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Step 1 Define the study area. As with the other analyses presented in this guidebook, it is
important to take a critical look at the neighborhoods and infrastructure surrounding the
proposed project and to determine which, if any, are likely to be affected by it. A geometric
change in a roadway, for example, may affect transit routes well beyond the location of the
change.
Step 2 Perform a preliminary inventory of the modes (both motorized and non-
motorized) and facilities available in the study area. Site visits, combined with reviews of
sidewalk, trail, and transit maps, can be used to inventory modes and facilities that the proposed
project may affect--either positively or negatively. Nonmotorized travel data may be available
from existing travel surveys and traffic counts, although conventional sources such as these tend
to under-record nonmotorized trips. Some data sources exclude nonmotorized trips altogether,
and many undercount short trips, nonwork trips, travel by children, and recreational trips.
Automatic traffic counters may not record nonmotorized travelers, and manual counters are
usually located on arterial streets that may be less used by cyclists than are adjacent streets with
lower traffic.
For these reasons, special efforts are usually required to obtain the information needed to
evaluate nonmotorized travel. Whenever possible, the data should be geocoded and incorporated
into a GIS. This makes it easy to create maps that integrate various types of data (such as
roadway and sidewalk conditions) with the demand for nonmotorized travel to identify areas
where effects might be greatest.
Step 3 Examine the demand for alternative modes. This step involves estimating how many
people use (or want to use) alternative modes of transportation. Applying one (or a combination
of) the methods presented in this section, one assesses how many people are likely to be directly
affected by changes to the availability and usability of modes other than the automobile. If
surveys are used, it may be possible to estimate how people value transportation choice as part of
the community, even if some residents currently do not use alternative modes.
Step 4 Evaluate how mobility would be affected by a project. Depending on the scope of
the assessment, an analysis of the use and safety of alternative modes of transportation may
range from a qualitative assessment of the project's impacts on transportation choice to an actual
calculation of the total number of trips or people likely to be affected. Either way, the analysis
results will be enriched by feedback from local planners, officials, and transportation users.
METHODS FOR STUDYING TRANSPORTATION CHOICE
Table 7-4 summarizes the three methods we suggest for evaluating the extent to which
transportation choice exists for protected populations.
Method 7. Modal quality assessment
Qualitative analysis is a screening tool that is especially useful during the design phase of a
project. The analysis answers the question of how a transportation project will affect the number
and quality of transportation choices.
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Table 7-4.
Summary of methods for evaluating transportation choice
Assessment Appropriate Use Data Expertise
Method level uses when needs required
7. Modal Screening Assess demand Design phase when Low Survey
quality for various project will produce methods;
assessment transportation significant changes in graphs, charts,
modes availability of certain maps
transportation modes
8. User demand Screening Assess current Planning phase when Low Survey
and level of use of project will produce methods;
evaluation various significant changes in graphs, charts,
surveys transportation availability of certain maps
modes transportation modes
9. Improved Screening/ Assess current Planning phase when Medium Survey
transportation detailed use and future project will produce methods;
surveys and demand for significant changes in graphs, charts,
models various availability of certain maps
transportation transportation modes
modes
When to use. An assessment of modal quality provides you with a baseline condition of
transportation choice in an area of the community that is likely to be affected by a proposed
transportation project. If the analysis reveals significant deficiencies, they can and should be
addressed in the process of planning for the proposed project. If the project would worsen the
level of choice, either it should be redesigned or substantial mitigation efforts must be carried
out.
Analysis. The analysis has three steps:
1. Identify the transportation modes to be considered.
2. Select suitable standards, guidelines, or indicators for each mode. This selection depends
on two factors:
Overall goals and objectives. For example, an analysis focusing on equity effects
would probably use different indicators of transportation choice than would an analysis
focusing on TDM objectives, such as congestion and emission reduction.
Community preferences. Some communities may place greater weight on a particular
choice or indicator. Consultation with elected officials and public advisory committees
or a public forum may be useful to gauge community preferences.
3. Consolidate material from Step 2 into a small number of indicators that reflect the nature
of the project being designed and the preferences and concerns of affected residents.
Although a qualitative analysis certainly can involve the development of numeric measures, its
principal objective is to give a general idea of who is likely to be affected by a transportation
project and how. Using GIS, it is possible to categorize residential areas according to the number
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of transportation-disadvantaged residents and other attributes that may affect the need for
alternative modes. Incorporated into a transportation model that has been modified to include
alternative modes and transportation-disadvantaged groups, spatial data can indicate how the
project would change transport choice and trip affordability for residents and visitors to the
affected area.
Data needs, assumptions, and limitations. Table 7-5 summarizes a series of simple factors that
indicate whether an alternate mode would help provide mobility for nondrivers, low-income
households, or people with disabilities within the affected area of the community. All of these
impacts are highly relevant to an environmental justice assessment. Additionally, one is able to
assess related quality-of-life factors such as whether it supports TDM objectives such as reduced
traffic congestion, road and parking facility cost savings, and reduced environmental impacts.
Results and their presentation. The results of a qualitative analysis can be presented using
graphs or maps and incorporated into a transportation model. For example, analysis of a
highway-widening project could include graphs showing how pedestrian and cycling level of
service (LOS) would change under various design options (see Chapter 6), along with maps
showing the location of major activity centers (e.g., schools, shops, transit stops, parks, and
recreation centers) and residential areas relative to the project.
Assessment. An analysis of modal quality is a potentially valuable element in an assessment of
the current mobility of protected populations. It also is a relatively simple way to gain a general
sense of how various options for achieving environmental justice objectives might affect the
transportation choices available to residents of a geographic area. Its advantage is that it can be
done quickly for several design options, and it can provide important insights. Using a rather
basic checklist such as that in Table 7-5, one can evaluate the probable effects of each alternative
on the transportation choices of area residents and visitors. Such an analysis can hardly be
regarded as rigorous or definitive, but it can be a useful tool for providing an early warning at a
critical juncture in the development of a transportation project.
Method 8. User demand and evaluation surveys
User demand and evaluation surveys can be used to gather information from travelers who may
be inclined to use a particular transportation alternative. These surveys can also be used to obtain
feedback on the specific barriers and problems facing people who currently walk or cycle on a
particular facility or in a specific area. Such surveys are useful in that they help identify specific
attributes of roadways and their environs that make them especially conducive to travel by means
other than the automobile. The National Highway Institute (1996, Chapter XVI.B) provides
information on user surveys to evaluate bicycle and pedestrian conditions.
When to use. User demand and evaluation surveys are a practical method for assessing the
capacity of an area of a community to enable localized mobility. If an area that is within the
activity space of protected populations would be affected by a proposed transportation project,
this method can be used to assess current capabilities and those if the project were undertaken.
User surveys can be distributed to walkers and cyclists at a study site (e.g., survey forms can be
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Table 7-5. Sample of factors to use in a modal quality analysis
Issue Likely result
K Increase
As a result of this transportation project, traffic volumes are likely to:
K Decrease
K Stay the same
As a result of this transportation project, the number of pedestrian facilities surrounding K Increase
the facility is likely to: K Decrease
K Not change
As a result of this transportation project, the quality of pedestrian facilities (e.g., number K Increase
of cracks or potholes) surrounding the facility is likely to: K Decrease
K Not change
Will the number of pedestrian barriers (e.g., steep inclines or lengthy road crossings) K Increase
increase, decrease, or not change as a result of this project? K Decrease
K Not change
As a result of this project, will residents surrounding the facility have increased, K Increased access
decreased, or the same access to transit stops? K Decreased access
K No change
Are transit service coverage (i.e., the number of routes within a quarter mile), K Increase
reliability, and frequency likely to increase, decrease, or stay the same as a result of this K Decrease
project? K Stay the same
The quality of service associated with paratransit services to residential areas K Increase
surrounding the new facility is likely to: K Decrease
K Stay the same
Are availability and response times for taxi services likely to increase, decrease, or not K Increase
change as a result of this transportation project? K Decrease
K Not change
Will the number of mobility barriers identified by people with physical disabilities K Increase
increase, decrease, or not change as a result of this project? K Decrease
K Not change
The portion of the pedestrian network surrounding the project that meets barrier-free K Increase
design standards is likely to: K Decrease
K Stay the same
As a result of this transportation project, the number of bicycle facilities (e.g., lanes or K Increase
trails) will: K Decrease
K Stay the same
As a result of this transportation project, accessibility of bicycle facilities (e.g., lanes or K Increase
trails) is likely to: K Decrease
K Stay the same
In general, will the proposed transportation project improve, worsen, or not affect the K Improve
environmental conditions for nonmotorized travel in the area surrounding the facility? K Worsen
K Not affect
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passed out along a sidewalk or trail), distributed through organizations (e.g., hiking and cycling
clubs) and businesses (e.g., bicycle shops), or mailed to area residents.
Analysis. Pedestrian and bicycle travel surveys should attempt to gather the following
information:
· Origin and destination of trips, including links by other modes (such as transit);
· Time, day of the week, day of the year, and conditions (such as weather, road, and traffic
conditions); and
· Factors that influence travel choice (such as whether a person would have chosen another
route or a particular mode if road conditions or facilities were different).
A crucial part of this analysis involves identifying specific problems that travelers encounter
when walking and cycling, such as streets with inadequate sidewalks, roads with inadequate curb
lane widths or shoulders, and dangerous railroad crossings. These problems can then be
addressed during the design phase of transportation projects in the area.
Data needs, assumptions, and limitations. The following questions might be included in non-
motorized travel surveys:
· How much do you rely on walking and cycling for transportation and recreation?
· How do you rate walking and cycling conditions in the study area?
· What barriers, problems, and concerns do you have related to walking and cycling in the
study area?
· What improvements or programs might improve walking and cycling conditions?
Note that in some circumstances results may be skewed by the fact that club members, people
who frequent bicycle shops, and people most inclined to return surveys may not be
representative of the entire user population.
Results and their presentation. User survey results should be summarized to highlight key
findings. The results can then be used to identify how transportation choice should be evaluated
and how a particular policy or project is likely to affect transportation options. Standard
statistical analysis techniques can be used to evaluate the accuracy of survey results. Geographic
information can be presented on maps, and time series data can be graphed to illustrate trends.
Results from user surveys can be used to demonstrate mode, group, or location analysis findings.
For example, to analyze the effects a highway project will have on the travel choices of
transportation-disadvantaged people, it may be appropriate to present survey data indicating the
number of people in various groups near the project site (e.g., nondrivers, low-income persons,
and persons with disabilities), their current travel patterns (e.g., how many currently walk and
bicycle along the proposed route), and how these travel modes are likely to be affected.
Assessment. User evaluation surveys are a commonly applied tool for determining the current
circumstances facing pedestrians and cyclists. Problem areas identified in these surveys can then
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be addressed as a transportation project is designed. More specifically, this gives planners a
better understanding of features to avoid or include to facilitate travel by alternative modes when
designing upgraded or reconfigured facilities. By making it easier to travel by modes other than
the auto, those whose resources are severely limited are bound to enjoy greater mobility. As is
true of any user survey, however, the results will reflect only the views and experiences of
current or past users. Those who have not been able or willing to use the various forms of
alternative transportation will not be represented. Thus, it must be recognized that these surveys
are only one useful source of information; they cannot be regarded as definitive for establishing
the needs and preferences surrounding alternative transportation issues.
Method 9. Improved transportation surveys and models
Various conventional travel surveys can be improved to more accurately assess demand for
alternative modes and how this demand would be affected by particular policies and projects.
Most current surveys tend to undercount nonmotorized modes because the walking and cycling
links of motorized trips are ignored (e.g., a walk-bus-walk trip is coded only as a transit trip).
One study found that the actual number of nonmotorized trips is six times greater than what
conventional surveys indicate (Rietveld 2000).
Other limitations of most current surveys include not being sensitive to many factors that affect
public transit demand. For example, most surveys are not sensitive to convenience and comfort
features or to the quality of the pedestrian environment around transit stops. Furthermore, most
current surveys do not consider certain alternative modes at all; they generally exclude
ridesharing, taxi trips, automobile sharing, and delivery services. Most are not very accurate in
predicting the effects of TDM strategies. Finally, many surveys and models are unable to
specifically address travel by transportation-disadvantaged persons.
When to use. In many circumstances, travel surveys can be improved to provide better
information on travel demand for alternative modes, on travel requirements of transportation-
disadvantaged groups, and on functional barriers to the use of alternative transportation. This
information can be of great value when assessing the extent to which a proposed transportation
project would reduce or worsen such functional barriers.
Analysis. Surveys that are sensitive to alternative modes can be analyzed using fairly standard
methods to answer such questions as how basic mobility for transportation-disadvantaged
persons or travel choice by commuters is likely to be affected by a particular policy or project.
In addition to examining direct, short-term effects, the analysis should consider to what degree
the project is likely to contribute to long-term changes that increase automobile dependency and
how this is likely to affect alternative modes. For example, the issues emerging from user
surveys can become a checklist for identifying specific effects of the project that need to be
assessed in the design phase. They also should be factored into go, no-go decisions.
Data needs, assumptions, and limitations. The first step in improving standard travel surveys is
to determine what questions the analysis is to answer. For example, the question might be, "How
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will widening this highway affect the travel choices within the study area?" Answering this
question may require data such as the following:
· Survey data concerning the number of people who have various transportation-relevant
attributes (e.g., nondrivers, low-income persons, persons with physical disabilities,
commuters, and tourists) in the area;
· Survey data concerning the demand for transportation alternatives by the different groups
(i.e., the types of modal attributes they find desirable and within their reach);
· Survey data on the current quality of alternative modes and on the barriers that different
user groups encounter, such as poor pedestrian conditions or inconvenient transit access;
and
· Analysis of survey data that can evaluate how a particular change in the transportation
network would affect alternative modes and their use, especially by protected
populations.
Results and their presentation. Information can be presented in much the same way that
current transportation survey data are presented: using tables, graphs, and maps, with results
disaggragated by mode and demographic group as appropriate. Below are some examples of
ways in which the survey results might be presented:
· Graphs showing the number and quality of travel options currently available to different
groups (e.g., motorists, nondrivers, minority populations, low-income populations, and
those with disabilities) and how these options are likely to be affected by a particular
policy or project;
· Maps showing the location of barriers to walking and cycling identified in a survey and
their relationship to public transit stops, shops, and employment and education centers;
· Maps showing the location of transit access points and retail shops that provide delivery
services and their proximity to residential areas with a sizable population of nondrivers;
and
· Graphs comparing average door-to-door commute times and financial costs between
various residential areas and common workplace sites for travel by automobile and by
alternative modes.
Assessment. Travel surveys have long been an important tool for transportation planners. Such
surveys have been almost entirely directed at the automobile, but it is certainly possible to adapt
them for inquiries into the performance and needs of alternative transportation modes. Knowing
as much as possible about people's concerns regarding current facilities and their desires for
travel by alternative modes will help you assess the extent to which a proposed project would
support these other modes. The surveys also can provide insights into how a proposed design
could be modified to better support travel by alternative modes.
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