A variety of pavement markings are available to make bicycling safer. Generally the markings are for lane separation, for indicating an assigned path or correct position for the bicyclist, and for information about upcoming turning and crossing maneuvers. The Manual of Uniform Traffic Control Devices (MUTCD) is the national standard for all pavement markings (as well as signs and signals), and Part 9 focuses on "Traffic Controls for Bicycle Facilities."1 Some states may have their own supplement to the MUTCD.
Examples of pavement markings include the striping and identification associated with bike lanes, striping for paved shoulders, turning lanes at intersections, railroad crossings, and drainage grates or other pavement hazards or irregularities. A general guideline for improved bicycle safety is to make sure the markings are durable, visible, and non-skid. Markings are usually done with paint or thermoplastic. Paint is cheaper but tends to fade quickly, while thermoplastic lasts longer but may be slippery. If thermoplastic is used for bicycle markings, a thin, non-skid type is preferred. The State of Oregon has four different types of legend markings that can be used for bike lanes — hot poured thermoplastic, preformed thermoplastic, tape, and methyl methacrylate. Use varies by geography, weather, traffic volumes and pedestrian and bike counts. Amount of skid resistance varies with each product. Sometimes glass beads, crushed glass and aggregate can be added during placement to increase skid resistance, but the skid resistant particles tend to sink before the thermoplastic cools.
Care in the placement of painted markings will increase their longevity. For example, avoid placement of markings near far-side bus stops or near driveways or other locations, particularly those with high truck traffic, to avoid wear from tires.
More symbols are now being used to indicate the presence of bicycles in
the traffic stream, as well as the correct riding position in the traffic
lane. There are many international examples. In the United States, the
City of Denver, CO, introduced the "bike-in-house" marking for
shared lane situations many years ago. An experimental evaluation of a
modified version of this symbol, the "Shared Arrow," was performed
on a wide curb lane corridor in Gainesville, FL, in 1999.2 In
February 2004, the City of San Francisco completed an evaluation of a modified "bike-in-house" and "bike-and-chevron" markings
(see case
study #37). The Gainesville and San Francisco evaluations showed benefits
for the markings. The "bike and chevron" markings have come to
be known as the SHARROW, and this symbol has been approved by the California
Traffic Control Device Committee for use in California.
Other known U.S. cities with some variation of the markings described above include Chicago, IL; Cambridge, MA; Portland, OR; Warren and Waitsfield, VT; Seattle, WA; and Sacramento, CA. There continues to be movement toward adoption of some form of the arrow or chevron as a national standard, but as of this writing this is not complete.
A rough cost estimate of labor and materials for arrow and chevron markings applied using methyl methacrylate is $100 each. Costs of other markings would depend on type and materials used.