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Federal Highway Administration > Publications > Public Roads > Vol. 65 · No. 2 > The Marriage of Safety and Land-Use Planning: A Fresh Look at Local Roadways

Sept/Oct 2001
Vol. 65 · No. 2

The Marriage of Safety and Land-Use Planning: A Fresh Look at Local Roadways

by Aida Berkovitz

With the passage of the Transportation Equity Act for the 21st Century (TEA-21) in 1998, Congress for the first time required that states and metropolitan planning organizations (MPOs) incorporate safety and security as criteria in their respective planning processes and activities. However, because TEA-21 did not contain any language explaining or further describing the role that safety and security have in the transportation planning process, the states, MPOs, Federal Highway Administration (FHWA), and Federal Transit Administration (FTA) were left to decide what this meant and how the states and MPOs would address it.

In this article, safety is defined in terms that will help planners, engineers, and other traffic safety professionals see the major role that land-use planning plays in reducing fatalities and injuries resulting from traffic-related crashes, particularly for pedestrians and bicyclists. A national focus on the safety of local roadways is needed, and mixed land use and smart-growth policies can ultimately result in safer local roadways through the use of appropriate designs and slower speeds.

Local roadways are defined here to include rural roads (including minor arterials, major and minor collectors, and local roads) and urban roads (including 50 percent of the principal arterials [other than freeways and expressways], minor arterials, collectors, and local roads).

graphic displaying public road length
Figure 1 — Public road length by ownership in 1999 (in 1,000 miles).

These roadways account for about 76 percent of the public road mileage in the United States, 53 percent of the vehicle-miles traveled, and 63 percent of the traffic fatalities in 1999. They are primarily under the jurisdiction of the counties, cities, and towns and are where we are more likely to make the most improvement in safety for the long term.

Our long-term view of highway safety may need some updating. As our roadways and vehicles get safer, we need to redirect our approaches to make further highway safety gains. Because driver behavior is so difficult to change, we need to develop ways to compel drivers to make the behavioral changes that improve safety.

Defining Safety

Safety is a nebulous term. It is hard to define without a specific context. Safety is like "motherhood and apple pie" — universally accepted as good. Nevertheless, every profession that deals with the subject defines it differently.

Even within the surface transportation community, definitions differ, depending on whether it is defined by highway engineers or rail, transit, or other traffic safety professionals. And the general public may even define it slightly differently than the professionals.

graphic showing vehicle-miles traveled in 1999
Figure 2 — Vehicle-miles traveled in 1999 (in 100 millions).

Highway engineers traditionally define safety as the elimination of the causes of crashes and/or the reduction of the severity of crashes, and as a result, the safety countermeasures they employ will be roadway-related, such as widening shoulders, clearing roadsides, and eliminating sharp curves.

Other traffic safety professionals, including those in law enforcement and public health organizations, state highway safety agencies, and the National Highway Traffic Safety Administration (NHTSA), define safety as the reduction in the numbers and rates of people killed and injured in traffic-related crashes. Their primary countermeasures involve behavioral change.

The public's perception of roadway safety is broader and includes feeling safe and comfortable while walking, bicycling, and crossing streets. Public apprehension about unsafe conditions on local streets, including concern about being a victim of crime, has, among other things, resulted in a generation of children who are driven to school, rather than walking or bicycling.

graphic showing amount of fatal injuries in 1999.
Figure 3 — Persons fatally injured in 1999.

And this has other health and safety ramifications. Childhood obesity has increased 14 percent in the last 10 years, primarily due to inactivity. Children who are driven to school on a daily basis miss the opportunity to learn about their neighborhood environment and to practice the skills needed to judge traffic gaps and speed — skills needed to cross streets safely. Studies show this type of learning can also be important to a child's neurological development.

Developing a Comprehensive View of Roadway Safety

Each of these definitions needs to be incorporated into a comprehensive view of roadway safety. Each has an equal contribution to the larger highway safety picture, and all must be considered by county and city planners. The planners also need new tools that can demonstrate overall safety benefits, rather than just tools that measure the reduction in numbers or rates of crashes.

State and local planners must consider yet another safety issue; they must concurrently deal with efforts to increase bicycling and walking as means of transportation and to reduce the number of crashes involving bicyclists and pedestrians.

graphic showing trends in pedestrian, bicycle, and total fatalities, 1989-1999
Figure 4 — Trends in pedestrian, bicycle and total fatalities, 1989-1999.

The National Bicycling and Walking Study, published by the U.S. Department of Transportation (DOT) in 1994, recommended two national goals:

•Double the current percentage (from 7.9 percent to 15.8 percent) of total trips made by bicycling and walking.

•Simultaneously reduce by 10 percent the number of bicyclists and pedestrians killed or injured in traffic crashes.

If planning for both goals is not done simultaneously, efforts to achieve one goal can hinder the accomplishment of the other. Appropriate city and regional planning can be the key to ensuring that this doesn't happen, and good planning includes a new way to look at the effects of land use on the design of our transportation system.

photo of roadway in San Francisco
This roadway in San Francisco replaced the Embarcadero Freeway that collapsed during the Loma Prieta Earthquake in 1989. The new roadway design has created a promenade for business people who work in the nearby Financial District, other locals, and tourists. The wide sidewalk, street furniture, center raised and landscaped median, and center-island transit stop have made an arterial street into an inviting boulevard with slower and safer traffic for all users. (Photo credit: Aida Berkovitz)

However, these ideas are not new. City and regional planners have known about land-use planning for a long time. The impetus to incorporate pedestrian and bicycle facilities into the roadway design often originates from the bicycling community or environmentalists. The direct connection between land use and safety is much less obvious.

Highway Safety and Roadway Types

In the United States, traffic-related crashes killed 41,611 people in 1999, and 5,656 of these people were killed while walking or bicycling. The majority of these pedestrian and bicycle deaths occur on local streets.

The number of pedestrian and bicyclists deaths and their fatality rates have been decreasing since 1989. The figures provided by the Fatality Analysis Reporting System are only for fatalities, not injuries. Is it possible that our numbers and/or rates of traffic-related pedestrian and bicycle injuries could be increasing? Data that is currently being reported may not be sufficient to accurately gauge trends in pedestrian and bicycle safety.

To improve highway safety, work is generally directed at two primary components: the transportation facilities and the behavior of the users. (To a lesser degree, the vehicle plays a role, but this subject will not be addressed here.) Our safest roadways, in terms of rates of crashes, are freeways. Higher design speeds and limited access make the overall quality and safety of these facilities the best.

The next level of roadway type, the principal arterials and expressways, is predominantly under the jurisdiction of the state DOTs, and these highways get the bulk of the state and federal funding.

Although FHWA and NHTSA put their major safety emphasis on freeways, principal arterials, and expressways, the greatest gains in highway safety can occur on another type of roadway — major and minor collectors, minor arterials, and many major urban arterials. These roads and streets carry the bulk of the day-to-day traffic of most Americans. Unfortunately, many of these roads reflect some of our more noticeable mistakes. As federal and state highway engineers developed better highway safety designs for our highways, they assumed that these "safe" designs should be used everywhere possible. Also, the need to reduce the ever-increasing congestion fed our need to build wider local roads that were designed for higher speed traffic.

graphic of fields of visions for adults and children
Comparison of fields of visions for adults and children. (Graphic by Susan Lockwood)

Residential development patterns common in the post-World War II era greatly influenced commuting patterns; congestion; and the need to build high-volume, high-speed roadways. However, it has become apparent that the demand for more highway capacity cannot keep pace with the immutable, steady suburbanization of America.

The only real solution is to create more travel options. Other travel options are generally viable only where there is compact, mixed land use. This is where the linking of land-use planning and safety is important.

The Inadequacy of Existing Highway Safety Tools

During the early days of the highway safety movement in the mid-1970s, FHWA created separate funding categories for very specifically defined roadway and project types designed to require the states to spend the funds only on projects meeting the criteria. Eventually, these categories were collapsed into two categories — the hazard-elimination and the railroad grade-crossing programs. These two programs are now known as the Surface Transportation Program (STP) safety set-aside funds.

For many years, the hazard-elimination program has worked very well in making safety improvements to our nation's highways. The states use a combination of their crash statistics and known benefits of recognized countermeasures to prioritize their projects. This process works well to reduce vehicle collisions on highways, but it is much less effective for determining safety problems on local streets. One primary reason is that pedestrian and bicycle collisions generally occur randomly — spread out in a neighborhood. And in urban and some suburban areas, collisions involving pedestrians and bicyclists make up a large percentage of all traffic collisions.

Vehicle/pedestrian and vehicle/bicyclist collisions are much more likely to result in a fatality or major injury. A fatal pedestrian or bicycle collision will earn a higher hazard rating than a minor injury collision or a property-damage-only (PDO) collision in a safety analysis. However, because pedestrian and bicycle collision sites are scattered and it is unlikely that many fatal or serious-injury vehicle-to-vehicle collisions will occur at these same sites, the probability that one of these locations will receive a comparatively high hazard rating is very small.

Another problem with the high-hazard location analysis is that it may improve a dangerous location, but it will have very little effect on correcting the real safety problems for pedestrians and bicyclists — wide, high-volume, high-speed roadways and poorly designed, discontinuous, or nonexistent sidewalks.

In addition, these facts don't speak to the issue of pedestrian and bicycle exposure — that is, the rates of pedestrian and bicycle fatalities and injuries. If people seldom walk or ride a bicycle in an area, it is unlikely that someone will get hit there, but that doesn't mean that there isn't a safety problem for pedestrians or bicyclists in the area.

In this situation, the public's definition of safety, which includes the perception of safety, is particularly relevant even though this factor is frequently ignored by professionals. The community sees an unsafe walking or bicycling environment, but the data does not support their observations.

The bottom line is that our existing highway safety tools won't do justice to the safety problems on local roadways.

Characteristics and Behavior-Related Countermeasures

Walking as transportation has been a difficult mode to define. Everyone is a pedestrian at some time, and yet, people vary in cognitive and physical capabilities. Pedestrians are not tested and licensed as drivers are; pedestrians are not required to pass a "walking test." Nevertheless, pedestrian groups have certain different, general characteristics that should be taken into consideration when designing roadways and developing safety programs.

Children have many characteristics that make them particularly vulnerable to accidents. They do not understand danger the same way as adults because they have limited experience and training. They are impulsive and unpredictable, and so, they dart into traffic.

In addition to these behavioral characteristics, they have a number of physical and developmental characteristics that are frequently unknown or overlooked by traffic safety professionals. They have limited peripheral vision and limited ability to determine the source or direction of sounds. Their ability to judge speed is poor, and that handicaps their ability to determine vehicle approach time and gaps in traffic queues. They are shorter and harder to see. They have short attention spans.

graphic showing total U.S. population and pedestrians killed by age group, 1999
Figure 6 — Total U.S. population and pedestrians killed by age group, 1999.

These limitations affect the ability of children to be trained in proper street-crossing techniques. Parental and elementary school instruction on safe walking and crossing behaviors is important but should not be expected to result in a major improvement in the rate of collisions involving child pedestrians. Even so, this is frequently the only type of intervention that many safety professionals rely on for this group of pedestrians. The emphasis of education and enforcement needs to be on the drivers.

The elderly also have physical and behavioral characteristics that make them more vulnerable to death or serious injury as pedestrians. They walk at a slower pace than other pedestrians. Many have impaired vision and hearing. In many communities, senior citizens have a higher than average accident exposure rate because many walk as their primary means of exercise and others walk more frequently as their physical limitations restrict driving. As with children, they can have impaired ability to judge distances and to assess the speed of vehicles and gaps in the traffic stream. Slower walking speed and impaired distance/gap judgment make it more difficult for the elderly to avoid being struck by turning or merging vehicles — the predominant type of pedestrian-involved collision for the elderly. Throw into the mix their physical fragility, and it results in greater risk and likelihood of serious injury or death for an elderly person struck by a motor vehicle.

The majority of pedestrian fatalities and injuries involve adults ages 24 to 64. In 1999, they made up 52 percent of the population but 55 percent of the pedestrian fatalities in the United States. Public outreach campaigns for this broad group are much less likely to be effective than highly targeted campaigns for a specific audience that easily recognizes that the message is meant for them. Special attention may also be needed in communities that have relatively high numbers of immigrants, visitors, or intoxicated walkers.

graphic of speed-flow relationships under ideal conditions (freeways)
Figure 7 — Speed-flow relationships under ideal conditions (freeways).

One group that always requires special attention in the design of pedestrian facilities is the physically disabled. Media and outreach campaigns are usually not the method to improve safe mobility for this group. The Americans with Disabilities Act requires that facilities be built to accommodate the disabled without regard to whether or not any collision problem exists.

Some characteristics and behaviors of physically impaired pedestrians that need to be considered in any driver education campaign or other countermeasure/intervention are:

•They may require more crossing time at traffic signals.

•They may use wheelchairs or motorized scooters, which are shorter and harder for motorists to see.

•They may have impaired vision, decreasing the ability to judge distances and gap/speed assessment.

•They may be hearing impaired.

•They may walk as their only mode of transportation.

The last group are bicyclists, and they can be relatively easily categorized as commuters or recreational bicyclists. Bicycle safety programs tend to concentrate on safe bicycling training for children and on campaigns to increase bicycle helmet use. Driver-targeted campaigns may be an option, but little else in the way of education campaigns is successful.

Along with public education campaigns for pedestrians, bicyclists, and motorists, enforcement efforts are needed to stress the safety message. When used in a comprehensive program, enforcement and education are important elements in improving highway safety. However, campaigns often have limited value over an extended time because when the campaign ends, many of the old behaviors may return.

Facilities for Pedestrians, Bicyclists, and Motorists

The one element that can have a lasting effect on the behaviors of drivers, pedestrians, and bicyclists is the engineering element — building the right type of facilities and building them as part of a comprehensive, community plan. As stated earlier, the answer isn't quite as simple as just making corrections at spot locations or rebuilding a particular hazardous section of roadway. "Traffic calming" — generally self-enforcing, physical design measures designed to force the driver to slow down — is increasingly being used to alter driver behavior and improve safety conditions.

Traffic calming is generally used on residential and semi-residential streets to protect pedestrians and bicyclists. A successful traffic-calming design will slow a driver by using closely spaced physical deflections in the roadway, such as traffic circles or speed humps.

On higher roadway types where vehicle speeds increase, the safety and comfort level of pedestrians and bicyclists decline. A pedestrian hit by a car traveling at 40 miles per hour (65 kilometers per hour) has an 85 percent chance of being killed. At 30 mi/h (50 km/h), the probability of death is 55 percent. If that speed is reduced by another one-third down to 20 mi/h (32 km/h), the probability of a pedestrian death is divided by 11 — reduced to 5 percent. A pedestrian's chance of survival if hit at 20 mi/h is 17 times better than if hit at 40 mi/hr.

Also, anecdotal evidence shows that drivers traveling at higher speeds are much less inclined to stop for pedestrians in crosswalks. Slower vehicle speeds are safer for motorists as well. A slower speed allows a driver more reaction time and reduces the severity of crashes.

As we move up in functional class from city streets and rural local roads to collectors and minor arterials, traffic-calming devices that require deflection are usually inappropriate because these roadways are generally designed for higher capacities and higher speeds. The way to calm traffic on arterial streets is, rather, to force slower speeds by geometric design elements, such as narrow lanes, on-street parking, bicycle lanes, raised medians, roundabouts, bulb-outs, and trees.

It is here that the distinction between the definition of roadway safety by engineers and behavioral safety professionals comes into play. Reconstructing a roadway to a slower design speed, particularly with signalized or stop-controlled intersections, can sometimes result in more frequent collisions. Engineers want to avoid an increase in the number of collisions, but the public and behavioral safety professionals are more concerned with preventing injuries and deaths. To the public, the numbers of collisions are not as important as the potential severity of the collisions.

It does not necessarily follow that high-capacity roadways must have high design speeds. Many collector and arterial roadways could be designed for slower speeds without degrading their volume-handling capabilities. If traffic engineers design for a generous level of service (LOS), then the likely outcome is undesirably high speeds.

The 2000 Highway Capacity Manual describes LOS as "a qualitative measure describing operational conditions within a traffic stream, based on service measures such as speed and travel time, freedom to maneuver, traffic interruptions, comfort, and convenience."

Engineers should equally consider all users when designing local roadways. This requires a better balance of the quality of the experiences of motorists, pedestrians and bicyclists. Using the maximum volume or volume/capacity ratio as a primary design measure may be a more logical focus and can result in a better balance for all users.

In theory, a proper balance would provide the same LOS for both motorists and non-motorized users. But there are also many cases in which a local roadway should have a better LOS for the pedestrians and bicyclists than for the motorists. Looking the graph of the speed-flow relationship under ideal conditions (freeways), we see that as speeds decrease, volumes increase, such that the optimum average travel speed is 30 mi/hr, after which unstable flow conditions with decreased volumes occur. It is, of course, undesirable to design for these conditions on freeways and highways.

If we were to look at the maximum volume/capacity ratio on urban street speed-flow curves, we would see that the optimum volume/capacity ratio curve is similar and that the greatest volumes occur anywhere from a low of 5 mi/h (8 km/h) for class IV streets with 10 signals per mile (1.6 km) to about 29 mi/h (47 km/h) on class I streets with one signal per mile.

photo of sidewalk
This sidewalk in downtown Santa Fe, N.M., proves that even small streets with very narrow sidewalks can be safe for all users. Vehicle speeds are very slow, and vehicular traffic is light. However, pedestrian use is heavy. This photo was taken in the early morning before most vehicular and walking traffic arrived. (Photo credit: Aida Berkovitz)

In the end, both factors (volume and LOS) need balancing — but much more equally than engineers have done in the past. Streets designed at lower design speeds can easily incorporate many of the elements used to slow speeds on collectors and arterial streets.

Many experts in pedestrian and bicycle safety say it is a mistake to apply the same types of LOS criteria to both the driving and non-driving experiences. Free flow, uninhibited conditions for motorists allow them to travel comfortably at any speed they desire. But walking and bicycling are not usually done for speed of arrival. The design of pedestrian and bicycle facilities should be less of a technical analysis and more of a qualitative analysis. The measure of walking comfort cannot be described in the same way as the measure of driving comfort. People generally don't select walking as their preferred mode of transit based on their ability to walk at a chosen speed and with low densities. Any capacity analysis of pedestrian facilities that uses the vehicular LOS definition may result in a poor pedestrian design and an unused facility.

Pedestrians are often intimidated by empty sidewalks and long travel distances, particularly along high-speed roadways. They are "repelled by the starkness of a street, the long line of meaningless buildings, the silly and impossible distances that have been created between places," according to Dan Burden in Walkable Communities.

photo of road with four lanes
Although this is a high-volume, high-speed roadway, the mid-block crossing successfully makes the pedestrian's trek across this street safer with the use of a well-marked, fully actuated signal and a median sidewalk "jog" that forces pedestrians to look in the direction of oncoming traffic before continuing across the other lanes. (Photo credit: Sue Newberry, Community Partners)

Real quality of movement for pedestrians is actually improved with such things as a planted strip set-back from the curb, shade trees, benches, and the other amenities.

"A person in a car is bothered by, but not destroyed by distance. The person needs no added place to sit, nor a fountain to get a drink of water, nor shade, nor a building to go to the bathroom. The pedestrian needs all of these things. People who want to walk want and need more," said Burden.

A safe, comfortable walking environment brings out people in a city. People generally walk for pleasure and experience, not just to get from point A to point B.

A number of practitioners have tried to develop quantitative measures of pedestrian and bicycle LOS. The studies will likely continue, but engineers need to realize that pedestrian and bicycle LOS may be measures that should not be quantified universally. Each community should develop its own definition through an interactive, citizen-participation process — a perfect role for planning.

The Marriage of Land-Use and Transportation Planning

Now the questions to address are, how will planning play a major role and how will we measure that progress?

Land-use and transportation planning need to come together. Designing and building local roadways for all modes — pedestrian, bicycle, transit, truck, and automobile — will have a positive effect on the overall safety of a community.

"The act of walking is particularly risky in metropolitan areas with a large percentage of sprawl development," according to Mean Streets 2000: A Transportation and Quality of Life Campaign Report by The Surface Transportation Policy Project (STPP). "These [areas] tend to be in the newer Southern and Western areas of the country, places that have been built-up since the 1950s and are dominated by subdivisions, office parks, and high-speed roads designed for fast automobile travel."

graphic showing conventional land use
Figure 8 — Conventional land use (graphic by Aida Berkovitz and Brian Huynh).

Besides these conclusions, the significance of this report was that it was the first attempt to define the pedestrian fatality rate based on exposure — number of deaths divided by the pedestrian activity in the community. The current practice for determining pedestrian and bicycle crash rates relates number of deaths to the total population. The use of rates based on exposure — number of feet walked — is more effective for comparison purposes, and it more accurately judges pedestrian safety. For vehicles, we use rates of fatalities or injuries based on 100 million vehicle-miles traveled, which is the recognized standard for determining highway safety progress. No such equivalent exists for pedestrians and bicyclists.

A more recent STPP report, Driven to Spend, further compares the relative transportation costs to citizens living in sprawl areas to the costs to those living in compact land-use communities. The study found that transportation costs actually make up a much larger percentage of the average household expenses than is generally thought. The most powerful source of differences in household transportation spending is related to spread-out development patterns (sprawl) that drive up transportation costs related to automobile ownership and use. People who live in sprawl areas spend more time driving and more money on gasoline and maintenance of vehicles because sprawl requires more frequent and longer trips by car. Transit cannot effectively serve communities with sprawl, thus dooming the citizens to a lack of choice and driving up transportation costs for families who must own multiple cars.

The transportation benefits of mixed land use are now being realized by environmentalists and others because they can see that the consequences of not having it are becoming more pronounced. Many safety problems on our roadways today are a result of the way we have built and continue to build our communities.

The perfect connection of planning to safety is appropriate mixed land use and smart growth planning. Transportation planners need to work with city planners, local and regional elected officials, and other appropriate officials to ensure that good principles of mixed land use are incorporated into local and regional short- and long-range plans.

graphic showing traditional land use
Figure 9 — Traditional land use (graphic by Aida Berkovitz and Brian Huynh).

Mixed land use was the dominant development style in all our cities and towns in the early 20th century — before the automobile was king — and it continued to be the primary pattern until the development of suburbs started after World War II. As suburbs grew in number and size, the new developments were built in patterns now called "conventional." In conventional land-use development, each type of use (residential, commercial, retail, and industrial) is separated from the others.

The growth of suburbs has also had a major influence on roadway patterns in the last 30 years. When comparing the roadway systems of the mixed land-use and conventional development patterns, several distinctions are noticeable. Mixed land use generally has a grid pattern of streets with more total street length, more blocks, more intersections, and more access points. Conventional land-use patterns result in more of a "hub and spoke" or "human circulatory system" roadway pattern.

The various roadway functional classifications are very pronounced in conventional suburban developments. Residential areas are built with cul-de-sacs and a limited number of entry points. Collectors serve as the transition from residential to arterial roadways. A large majority of the trips will be in vehicles, all of which will be funneled onto a few collector and arterial roadways. Because of the limited number of residential access points, the main streets carry higher traffic counts than similarly functioning roadways in mixed land-use development.

In a mixed land-use pattern, more streets mean more choices in route and convenience. Multiple routes and intersections provide more connections and avoid loading traffic on one particular street. Travel distances and times may be lessened, as well as dependency on the automobile. A mixed land-use pattern can ease congestion on main streets by offering acceptable alternative routes, but it will also add through traffic on some residential streets, which makes the need to use appropriate functional roadway design more critical.

Land-use planning is done at the county or city level and has generally been considered planning for economic development. For that reason, transportation planners tend to see their role as advisory rather than decision-making, and they focus on transportation planning to support economic development or capacity enhancements.

Transportation planners need to work with local officials and to show them how their land-use decisions improve the overall transportation system and help achieve community goals. Mixed land-use zoning can have a positive effect on security and economic development. As vehicle trips are reduced and transit use and viability increase, new life is brought to the community, often resulting in the revitalization of the downtown area or village center. Also, the compact, sustainable, and efficient use of land reduces air pollution, vehicular speeds, and the number and severity of crashes. This can lead to a safer and more secure environment, which, in turn, encourages more people to walk, ride bicycles, and use transit.

photo of street and sidewalk
This Salinas, Calif., street is an example of conventional development with a limited number of entry points out of a residential neighborhood. Note the long walking distances required because of the wall and lack of access points into this housing area. Although the sidewalk is wide and nicely landscaped, we see no pedestrians here. The only people who use this sidewalk are those who have no other choice. (Photo credit: Aida Berkovitz)

Planners and decision-makers need to develop some new tools with which to measure safety improvement. Simply projecting reductions in numbers and rates of crashes is not sufficient. The new tools for local roadways must measure enhancements of roadway safety from a broader view.

For example, let's consider one suburban town's situation and solution. A pair of one-way streets that serve a major route to the urban downtown pass through the town's business district and a residential area. Each street has three 11-foot- (3.4-meter-) wide lanes with parking on both sides of the street. The average traffic speed is almost 35 mi/h (56 km/hr). Parallel parking on each side is not permitted during commuting hours. Residents are continuously complaining about high-speed traffic through their neighborhood, and they feel that it is unsafe to allow their children to walk to school because the route requires the children to cross one or both of these major thoroughfares. There are traffic signals at intersections in the business district, but in the residential area, there are only stop signs on the cross streets. Most collisions along this corridor are side-swipes, rear-enders at the signalized intersections, and side-impact collisions associated with traffic turning or crossing from the cross streets. Almost all of these collisions were property-damage-only crashes, but a few resulted in injury.

As a solution for the residents' complaints about safety and the business people's complaints about the parking restrictions near their businesses, the town rebuilt these two roadways. Both streets were converted to two-lane, two-way streets with a 10.5-foot (3.2-meter) lane in each direction, two 5.5-foot (1.7-meter) bike lanes, and parallel parking without rush-hour restrictions on both sides of the street. The sidewalks were widened, and some trees and benches were added in the business district. Highly visible, zebra-patterned crosswalk markings with pedestrian warning signs were added to the two intersections closest to the school. The average speeds came down to about 25 mi/h (40 km/h). The number of collisions remained about the same, but fewer resulted in injuries. Travel times for commuters by car increased slightly, but the number of bicyclists and pedestrians increased. In addition, some vehicular traffic was diverted to alternate routes.

These are the types of overall safety benefits that planners need to define and quantify. However, as indicated previously, specific goals, standards, or measures cannot be determined or applied universally across the country, state, or region. Each town, city, or county, through an interactive citizen-participation process, must determine its own safety needs and solutions.

The Challenge

The challenge in highway safety for the future is to shift some of the emphasis to the lower classifications of roadways and to look at the overall safety picture. Many gains in highway safety have been made in the last 20 years. However, if we don't redirect some of our emphasis, the next 20 years may be the most difficult. As the public health, injury prevention, and preventive health disciplines are starting to incorporate traffic-related injury into their programs, so must the planning and engineering disciplines incorporate new concepts and methods.

We must do the planning to make our local roads safe for everyone, including people who aren't in cars. Appropriate designs that treat all roadway users equally should ultimately affect safety by slowing traffic, thus reducing injuries and deaths. But as we grapple with how to deal with the demands of ever-increasing traffic volume, we'll also need to look at how development and land use affect roadway patterns. The way we plan and build our communities and roadway systems is more likely to have a broader and more sustained effect on traffic safety than attempts to change behavior.

This is our challenge, and it requires a new approach — a comprehensive highway safety approach in which the role of the planner is critical.


Aida Berkovitz is a safety and traffic engineer assigned to FHWA's Western Resource Center in San Francisco. She has been with FHWA for 26 years, working in various field engineering positions, and she has been involved with highway safety programs for about 13 years. For the last two years, she has been working in the National Highway Traffic Safety Administration (NHTSA) Region IX Office as the safety liaison. In that capacity, Berkovitz works on joint agency programs to better coordinate the driver, vehicle, and roadway safety efforts into a comprehensive approach. One of her areas of expertise is in pedestrian safety and design. She serves as a facilitator for the FHWA/NHTSA Pedestrian Safety Road Show and has given many other presentations on the subject at local, statewide, and national venues. Berkovitz has a bachelor's degree in transportation engineering from California Polytechnic State University at San Luis Obispo.

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