Shared Lane Markings . . . Sharrows

Shared Lane Marking in the 2200 Block of Washington Street East. Submitted photo.


You see these things in certain areas around Charleston (notably downtown and the East End) and you say, just what are these things?

They are Shared Lane Markings (SLM).

What are Shared Lane Markings, commonly referred to as “sharrows”?

Begun in Denver, Colorado, in the 1990s and the “sharrows” term coined a few years later in San Francisco, sharrows have very good intentions but leave people more confused than helped.

Officially, they have been adopted into the Federal Highway Administration’s (FHWA) Manual on Uniform Traffic Control Devices since 2009.

First, what a shared lane marking is not. It is not a bike lane. They are intended to be used on streets where posted speeds are less than 35 miles per hour.

Intentions and benefits of sharrows:

  • Guide bicyclists away from parked cars to avoid “doorings.”
  • Convey information regarding bike routes, avoid wrong-way riding, and find gaps in bike lanes (of which Charleston has none currently).
  • Alert drivers to the presence of bicyclists.
  • No additional street space used.

Sharrows are not a substitute for cycle tracks, bike lanes, or other types of separated bike infrastructure. They are a complement to a comprehensive bike network. They should be used in low -density, low-speed traffic situations and to fill gaps within the bike network, transitionary segments, and so on.

So, what does it all mean?

If you’re driving a car, be on the look out for bicyclists (which should be the case on all streets, of course). You know they’re going to be there. They can legally have the lane. Be courteous and allow space.

If you’re on a bicycle, use the lane. Be aware of your surroundings, as in all cases, but the sharrow can assist you in your routing. To repeat, they are not a substitute for bike lanes but they can be of use within the overall bike network.

You’ll most notice them around Downtown and the East End. The West Side has been left out of all cycling infrastructure so far (an exception is the Kanawha Boulevard shared use trail but that does not serve the heart of the community), but we will make sure that is addressed in the future as we work with our civic leaders to build and improve our bike network.

The current shared lane markings are notably marked along Charleston Bike Routes C-1, E-1, and E-2. You can preview those routes on our custom Google Map along with bike parking options and more.