Janet Barlow, COMS
Certified Orientation and Mobility Specialist
Accessible Design for the Blind
Billie Louise (Beezy) Bentzen, COMS
Certified Orientation and Mobility Specialist
Accessible Design for the Blind
Coordinator of Research (Retired)
U.S. Access Board
Identifying the Sidewalk/Street Boundary
Recognizing that you’ve arrived at the street involves assessing a number of cues:
· The end of a building line transitioning to the openness of an intersection;
· Changes in wind direction;
· The sound of idling or moving perpendicular traffic, or turning and/or stopping parallel traffic;
· A down-curb, curb ramp, or similar sloped transition in the sidewalk;
· Detectable warning (DW) surface underfoot at the flush connection to the street.
· The locator tone of an accessible pedestrian signal (APS), where one is installed;
· The presence of waiting pedestrians, or the whistle of a traffic officer or bell of a turning cyclist.
If you feel the counterslope of a downslope to the gutter followed by an upslope, you may have inadvertently stepped into the street at a location without other cues.
If you are expecting to find the street edge and do not, you may also be in a location where the sidewalk has been extended at the corner, called a bulb-out or curb extension, which shortens the crossing distance and improves pedestrian visibility, but means that the crossing begins further from the building line than usual.
Curb ramp slopes may be relatively steep, which can help in detecting the street edge. And the ‘toe’ or base of a curb ramp must fall within the crosswalk area; however there is no requirement that the curb ramp slope be aligned with the direction of travel on the crosswalk. There are many different ways that curb ramps can be built to connect the sidewalk to the street at a crossing. Understanding those possibilities may help you recognize the edge of the street better as you travel.
The most common connection is a perpendicular curb ramp, in which a section of the sidewalk slopes down to the street. The edges of the ramp may be ‘returned’ with curbs on each side of the ramps or ‘flared’ with sides that slope back up to the sidewalk level. Returned curb edges on the ramps are usually found where there is a landscape strip between the curb and sidewalk, and flared sides are usual when the sidewalk is paved to the curb. Perpendicular ramps need wide sidewalks to be usable – almost 12 feet where curbs are 6 inches in height.
In older sidewalks, there may be only one curb ramp, at the apex of the corner; these are often called ‘diagonal’ ramps because they are oriented towards the center of the intersection rather than towards the crosswalk. Newer sidewalks should have one ramp for each crosswalk but the slope of those ramps may not be aligned with the crosswalk because the base of the ramp must be square to the gutter to avoid causing tipping problems for wheelchair users.
DWs should be located across the base of the ramp, just behind the edge of the street. DWs are required to line up with the edge of the street and the slope of the ramp; they may not be aligned with the direction of the crosswalk.
In narrower sidewalks, parallel ramps are common; this is a ramp type in which the whole sidewalk slopes down to a level landing and then back up again. Parallel ramps are usually installed in narrow sidewalks that are along the street edge, often called curb-attached sidewalks, or sidewalks at back of curb. There are flat areas at street level where you may have to turn to cross within the crosswalk. Parallel ramps may be ‘diagonal’ or have a shared landing, with only one location to cross from at the corner, or there may be two landing areas, one for each crossing. In that case you’ll find the sidewalk sloping up and down twice as you turn a corner. One of the more confusing aspects of parallel ramps is that there may be a curb at the back of the landing, to keep dirt or landscaping from washing down into the landing space, so you might find yourself walking down a sloping sidewalk to an area that is located between a DW and a low curb. In most cases, you are still on the sidewalk, but it can be confusing to find a curb on the side of the sidewalk away from the street and DWs on the other. DWs should be installed along the edge of the street at the landing, for the full width of the edge that is flush with the street.
In some cities, a combination of these two curb ramp types is used. First, the sidewalk slopes down a bit, connecting to a level landing from which a pair of short perpendicular ramps connects to the street.
Some cities use lower-slope ‘blended transitions’ in which the whole corner slopes gently down to the intersection. In these connections, the DW will extend in a quarter-round curve from one crosswalk to the other, giving few directional cues to the crossing.
Similar low-slope connections will be found where the crosswalk itself is raised to sidewalk height – a raised crossing, sometimes also described as a speed table for its traffic-calming effects. Raised crossings can provide accessibility in very narrow sidewalks where there is little room for curb ramps. Because there is no slope or gutter to identify them, DWs will be the only indication of the boundary between sidewalk and street. This is also true at medians and pedestrian islands that are cut through level with the roadway surface.
The underfoot cues provided by curb ramps -- slope, DWs, gutter counterslope -- can augment cues about street location obtained from traffic sounds. But curb ramps and blended transitions are not accurate indicators of crossing direction and should not be relied on as an indication of the direction of the crossing.
Travel strategies for approaching an intersection and detecting the street edge include:
· Assessment of audible traffic and other cues;
· Attention to changes in building line, intersecting sidewalks, locations of poles and “street furniture”
· Constant contact technique to detect small changes, slowing to maintain your line of approach;
· Attention to small changes in slope or texture;
· Cane contact to the side to locate a curb when you think you’ve reached the street edge on a curb ramp
· Pushbutton locator tones of audible signals;
To help detect the street/sidewalk boundary, request the installation of DWs or other features. The pushbutton locator tone of an audible pedestrian signal can also indicate that you’re close to the street and crossing so requesting audible and vibrotactile pedestrian signals can add wayfinding information.
Locating the crosswalk
Traditional strategies for locating the crosswalk assume that the sidewalk, curb ramp or other transition, and the crosswalk itself are all in-line with your approach heading so you can maintain your line of approach when you come to a curb or corner. However, sidewalks and streets and their intersections are rarely so standardized these days. Remember that the curb ramp is supposed to be within the crosswalk; the location of the ramp may provide a good cue about the crosswalk location. If you reach the street from the ramp or blended transition area, DWs will indicate the sidewalk/street edge, but the DWs may not be lined up with the crossing direction and may not indicate a good crossing location.
The crosswalk may not be at the corner, but could be offset. Streets may curve or expand to add vehicle lanes or have very rounded corners to allow trucks to turn, or cars to turn at higher speed. In some locations, one leg of the crossing of the major street may be closed to pedestrians without any accessible information (like a fence or other barrier).Streets that don’t meet at right angles will have angled crossings, and some streets are engineered with separated right turn lanes or roundabouts.
Strategies to locate crossing points and refine crossing direction rely on an evaluation of the corner location and traffic movement in all directions. This takes time.
· Listen to parallel traffic as you approach a corner. Do you find that the parallel traffic seems to be moving behind you, or are you no longer sure which is your parallel traffic? Suspect a large-radius corner, a channelized turn lane you will cross to an island for the major crossings, or a roundabout. Listen more carefully for cues that indicate what the intersection geometry may be. Be aware of your body turning or your cane dropping off the curb to the side (you may think you’re veering toward the street, but it may be that the street is curving around the corner). Stop and listen for traffic on both streets. Possibly ask another pedestrian or a friend about the geometry.
· Trail the outside shoreline or curb (be careful of turning traffic) and use a wide cane technique to find the curb ramp. Analyze the relationship of the curb ramps. Listen carefully for parallel and perpendicular traffic to decide whether the curb ramp is more or less perpendicular with the street you want to cross, or is an apex (single diagonal) ramp directed toward the center of the intersection.
· Position yourself on the side of the curb ramp away from the center of the intersection; this will usually be within the crosswalk area and puts you close to parallel traffic but not too close. Many feel that it is often the best place to begin crossing from.
· Expect to find crosswalks (and curb ramps) at channelized turn lanes about halfway between the parallel and perpendicular streets.
· At roundabouts, the crosswalk for the parallel street will be before you reach the corner and the crosswalk for crossing the perpendicular street will be after you’ve completely rounded the corner. You have to turn toward the street to cross.
· Be aware that the presence of DWs does not mean that there is a safe crossing at that location.
· Once you have located the crosswalk, explore to find landmarks that work well for you, that you can find reliably, and that you may be able to use for alignment.
When intersections are newly constructed or reconstructed, they should incorporate useful environmental cues such as continuous landscaping between roadway curb and sidewalk, making curb ramp locations more obvious, barriers/fences/bollards to help define the travel path, and short curb radii to permit directional curb ramps where these are feasible. However, it’s quite common to see newly build intersections without such features.
Where effective cues to crossing location aren’t available at existing intersections, request an APS with a locator tone and tactile arrow to indicate crossing location or planters or landscape strips located to frame the sidewalk and crosswalk.
Aligning to Cross
Traditional strategies for aligning to cross assumed that the crosswalk was relatively well-aligned with the direction of travel on the sidewalk and included:
1. Maintain line of approach
2. Align with parallel traffic (traffic moving alongside you in the same direction as your desired crossing)
3. Square off with perpendicular traffic (traffic that you are intending to cross) and/or curb
With the non-traditional curb ramp and sidewalk designs being used now, it may be very difficult to maintain a straight line of approach. And with the need to push a pedestrian pushbutton to have adequate time to cross the street, it is not usually possible to hold the approach line and cross because of the need to find and use the pushbutton before crossing. In many instances, there is little or no parallel traffic, such as when you are crossing a major street with little regular traffic on the minor street, the ‘top’ of a T-intersection, or an offset intersection. Careful analysis and additional time may be needed to analyze crossing direction where parallel streams of traffic don’t provide good cues. Some intersections have angled and/or multiple legs and there is no standard for crosswalk orientation. At those kinds of locations, some crosswalks may be perpendicular to the street (and thus the shortest crossing), while others will take the angle of the intersection (requiring longer travel in the street, but possibly more parallel to traffic). Finding the curb ramp(s) , one can identify the departure point, but the route to the arrival curb may be unclear if there is not a pedestrian signal with a locator tone to act as a beacon or some other wayfinding modifications.
Parallel/perpendicular sound cues will not be available at channelized turn lanes (slip lanes) that diverge from one street direction to connect to the intersecting street. Crossing this lane connects to a pedestrian refuge island where the major streets can be crossed using standard techniques. These channelized turn lanes will typically have one crosswalk at the apex (or center) of the curve, however, that is not standardized at this time; crosswalks to the island may be marked along either street instead. The curb ramp may provide useful cues to crossing direction, and crossing perpendicular to traffic movement can be a good strategy if you know the crosswalk is at the center of the curve. The same technique may work in circular intersections -- roundabouts and large rotaries, but the crosswalks may be angled in ways that make it very difficult to determine appropriate alignment. Landscaping, curb ramp direction and other cues may be helpful, but traffic sound cues will not usually provide good alignment cues.
Strategies for determining travel direction should not rely on curb ramp slope or DW orientation, as these may be designed for wheelchair travel. Work is underway nationally to promote more directional curb ramps, but existing ramps may not be replaced for many years. As mentioned earlier, the curb ramp/DW can identify a starting point, since the base of the ramp must be within the crosswalk if it is marked.
All these changes require some changes in how you align for a crossing. To align at an unfamiliar crossing, approach the intersection, holding your line of approach line as well as you can, and stop at the curb or edge of the street. Listen to the traffic and determine if it’s a signalized intersection. If it is signalized, listen to a few cycles of the light to try to get a good sense of traffic movement and alignment. Parallel traffic is usually, but not always, moving parallel to the crosswalk direction. Listening for the traffic on the perpendicular street, both moving traffic and waiting traffic, may also be useful for alignment. You want to listen for where the vehicles stop for the light. The stop line is supposed to be about 4 feet before the crosswalk line (further from the intersection). When you feel you are aligned for the crossing, and you’ve determined that the intersection is signalized, it’s usually necessary to leave that location and find a pedestrian pushbutton to call the pedestrian signal. So before looking for and using a pushbutton, align for the desired crossing and find a tactile landmark to return to before looking for the pushbutton. After pushing the pushbutton, you’ll return to the landmark and use it to re-align quickly.
Poles, grass edging, slope changes, angle of the curb, street edge or curb ramp can all combine to confirm the correct alignment. Asking other pedestrians may also be helpful.
If an APS is installed, the pushbutton locator tone may help you find the pushbutton and raised tactile arrow. The arrow on the APS is supposed to be aligned with the direction of travel on the crosswalk and can be used to confirm your travel direction and to confirm that you have found the APS for your crossing. They aren’t always installed correctly, so you must use all cues and information available to you to confirm your alignment at an unfamiliar location.
Be ready to adjust your alignment while crossing. Watch that you’re using straight-through traffic (not turning traffic) to align with while crossing. The raised edges of crosswalk markings, the slope and camber of the street, the traffic waiting on the perpendicular street, or a change in surface materials may help to refine your heading.
Where traditional cues aren’t effective, confer with local traffic and/or signals engineers to develop a treatment that provides the needed information, whether it is a landmark, beacon, guidestrip, or directional curb ramp(s) that can be relied on. Ask first about the intersection geometry, since there may be a good alignment cue nearby. There is some ongoing research on wayfinding cues, looking at tactile guide strips and modifications to APS to provide beaconing.
Your best strategy seems to be to take your time and use your experience and observation skills to analyze each situation carefully. If there are other pedestrians nearby, pay attention to what they are doing, and if you feel comfortable, ask for advice. Advocate for installation of the environmental changes that can assist you in locating crosswalks and aligning yourself properly for safe street crossings.