Tools to Reduce Crossing Distances for Pedestrians
Wide crossings can be barriers to children.
Elementary school children should not have to walk across wide, complex intersections like these for their school commute.
Wide, multilane roads are barriers to walking and bicycling to school. If children cannot cross multi-lane roads then they are, in essence, trapped in their neighborhoods, unable to walk or bicycle to school or to play and explore outside of their immediate neighborhood.
School walking routes and big roads do not mix. High-speed, busy, multilane roads are a barrier to walking and bicycling. In an effort to provide safe and accessible routes for children, such roads should mark the boundary of a school walking zone. Ideally, school attendance boundaries should be designated along the major arterial streets to avoid the need for young children to cross them, and schools should be built within neighborhoods, not on the other side of busy streets from students' homes.
The distance required to cross a street and the length of time that a pedestrian is exposed to traffic can be shortened with curb extensions and crossing islands. Curb extensions, also known as curb bulbs or bulb-outs, reduce the distance pedestrians must walk in the street, while crossing islands also simplify a crossing by breaking it into two pieces. Curb extensions are feasible at locations where full-time parking is allowed or shoulders are present.
Pedestrian bridge at Isaac Middle School in Phoenix, AZ. Image provided by Mike Cynecki.
Pedestrian underpass in Phoenix, AZ. Image provided by PBIC.
There are locations where a pedestrian bridge or underpass is the only way for pedestrians and bicyclists to cross the street, such as when children would otherwise be forced to cross freeways or major multi-lane arterial streets to get to or from school. However, the benefits of bridges and underpasses must be weighed against their substantial costs, which can be $2 million or more. The convenience of bridges and underpasses should also be considered. If they require pedestrians and bicyclists to follow an indirect path, they are unlikely to be used. Some schools station adult crossing guards at nearby bridges to ensure that students use them.
Curb extensions prevent motorists from parking too close to the intersection..
Curb extensions narrow the roadway and reduce the crossing distance by providing an extension of the sidewalk area into the parking lane. Shorter crossing distances are important for children, especially those with disabilities, because they tend to cross streets more slowly than adults. Curb extensions also bring pedestrians out from behind parked cars and helps pedestrians and motorists to better see each other. This is especially important for smaller children who are often invisible behind parked cars and may take longer to cross the street. For main streets, reducing the crossing time permits the green-light time for the major street traffic to be increased proportionately.[AASHTO, 2004]Curb extensions can also provide space for curb ramps, slow turning vehicles, and prevent motorists from parking on or near a crosswalk. Curb extensions must be designed to accommodate drainage. There are cases where curb extensions may not be needed or desirable on every leg of an intersection such as when the street leg is narrow, parking is not permitted, or the curb would interfere with a bicycle lane or the ability of fire trucks or other large vehicles to negotiate a turn.[AASHTO, 2004]
Treatment: Curb Extensions
The extension of the curb out from the sidewalk and into the street, typically at an intersection. Curb extensions increase pedestrian visibility and decrease pedestrian exposure distance in the street, crossing time and vehicle turn speeds. Curb extensions can also provide additional space for curb ramps.
- Better sight distances for pedestrians and motorists.
- Motor vehicles can not park in or too near crosswalks if curb extensions are properly designed.
- Increases motorist awareness of pedestrians.
Costs vary widely, ranging from $2,000 to $20,000, depending on details of design, drainage and movement or removal of utility poles or controller boxes.[PEDSAFE, 2004]
Keys to Success:
- Adequate lighting is needed to keep motorists from running into the curb extension.
Key Factors to Consider:
- Curb extensions work best when installed on streets that have on-street parking (parallel, diagonal or perpendicular).
- Curb extensions should be designed to accommodate large vehicles and bicycles, as appropriate.
- Drainage issue must be addressed.
- Number of crashes involving pedestrians.
- Severity of crashes.
- Speeds of through and right-turning motor vehicles.
Raised crossing islands simplify the crossing and provide a safe refuge in the street.
The pedestrian crossing island, also known as a raised median or refuge island, is a raised island placed in the middle of the street at intersections or midblock locations. The island separates crossing pedestrians from motor vehicles and narrows the travel lanes at that location. By breaking the crossing into two phases, crossing islands decrease pedestrian wait time, reduce crossing distance and allow pedestrians to focus on one direction of traffic at a time. Raised medians and pedestrian crossing islands are one of Federal Highway Administration’s nine proven safety countermeasures. Pedestrian crossing islands are effective techniques to reduce vehicle-pedestrian crash frequency and severity on multi-lane streets with both marked and unmarked crosswalks and on two-lane roads with and without a center left-turn lane (Bowman & Vecellio, 1994; Zegeer et al., 2002; Harkey et al., 2008; Chen et al., 2012).
Overall, crossing islands simplify and reduce the pedestrian exposure time to approaching motor vehicles at a crossing. These benefits are especially important for children, who tend to cross intersections more slowly and have less experience with crossings than adults. Crossing islands are designed with an opening that is level with the street to allow wheelchairs and pedestrians to cross through the island. Crossing islands improve safety at signalized intersections, providing refuge for those who begin crossing too late or are too slow to cross the entire street in one signal cycle (AASHTO, 2004).
While the crash-reduction safety benefits of pedestrian crossing islands and raised medians are well documented, evaluations of the impacts of pedestrian crossing islands on child pedestrians, particularly near schools, is limited. Such evaluations require being able to discern the unique safety effects of pedestrian islands within school crossing environments. Often streets near schools where pedestrian crossing islands are present also have special school signs and markings and crossing guards. This combination makes it difficult to isolate their respective safety contributions at a particular location.
Treatment: Crossing Islands
Raised medians in the middle of a street at an intersection, midpoint of the block, or continuously along street. They protect crossing pedestrians from oncoming traffic by serving as a barrier from motor vehicles, reduce crossing distance and allow pedestrians to focus on one direction of traffic at a time.
Significant reduction in pedestrian crashes on multi-lane streets and on multi-lane streets at unsignalized crossing locations.[Bowman & Vecellio, 1994; Zegeer et al., 2002]
Costs vary widely depending on the length and type of individual crossing islands, ranging from $6,000 to $200,000 (MTC, 2005). Continuous raised medians cost $15,000 to $30,000 per 100 feet depending on conditions.
Keys to Success:
- Most effective on high volume, multi-lane streets.
- Should be accessible to pedestrians with a visual impairment or in wheelchairs.
- Adequate lighting and markings can help to ensure driver awareness of crossing islands.
- Efforts should be made to slow traffic using advanced stop or yield lines and traffic calming measures for multi-lane pedestrian crossings (Leden, Garder, & Johansson, 2006).
Key Factors to Consider:
- Landscaping, utilities and maintenance issues must be addressed in the overall design.
- Can benefit motor vehicle safety as well by reducing head-on vehicular crashes.
- Potential business opposition due to loss of left-hand turn ability.
- May conflict with right-hand turns for large vehicles.
- Must be ADA-compliant
- Number of pedestrian crashes.
- Number of vehicular crashes — especially left-hand turns, angle-crashes at driveways and head-on vehicle-vehicle crashes.
Crossing Islands for Offset or Two-Stage Crossings
Two-stage crossing island at Sunnyslope High School in Phoenix, Arizona.
Another innovation in crossing islands is to stagger or offset the two halves of the crosswalk at the island. This further reinforces the concept of a two-stage crossing and separates the crossing of each direction of traffic. The median island is fenced and directs the pedestrian to face traffic once they reach the center island before crossing the second half of the street. The median island must be fully wheelchair accessible.
Diagrammatic sign on a two-stage crossing island in Phoenix, AZ. Image provided by Mike Cynecki.
A diagrammatic sign installed in a two-stage crossing island can be quite helpful in alerting pedestrians about possible dangers from moving vehicles when the closest lane of traffic stops.
For more information on staggered median visit PEDSAFE "Staggered Median" case study Tucson, Ariszona.
Waiting areas and stand-back lines keep students further back from busy streets when waiting to cross in Phoenix, Arizona.
Larger waiting areas and stand-back lines are low cost measures to improve safety at busy crossings. Large groups of students should not be waiting to cross immediately next to high-speed moving traffic. Waiting areas at crosswalks can be provided and “stand-back” lines painted to keep children further back from busy streets when waiting to cross.
When adequate waiting areas and stand back lines are provided, the adult school crossing guard should be the only person between the curb and the stand-back line. The stand-back line gives the guard something to point at when telling children to stand back from the street.
Treatment: Waiting Areas
Extra paving at busy crossings where large numbers of pedestrians can congregate before crossing the street without having to stand on landscaping, dirt or mud.
Waiting areas provide a separation between moving traffic and students, bicyclists and parents with strollers waiting to cross.
Costs range from $500 to $1,500 depending on the size of the additional waiting area.
Keys to Success:
- Working with schools to evaluate the crossing and making sure the waiting area is large enough to accommodate potential pedestrian volumes.
Key Factors to Consider:
- Potential need for larger sidewalk easement.
- Potential relocation of landscaping and/or utilities.
- Particularly valuable for sidewalks which don�t have separation to the adjacent raodway.
- Pedestrian capacity of waiting area.
Treatment: Stand-back Lines
A painted line on the sidewalk at a crossing, typically 5 to 10 feet from the back of the curb line, which pedestrians wait behind before crossing.
Increases pedestrian safety by increasing the distance between waiting pedestrians and vehicular traffic. The line also gives something for the crossing guard to point at when telling students where to wait before it is safe to cross the street.
Stand back lines are extremely inexpensive, with an average cost of $50. However, the lines may need repainting annually.
Keys to Success:
- Ensuring a large enough waiting area, but stand back lines can also be effective on narrow sidewalks.
Key Factors to Consider:
- Ensuring the stand-back line is in good condition (visible) at the start of each school year. Colors for blue-stake markings should not be used.
- Pedestrian-vehicle conflicts.
Putting It Into Practice: Student Waiting Areas and Stand Back Lines
These images highlight the differences before and after a waiting area and stand-back line were installed at RE Miller Elementary School in Phoenix, AZ.
Unfortunately, many school crossings are at busy streets, and many of the sidewalks in Phoenix were built prior to the time when sidewalk buffer areas were required as a part of the design to separate pedestrians and motor vehicle traffic. It is important to provide a separation between moving vehicles and young children waiting to cross a busy street. This is not possible with a five foot-wide sidewalk.
One such school crossing was identified by the Washington Elementary School District in northwest Phoenix. This is a crossing for RE Miller Elementary School for nearly 100 children over a busy five-lane street with nearly 40,000 motor vehicles per day. Despite the presence of two crossing guards and a 15 mph school zone, the school district expressed a concern about the large groups of children waiting on a five-foot wide sidewalk before crossing.
The school district, City, and property owners worked together on a solution to provide a safe area for students to wait. The property owner (church) provided an easement to build a 10 ft by 20 ft waiting area behind the sidewalk. The school district moved the existing wood fence behind the new student waiting pad, and the City modified the landscaping behind the sidewalk, poured a concrete pad for students, and placed a ‘Stand-Back’ line between the sidewalk and student waiting area. These low-cost and low-tech measures provided a considerable safety benefit at the crosswalk. Since then, Phoenix has built nearly 80 student waiting areas at major crossings where large numbers of students congregate before crossing. Even more of the painted ‘stand-back’ lines have been installed at numerous school crossings.
This example illustrates that you do not have to spend a lot of money to obtain a big safety dividend. Some of the least expensive measures can have a big impact on safety.
In this image, the pedestrians have crossed over the first of two lanes. The driver in the inside lane has stopped to let them cross. However, the driver in the outside lane has not seen the pedestrians and is still moving.
This four-lane road is difficult for pedestrians to cross before the road diet.
This shows the same road converted to three lanes plus bicycle lanes after the road diet.
Pedestrian crossing islands can be added in the center lane at select crossing locations.
A “road diet” occurs when one or more travel lanes or parking lanes which primarily serves motor vehicles is reallocated to serve another mode of travel. This most commonly involves converting an undivided four lane roadway into three lanes made up of two through lanes and a center two-way left turn lane with bicycle lanes added. The reduction of lanes allows the roadway to be reallocated for other uses such as bicycle lanes, pedestrian crossing islands, and/or parking (Proven Safety Countermeasures). The road diet is recognized as a proven safety countermeasure by the Federal Highway Administration. Studies demonstrate that road diets reduce vehicle-to-vehicle and pedestrian-to-vehicle crashes and lower vehicle speeds [Huang, Stewart, & Zegeer, 2002; Harkey et al., 2008; Chen et al., 2012; PEDSAFE, 2004 Ch. 5; Gates et al., 2007; Keuper, 2007]. Street crossings are safer for pedestrians when there are fewer lanes to cross because a pedestrians’ exposure to traffic is reduced. Multiple-lane threat is a problem that arises when pedestrians have to cross more than one lane in each direction. A multiple-threat pedestrian crash is a crash type that occurs when a motor vehicle in one lane stops and provides a visual screen to the motorist in the adjacent lane. The motorist in the adjacent lane continues to move and hits the pedestrian. This type of collision, where the pedestrian is hit in the second, third or fourth lane is common on multilane roads and typically results in a serious injury or death producing collision due to a higher impact speed. Additionally, providing advance yield lines or stop lines as well as crossing islands also reduce the risk of a multiple threat crash, as discussed later in this chapter.
By decreasing the width of the road and number of travel lanes that pedestrians must cross, a road diet helps lower vehicle speed and reduces the multiple-lane threat to pedestrians. In settings with large numbers of children, speed management has great potential for injury prevention. Pedestrian crashes involving a child most often result from the child’s error, thus slower speeds give motorists more time to react and can lessen injuries when crashes do occur [Retting, Ferguson, & McCartt, 2003].
While road diets offer motorist and the general pedestrian population certain safety benefits, there is little research that has specifically examined the impact of road diets on children. Children face special challenges to safely cross a multi-lane street such as impulsiveness; slower walking speeds; small body size that limits their visibility; less experience with traffic and still-developing cognitive abilities that make it difficult to accurately judge vehicle speed and traffic stream gaps [Rodergerdts et al., 2010; Fitpatrick et al., 2006]. These factors lend support for considering the need for adult supervision such as parents, caregivers or crossing guards at street crossing locations near elementary schools during arrival and dismissal times.
Road diets can be low cost if planned in conjunction with reconstruction or pavement overlay projects, since a road diet mostly consists of reallocating roadway space with restriping. More capital-intensive conversions can include curb realignments or addition of center medians or median islands. If curbs are realigned, space can be allocated to green space or other buffers or to increase sidewalk width. Roadways with Average Daily Traffic (ADT) of 20,000 or less may be good candidates for a road diet and should be evaluated for feasibility [Proven Safety Countermeasures, Road Diet; HSIS, 2010]. Most studies indicate that roadways were able to maintain vehicle capacity after the road diet was installed, [Harkey et al., 2008; Gates et al., 2007; Keuper, 2007], [ITE, 2010; HSIS, 2010], although one report found some delays during peak travel hours [Knapp & Giese, 2001]. Three-lane roadways, like those created by road diets, can improve emergency response by creating space, via a two-way center turn lane, for emergency vehicles to bypass congestion [Daisa, 2010]. Driveway density, transit routes, the frequency and design of intersections along the corridor, as well as operational characteristics are some considerations to be evaluated before deciding to implement a road diet [Proven Safety Countermeasures, Road Diet].
The next three images illustrate the “diet” applied to a four-lane roadway that is difficult to cross. Pedestrians must cross four travel lanes, there is no center pedestrian crossing island, no buffer between the road and sidewalk, and there is no designated space for bicyclists. Additionally, it is difficult for motorists to make left turns into the driveways and side streets along this road.
Through the road diet, the roadway has now been reduced from four lanes to three lanes, one lane in each direction, plus a two-way center turn lane. There is now room to install bicycle lanes, and the bicycle lanes create a sidewalk buffer for pedestrians. This road diet was accomplished with paint, which has a relatively small cost and requires no construction.
A much better pedestrian connection along this roadway is now possible. The restriping of this roadway improves pedestrian crossings along the entire corridor since pedestrians only cross two through lanes, versus four lanes of travel. This roadway configuration also allows for the placement of crossing islands at some locations, which provide the pedestrian a refuge and allow the pedestrian to focus on traffic from one direction at a time. Adjacent residents and businesses also benefit from this change because left turns into and out of their property are now easier. Thus, road diets can benefit pedestrians, bicyclists, motorists, and adjacent businesses.
Treatment: Road Diets
Road diets are reductions of lanes on multilane roadways that can reduce crossing distances as well as motor vehicle speeds, providing safety benefits to pedestrians, bicyclists and motorists. Road diets can also redistribute space to bicyclists and pedestrians by creating room for bicycle lanes and sidewalks.
Narrowing roadways and/or reducing the number of lanes that pedestrians are required to cross can result in slower motor vehicle speeds and reduced crossing exposure time, respectively, corresponding to a reduction in pedestrian crashes.
Costs vary depending on the scope and scale of the road diet. The cost of restriping a four-lane street to one lane in each direction, a two-way left-turn lane, and bicycle lanes is about $5,000 to $20,000 per mile, depending on the number of lane-lines that must be repainted. Net costs may be lower for road diets when re-striping a roadway after a resurfacing project. The cost of adding sidewalks and raised medians is much higher, estimated at $100,000 per mile or more.
Keys to Success:
- Considerations must be made for overall safety and roadway capacity operation.
- It is also desirable to include the entire affected area in the decision-making process.
Key Factors to Consider:
- Reducing the number of lanes may result in lower motor vehicle capacity and increased delay for motorists in some situations.
- A level-of-service analysis should be conducted to determine whether the number of lanes on a roadway is appropriate and how alternative routes will be impacted by a road diet.
- Reduction in motor vehicle speed or reduction in crashes and/or crash severity involving crossing pedestrians or bicyclists.