Evaluating Transportation Options
~~~~~~~~~~~~~~
TDM Encyclopedia
Victoria Transport Policy
Institute
~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~
Updated
August 27, 2007
This chapter describes the benefits of having a diverse transportation system, and methods for evaluating the value of specific transport options.
Transportation Options (also called Transportation Choice, Transportation Diversity) refers to the quantity and quality of transportation services available to an individual or group, taking into account their specific needs and abilities. There are several reasons that society may value improved Transportation Options, as described below.
·
Solving Transportation Problems. Improved Transportation Options can help reduce
traffic congestion, facility costs, road risk, environmental impacts and
consumer costs.
·
Consumers benefits. Improved options allow consumers to save money, avoid stress, and
reduce their need to chauffeur non-drivers.
·
Efficiency. Consumer choice is necessary for economic efficiency (Market Principles), reflecting the principle of consumer
sovereignty, which requires that markets respond to consumer demands. Improved transportation
choice allows consumers to choose the most efficient option for each trip.
·
Equity. Inadequate transport options often limits the personal and economic
opportunities available to people who are physically, economically or socially
disadvantaged. Increasing transportation options can help achieve equity
objectives.
·
Livability. Many people value living in or visiting a
community where walking and cycling are safe, pleasant and common. There are
also public Health benefits from increased walking and
cycling. As a result, transportation options can help communities become more
“livable,” resulting in increased property values and commercial activity.
·
Security and Resilience. Improved transportation
options results in a more diverse and flexible transportation system that can
accommodate variable and unpredictable conditions. Even people who do not
currently use a particular form of transport may value its availability as a
form of insurance to accommodate future needs.
Different transportation modes serve different roles, as indicated in Table 1. No mode is optional for all purposes. Increasing Transportation Options tends to create a more efficient and equitable transportation system, because it allows each mode to do what it does best. This is particularly important for providing Basic Mobility to people who are economically, physically or socially disadvantaged.
Table 1 Suitability
of Travel Modes
|
Mode |
Non-Drivers |
Poor |
Handi-capped |
Limitations |
Most Appropriate Uses |
|
Walking |
Yes |
Yes |
Varies |
Requires physical ability.
Limited distance and carrying capacity. Difficult or unsafe in some
areas. |
Short trips by physically able
people. |
|
Wheelchair |
Yes |
Yes |
Yes |
Requires sidewalk or path.
Limited distance and carrying capacity. |
Short urban trips by people
with physical disabilities. |
|
Bicycle |
Yes |
Yes |
Varies |
Requires bicycle and
physical ability. Limited distance and carrying capacity. |
Short to medium length
trips by physically able people on suitable routes. |
|
Taxi |
Yes |
Limited |
Yes |
Relatively high cost per
mile. |
Infrequent trips, short and
medium distance trips. |
|
Fixed Route Transit |
Yes |
Yes |
Yes |
Destinations and times
limited. |
Short to medium distance
trips along busy corridors. |
|
Paratransit |
Yes |
Yes |
Yes |
High cost and limited
service. |
Travel for disabled people. |
|
Auto driver |
No |
Limited |
Varies |
Requires driving ability
and automobile. High fixed costs. |
Travel by people who can
drive and afford an automobile. |
|
Ridesharing (auto passenger) |
Yes |
Yes |
Yes |
Requires cooperative
automobile driver. Consumes driver’s time if a special trip (chauffeuring). |
Trips that the driver would
take anyway (ridesharing). Occasional special trips (chauffeuring). |
|
Carsharing (Vehicle Rentals) |
No |
Limited |
Varies |
Requires convenient and
affordable vehicle rentals services. |
Occasional use by drivers
who don’t own an automobile. |
|
Motorcycle |
No |
Limited |
No |
Requires riding ability and
motorcycle. High fixed costs. |
Travel by people who can
ride and afford a motorcycle. |
|
Telecommute |
Yes |
Varies |
Varies |
Requires equipment and
skill. |
Alternative to some types
of trips. |
Each mode is suitable for certain purposes.
Most developed regions of the world are increasingly Automobile Dependent: Driving is relatively affordable, comfort and safety (although in some urban areas driving speeds are reduced at certain time by congestion), and land use patterns tend to be dispersed, which is Accessible by automobile but difficult to reach by other modes. As a result, people who can drive and afford an automobile can generally satisfy their basic transportation needs. On the other hand, non-automobile travel options are often inferior. Walking and cycling is can be difficult and dangerous. Public transit service is often inconvenient and uncomfortable. There is often a lack of coordination between non-automotive modes, so it may be difficult to carry a bicycle on transit vehicles, or reach major transportation terminals by cycling or transit. Interregional travel is often Unaffordable. As a result, concerns about Basic Access often focus on relative inferior transportation options available to non-drivers, particularly those who are physically or economically disadvantaged.
Conventional planning tends to assume that transport progress is linear, with newer, faster modes replacing older, slower modes. This series model assumes that the older modes are unimportant, and so, for example, there is no harm if walking conditions and transit service decline, provided that automobile ownership and vehicle traffic speeds increase. Transportation Demand Management requires a parallel model, which assumes that each mode has a role to play in an efficient transportation system. Transport progress therefore involves improving all useful modes, not just the newest mode. For example, in many situations the best way to improve urban transportation may be to Improve Walking and Cycling Conditions, Improve Public Transit Service, to Prioritize travel or even to Restrict Automobile Travel. Even if this approach does not increase travel speeds it can improve the convenience, comfort and affordability of transport.
Most adults living in developed countries own and drive automobiles, and so may perceive relatively little value from Transportation Diversity. But over their lifetimes, most people experience times in which they cannot drive due to physical or financial constraints, and most large cities have corridors on which traffic and parking congestion limit mobility. If you ask, “What portion of households rely entirely on alternative modes?” the number is generally small, usually under 10% in developed countries, but if you ask, “What portion of households have at least one member that would use alternative modes at least occasionally, if services are adequate?” the number is relatively large, usually 25-50%, and even higher if all Nonmotorized Travel is considered.
A motorist who wants to experience automobile dependency, and the benefits of transportation diversity, can perform a simple experiment: don’t drive for two weeks that involve normal commuting, shopping, and family obligations. You’ll discover that non-drivers face many obstacles, including limited options, high financial and time costs, and poor service. You may experience embarrassment when asking for a ride or when using stigmatized modes such as transit, bicycling and walking. As a result you are likely to travel less overall, foregoing some trips and choosing more convenient destinations for others.
Improved Transportation Options can give people better options for where they live and work. For example, many people want to “age in place,” that is, they want to continuing living in their community as they become older, rather than moving to a specialized retirement community. For this to be possible their community must provide transportation services for people with various needs and abilities, including good walking facilities, support for mobility aids and wheelchairs, transit service and special mobility services. Similarly, lower-income workers, and families with children, have special needs that require a diverse transportation system and Accessible land use patterns.
Transportation Equity is often evaluated in terms of a system’s ability to provide Basic Access to people who are transportation disadvantaged. For this reason, analysis of Transportation Options often focuses on improving mobility options for non-drivers. It can be quite rational for people to support transportation options that they do not currently use, so they will be available if needed in the future. This is called “Option Value.” Most people can expect to go through periods in life when their ability to drive is limited by age, physical disability, financial constraints, vehicle failures or disasters, and so they value the availability of non-automotive travel options.
Transportation Options also include strategies that improve the choices available to motorists, such as Value Pricing, Carsharing, Parking Management, and land use Accessibility factors such as roadway connectivity.
Transportation option analysis is affected by how transportation is measured. For more discussion see Measuring Transportation. FDOT (2002) describes various techniques for measuring Level of Service for various transportation modes.
Transportation is often evaluated based on vehicle traffic or person trips. But movement is not an end in itself; the ultimate goal of most transport is Accessibility (often just called access) the ability of people to obtain desired goods, services and activities. Evaluating transportation in terms of access allows a wider range of solutions to be considered for solving transportation problems. Access is affected by the three factors described below.
·
Mobility - Mobility refers to movement of people and goods. Conventional
transportation planning focuses primarily on mobility, and well-developed
evaluation techniques have been developed for some modes, particularly
automobile and transit.
·
Mobility Substitutes - Telecommunications and delivery services can
often substitute for physical mobility. These are likely to become increasingly
important, and so should be considered in analysis of transportation options.
·
Land Use - Land use can significantly affect access. Higher density, mixed-use
areas have better access because of increased proximity between destinations.
For example, running a dozen errands in an area with dispersed shops and
services may require many miles of driving. In a more accessible area the same
errands may require much less travel and may be performed easily without a car.
Higher population and employment densities also affect transportation options
by increasing demand for transport services, which tend to have economies of
scale. For example, higher-density urban areas usually have more sidewalks and
better transit services than lower-density suburban areas due to greater
demand. Similarly, large employment centers can provide better ridesharing
services.
Analysis of transport options must take into account the integrated nature of the transportation system. For example, the ability to shop without a car may depend not only on the quality and affordability of transit service, but also on the ease of walking between home, transit stops and shops; the ability to carry goods while walking and riding transit; and whether retailers deliver large purchases. Barriers to any of these links limit the utility of transit for shopping.
Efforts to improve Transportation Options can have a variety of goals, some of which are difficult to measure. The five objectives described below are considered practical ways to evaluate how a specific policy or strategy affects Transportation Options (Evaluating TDM). Of course, these objectives can be modified and expanded as appropriate to meet specific needs.
· Non-drivers. Does it improve access or
otherwise benefit non-drivers?
· Low-incomes. Does it improve access or
otherwise benefit people with lower incomes?
·
Physical disabilities. Does it improve access or otherwise benefit people
with disabilities?
· Commuting. Does it improve access or
support other TDM objectives (road safety, reduced environmental impacts) for
commute trips.
· Non-Work Travel. Does it improve access or
support other TDM objectives for non-work trips, including shopping, medical
visits, recreation trip, and tourist travel.
Five practical methods of evaluating transportation options in planning applications are described in this section. For more discussion see Litman, 2001 and Forkenbrock and Weisbrod, 2001.
This method involves identifying and addressing specific problems associated with inadequate transportation options. Examples include:
· Insuring that transportation
disadvantaged patients can access medical services.
· Insuring that elderly
non-drivers can access shops and personal services.
· Providing residents of
economically disadvantaged communities access to education and employment
opportunities.
· Insuring that people with
disabilities can access social and recreational activities.
· Increasing options to allow
motorists who are in a hurry or have other special needs to avoid congestion
delays or use more convenient parking locations.
Planners can identify individual solutions to these transportation problems, such as establishing a single-purpose mobility service, contracting with existing mobility service providers to provide additional trips, changing scheduled transit service to accommodate such needs, or subsidizing taxi service.
This is a common approach to addressing transportation problems. However, it may not be the best approach, because it defines problems and solutions narrowly. For example, providing daytime paratransit service to help elderly residents shop may fail to let them access evening social activities that they consider equally important. Some elderly non-drivers may prefer pedestrian improvements that allow that them to travel to stores on their own, rather than being chauffeured for such trips.
It is therefore important that problems and solutions be broadly defined to find the most effective solutions. Planning for transportation options should include consultation to identify:
This approach involves evaluating policies and projects according to whether they tend to increase or reduce transport options. It recognizes that transportation and land use decisions have cumulative and synergetic effects (Louis Berger & Associates, 1998). Although the impact of an individual decision may appear modest and difficult to measure, their general direction is usually predictable. Rather than trying to model such complex impacts it may be appropriate to simply categorize each decision according to whether it supports or contradicts strategic goals for improving transport options.
For example, if a number of solutions are being considered to help solve traffic congestion problems, the solutions can be rated according to their impacts on transportation options and basic mobility. Some of these, such as transit and ridesharing, increase non-automotive travel options, but others, such as HOT lanes and some Parking Pricing strategies, also increase choices available to motorists. The table below categorizes various polices and programs according to their transportation options impacts. This analysis should be modified to reflect conditions in a particular situation.
Table 2 Policy
Impacts on Transportation Options
|
Tends to Increase Transport Options |
Tends to Reduce Transport Options |
|
Pedestrian
and Cycling Improvements Transportation
Demand Management Programs |
Increased motor vehicle
traffic volumes and speeds. Low-density, urban fringe,
automobile oriented development patterns (Sprawl). Generous parking
requirements. Low-density, homogeneous
land use (e.g., commercial activities are not located in residential
neighborhoods). Pricing that minimizes the
cost of driving (free parking, low fuel taxes, fixed insurance) or increase
the price of alternatives (transit fare increases). Anything that degrades
pedestrian and cycling conditions. |
Some transportation policies and planning decisions tend to increase transportation options, while others tend to reduce options.
This method involves the following steps:
1. Establish strategic goals
and objectives related to transportation options. These goals can be
incorporated into a community’s comprehensive plan or transportation policy
guidelines.
2. Based on these strategic
goals, establish suitable planning objectives. For example, objectives may
include improved walking and cycling conditions, improved transit services, and
increased incentives to use alternative modes.
3. Categorize specific policies and projects according to whether they support or contradict these objectives.
This method involves evaluating individual transport options in terms of their ability to help achieve transportation options objectives. Twenty transport options are listed below.
A variety of land use factors affect access, including density, mix, integration with various transportation modes (such as transit and pedestrian travel). New Urbanism, Smart Growth, Location Efficient Development, Transit Oriented Development and Access Management are examples of specific land use management strategies that can improve access.
Below are possible performance indicators for evaluating land use access.
· Average time and financial
cost for travel between residences and commercial centers.
· Average annual per capita
vehicle mileage.
· Average number of public
services (e.g., schools, shops, medical offices) and employment within a ½ mile
walk of residents.
· Overall quality of transit,
walking and cycling conditions in an area.
· Degree to which zoning laws
and development policies support land use objectives to improve access (e.g.,
urban infill, clustering, Transit Oriented Development, etc.).
· Affordability and quality of
accessible neighborhoods, particularly for people who are transportation
disadvantaged (i.e., can non-drivers afford to live in a nice neighborhood with
good walking and cycling conditions, and good transit service).
Walking is inexpensive, provides Basic Mobility, and is valued for recreation and exercise. Pedestrian improvements benefit most people who are transportation disadvantaged, and support TDM objectives, both directly, and by improving access to transit. Pedestrian access is an important factor in the utility of public transit and ridesharing. For more information see Pedestrian Improvements.
Pedestrian travel is slow, averaging about 3 mph, and even slower for people with physical disabilities. Walking trip distances tend to be short, typically ¼ to ½ mile. As a result, even small changes in the pedestrian network can have a large effect on the feasibility and use of pedestrian travel. For example, reducing pedestrian travel distance by a fraction of a mile can significantly increase the feasibility of walking, particularly for people with physical disabilities, or who carry loads such as shopping or laundry.
Below are examples of performance indicators for pedestrian conditions (see Evaluating Nonmotorized Transport):
·
The number of significant barriers to walking identified by
pedestrians.
·
Portion of streets with continuous and connected sidewalks, paths and
crosswalks.
·
Quality of pedestrian facilities, including functional width, surface
condition, etc.
·
Width and traffic volumes on roads to be crossed, and average crossing
wait.
·
Pedestrian security, including risk of falls and assaults while
walking.
Universal Design (also called barrier-free design) refers to facilities that accommodate people with diverse needs, including wheelchairs users, people who walk with difficulty or have visual disabilities, and pedestrians pushing strollers or handcarts. The term Universal Design is preferred over Handicapped Access because these design requirements can benefit many users, not just those with handicaps or disabilities.
Several planning and professional organizations publish Universal Design guidelines and standards (Evaluating Nonmotorized Transport). Below are possible performance indicators:
·
The number of mobility barriers identified by people with physical
disabilities.
·
The portion of the pedestrian network that meets barrier-free design
standards.
·
Sidewalk, path and crosswalk surface condition (cracks, potholes,
etc.).
·
Availability of information on barrier-free facilities in an area.
·
Ability of transport modes (transit, taxies, interregional buses) to
serve people with disabilities.
Cycling is an important transportation options for some people. It provides basic mobility for many transportation disadvantaged people, is an inexpensive form of transportation that supports TDM objectives, and is a popular form of recreation and exercise. For more information see Cycling Improvements.
Cyclists travel at moderate speeds (averaging about 10 mph), and trip lengths tend to average 1-5 miles. Cyclists’ needs and preferences vary considerably. Some cyclists are comfortable riding on roads with heavy traffic, while others consider even moderate traffic a significant deterrent, and have a strong preference for separated facilities.
Below are some possible performance indicators of cycling conditions (Evaluating Nonmotorized Transport):
· The number of barriers
identified by cyclists.
· Roadway cycling conditions,
including traffic volumes and speeds, lane widths, surface conditions, and
presence of hazards such as potholes and railroad track crossings.
· Existence and quality of
special cycling facilities, including separated paths, bike lanes and paved
shoulder on highways and arterials.
· Existence and quality of
bicycle parking and changing facilities.
Mopeds are small, low-powered motorcycles. They provide an inexpensive form of transportation that reduces parking and some environmental impacts. Mopeds travel at moderate speeds (averaging about 20 mph), with medium trip lengths, that are suitable for local roads but not major highways.
Mopeds benefit some people who are transportation disadvantaged, including people with modest incomes and physical disabilities. Some jurisdictions allow people who are too young to drive other vehicles to use a moped. Mopeds support some TDM objectives, including parking cost savings and fuel conservation.
Below are possible performance indicators of moped transport:
· Roadway cycling conditions,
including traffic volumes and speeds, lane widths, surface conditions, and
presence of special hazards to moped travel.
· Caution and respect for
mopeds exhibited by other drivers.
· Moped crash and injury
rates.
· Affordability of mopeds and
fuel relative to average incomes.
· Existence and quality of
moped parking facilities.
Taxis are an important alternative mode for the following applications:
·
Non-drivers and people who cannot afford an automobile often rely on
taxi travel for basic mobility, including emergencies, errands, shopping, and
sometimes commuting.
·
Visitors to an area who do not have an automobile (i.e., business
travelers and tourists who arrive by airplane, ship or train) often rely on
taxis.
·
Motorists may value having taxi service as a backup option (i.e., when
a vehicle fails, a driver has been drinking alcohol, etc.).
Taxi Service Improvements improve transportation options and provide an important fallback option to people who use alternative transportation modes. Taxi service is often regulated, with restrictions on market entry and pricing, although many communities are shifting to more competitive markets (Regulatory Reform). Informal taxi service often develops in rural communities where certain motorists will drive their neighbors for a fee (Ridesharing).
Below are possible performance indicators for taxi service.
·
Average response time for various conditions and locations.
·
Number of taxis per capita, or per non-driver in an area.
·
Price for an average trip relative to users’ income.
·
Comfort, safety, reliability, and courtesy of service.
·
Number of user complaints over poor taxi service.
·
Number of taxis able to carry people with disabilities (i.e.,
wheelchair users).
Public transit includes various services that provide mobility to the public (Transit Improvements, Transit Evaluation and Transit Oriented Development). Examples including:
·
Fixed route bus.
·
Express commuter bus.
·
Light rail (relatively small, lower-speed trams, in urban areas, with
frequent stops).
·
Heavy rail (relatively large, higher-speed trains, in suburban areas,
with infrequent stops).
There are many ways to improve public transit services, including:
· Additional routes, expanded
coverage, increased service frequency and hours of operation.
· Reduced and more convenient
fares (such as discounts for frequent users).
· HOV
Priority (bus or HOV lanes, queue-jumper lanes, bus-priority traffic
signals, and other measures that reduce delay to transit vehicles).
· Comfort improvements,
including bus shelters and better seats.
· Improved Security
for transit users and pedestrians.