Divvying in a suit and a skirt

Riding south, in the gutter pan, on Dearborn’s two-way cycle track.


There are many problems inherent to having a two-way cycle track (or protected bike lane) on a one-way street in a busy urban center. I’ll list them here to convince you that the next time the Chicago Department of Transportation proposes a two-way cycle track on a one-way street you should heavily question it (except in one circumstance I’ll outline in the discussion).

In two-way cycle tracks on one-way streets…

0. It’s less safe than one-way cycle tracks on one or both sides of a street. (See OECD passage below.)

1. It’s hard to pass same-direction cyclists. A cyclist who wishes to pass someone going in the same direction must watch for oncoming traffic, increasing the danger of passing if they miscalculated when they should go and reducing the opportunities to do so. It also presents a hazard for all cyclists, who have to watch out for oncoming cyclists who are passing a same-direction cyclist!

2. It’s unlikely there will be space to offer turn lanes. Busy cycle tracks need turn lanes, to separate cyclists who are going to slow and turn or stop before turning (in the case of pedestrians crossing), and those who are going straight. A turn lane could be accommodated if the cycle track can widen at intersections, but in practice it seems to be easier to split the cycle track into turn and through lanes.

3. It costs more. Opposite direction cyclists can’t use existing traffic signals and must have costly traffic signals with bike symbols (which also cost a lot to program). The need to have a yellow center line also means a two-way cycle track requires more paint.

Erik pointed out in the comments how this isn’t right. I mostly agree, but then I changed my mind on how important this is: The appropriate and best design for a bicycle facility shouldn’t have its quality compromised because of cost.

4. It interferes with decades of intuition gained from crossing one-way streets. Most pedestrians around the world are used to monitoring a single direction of traffic on a one-way street.

5. They’re anti-social. Two-way cycle tracks are narrower than one-way cycle tracks because the city street engineers likely have the same space to work whether they allow one- or two-way cycling. This means you can’t cycle and chat next to a friend.

6. They require that someone has to ride in the gutter. When two-way cycle tracks are built curbside on existing roadways, one direction of cyclists will always have to ride in the gutter, a slanted area of the road filled with water and debris. We could eliminate this by building raised cycle tracks with a new drainage system (either drain into the roadway, or into new grates).

7. There’s less room to avoid obstacles. If there’s a rock, pothole, or upraised manhole cover in your path, you go around it. But if there’s someone coming in the other direction you’ll just have to hit it and take the beating.

8. They don’t provide cyclists access to both sides of a street that has destinations on both sides. This is a conditional item, and moot if the options are a two-way cycle track on one-side or a one-way cycle track on one side. A cycle track on each side of a one-way street will provide bicycle access to destinations on both sides.

Keep reading for a deeper discussion on the situations where a two-way cycle track could be good.

Note: A two-way cycle track is scheduled to be installed on the left (east) side of southbound Clinton Street as part of CDOT and CTA’s Loop Link bus lanes project.

There may be a place for two-way cycle tracks

The Organization for Economic Cooperation and Development (OECD) published a review of international best practices for growing cycling and keeping cyclists safe (hat tip to Copenhagenize). The authors concluded (page 177):

  • “Bi-directional cycle tracks along roads invariably lead to non-conventional maneuvers at junctions and where such tracks terminate. These situations entail a significant risk of crashes. Two-directional cycle tracks along roads generally should be avoided, unless the advantages are very clear or the space constraints for two unidirectional cycle tracks insurmountable.” [Grand Avenue is under discussion right now and I would say that the street has a lot of excess space. It has a “pair” on Illinois Street, with similar excesses.]
  • Opposite direction cycling on streets where cyclists don’t need linear protection from motor vehicles (because of lower volumes or traffic speeds; like Chicago’s side streets) is a very different ballgame.

None of this is to say that having two single direction cycle tracks, on each side of a one-way street is bad. They’re better than having a two-way cycle track because cyclists would then have a bigger, direct network of good places to ride and reach destinations.

A two-way cycle track to access bike parking at a train station. It wouldn’t make sense here, in a car-free environment, to have a one-way cycle tracks on either side of something in the middle (there wouldn’t be a something in the middle). Photo: Jennifer Judge and Ben Russell

The Dutch have installed many (probably hundreds of) miles of two-way cycle tracks, but they are more akin to our two-way off-street multi-use trails as they’re only mildly aligned with streets, or they’re used in very particular situations – for example, to carry a busy segment of the cycle network on one side of a large road to a bridge on the other – and not in dense, tight, uniformly dimensioned urban street grids that dominate American cities and are rarer in Dutch cities.

Quite often the Dutch will build a two-way cycle track on each side of the street to accommodate their cycle route networks, avoid a busy junction or train station area, work in harmony with intersections that prioritize tram and bus traffic but that can still keep certain directions of cyclists moving without any delay, or to provide access to both sides of a busy retail area. Learn more about the geometry and engineering of two-way cycle track design on Peter Furth’s website.

Speaking of networks, two-way cycle tracks on one-way streets must be integrated into a bicycle route/path network differently. This isn’t to say it cannot be done, but it takes a different and more complicated approach because of the nature of the other streets that would have to be modified to “receive” bicyclists turning off of the two-way cycle track. It has so far not been implemented well in Chicago.

Furth’s website describes the advantages of a two-way cycle track as listed in the Dutch street design manual called CROW. They are convincing! Yet Dearborn Street in Chicago, the first urban two-way cycle track on a one-way street in a big American city, doesn’t fit those criteria. And neither does building two-way cycle tracks on other one-way streets in the central business district.

You wouldn’t have to reject the proposal for another two-way cycle track on a one-way street, though, if there was a single, thoughtful design plan – the evolution of a network proposal like Chicago’s Streets for Cycling Plan – for all of the streets and intersections involved attached with dedicated funds for the appropriate infrastructure redesigns. However, three years after the Dearborn cycle track was installed, it still doesn’t bicycle facilities connecting it to the Kinzie cycle track. There, a network plan and a design plan failed to materialize.

A local example of a complicated and deficient intersection design is that cyclists going northbound on Dearborn Street (a northbound, one-way street with a two-way cycle track) and want to turn east onto two-way Kinzie Street (which has no bicycle facilities) have no way to do so without putting themselves and others at risk or burden.

Here’s how I would make that turn: if the Dearborn light is green, come to a complete stop in the intersection and wait for the Dearborn light to turn red and the Kinzie light to turn green – ignore that I’m blocking northbound cycle traffic. If the Dearborn light is red, signal to cyclists behind you that you’re turning right, and then watch for Kinzie traffic, turn right, and merge into it. Neither situation is preferable.

It’s imperative to redesign intersections when adding cycle tracks, and two-way cycle tracks on one-way streets require a more intensive and complex design but add little to no benefit over having a single, one-way cycle track, or one-way cycle tracks on either side of the street.

This slide from an APBP webinar briefly lists why a two-way cycle track may be better than a one-way cycle track.

This slide from an APBP webinar briefly lists why a two-way cycle track may be better than a one-way cycle track.

P.S. I laughed when I saw these three reasons [PDF] supporting a two-way cycle track over a one-way cycle track, because all of them are the same labels I’ve used to denote the disadvantages of using a two-way cycle track.

  1. Space limitations. Advantage: You don’t have enough room to put in two, appropriate-sized one-way cycle tracks, so you build a two-way cycle track. Disadvantage: Each cyclist now has personal space limitations.
  2. Wrong-way bicyclists. Advantage: You provide a space for people who choose to cycle the wrong way. Disadvantage: A two-way cycle track is less an accommodation for this rider, and more an admission that your cycle network doesn’t accommodate the rider.
  3. Difficult street crossings. Advantage: I don’t think there are any! Disadvantage: Start reading from the top of this post.