Timothy P. Reilly, P.E, Civil Engineer

A professor in college once told me that “every trip starts and ends with a pedestrian.” No matter what means of transportation people use along the way, they generally start their trip by walking out the door and end each trip by walking the last few steps to their destination. There are obvious exceptions to this rule, but his point was that pedestrian accommodations must be taken into consideration in any transportation network. Where this is especially true is within parking lots. In a typical commercial parking lot, each parking stall and each door into a building can be considered the starting point or ending point of a potential pedestrian trip. The larger the parking lot and the more businesses it serves, the more potential paths that pedestrians can be expected to take. Nearly all these potential pedestrian paths will conflict with one or more potential vehicle paths. With all these pedestrian-vehicle conflict points, the question becomes, “where should the property owner place crosswalks?”

When looking into whether drive aisles within a specific site are required to have crosswalks, it becomes clear that they are not often required by applicable regulations. Additionally, the Manual on Uniform Traffic Control Devices (MUTCD) warns against indiscriminate placement of painted crosswalk lines. Section 3B.18 of the 2009 MUTCD states: “Crosswalk lines should not be used indiscriminately. An engineering study should be performed before they are installed at locations away from a traffic control signal or an approach controlled by a STOP or YIELD sign.”

However, there is one circumstance where a design engineer will often choose to place a painted crosswalk within a parking lot: along an ADA-compliant walking path. Section 206.2 of the ADA standards explains that some of the places where accessible routes are required include between accessible parking spaces and the buildings they serve, from public streets and sidewalks, and connecting multiple buildings on the same site. Because ADA-compliant accessible routes require certain design features such as a cross slope less than 2%, the location of these accessible routes should be specified for pedestrians that require them when the surrounding area might require a steeper slope due to the grading of the site for stormwater management.

Timothy P. Reilly, P.E, Civil Engineer with DJS Associates, Inc., can be reached via email at experts@forensicDJS.com or via phone at 215-659-2010.