Pedestrians Chap 21

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P A R T IV

NON-AUTOMOBILETRANSPORTATION

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21.3

CHAPTER 21

PEDESTRIANS

Ronald W. EckDepartment of Civil and Environmental Engineering,

West Virginia University, Morgantown, West Virginia

21.1 INTRODUCTION AND SCOPE

A pedestrian is defined as any person on foot. While everyone is a pedestrian at one timeor another, in the United States walking is viewed primarily as a recreational activity. How-ever, for relatively short trips, walking can be an efficient and inexpensive mode of trans-portation.

There are many factors that influence choice of travel mode and, specifically, the decisionto walk. The National Bicycling and Walking Study (FHWA 1992) showed that there is a

three-tiered hierarchy of factors:

1. Initial considerations. Many people rely on their automobile to go virtually anywhere andnever seriously consider the option of walking. An individuals attitudes and values alsoplay a rolee.g., walking may be considered as not cool. Perceptions are also impor-tant in the decision to walke.g., safety concerns about traveling at night. Finally, thereare situational constraints that, if they do not preclude the decision to walk, they do requireadditional planning and effort. Examples include needing a car at work or having to pickup children from soccer practice.

2. Trip barriers. Concern for safety in traffic is a frequently cited reason for not walking.This is particularly true where there are no alternatives to walking along high-speed, high-volume roadways. There may be problems with access and linkage, e.g., lack of connec-

tions between neighborhoods and shopping areas or parks. Environmental factors such asrugged topography or extremes in weather can also be considered as barriers.

3. Destination barriers. Lack of support from employers or coworkers can act as a barrier,e.g., relaxing the dress code or establishing a policy of flextime.

Increased levels of walking can result in benefits in terms of health and physical fitness,the environment, and transportation. Studies have demonstrated that even low to moderatelevels of exercise, such as regular walking, can reduce the risk of coronary heart disease,stroke, and other chronic diseases, help reduce healthcare costs, and contribute to greaterfunctional independence in later years and improve the quality of life at every stage. Re-placing automobile trips with walking trips could result in significant economic benefits.

Since it is nonmotorized and nonpolluting, walking would result in reduced emissions, energy



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21.4 CHAPTER TWENTY-ONE

consumption, and congestion. Facilitating walking means additional travel options for thoseunable to drive or who choose not to drive for some trips. Where there is a truly intermodaltransportation system in which walking is an important component, the livability of com-munities is enhanced.

Passage of the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) helped

focus new attention on walking as an important nonmotorized mode of transportation. ISTEArequires each state and metropolitan planning organization (MPO) to include nonmotorizedelements in its transportation plans.

ISTEA has opened up new sources of potential funding for nonmotorized transportationimprovements, planning, and programs as well as for recreational trails and intermodal link-ages. With these funding programs and the planning requirements established by ISTEA,there is increased interest in pedestrian transportation.

This chapter takes a comprehensive look at incorporating pedestrians into the transpor-tation system. While the chapter provides an overview, it also directs readers to sources ofmore detailed technical information.

21.2 CHARACTERISTICS OF PEDESTRIANS

21.2.1 Ambulation

In normal walking, the lead foot swings forward and, as it approaches the end of the stride,the heel comes down on the surface gently as the ankle allows the foot to rotate forward ata controlled rate until the sole also contacts the floor. There is little horizontal force appliedduring the heel-strike phase, but if the heel edge slips at this point, the leading foot slidesforward. Therefore, the characteristic slip pattern is that the victim falls backwards. Thistype of fall usually results in the most severe injury. Forward slips may occur when the soleof the foot slides in the retreating portion of the step. This tends to produce a forward fall

where the injury is often less severe. Many slips result from the more complex activities ofturning and changing direction. In these instances, the fall pattern is less predictable.A trip occurs when a pedestrians foot is impeded in the walking process by striking

against some obstacle in the path of travel. If the interruption of motion is great enough, thepedestrian will fall forward. The persons reflex action is to extend the upper arms to absorbthe energy of impact. Falling onto the extremities in this fashion can cause injury to wrist,forearm, elbow, upper arm and shoulder. One or both of the knees may also strike the ground.

Pedestrians tend to look ahead to their objective; the normal line of sight is about 15 below horizontal relative to the eyes. Pedestrians do not usually look down deliberatelyunless something attracts their attention. Consequently, even small changes in surface ele-vation or characteristics are not always seen. However, even if someone is looking down atthe surface, a problem may not be perceived. Color, texture, low light levels, and glare can

obscure changes in walking surfaces.Good design takes this human factor into account in two ways. First, many problems canbe avoided by giving thoughtful attention to safety in facility planning, design, and construc-tion. Second, where something cannot be avoided, e.g., a single step, the designer must buildin visual and tactile cues that will cause the pedestrian to look down and see the hazardbefore tripping over it or slipping on it.

Another characteristic of pedestrians is that they will always take the least energy route(i.e., the shortest distance and flattest path) between two points. They tend to cross streetsat the most convenient locations rather than at designated crossings. If it is easier to crossat mid-block than to walk a long distance to a corner crosswalk, pedestrians will take themost direct route and cut across the street between intersections. Where a choice of routesis available, substantial barriers may be needed to prevent pedestrians from taking the direct

route where that route includes hazards (e.g., at-grade crossing of a busy arterial roadway).



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PEDESTRIANS 21.5

According to the American Association of State Highway and Transportation Officials(AASHTO) roadway design policy (2001), pedestrians usually do not walk over 1 mile towork or over 0.5 mile to a transit stop. About 80 percent of the distances traveled bypedestrians will be less than 0.5 mile. Pedestrian volumes are influenced by conditions suchas weather, advertised sales, or special events.

Effective pedestrian facilities are designed to accommodate the full range of users. Thereis no such thing as a standard pedestrian. The stature, travel speeds, endurance limits, phys-ical strength, and judgment abilities of pedestrians vary greatly. Users include children, olderadults, families, and people with and without disabilities. Pedestrians may be carrying pack-ages or luggage, walking a dog, pushing children in strollers, or pulling delivery dollies.Pedestrians transporting items cannot react as quickly to potential hazards because they aremore physically taxed and distracted.

21.2.2 Seeing and Being Seen

Visibility of a pedestrian in the traffic stream is influenced by environmental conditions,

behavior, and attire. The key factor is the degree of contrast between the pedestrian and hisor her environment.Environmental factors can affect the visibility of pedestrians to motorists. Rain, snow,

fog, shadows, and glare all reduce visual range and acuity. The National Highway Institutes(NHI) Participant Workbook (NHI 1996) notes that vehicles themselves are equally impor-tant. Dirty or cracked windshields not only reduce vision but magnify the effects of glare.

There are also visual screens in the driving environment. Moving vehicles, particularlybuses and commercial vehicles can block pedestrians and motorists view of one another.Stationary features such as parked vehicles, shrubs, structures, and traffic signal controllerboxes can have the same effect.

About one-half of fatal pedestrian crashes occur in low-light or dark conditions. At night,pedestrians are frequently difficult to see because they lack conspicuity. All of the factors

affecting conspicuity become increasingly critical during times of reduced light or darkness.For example, according to Federal Highway Administration (FHWA) data, at night the av-erage driver of a vehicle operating with low-beam headlights will see a pedestrian in darkclothing in the roadway about 80 feet in front of the vehicle. At speeds greater than about20 to 25 miles per hour, drivers do not have enough time to perceive the pedestrian, identifyhim or her, and make a decision to stop or swerve in time to avoid striking him or her.

Pedestrians tend to overestimate their visibility to motorists. Motorists who have beeninvolved in nighttime crashes with pedestrians often remark, I dont know what I hitIthought I struck an animal. This is an indication they did not see the pedestrian until it wastoo late to react.

21.2.3 Groups of Particular Concern

Older Adults. By 2020, it is estimated that 17 percent of the U.S. population will be olderthan 65. Although aging itself is not a disability, most persons aged 75 or older have adisability. Many of the characteristics commonly associated with aging can limit mobility.The aging process often causes a general deterioration of physical, cognitive, and sensoryabilities. Characteristics may include:

Vision problems such as degraded acuity

Reduced range of joint motion

Reduced ability to detect, localize, and differentiate sounds

Limited attention span, memory, and cognitive abilities



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Reduced endurance

Decreased agility, balance, and stability

Slower reflexes

Impaired judgment, confidence, and decision-making abilities

Older adults generally need more frequent resting places and prefer more sheltered en-vironments. The FHWA publication (1999) on designing pedestrian facilities for access notesthat many have increased fears for personal safety. Statistics confirm these fears indicatingthat older pedestrians appear to be at increased risk for crime and crashes at places with nosidewalks, sidewalks on only one side, and places with no streetlights. Older pedestrianswould benefit from accessible paths that are well-lit and policed.

Ambulation of older adults is affected by their reduced strength. Travel over changes inlevels, such as high curbs, can be difficult or impossible for older adults.

Because older people tend to move more slowly than younger pedestrians, they requiremore time to get across the street than many other sidewalk users. For many years, engineershave designed traffic signals based on an average pedestrian walking speed of 4 feet per

second. Using a walking speed of 2.8 feet per second better accommodates older pedestrians.The reduced visual acuity of older people can make it difficult for them to read signs ordetect curbs. Older people are more dependent on high contrast between sign backgroundsand lettering. Contrast resolution losses can cause them to have difficulty seeing smallchanges in level, causing trips and falls on irregular surfaces.

Children. Children have fewer capabilities than adults due to their developmental imma-turity and lack of experience. Compared to adults, children tend to exhibit the followingcharacteristics:

One-third less peripheral vision

Less accuracy in judging speeds and distances

Difficulty in localizing the direction of sounds

Overconfidence

Inability to read or comprehend warning signs and traffic signals

Unpredictable or impulsive actions

Trust that others will protect them

Inability to understand complex situations

Disabled. According to the 1990 Census, one in every five Americans has a disability. Infact, 85 percent of Americans living to their full life expectancy will suffer a permanentdisability. People with disabilities are also more likely to be pedestrians than other adults

since some physical limitations can make driving difficult. According to the FHWA publi-cation on providing access (1999), disabilities can be divided into three categories: mobility,sensory, and cognitive.

People with mobility impairments include those who use wheelchairs, crutches, canes,walkers, orthotics, and prosthetic limbs. However, there are many people with mobility im-pairments who do not use assistive devices. Characteristics common to people with mobilitylimitations include substantially altered space requirements to accommodate assistive deviceuse, difficulty in negotiating soft surfaces, and difficulty negotiating surfaces that are notlevel.

Although sensory disabilities are more commonly thought of as total blindness or deaf-ness, partial hearing or vision loss is much more common. Other types of sensory disabilitiescan affect touch, balance, or the ability to detect the position of ones own body in space.

Color blindness is considered a sensory defect.



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PEDESTRIANS 21.7

Cognition is the ability to perceive, recognize, understand, interpret, and respond to in-formation. It relies on complex processes such as thinking, knowing, memory, learning, andrecognition. Cognitive disabilities can hinder the ability to think, learn, respond, and performcoordinated motor skills. Such individuals might have difficulty navigating through complexenvironments such as city streets and might become lost more easily than other people.

The aforementioned FHWA publication (1999) on designing for access presents an ex-cellent overview of the characteristics associated with different types of disabilities. Thepublication also reviews design approaches for accommodating specific categories of disa-bilities.

21.3 PLANNING

21.3.1 Conceptual Planning

Conceptual planning is relatively simple, consisting of determining the general direction that

walkways should take. Focus should be on pedestrian generators such as schools, shops,cultural attractions, and work and play places. First, look at routes that presently exist beforeestablishing new ones. Privacy, views, access, and local character must be understood andincorporated into the planning.

Initially, planners should determine where people want or need to travel, the routes theymight travel, and who these people are. The most likely users of improved pedestrian facil-ities are:

Children who must be driven to school, play, and other activities.

Parents who have to drive children and would appreciate safe walking routes so theirchildren can move around the community by themselves.

Older people who may not drive but have time to walk may be able to carry out some oftheir daily chores, enjoy the outdoors, and exercise all on the same trip.

Commuters who may be able to walk to bus or carpool stops.

Recreational users, especially those who jog or walk regularly, would benefit from im-proved routes and separation from fast-moving traffic.

Simple pedestrian volume counts usually do not yield enough information about wherepeople are going or coming from, trip purpose, and any special pedestrian needs that shouldbe met. Such data are best obtained through an origin/destination survey that should includethe following information:

1. Location of major pedestrian generators such as parking facilities, transit stations, andmajor residential developments

2. Location of significant pedestrian attractions such as shopping centers, office and publicbuildings, theaters, colleges, hospitals, and sports arenas

3. Existing and potential pedestrian routes between major destinations

4. Time periods in which major pedestrian flow occurs

Some questions to consider include:

1. Do existing routes satisfy the heaviest travel demand? Can a need for new routes beclearly identified?

2. Do existing routes require improvement to resolve circulation problems?



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3. Which areas seem to be preferred locations for development of new activities to generatepedestrian movement?

21.3.2 Access and Linkages

There is no question that transportation modes have influenced the way cities have grownand the forms they have taken. Before the advent of the automobile, cities were more com-pact in terms of area and population. However, in the United States the automobile clearlyis the dominant transportation mode. One manifestation of this is the phenomenon of sub-urbanization that occurred after World War II. Characteristics of suburbs include:

1. Suburban land use planning encourages low density and separation of land use types.

2. Street design standards typically require wide streets that encourage high-speed trafficand sometimes do not require sidewalks.

3. It is not easy to use public transportation in suburban locations.

4. Barriers to walking are created unintentionally.

Consequently, suburban activities essentially require the use of a car and generate largeamounts of vehicular traffic.

Pedestrian travel is often an afterthought in the development process. The results areimpassable barriers to walking both within and between developments. For example, earlysuburban communities had no sidewalks. Later, some communities required developers toinstall sidewalks. Consequently, in most suburbs there is a patchwork of sidewalks that startand stop but often are not linked.

Suburban neighborhood design can be modified to encourage walking. A pedestrian-oriented neighborhood should include the following characteristics:

Streets that are laid out in well-connected patterns on a pedestrian scale so that there arealternative automobile and pedestrian routes to every destination.

A well-designed street environment that encourages intermodal transportation. Thesestreets should include pedestrian scale lighting, trees, sidewalks, and buildings that arewithin close walking distance to the sidewalk.

Residential and internal commercial streets that are relatively narrow to discourage high-speed automobile traffic.

On-street parallel parking is recommended where it can be used as a buffer between pe-destrians and motor vehicle traffic. Parked cars also serve to slow down passing traffic.

Building uses that are often interspersed, i.e., small homes, large homes, outbuildings,small apartment buildings, corner stores, restaurants and offices.

In addition to streets, public open spaces, around which are larger shops and offices aswell as apartments.

Local zoning ordinances can be revised to require more attention to the needs of pedes-trians. Some examples are discussed below.

Residential subdivision layout should provide safe, convenient, and direct pedestrian ac-cess to nearby (within one-half mile) and adjacent residential areas, bus stops, and neigh-borhood activity centers such as schools, parks, commercial and industrial areas, and officeparks. Cul-de-sacs have proven to be effective in restricting automobile through traffic. How-ever, they can also have the effect of restricting pedestrian mobility unless public accesswaysare provided to connect the cul-de-sacs with adjacent streets. Trail connections between cul-

de-sacs and adjacent streets (shown in Figure 21.1) should be provided wherever possible



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PEDESTRIANS 21.9

(a)

FIGURE 21.1 Subdivision layouts: (a) Conventional subdivision layout showing lack of pedestrian connec-tivity between streets and other land uses; (b) subdivision layout that provides pedestrian connections (indicatedby the heavy lines) between streets and other land uses.

to improve access for pedestrians. Pedestrian facilities should be designed to meet local andstatewide design standards.

In some high-density residential areas, regulations require off-street parking and reduced

lot frontage. This results in homefronts that consist largely of garage doors. Ordinancesshould be modified to allow for rear-lot access (alleys) or other innovative solutions in theseareas. Parking codes can be modified to allow for a reduced parking option for developmentslocated on bus routes and which provide facilities that encourage biking and walking.

One of the most important factors in a persons decision to walk is the proximity of goodsand services to homes and workplaces. The most conducive land use for pedestrian activityis one with a higher density mix of housing, offices, and retail. Major pedestrian improve-ments will occur as land use changes reduce the distances between daily activities. Suchland-use changes include increasing density and mixing land use. While converting suburbanlocations to accommodate pedestrians is more difficult than downtown, such low-densitydevelopment offers opportunities not possible in built-up neighborhoods. A strategy of (1)linking internal spaces where possible and (2) making the street usable for pedestrians will

enhance suburban living for many people.



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(b)

FIGURE 21.1 (Continued)

Extending and/or improving pedestrian access within a suburban community may elim-inate some need for a car, allowing increased flexibility for those who have to drive. Mostwalkways should be planned in conjunction with roads so pedestrians can reach all devel-opments that are located along the road.

Sidewalk width should vary to adjust to physical conditions and pedestrian volumes.

Sidewalks near stores and schools should be wider to accommodate more people. Wherethere is a view, the sidewalk should be widened and a bench and landscaping added. Lo-cations of commuter bus stops should be noted. Opportunities for short-cuts that make accesseasier should be identified. The success of suburban transit depends partly on the adequacyof the sidewalks and ease with which people can walk to bus stops.

Entrances to many commercial and retail centers are oriented toward automobile travel.Pedestrian access to storefronts is not only difficult and awkward, but often unsafe. A typicalshopping center or strip mall is separated from the roadway by a wide parking lot. Thereare often no pathways linking store entrances to the sidewalks along the street, and in factthere may be no sidewalks along the street to be linked. Parking lots with multiple accesspoints allow traffic circulation in different directions, creating hazards and confusion forwalkers. Figure 21.2 illustrates a location that is not pedestrian friendly.



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PEDESTRIANS 21.11

FIGURE 21.2 Lack of pedestrian connections to and within a retail center.

Such locations can be redeveloped to serve pedestrians better. As older commercial/retaillocations undergo renovations, they should be redesigned to serve customers who arrive viaautomobile, transit, and bicycle and on foot. Specific methods include:

Maximize pedestrian and transit access to the site from adjacent land uses.

Provide comfortable transit stops and shelters with pedestrian connections to the mainbuildings.

Locate transit stops and pedestrian drop-offs with reasonable proximity to building en-trances.

Provide attractive pedestrian walkways between the stores and the adjacent sites.

Ensure that fencing and landscaping do not create barriers to pedestrian mobility.

Rework entrances and orient buildings toward pedestrians and transit facilities instead ofparking lots.

Connect all buildings on site to each other via attractive pedestrian walkways, with land-scaping and pedestrian-scale lighting. Provide covered walkways between buildings if pos-sible.

Minimize pedestrian-automobile conflicts by consolidating auto entrances into parking lots.

While many transit agencies in the United States have expended significant planning anddesign efforts to meet the needs of pedestrians in transit stations, relatively little attentionhas been devoted to the pedestrian environment to and from the stations. This hinders con-sideration of the door-to-door experience of using public transportation. It is not unusual forseveral different entities to maintain independent control over the various facilities that areused by someone walking to/from a single transit stop. State and local governments withresponsibility for constructing and maintaining pedestrian facilities should cooperate with



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transit agencies, the private sector, and interested citizens in developing action programs toreduce barriers to pedestrian access to transit.

When given sidewalks and traffic-calmed streets to walk along, safe and convenient waysto cross streets, and a comfortable and attractive environment, most people are willing towalk farther to reach public transportation. Unfortunately, matters beyond the boundaries of

the transit station have typically not received much attention in the United States. For ex-ample, park-and-ride lots are often located near freeways and/or shopping areas where res-idential housing is quite far away and there are no paths or sidewalks nearby.

However, the experience of some transit agencies shows there is growing awareness ofthe need to look at the larger environment that surrounds and leads to transit stations andbus stops. Examples of enhancing pedestrian access include placing pedestrian signals anddetectors at key intersections, wider sidewalks, pedestrian shortcuts to key destinations, andtrees.

21.3.3 Pedestrian Level of Service

The Highway Capacity Manual (TRB 2000) suggests that the quality of a pedestrians ex-perience is similar to an automobile-based measure, i.e., vehicles that are moving at slowspeed or stopped due to congestion have low levels of service. They acknowledge thatenvironmental factors also influence pedestrian activity. While speed, space, and delay areone set of measures of quality, there are other indicators of a good walking environment.Burden (1999) indicates that high pedestrian densities may indicate success. He notes thatthere are a number of attractions throughout the world where large crowds give excitementand security to a place.

Unlike high-speed motorists, whose travel is facilitated when the environment lacks detail,pedestrian travel is slow and interactive with the block, street, or neighborhood. The slowerpace requires attention to detail. In fact, as Berkovitz (2001) points out, pedestrians are oftenintimidated by empty sidewalks and long travel distances, particularly along high-speed

roads.Landis et al. (2002) point out that evaluating the performance of a roadway section forwalking is much more complex in comparison to that of the motor vehicle mode. Whilemotor vehicle operators are largely insulated in their travel environment and are influencedby relatively few factors, pedestrians are relatively unprotected and are subject to a varietyof environmental conditions. They note that there is not yet consensus among planners andengineers on which features of a roadway environment have statistically reliable significanceto pedestrians. Several walkability audits have been developed that include a large numberof features of the entire roadway corridor environment. Landis et al. (2002) present a list offactors on which it is generally agreed that pedestrians sense of comfort and safety withina roadway corridor is based. These include: personal safety (i.e., threat of crashes), personalsecurity (i.e., threat of assault), architectural interest, pathway or sidewalk shade, pedestrian-

scale lighting and amenities, presence of other pedestrians, and conditions at intersections.

21.4 PEDESTRIAN SAFETY

The engineering literature on pedestrian safety tends to focus on pedestrian crash types, i.e.,incidents where a pedestrian comes into contact with a motor vehicle. This is logical sincemany of these crashes are reported through the uniform crash reporting systems in eachstate. However, reliance on such data significantly understates the magnitude of the pedes-trian safety problem since it typically ignores crashes that occur on private property such asparking lots or driveways. More importantly, incidents where pedestrians slip, trip, or fall

on a sidewalk, stair, ramp, or other facility are not included. As described below, availabledata suggest that these non-motor-vehicle-involved incidents occur more frequently than



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PEDESTRIANS 21.13

motor-vehicle-involved crashes. This section examines both types of incidents by discussingcommon crash types and/or injury mechanisms. Tort liability issues are outlined along withrisk management strategies for enhancing pedestrian safety.

21.4.1 Pedestrian Crash Types

According to Federal Highway Administration (FHWA) data, approximately 6,500 pedestri-ans are killed each year as a result of collisions with motor vehicles. In some large urbanareas, pedestrians account for as much as 40 to 50 percent of traffic fatalities. Many moreinjuries are probably not reported to record-keeping agencies.

A FHWA study (Hunter, Stutts, and Pein, 1997) found that compared to their represen-tation in the overall U.S. population, young persons (under 25 years of age) were over-represented in pedestrian-motor vehicle crashes. Older adults (ages 25 to 44) and the elderly(age 65) were underrepresented. However, elderly pedestrians in crashes were more thantwice as likely to be killed (15 percent versus 6 percent) compared to young persons.

In general, pedestrian crashes occurred most frequently during the late afternoon and early

evening hours. These are times when exposure is probably highest and visibility may be aproblem. Alcohol or drug use was noted in about 15 percent of the pedestrian crashes overall.This increased to 31 percent for pedestrians in the 2544 age group. Alcohol/drug crasheswere also more frequent on weekends and during hours of darkness.

Forty-one percent of crashes occurred at roadway intersections, and an additional 8 per-cent occurred in driveways or alley intersections. About two-thirds of crashes were catego-rized as urban. Fifteen percent of the pedestrian crashes reported occurred on private property,primarily in commercial or other parking lots. The elderly were overrepresented in com-mercial parking lot crashes, young adults in non-commercial parking lot crashes, and childrenunder age 10 in collisions involving driveways, alleys, or yards.

The eight most common pedestrian crash types identified by Hunter, Stutts and Pein(1997) are outlined below:

Vehicle turn/merge: Pedestrian and vehicle collided while the vehicle was preparing toturn, in the process of turning, or had just completed a turn or merge.

Mid-block dash: At a mid-block location, the pedestrian was struck while running and themotorists view of the pedestrian was not obstructed.

Not in roadway: The pedestrian was struck when not in the roadway. Areas includedparking lots, driveways, private roads, sidewalks, service stations, and yards.

Walking along roadway: Pedestrian was struck while walking (or running) along a roadwithout sidewalks. The pedestrian may have been hitchhiking, walking with traffic andstruck from behind or from the front, walking against traffic and struck from behind orfrom the front, or walking along a road but the details are unknown.

Intersection dash: Pedestrian was struck while running through an intersection and/or themotorists view of the pedestrian was blocked until an instant before impact.

Intersectionother: Crash occurred at an intersection but does not conform to any of thespecified crash types.

Backing vehiclePedestrian was struck by a vehicle that was backing.

Mid-blockother: The crash occurred at mid-block but does not conform to any of thespecified crash types.

21.4.2 Non-Motor-Vehicle-Involved Incidents

The number of same-level falls is unknown. As Hyde et al. (2002) point out, falls thatdo not cause injury are not recorded. Therefore, researchers are limited to studying the



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incidence of such falls as reported by hospitals and similar institutions. Even with a signif-icant number of injury and non-injury incidents going unreported, clearly the magnitude ofthe fall problem is significant. Data show that falls are the leading cause of injury reportedto an emergency room. According to The Injury Fact Book (Baker et al. 1992), accidentalfalls are the second-leading cause of unintentional death, the second-leading cause of both

spinal cord and brain injury, and the most common cause of hospital admission for trauma.While data exist on reported falls, i.e., the more serious falls, there is not good informationabout the circumstances surrounding the fall, i.e., did the individual slip on ice, trip on araised section of sidewalk or fall on a stairway? In this regard, the author (Eck and Simpson1996) attempted to use hospital records to obtain detailed information about falls to assistin countermeasure development. Results pointed out the importance of surface conditions topedestrian safety. Two general types of surface condition problems were identified: slipperysurfaces due to accumulation of ice and snow and holes or openings in the surface itself,e.g., missing, ill-fitting, or defective grates. While the former problem is one of maintenance,the latter issue has facility design, construction, and maintenance implications.

21.4.3 Tort Liability

As discussed above, planners and roadway designers and engineers must consider the needsof the pedestrian. Design, construction, maintenance, and operation of roads and streets,bridges, and surface condition must recognize the pedestrian. Roadway and recreationalfacilities that fail to incorporate the needs of all users increase the likelihood of claims againstfacility owners/managers.

Liability is an increasingly important issue for both public agencies and private entities.Implementing an aggressive and well-publicized risk management program can help headoff these problems. It is useful to look at some of the design, construction, maintenance,and operational problems that commonly are cited in claims or lawsuits involving pedestri-ans.

Open drainage grates in travel way

Inadequate utility box covers (raised/depressed, poor skid resistance, or structural prob-lems)

Paths that suddenly end at bad locations with no transition or escape route provided

Long-term, severe surface irregularities (e.g., broken pavement, potholes)

Foreign substances on travel surface (e.g., water, sealants, oil/ grease, loose stones orgravel)

Vertical elevation differences in walkways

Bridges that are hazardous to pedestrians

Design errors, e.g., at curb ramps Wheelstops in parking lots

Lack of railings between path and adjacent slope (and conditions at bottom)

Figure 21.3 shows wheelstops intruding into a walkway, creating a tripping hazard for pe-destrians.

21.4.4 Risk Management Strategies

Outlined below are elements of an effective risk management strategy. Conscientiously im-plementing these elements should result in safer pedestrian facilities with fewer injuries, and

therefore fewer claims, and should increase the likelihood of a successful defense for thoseclaims that proceed to trial.



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PEDESTRIANS 21.15

FIGURE 21.3 Wheelstops from parking lot intruding onto and near sidewalk, creating trippinghazard for pedestrians.

Perhaps the overarching strategy is to follow common sense principles for a defensibleprogram. This means providing immediate response to the risks identified, including signingand warning for those conditions that cannot be immediately changed and funding spotimprovements for those that can be changed. Listen to the public. If a parent calls, an editorialis written, or any other input from a customer suggests action, the situation should beevaluated and action taken as quickly and as intelligently as possible. All agencies, depart-ments, and other parties whose duties are affected need to be involved. The risk-reductioneffort takes cooperation and ongoing coordination.

Other specific actions that can be taken include:

Incorporate accepted standards and guidelines.

Use established engineering, planning, and design principles.

Consider all potential users.

Do it right!

Promote community involvement and awareness.

21.5 PEDESTRIAN FACILITY DESIGN

21.5.1 Walkways, Sidewalks, and Public Spaces

A successful urban sidewalk should have the following characteristics:

Adequate width

Buffer from travel lane

Gentle cross-slope (2 percent or less)



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FIGURE 21.4 Corner bulb-out on arterial street.

Buffer to private properties

Adequate sight distances around corners and at driveways

Shy distances to walls and other structures

Continuity

Clear path of travel free of street furniture Well-maintained condition

Ramps at corners and flat areas across driveways

Sufficient storage capacity at corners

Sidewalks require a minimum width of 5 feet if set back from the curb or 6 feet if at thecurb face. Walking is a social activity. For two people to walk together, 5 feet of space isthe bare minimum needed. In some areas, such as near schools, sporting complexes, someparks, and many shopping districts, the minimum width for a sidewalk is 8 feet.

The desirable width for a sidewalk is often much greater. Some shopping districts require12, 20, 30, or even 40 feet of width to handle the volume of pedestrian traffic they encounter.

Pennsylvania Avenue in Washington, DC, has 30-foot sidewalk sections to handle tour busoperations. The Highway Capacity Manual (TRB 2000) covers the topics of sidewalk widthand pedestrian level of service.

It is important to determine the commercial need for outdoor cafes, kiosks, corner gath-ering spots, and other social needs for a sidewalk. In commercial areas, designers shouldconsult property owners, chambers of commerce, downtown merchants associations, andlandscape architects to ascertain if the desired width is realistic. Corner or mid-block bulb-outs can be used to advantage for creating both storage space and for roadway crossing andsocial space. Figure 21.4 shows a corner bulb-out on an arterial street.

Most sidewalks are made of concrete due to its long life, distinct pattern, and lightercolor. In some cases, asphalt can provide a useful surface.



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PEDESTRIANS 21.17

Paver stones can also be used. These colorful brick, stone, or ceramic tiles are often usedto define corners or crosswalks (as illustrated in Figure 21.4), to create a mood for a blockor commercial district, or to help those with visual impairments. The blocks need to be seton a concrete pad for maximum life and stability.

Certain cautions are in order relative to paver stones, bricks, and similar materials. The

FHWA publication (2001) on best practices in designing trails for access points out thatdecorative surfaces may create a vibrating, bumpy ride that can be uncomfortable and painfulfor those in wheelchairs. Pavers or bricks can settle or buckle, creating changes in level.This creates a tripping hazard for people with vision impairments and for ambulatory pe-destrians with visibility impairments. Finally, decorative surface materials can make it moredifficult for pedestrians with vision impairments to identify detectable warnings that providecritical information about the transition from sidewalk to the street. For these reasons, paver,brick, or cobblestone sidewalks are not recommended. Concrete sidewalks with paver orbrick trim preserve the decorative qualities but present an easier surface to negotiate.

Desirably, a border area should be provided along streets for the safety of motorists andpedestrians as well as for aesthetic reasons. The border area between the roadway and theright-of-way line should be wide enough to serve multiple purposes, including provision of

buffer space between pedestrians and vehicular traffic, snow storage, an area for placementof underground utilities, and an area for maintainable landscaping. The border may be aminimum of 5 feet but desirably it should be 10 feet.

Nature strips, particularly in downtown areas, are a good location to use paver stones foreasy and affordable access to underground utilities. In downtown areas, nature strips are alsoa convenient location for the swing width of a door and for placement of parking meters,hydrants, lampposts, and other furniture.

On-street parking has two distinct advantages for pedestrians. First, it creates desiredphysical separation from motor vehicle traffic. Second, it has been shown to reduce motoristtravel speeds, thus creating a safer environment for street crossings.

On the back side of sidewalks, a minimum width buffer of 1 to 3 feet is essential. Withoutsuch a buffer, vegetation, walls, buildings, and other objects encroach on the usable sidewalk

space.Pedestrians require a shy distance from fixed objects, such as walls, fences, shrubs, build-ings, parked cars, and other features. The desired shy distance for a pedestrian is 2 feet.Allowance for this shy distance must be made in determining the functional width of asidewalk.

The literature points out that attractive windows in shopping districts cause curious pe-destrians to stop momentarily. This is a desired element of a successful street. These window-watchers take up about 18 to 24 inches of space.

Because of its relatively slow pace, walking is more detail-oriented than driving. Walkersare attracted to locations with amenities, interesting storefronts, and outdoor cafes. On theother hand, pedestrians will avoid sidewalks lined with walls or that lack interesting details.Compare Figure 21.5, with its amenities and interesting details, with the wall effect shown

in Figure 21.6. Where would you rather walk?Newspaper racks, mailboxes, and other street furniture should not encroach into walkingspace. The items can be placed in a nature strip, a separate storage area behind the sidewalk,or in a corner or mid-block bulb-out. These items should be bolted in place.

AASHTOs highway design policy (2001) states that landscaping should be provided foraesthetic and erosion-control purposes in keeping with the character of the street and itsenvironment. Landscaping should be arranged to permit sufficiently wide, clear, and safepedestrian walkways. Combinations of turf, shrubs, and trees are desirable in border areasalong roadways. However, care must be taken to ensure that sight distances and clearancesto obstructions are preserved, particularly at intersections.

Landscaping can also be used to control, partially or fully, crossing points of pedestrians.Low shrubs in commercial areas and near schools are often desirable to channel pedestrians

to crosswalks or crossing areas.



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FIGURE 21.5 Sidewalk cafe and other amenities create an inviting sidewalk.

FIGURE 21.6 Empty wall (due to drawn blinds) and lack of amenities do not attract pedestrians.



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PEDESTRIANS 21.19

Management of corner space is critical to the success of a commercial street. This smallpublic space enhances the corner sight triangle, permits underground piping of drainage sothat street water can be captured on both sides of the crossing, provides a resting place,stores pedestrians waiting to cross the roadway, and offers a location for pedestrian amenities.Well-designed corners, particularly in a downtown or village-like shopping district, can be-

come a focal point for an area. Benches, telephones, newspaper racks, mailboxes, bike racks,and other features help to enliven this area. Corners are often the most secure places on astreet.

Parking structures in commercial districts should ideally be placed away from popularwalking streets. If this is not possible, driveway and curb radii should be kept tight tomaximize safety and to minimize discomfort to pedestrians.

If possible, grades should be kept to no more than 5 percent; terrain permitting, gradessteeper than 8 percent should be avoided. Where this is not possible, railings and other aidsshould be considered to assist older adults. The Americans with Disabilities Act (ADA) doesnot require designers to change topography but only to work within its limitations andconstraints. Do not create a constructed grade that exceeds 8 percent.

Stairs should be avoided where possible since they are a barrier to accessibility and falls

are common on poorly designed stairs. It is critical that stairs be well-constructed and main-tained, easily detectable, and slip-resistant. The following principles apply; consult localbuilding codes for additional details. Minimum stairway width is 42 inches, to allow twopeople to pass. Stairs require railings on at least one side. Railings must extend 18 inchesbeyond the top and bottom stair. For wide stairs, such as might be present at passengertransportation terminals, there should be railings on both sides and one or more in mid-stairareas. Open risers should be avoided. The stair should have a uniform grade with constanttread and rise along the stair. For exterior stairs, the tread should have a forward slope of 1percent to drain water. Stairs should be illuminated at night.

Sidewalks are recommended on both sides of all urban arterials, collectors and on mostlocal roadways. Codes should require sidewalks for new construction. Lack of sidewalks ona road or street means conflicts with vehicles are maximized. Children, older adults, and

people with disabilities may not have mobility under these circumstances. When prioritizingmissing sidewalks, the following factors should be considered: schools, transit stops, parks,shopping districts and commercial areas, medical complexes and hospitals, retirement homes,and public buildings

Experience has shown that the features summarized below are desirable to achieve robustcommercial activity and to encourage added walking versus single-occupant motor vehicletrips. Suchers excellent book (1995) on city comforts is recommended for more detailedinformation.

Trees. FHWA text (n.d.) states that the most charming streets are those with trees gracingboth sides of a walkway. The canopy effect is attractive to pedestrians. Trees should be setback 4 feet from the curb.

Awnings. Retail shops should be encouraged to provide protective awnings to create shade,provide protection from rain and snow, and add color and attractiveness to the street. Awningsare especially important in warm climates on the sunny side of the street.

Outdoor Cafes. Careful regulation of street vendors, outdoor cafes, and other commercialactivity help enliven a placethe more activity, the better. One successful outdoor cafe helpscreate more activity, and in time an entire area can be helped back to life. When outdoorcafes are present, it is essential to maintain a reasonable walking passageway. Eliminationof two or three parking spaces in the street and addition of a bulb-out area can often providethe necessary extra space when cafe seating is needed.



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Alleys and Narrow Streets. Alleys can be cleaned up and made attractive for walking.Properly planned and lit, they can be secure and inviting. Some communities have coveredover alleys and made them into access points for a number of shops. Alleys can becomeattractive places for outdoor cafes, kiosks, and small shops.

Gateways. Gateways identify a place by defining boundaries. They create a sense of wel-come and transition.

Kiosks. Small tourist centers, navigational kiosks, and attractive outlets for other infor-mation can be handled through small-scale or large-scale kiosks. Well-located interpretivekiosks, plaques, and other instructional or historic place markers are essential to visitors.These areas can also serve as safe places for people to meet and can generally help withnavigation.

Fountains, Play Areas, and Public Art. Public play areas and interactive art can enlivena corner or central plaza. Project for Public Spaces, Inc. (2001) points out that for suchamenities to work, they must respond to the needs of a location, to the activities that take

place there, and to peoples pattern of use.

Pedestrian Streets, Transit Streets, and Pedestrian Malls. Many cities throughout theworld have successfully converted streets to transit and pedestrian streets. These conversionsneed to be made with a master plan so that traffic flow and pedestrian movements areprovided for fully.

21.5.2 Pedestrian Plazas

Pedestrian plazas are defined as places of abundant vegetation, artwork, seating, and perhapsfountains, which are intended not only as quiet spots for rest and contemplation but as centers

where communities can come together to socialize and take part in a variety of activities(Project for Public Spaces, Inc. 2001). Unfortunately, many recently constructed plazas servemore to enhance the image of the building on the lot in that they are too large and uncom-fortable for pedestrians. Problems with plazas include:

Some are windswept.

Some are on the shady side of buildings.

Some break the continuity of shopping streets.

Some are inaccessible because of grade changes.

Most are without benches, planters, cover, shops, or other pedestrian comforts.

To be comfortable, large spaces should be divided into smaller ones. Landscaping, benches,and wind and rain protection should be provided, and shopping and eating should be madeaccessible. Encourage the use of bandstands, public display areas, outdoor dining space,skating rinks, and other features that attract crowds.

FHWA (n.d.) indicates that no extra room should be provided. It is usually better to bea bit crowded than too open and to provide many smaller spaces instead of a few large ones.It is better to have places to sit, planters, and other conveniences for pedestrians than to haveclean, simple, and architectural space. It is better to have windows for browsing and storesadjacent to the plaza space, with cross-circulation between different uses, than to have theplaza serve one use. It is better to have retailers rather than offices border the plaza. It isbetter for the plaza to be part of the sidewalk instead of separated from the sidewalk bywalls. The popular downtown plaza in Montreal, shown in Figure 21.7, has most of these

attributes.



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PEDESTRIANS 21.21

FIGURE 21.7 Popular plaza in downtown Montreal.

Ideally, plazas should be located to provide good sun exposure and little wind exposurein places that are protected from traffic noise and in areas that are easily accessible fromstreets and shops. Planners should inventory the area for spaces that can be used for plazas,

especially small ones. Appropriate spaces include locations where buildings may be demol-ished and new ones constructed, vacant land, or streets that may be closed to traffic or mayconnect to parking. The Project for Public Spaces, Inc. (2002) handbook on creating suc-cessful public spaces is an excellent resource on this topic.

21.5.3 Intersections

Intersections are locations where the paths of vehicles and pedestrians come together. Theycan be the most challenging part of negotiating the pedestrian network. If pedestrians cannotcross the street safely, then mobility is severely limited, access is denied, and walking as amode of travel is discouraged. In designing and operating intersections that are attentive to

the needs of pedestrians, the following considerations should be addressed:

Enhancing visibility of pedestrians through painted crosswalks, moving pedestrians outfrom behind parked vehicles by using bulb-outs, and increasing sight distances by remov-ing obstructions such as vegetation and street furniture

Minimizing time and distance pedestrians need to cross roadway

Making pedestrian movements more predictable through the use of crosswalks and sig-nalization

Using curb ramps to provide transition from walkway to street

The following features of intersections should be designed from the pedestrian as well as

motor vehicle standpoint:



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Crosswalks. One way to shorten the crossing distance for pedestrians on streets whereparking is permitted is to install curb bulbs or curb extensions. As shown in Figure 21.4,curb bulbs project into the street usually for a distance equal to the depth of a typical parallelparking space, thereby making it easier for pedestrians to see approaching traffic and givingmotorists a better view of pedestrians. When designing curb bulbs at intersections where

there is low truck traffic, the corner radius should be as small as possible to have the effectof slowing down right-turning traffic.

Signal Timing, Indications, and Detection. Pedestrians are often confused by pedestrianphase signal timing and pushbuttons since these seem to vary not only from place to placebut also from intersection to intersection. The timing of WALK and DONT WALK phasesappears arbitrary. Many pedestrians do not know that the flashing DONT WALK is inten-tionally displayed before the average pedestrian can get completely across the street. Or thesignal timing may be too fast for slow walkers such as older pedestrians or people withdisabilities. FHWA (n.d.) recommends that agencies develop policies regarding pedestriansignal timing and pushbutton actuation to ensure fair treatment for pedestrians. Signal timingshould be calculated based on a walking speed of 2.8 feet per second, as opposed to the

average walking speed of 4 feet per second. This will accommodate older pedestrians andthose with mobility impairments. The pushbutton should be placed at the top of and as nearas possible to the curb ramp and clearly in line with the direction of travel. This is especiallyimportant for pedestrians with low vision. The pushbutton box should provide a visibleacknowledgment that the crossing request has been received.

Refuge Islands. Pedestrian refuge islands are the areas within an intersection or betweenlanes of travel where pedestrians may safely wait until vehicular traffic clears, allowing themto cross a street. Such islands are commonly found on wide, multilane streets where adequatepedestrian crossing times cannot be provided without adversely affecting traffic flow. Theyalso provide a resting place for those pedestrians (elderly, wheelchair-bound, or others) un-able to cross the intersection completely within the allotted time. Pedestrian refuge islands

may be installed at intersections or mid-block locations as determined by engineering studies.They must be designed in accordance with the AASHTO design policy (2001) and MUTCD(FHWA 2000) requirements. Raised curb islands need cut-through ramps at pavement levelor curb ramps for wheelchair users. The island should be at least 6 feet wide from face ofcurb to face of curb (minimum width shall not be less than 4 feet). The island should notbe less than 12 feet long or the width of the crosswalk, whichever is greater. Minimum islandsize should be 50 square feet. There should be no obstructions to visibility, e.g., barriers,vegetation, or benches.

21.5.4 Mid-Block Crossings

Designers often assume that pedestrians will cross roadways at established intersections.However, pedestrians routinely cross the street at mid-block locations. Pedestrians will rarelygo out of their way to cross at an intersection unless they are rewarded with a much-improvedcrossing. As noted earlier, pedestrians will take the most direct route, even it means crossingseveral lanes of high-speed traffic. Pedestrians crossing at random and unpredictable locationscreate confusion and increase risks to both the pedestrians and drivers. Well-designed andproperly located mid-block crossings can actually provide safety benefits for pedestrians.Two primary ways to facilitate non-intersection crossings are medians and mid-block cross-ings. Figure 21.8 shows a mid-block crossing which incorporates a median and traffic calm-ing elements. The crossing connects a parking structure with a retail mall.

A median or refuge island is a raised longitudinal space separating opposing traffic di-rections. A pedestrian faced with crossing one or more lanes in each direction must determine

a safe gap in two, four, or six lanes at a timea complex task. Younger and older drivershave reduced gap-acceptance skills compared to pedestrians in other age groups. Pedestrian



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PEDESTRIANS 21.23

FIGURE 21.8 Mid-block crossing connecting parking structure with downtown retail mall.

gap-assessment skills are particularly poor at night. A median allows pedestrians to separatethe crossing into two tasks, negotiating one direction of traffic at a time. Crossing times arereduced, making the walk across the street much safer.

Desirably, a median should be at least 8 feet wide to allow a pedestrian to wait com-fortably in the center, 4 feet from moving traffic. Normally there will be an open flat cutrather than a ramp, due to the short width.

Mid-block crossings are located and placed according to a number of factors, includingroadway width, traffic volume, traffic speed and type, desire lines for pedestrian movement,and adjacent land use. Due to their low speed and volume, local roads generally do not havemedian treatments. However, there may be exceptions, particularly around schools or hos-pitals where traffic calming is desired.

The design of mid-block crossings uses warrants similar to those used for conventionalintersections, e.g., stopping sight distance, effects of grade, need for lighting, and otherfactors. The designer should recognize that pedestrians have a strong desire to continue theirintended path of travel. Natural patterns should be identified. For example, a parking lot onone side of the street connecting a large office complex or shopping center on anotherestablishes the desired crossing location. Grade-separated mid-block crossings have beeneffective in a few isolated locations. Due to their cost and potentially low use, engineeringstudies should be conducted. Given a choice, on most roadways pedestrians generally preferto cross at grade.

21.5.5 Accessibility

According to the FHWA publication (1999) on designing facilities for access, there are 49million people in the United States with disabilities. At one time or another, virtually all of

them are pedestrians. Anyone can experience a temporary or permanent disability at anytime due to age, illness, or injury. It is estimated that 85 percent of Americans living to their



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full life expectancy will suffer a permanent disability. Good design is important so that theseindividuals are not restricted in their mobility.

The Americans with Disabilities Act (ADA) was enacted in 1990 to ensure that a disabledperson has access to all public facilities in the United States. The law has specific require-ments for pedestrian facilities on public and private property. This section provides an over-

view of basic accessibility requirements that are relevant to designing pedestrian facilities.The complete set of standards can be found in the Americans with Disabilities Act Acces-sibility Guidelines (ADAAG) developed by the Access Board. Note that the rules are updatedfrom time to time.

Sidewalks. Wheelchairs require a 3-foot minimum width for continuous passage. Therefore,sidewalks should have a minimum clearance width of 5 feet. Sidewalks should be surfacedwith a smooth, durable, and slip-resistant material. They should be kept in good condition,free from debris, cracks, and rough surfaces. Sidewalks should have the minimum cross-slope necessary for proper drainage. The maximum cross-slope is 2 percent (1:50). A personusing crutches or a wheelchair has to exert significantly more effort to maintain a straightcourse on a sloped surface than on a level surface. Driveway slopes should not encroach on

the sidewalk.

Ramps. Ramps are locations where the grade exceeds 5 percent along an accessible path.Longitudinal grades on sidewalks should be limited to 5 percent but may be a maximum of1:12 if necessary. Long, steep grades should have level areas every 30 feet since traversinga steep slope with crutches or artificial limbs or in a wheelchair is difficult and level areasare needed for the pedestrian to stop and rest.

Street Furniture. Street furniture includes things such as benches, newspaper boxes, trashreceptacles, and bus shelters. To accommodate the disabled, street furniture should be out ofthe normal travel path as much as possible. For greater conspicuity, high-contrast colors suchas red, yellow, and black are preferable. Guidelines for street furniture include the following:

No protruding object should reduce the clear width of a sidewalk or walkway path to lessthan 3 feet.

No object mounted on a wall or post or freestanding should have a clear open area underit higher than 2.3 feet off the ground.

No object higher than 2.3 feet attached to a wall should protrude from that wall more than4 inches.

Pedestrian Signals. Some individuals have difficulty operating conventional pedestrianpushbuttons. There may be a need to install a larger pushbutton or to change the placementof the pushbutton. Pedestrian pushbuttons should always be easily accessible to individualsin wheelchairs and should be no more than 42 inches above the sidewalk. The force required

to activate the button should be no greater than 5 pounds.Accessible pedestrian signals provide audible and/or vibrotactile information coinciding

with visual pedestrian signals to let blind or low-vision pedestrians know precisely when theWALK interval begins. Bentzen (1998) identifies intersections that may require evaluationfor accessible pedestrian signal installation. These include very wide crossings, secondarystreets having little traffic, nonorthogonal or skewed crossings, T-intersections, high volumesof turning vehicles, split-phase signal timing, and noisy locations. Where these conditionsoccur, it may be impossible for a pedestrian who is blind to determine the onset of paralleltraffic or to obtain usable orientation and directional information about the crossing fromthe cues that are available.

Curb Cut Ramps. The single most important design consideration for persons in wheel-

chairs is to provide curb cuts. New and rebuilt streets with sidewalks should have curb cuts



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PEDESTRIANS 21.25

FIGURE 21.9 Multiuse riverfront trail in Reno, Nevada.

at all crosswalks. It is desirable to provide two curb cuts per corner (single ramps locatedin the center of a corner are less desirable). Separate ramps provide greater information tovisually impaired pedestrians in street crossings, especially if the ramp is designed to beparallel to the crosswalk. These also benefit others with mobility limitations, elderly pedes-trians, and persons pushing strollers or carts.

ADAAG specifies that curb ramps should be at least 36 inches wide, not including thewidth of the flared sides. According to ADAAG, the slope of a curb ramp should not exceed8.33 percent; the cross-slope should not exceed 2 percent. If the landing (level area ofsidewalk at the top of a curb ramp) width is less than 48 inches, then the slope of the flaresat the curb face should not exceed 8.33 percent. If the landing width is greater than 48inches, a 10 percent slope is acceptable.

Ramps should be checked periodically to make sure large gaps do not develop betweenthe gutter and street surface. Drainage is very important with curb cuts. Standing water canobscure a drop-off or pothole at the base of a ramp and makes the crossing messy. Stormdrain inlets should be clear of the crosswalk.

21.5.6 Multiuse Trails

Multiuse or off-road trails provide environments for walking and other non-motorized usersthat, as shown in Figure 21.9, are separate from motor vehicle traffic. Such trails are oftenextremely popular facilities that are in high demand among in-line skaters, bicyclists, joggers,people walking dogs, and a variety of other users. These different trail users have differentobjectives. The resulting mix of objectives and volume of non-motorized traffic can createproblems that should be anticipated during design by understanding the needs of these usersand accommodating expected levels and types of use.

There are many types of trails, including:



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FIGURE 21.10 Separate pathways for pedestrians and bicycles.

Urban trails and pathways

Rail trails

Trails in greenways

Interpretive trails

Historical/heritage trails Primitive trails

All of these can be designed for use by pedestrians (including joggers, casual strollers,hikers, in-line skaters, and others), people with disabilities, and bicyclists. What distinguishesone type of trail from another is its context.

The National Highway Institute (NHI) workbook (1996) cautions that design alone cannotgenerally restrict use. For example, if bicycles are to be prohibited on a path, education andenforcement programs should be implemented to back up the prohibition. Design can pas-sively discourage certain users from traveling on a given trail but only to a limited extent.For example, road bicyclists are not likely to ride on an unpaved surface.

It may be easier to separate types of trail users. Several different separation techniques

are available, including:

Parallel pathwaysone for wheels and one for heels (as shown in Figure 21.10)

Striped lanespedestrians and bikes in separate lanes

Directional separationtraffic in one direction stays to the right; traffic in the other direc-tion stays to the left

Signing and enforcement, e.g., EQUESTRIAN USE ONLY

National guidelines for the design of multiuse trails are provide by AASHTOs (1999)Guide for the Development of Bicycle Facilities. There are a number of other excellent guides



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PEDESTRIANS 21.27

FIGURE 21.11 Multiuse trail in steep terrain.

as well, covering a variety of trail types (e.g., Steinholtz and Vachowski 2001). Schwarz(1993) presents a thorough discussion of greenway trail design including types of trail lay-outs. Figure 21.11 shows a stone-surface multiuse trail in steep terrain that incorporates atimber safety railing.

The minimum width for two-directional trails is 10 feet, although 12- to 14-foot widths

are preferred where heavy traffic is expected. Centerline stripes should be considered forpaths that generate substantial amounts of pedestrian traffic. Appropriate speed limit andwarning signs should be posted. Trail etiquette signs should clearly state that bicycles shouldgive an audible warning before passing other trail users.

The surfacing material on a trail significantly affects which user groups will be capableof negotiating the path. Soft surfaces such as sand and gravel are more difficult for all usersto negotiate. They present special difficulties for those using wheeled devices such as roadbicycles, strollers, and wheelchairs.

The FHWA guide to access (1999) notes that local conditions determine the choice oftrail surface. Recreational trail surfaces are often composed of naturally occurring soil. Sur-faces ranging from concrete to wood chips may be used depending on the designated usertypes, the expected volume of traffic, the climate, and the surrounding environment.

Trail/roadway intersections can become areas of conflict if not carefully designed. Forat-grade intersections, the following characteristics should be included:

1. Position the crossing at a logical and visible location.

2. Warn motorists of the approaching crossing. Warning signs and pavement markings usedto alert motorists of trail crossings should be used in accordance with the MUTCD(FHWA 2000).

3. Maintain visibility between trail users and motorists. Vegetation, signs, and other objectsin the right-of-way should be removed or relocated so that trail users can observe trafficconditions and motorists can see approaching trail users.



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4. Inform trail users of the upcoming intersection. Signs and pavement markings on the trailcan provide advance warning of the intersection, especially in areas where the intersectionis not clearly visible.

The need for parking should be anticipated during the trail-planning process. Adequate park-

ing at trailheads is necessary so that trail users do not park on the shoulder of the road nearintersections, blocking sightlines of both motorists and trail users.Unauthorized motor vehicle access is a problem at some trail/roadway intersections. Trail

bollards are the most effective method of restricting motor vehicle traffic. However, caremust be taken in their use because they present an obstacle when located in the travel pathof pedestrians and bicycles.

Bollards should be painted a bright color and permanently reflectorized to maintain theirvisibility. They should be 3 feet tall and can be constructed of a variety of materials. Com-mercial manufacturers offer bollards that can be unlocked and removed to allow emergencyvehicle and maintenance access.

The NHI workbook (1996) points out that trails can be used to provide connectionsbetween transportation modes. Intermodal linkage possibilities include:

1. To shopping, schools, work, and transit

2. Between parking and transit drop-off points

3. To ports, rivers, and scenic areas

4. To ferry or bridge connections

Access to trails is a key consideration. A trailhead is a location where people can accessa trail. The NHI workbook (1996) indicates that a trailhead can be as simple as a trail markerand few parking stalls or a virtual visitors center with vending machines, snack bar, andinteractive trail guide information.

Good trails attract people who need places to park, rest, get trail information, use rest-rooms, dispose of trash, and get a drink of water. These are the basic considerations. Trail-head design should consider:

Easy access from public streets

Provision of adequate parking

Location relative to transit facilities

Potential joint use, e.g., can also serve as picnic area

Rest rooms and trash disposal

Weather protection

Potential for interpretation of areas historic, cultural, and natural features

Location relative to on-site concessions and ancillary facilities such as bike rentals

21.6 OPERATIONS AND MAINTENANCE

21.6.1 Pedestrian Signs and Pavement Markings

Traffic engineers use a wide variety of signs and pavements markings relative to pedestrians.Some are used to alert motorists to pedestrian activity and others to direct pedestrians todefined crossings.

Signing is governed by the MUTCD (FHWA 2000), which provides guidelines for the

design and placement of traffic control devices installed within public rights-of-way. It must



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PEDESTRIANS 21.29

be noted that signs are often ineffective in modifying driver behavior and overuse of signsbreeds disrespect.

Colors for signs and markings should conform to the color schedule recommended bythe MUTCD to promote uniformity and understanding from jurisdiction to jurisdiction. TheMillennium Edition of the MUTCD includes a new color (in addition to standard yellow)

for pedestrian warning signsfluorescent yellow-green. However, the MUTCD cautions thatthe mixing of standard yellow and fluorescent yellow-green backgrounds within a selectedsite area should be avoided.

The discussion below presents an overview of key issues related to traffic control devicesfor pedestrians. The discussion is organized by type of device.

Regulatory Signs. The NO TURN ON RED sign may be used in some situations to fa-cilitate pedestrian movements. Due to conflicting research results, there has been considerablecontroversy regarding pedestrian safety and right-turn-on-red. Use of NO TURN ON REDsigns at intersections should be evaluated on a case-by-case basis using engineering judg-ment. In August 2002, the Institute of Transportation Engineers was considering guidelinesstating that prohibition of turns on red should only be considered after the need has been

fully established and less restrictive methods have been reviewed or tried. Part-time prohi-bitions should be discouraged; however, they are preferable to full-time prohibitions whenthe actual need occurs for only short periods of time. ITE recommends that less restrictivealternatives be considered in lieu of prohibiting all turns on red. A supplemental plate readingWHEN PEDESTRIANS ARE PRESENT may aid the pedestrian without unduly restrictingvehicular traffic flow. Education and enforcement play important roles in the benefits andsafety of right-turn-on-red. Enforcement is important relative to turns being made only afterstopping and yielding to other road users and that the necessary prohibitions are beingobserved.

Other signs include the pedestrian pushbutton signs or other signs at signals directingpedestrians to cross only on the green light or WALK signal. Pedestrian pushbutton signsshould be used at all pedestrian-actuated signals. It is helpful to provide guidance to indicate

which street the button is for. The signs should be located adjacent to the pushbutton andpushbuttons should be accessible to pedestrians with disabilities.Educational plaques may be used for pedestrians at traffic signals to define the meaning

of the WALK, DONT WALK, and flashing DONT WALK signal indications. The decisionto use these signs is strictly engineering judgment and is primarily for educational purposes(to improve pedestrian understanding of pedestrian indications).

Warning Signs. The pedestrian crossing sign (W11-2, as shown in Figure 21.12a) may beused to alert road users to locations where unexpected entries into the roadway by pedestriansmight occur. The crossing sign should be used adjacent to the crossing location. If thecrossing location is not delineated by crosswalk pavement markings, the crossing sign shallbe supplemented with a diagonal downward-pointing arrow plaque showing the location of

the crossing. If the crossing location is delineated by crosswalk pavement markings, thediagonal downward-pointing arrow plaque shall not be required. To avoid information over-load, this sign should not be mounted with another warning or regulatory sign.

It is important to note that overuse of warning signs breeds disrespect and should beavoided. Care should be taken in sign placement in relation to other signs to avoid signclutter and allow adequate motorist response.

The playground sign (W15-1, as shown in Figure 21.12b) may be used to give advancewarning of a designated childrens playground that is located adjacent to the road. This signis not intended for use on local or residential streets where children are expected. CAUTIONCHILDREN AT PLAY or SLOW CHILDREN signs should not be used. They may encour-age children to play in the street and parents to be less vigilant. Such signs provide noguidance to motorists in terms of safe speed, and the sign has no legal basis for determining

what a motorist should do. Furthermore, motorists should expect children to be at play in



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(a) (b)

FIGURE 21.12 (a) Pedestrian crossing sign (W11-2); (b) playground sign (W15-1).

all residential areas; the lack of signing on some streets may indicate otherwise. Use of thesenonstandard signs may also imply that the involved jurisdiction approves of streets as play-grounds, which may result in the agency being vulnerable to tort liability.

Informational Signs. Guide or directional signs for pedestrians are intended to assist un-familiar pedestrians or those who may not know the most direct route to a destination byfoot. Use distances meaningful to pedestrians, such as the number of blocks or averagewalking time.

Crosswalk Markings. Crosswalk markings provide guidance for pedestrians who are

crossing roadways by defining and delineating paths on approaches to and within signalizedintersections and on approaches to other intersections where traffic stops. Crosswalk mark-ings also serve to alert road users of a pedestrian crossing point across roadways not con-trolled by traffic signals or stop signs. At non-intersection locations, crosswalk markingslegally establish the crosswalk. The standard in the MUTCD is that when crosswalk linesare used, they shall consist of solid white lines that mark the crosswalk. Crosswalk linesshould not be used indiscriminately. An engineering study should be performed before theyare installed at locations away from traffic signals or stop signs. Typical types of crosswalkmarkings are shown in Figure 21.13. Lalani and the ITE Pedestrian and Bicycle Task Force(2001) present an excellent summary of various treatments used by local agencies in theUnited States, Canada, Europe, New Zealand, and Australia to improve crossing safety forpedestrians, including mid-block locations and intersections.

21.6.2 Pedestrians and Work Zones

When construction or maintenance activities take place on or near sidewalks or crosswalks,pedestrians may be exposed to a variety of hazards, including detours that are difficult tonavigate or force pedestrians into the street, uneven walking surfaces, walking surfaces con-taminated with foreign substances, restricted sight distances, and conflicts with vehicles andequipment. In addition, the mobility of persons with disabilities may be adversely affected.It is important to develop and implement temporary traffic control zone policies that mini-mize these problems. All parties involved should be made aware of the needs of pedestriansand made responsible for providing safe and continuous passage.



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PEDESTRIANS 21.31

FIGURE 21.13 Crosswalk markings as presented in MUTCD.

Developing a workable policy for pedestrian access through work areas requires the co-operation of traffic engineers, construction inspectors, crew chiefs, contractors, and advo-cates. The policy should apply whenever construction or maintenance work affects pedestrianaccess, whether the work is done by private firms or city, county, or state personnel.

Permits required for street construction or construction projects that encroach upon side-walks or crosswalks should be contingent on meeting pedestrian access policies. Contractorsshould be given copies of the standards when they apply for a permit. Crew chiefs and crewsshould be trained so that they understand and follow the policy. The Millennium Edition ofthe MUTCD (FHWA 2000) provides more specific guidance than previous editions on pe-destrian access around work a

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Pedestrians Chap 21

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