Road Design for Vulnerable Road Users

Vulnerable road users generally refer to those modes of travel that do not include cars, public transport, or licensed commercial vehicles. It includes both nonmotorized travel and motorcycles.

Motorcycle and moped use are on the increase. An emerging form of personalized travel is the use of e-scooters, which are being used extensively in several countries. These offer a solution to growing traffic congestion, parking problems, and the high cost of private car ownership.

Footpaths/Footways:

• To promote a safe environment for walking, pedestrians must be provided with a complete network with sufficient space to walk along the public right-of-way.
• In urban and suburban areas where pedestrian volumes may be high, the most common form of provision is the inclusion of a paved or sealed footway immediately adjacent to, and raised above, the vehicular carriageway.
• If speed and volumes are low, then less segregation and protection are necessary, and in certain instances the vulnerable users may dominate the street space.
• 1.8m is considered the absolute minimum clear width to allow pedestrians to pass each other without having to move into the vehicular path. Increased width may be needed as pedestrian flows increase to prevent overspill into other use areas (i.e., cycle lanes or traffic lanes).
• A positive crossfall toward the roadway is required on footways to assist drainage. Typically, this is 2.5 percent or 1 in 40, although lower gradients may be used in areas with harsh winters and ice. Gradi-ents greater than 3.3 percent (1 in 30) make it difficult to walk on, particularly when pushing strollers or for wheelchair users.
• The width of footpaths, a necessity for safe footpaths, is primarily determined by the type and density of land development and the volume and needs of pedestrian and vehicular traffic. Typically, these are expressed in different levels of service for pedestrian footpaths based on flow rates, space per person, and description of flow.
• In addition to the minimum passing width noted above, it is also necessary to consider the adjacent land uses and the likelihood of encroachment into the clear pedestrian route.
• Footways should be raised above the vehicular carriageway by at least 75 mm, with a defined boundary on both sides.
• If motorists are known to regularly mount the edge of a footway along a length of curbline, the use of a high curb face should also be considered as an alternative to using a line of bollards. A curb face of 125 mm–140 mm will usually stop motorists mounting the edge of the footway when stopping.
• It is crucial that the footpath is not obstructed for pedestrian use and to understand the characteristics of the full range of the pedestrian population that may use the facilities to ensure the design of pedestrian facilities accommodates the range of pedestrian abilities.
• Pedestrians have a wide range of characteristics and needs, such as walking speed, spatial needs, mobility issues, and cognitive abilities. They need clear guidance for safe routes and identification of conflict points with vehicles, for example, the use of tactile paving and a visual contrast of surfaces.
• Pedestrian facilities need to be regularly maintained to ensure their safety and function.
• In rural areas, where pedestrian traffic might be less frequent, walkable shoulders may be sufficient where vehicle flows are high. Care will also be needed to ensure that these shoulders do not become running or stopping lanes that might endanger pedestrian use.
• For low vehicle flows and low speeds, no provision of separate footways may also be an appropriate solution, but care is needed to both manage vehicle speed and make sure that vulnerable users are not hidden by the alignment.
• Separate trails or shared-use paths can safely convey pedestrians along rural routes either adjacent to the vehicle route or completely separately.
• On rural routes, and particularly on high volume urban highways, adequate separation and protection for the pedestrian route are essential.
• Ideally pedestrian routes should be separated to the rear of the clear zone to minimize impact from errant vehicles
• A buffer zone between pedestrian movement and vehicles can be provided for signage, lighting, or planting. Care should be taken that these do not form roadside hazards.
• If segregation is not possible, then an adequate vehicle restraint system needs to be provided. This may also deter pedestrians from crossing the route; however, additional measures may also be necessary to prevent unsafe interaction between pedestrians and traffic and safe convenient crossing points provided to deter the unsafe crossing.
• Pedestrians and vehicles are able to share the same space safely where speeds are less than 20km/h. In these shared zones, pedestrian movements have equal priority with vehicles and vehicle speeds are low. Often this is a result of the high number of pedestrian movements compared to vehicles. Crucially these are not major transport corridors, and alternative through routes for vehicles must be available.
• At speeds of 30 km/h, separate provision needs to be made where frequent pedestrian use is expected.

Pedestrian Crossings:

A crucial aspect of designing a safe and accessible pedestrian route is adequately dealing with crossing requirements of the motorized corridor. This can be done in several ways that are dependent on the concentration and volume of pedestrian and vehicle movements.

Often pedestrians need to be guided to appropriate crossing points or deterred from crossing in unsafe locations. This is often achieved by using pedestrian fencing or guardrails close to the curb edge. Unless alternative safe crossing points are available that are perceived as being convenient to use, any barriers may soon become damaged or stolen to recreate the more direct (even though dangerous) crossing point.

When considering pedestrian crossings at intersections, the ability to cross the minor road safely is as important as the crossing of the main road in order to provide consistent route continuity for pedestrians. The level of provision on the minor road need not be the same as on the major road, but it is usually safer to maintain the same level of control on each arm.

Additional consideration may need to be given at school crossing locations given the extra vulnerability of children. This may include lower speed zones, additional signage, enhanced crossing facilities, or even crossing supervisors. Equal consideration needs to be given to pedestrians’ crossing of minor roads and accesses away from formal junctions.

Grade-Separated Pedestrian Crossing:

• Grade-separated crossings whether under or over roadways, are expensive pieces of infrastructure to install and need to be justified by demand and provide convenient crossing, otherwise they will be ignored.
• Where high volumes of pedestrians are concentrated in specific locations particularly on high-speed dual carriageways in urban environments, grade-separated crossings can be appropriate, either as a pedestrian overbridge or underpass. They involve separating pedestrians from traffic by placing them at different levels and are often used where pedestrian crossing signals would cause delays and queueing or crashes (due to high traffic speeds). Pedestrian overpasses and underpasses require users to deviate from their preferred desired line—a direct crossing from A to B. Pedestrian route selection is typically determined by the shortest, fastest, or most convenient route.
• Any deviation from this straight line, either vertically or horizontally, reduces the attractiveness of that route and increases the likelihood that it will not be used. Closure or obstruction of the direct route is needed to encourage use of the safer alternative.
• Ideally these facilities should have ramps rather than steps to accommodate the mobility impaired, but this often increases the length of any diversion.
• Clear sight lines on approach and through the crossing and sufficient lighting must be provided with no places for people to hide, as they can be seen as a security hazard with the opportunity for personal attacks, especially at night.
• The risk of personal attack reduces their attractiveness and increases the likelihood that crossings will not be used.
• To be effective they need very careful design and location to ensure ease of access. They also require sufficient lighting, adequate drainage, and proper maintenance to keep them in clean and tidy conditions.
• Often the provision of planned retail or vendors is good for increased security. Such design should be encouraged.
• Once constructed they cannot easily be moved to accommodate changing movement patterns
• For underpasses it is possible to use a reduced height (2.5 m) and raise the carriageway by a maximum of 1.5 m, as well as lowering the footpath to reduce both cost and impact.

Signalized/Controlled Pedestrian Crossing:

It is much easier to provide maintain the same level as the rest of the route, but then this requires segregation in time, i.e., specific times for pedestrians and vehicles to use the same space.

• Signalized pedestrian crossings at intersections aim to reduce vehicle/pedestrian conflicts.
• They provide right-of-way access to pedestrians during a green pedestrian phase when conflicting or all traffic is stopped.
• At intersections with high pedestrian volume, it is also common to treat them as scramble intersections, where pedestrian movements from all directions are allowed in a single green phase, including diagonal movements.
• Pedestrian green time should be timed to give pedestrians long enough to complete their crossing before the signals change to allow vehicle traffic to start passing through the crossing again. (Assume pedestrian walking speed 1.2 m/s.)
• Long waiting times for pedestrians can increase the likelihood of violations.
• Sufficient time is needed for pedestrians to clear the crossing before traffic can start when neither movement is permitted to start (blackout period or “all red”).
• There can be compliance issues with vehicles failing to obey signals or failing to give way when turning at signals is a common issue. A lead phase can be included at signals to give pedestrians an early start at signals before other road users are allowed to start. This is useful to reduce the incidence of turning vehicles striking pedestrians at intersections, as this gives greater visibility to crossing pedestrians.
• Tactile paving should be provided to guide the visually impaired pedestrians through the crossing, and parking should be removed from the immediate vicinity of the crossing to provide adequate sight lines.
• To maintain the safety and segregation of uses, it is important that filter lanes are omitted where pedestrian crossings are in place.
• Countdown timers at signals can also provide phase duration information to pedestrians. The timers display the time remaining until the end or start of a pedestrian green phase and remove some of the doubt for all users.
• In addition to signalized crossings, other crossings that give priority to pedestrians typically consist of signs and painted road markings (“zebra crossings”).
• These formalize the crossing location giving pedestrians the right-of-way over vehicles. They also increase the awareness for other road users that pedestrians may be present, improving expectations about the need to stop.
• They also cater for the mobility impaired with footways ramped down to carriageway level or the carriageway lifted to footway level.
• Audible and tactile warning of the pedestrian crossing phase can also be provided on the traffic signal pole.
• Especially where vehicle approach speeds are high, at-grade raised pedestrian crossings can improve safety, but need to be clearly signed and have sufficient advance warning for drivers to react to their presence.
• Extra care is required when designing signalized pedestrian crossings either at intersections, or away from intersections, in higher-speed, multi-lane environments. Vehicles may fail to stop either because they fail to see the signals or do not comply, and this results in high severity outcomes.
• Raised pedestrian crossings have a similar profile and speed reduction effect as flat top speed humps (safety platforms), but they differ in that they give priority to pedestrians rather than motorists.
• They consist of a raised platform with a marked pedestrian crossing on top.
• The raised crossing serves the purpose of slowing vehicles, as a speed hump or platform, but also increases the visibility of pedestrians due to the increased height.
• As they are raised to footway level, they do not need a ramped approach but still need tactile paving to assist the blind and partially sighted.
• Other speed reducing features can be used in advance of pedestrian crossings and typically result in a lower likelihood of a crash occurring, and lower severity when collisions with pedestrians do occur.
• Narrowing of the roadway can also provide a safety benefits as pedestrians have less distance to cross, facilities can be included to make pedestrians more visible, and speeds may be reduced. Alternatively, the crossing movement can be split into two with provision of a protected median or refuge for pedestrians (also see uncontrolled crossing section below).

Uncontrolled Pedestrian Crossing:

• Wide crossings (of more than two lanes) can be narrowed by providing central refuge islands to limit the amount of time pedestrians are exposed to traffic.
• Pedestrians and drivers need to maintain alertness where pedestrians are crossing multilane roads, as they are often hidden from drivers’ view, and vice-versa, by vehicles in adjacent lanes.
• Pedestrian refuges are raised median islands in the middle of the road that provide an area for pedestrians to safely wait until an appropriate gap allows them to cross
• Islands need to be wide enough to protect pedestrians with strollers (and cyclists) from passing traffic (1.8 m).
• This simplifies the crossing maneuver for pedestrians by creating the equivalent of two narrower one-way streets instead of one wide two-way street.
• Refuges are particularly useful for those who are wheelchair-bound, elderly, or otherwise unable to completely cross the road in one movement.
• Islands can also have additional benefits, including acting to separate traffic moving in opposite directions, controlling vehicle speeds by narrowing the roadway, and providing motorists with an indication of where pedestrians might cross a roadway.
• Footway ramps with tactile paving need to be included to make them appropriate for all mobility conditions.
• Refuges alone do not give any priority for pedestrians to cross.

Cyclists Facilities:

• Limiting conflict between cyclists and other cyclists, pedestrians, or motorists.
• Ensuring low-stress environments where mixing with other users is limited and controlled.
• Separating main routes for cyclists from pedestrian routes.
• Reducing motor vehicle traffic volumes and speeds around cyclists, especially when road users mix.
• Separating cyclists from fast/heavy motorized traffic, reducing the number of dangerous encounters—including separation on routes and/or at intersections and on-street parking.
• Ensuring conflict points at intersections and crossings are clearly presented so that users are aware of the risks and can adapt behavior appropriately.
• Visibility of cyclists to motorists should be maximized at the approach to intersections.
• Ensure cycling infrastructure is well maintained— especially quality of pavement and continuity through intersections. Wide shoulders may be pro-vided to allow for cyclists’ use, along with protection from vehicular traffic using shoulder rumble strips or physical barriers.

Cycle lanes:

• When the design of the cycle lane follows best practice and implementation is part of a coherent network, cycle lanes offer a safe and convenient route for people who cycle to travel around a city.
• In rural areas, cycle lanes can also be provided on the paved shoulders.
• They should only be applied on streets with medium or low motor vehicle volumes and speeds.
• Where vehicle speed and/or volume are high, then separate cycle lanes should be used.
• Cycle lanes should be wide enough for people who cycle to feel comfortable and safe, allowing for comfortable clearance of other users, with surfaces smooth and level.
• Minimum recommended width is 2.5 m for a single direction.
• Clear markings and accompanying signage should be in place to increase the visibility of the cycle lanes.
• Buffer zones may be considered between the cycle lane and motorized traffic where safety is of concern, particularly where there is heavy freight traffic.
• Buffer zones between the cycle lane and parked vehicles are strongly recommended.
• Cycle lanes separated from motorized traffic simply by painted road markings lead to parking and moving traffic encroachment

Intersections:

Good design will generally include the following principles:

• Avoid mixing motor traffic with cyclists where the traffic flow and/or speed is typically high.
• On carriageways with low traffic volumes and low traffic speeds (typically 30 km/h or less), cyclists usually mix with other road traffic, and cycling specific infrastructure is typically not necessary at intersections.
• Maximize separation of cyclists from dangerous traffic movements.
• Separate traffic light phases for people cycling and people motoring or separate routes by over/ underpasses.
• Maximize the visibility of cyclists.
• Make drivers aware of cyclists on the approach to an intersection.
• Use bike boxes and advanced green lights to allow cyclists to proceed through an intersection ahead of other road traffic.
• Intersections should be easy to identify, under-stand, and safe to use by all transport users. This requires specific designs to underline the priority status of cyclists.
• For any type of intersection, the primary consideration for safety is visibility of cyclists.
• In situations where cyclists and motor traffic are approaching the intersection in close vicinity (i.e. cycle lanes or mixed traffic), it is assumed that drivers are aware of cyclists.
• In situations where cyclists are separated from the carriageway, it is advised that the cycle path should be designed alongside the carriageway on the approach to the intersection to increase drivers’ awareness of cyclists.
• Advanced cycle stop line/bike box gives cyclists advantage away from signal stop lines.
• Turning provisions may be needed at intersections for motorized vehicles cutting through cycle lanes to ensure cyclists are highly visible. This includes colored road surfacing for the cycle lane and additional signage.
• Right-of-way intersections are the simplest intersection solution on roads with low traffic intensities, while signalized intersections are recommended when a cycling route crosses a main road with high traffic volumes, and particularly if there are multiple lanes.
• Single lane roundabouts are usually a safer alternative to signalized intersections due to the lower speed environment these create and reduced conflict points, although they cannot handle as many vehicles.
• When a busy cycle route crosses a main road with high traffic volumes, a grade-separated crossing is preferred.