone in this, not at all. Installations formalizing this treatment have been made in a number of places in the USA.

  9. Gene H has a photo album of a whole bunch of “Right Lane must turn right / Except Bicycles” around downtown Phoenix.

    Many (all?) have since been reconfigured, eliminating the sign.
    E.g. 5th Ave SB at Roosevelt, the RTO lane was eliminated and replaced with a right buffered bike lane

    In a different configuration, a shoehorn BL was inserted at 5th Ave SB at I-10; the existing space of 3 lanes (2 thru and one RTO) was reallocated to squeeze in a ~ 4′ BL between the (now narrower) thru lane and RTO.

    Street view history shows the change happened between 2011 and 2014.

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