Colored bicycle lanes and intersection treatments: International overview and best practices

The use of colored pavements for bicycle facilities represents an interesting strategy for supporting the implementation of a high-quality cycling network. The distinctive coloration of dedicated lanes, tracks or shared paths provides a clearly delineated route, making the infrastructure more attractive as well as legible and intuitive, especially through intersections and junctions. The additional emphasis resulting from the coloring enhances a change in the road users' behavior, but its safety effectiveness seems to be particularly related to several site-specific contextual features. Although some of these benefits are well established and multiple applications of colored pavements are widespread around the world, most of cycling design standards and guides, which are usually written only in the language of the country that drafted them and are often difficult to find, completely lack in technical recommendations and concepts regarding the use of color for cycling provisions. Thus, based on an extensive worldwide literature search from more than 80 official design guidelines, manuals and standards and 50 scientific articles, the authors have structured a guided overview of the state of the art/practice concerning the use of color for bike facilities at the international level, including the latest innovative and experimental schemes. The review is not intended to be a summary of manuals, but is conceived as a decision-makers' and designers' tool for a rational planning, construction, maintenance and management of colored cycling infrastructures, able to favor a cultural and technical interchange. After a first section in which the main locations where to use colored surfaces were highlighted (corridor or spot treatments), the commonly used colors (red, green and blue) have been identified, explaining the hierarchical and/or combined reasons (regulatory and legal limitations, visual-perceptual aspects and application/maintenance requirements) behind this choice. Finally, the different coloring techniques associated with the pavement materials have been described.