September/October
2001
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).
 |
| 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.
 |
| 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.
 |
| 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.
 |
| 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.
 |
|
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.
 |
| 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.
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| 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.
 |
| 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.
 |
| 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.
 |
| 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."
 |
| 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.
 |
| 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.
 |
| 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.
Other
Articles in this Issue:
Low-Altitude
Laser Surveys Provide Flexibility and Savings
The
Marriage of Safety and Land-Use Planning: A Fresh Look at Local Roadways
Strengthening
the Connection Between Transportation and Land Use
Iron
and Asphalt: The Evolution of the Spiral Curve in Railroads and Parkways
New
Life for Old Transmitters: Converting GWEN to NDGPS
Colossal
Partnership: Denver's $1.67 Billion T-REX Project
One-of-a-Kind
Bridge Project Protects National Bird
Partnership
Protects Pristine Estuary and Wetlands
Relationship
Marketing: A Key to Success and Survival