Jean-Paul Rodrigue (2013), New York:
Routledge, 416 pages.
1. The Traditional Transport Planning Process
"Long-range plans engender the dangerous belief that the
future is under control." Max Gunther.
Transport planning is usually focused on specific problems or on
broad transport concerns at a local level. It has been traditionally
a preoccupation of lower tier governments, such as the state or municipality.
Because of this fact, transport planning is most developed in the
urban sphere, and it is there where most experience has been gathered.
The planning process, however, has a number of similarities with the
policy process. Identifying a problem, seeking options and implementing
the chosen strategy are essential steps in planning too. Because it
tends to deal with localized problems, the solutions adopted in transport
planning tend to be much more exact and specific than policy directives.
For a long time been planning was a field
dominated by traffic engineers who gave it a distinctly mechanistic
character, in which the planning process was seen as a series of rigorous
steps undertaken to measure likely impacts and to propose engineering
solutions. There were four major steps: Trip generation, trip distribution,
modal split, and route selection. They involved the use of mathematical
models, including regression analysis, entropy-maximizing models, and
critical path analysis.
There are many reasons why the results of these models should be
treated with caution:
The predictions of future traffic flows produced by the four stage
sequence are then used to identify planning options. Since the most
common prediction of the modeling is that present capacities will be
unable to cope with traffic growth, the tendency has been to produce
planning solutions that call for an expansion of capacity. This has
been referred to as predict and accommodate. It is the solution that
has typified so much urban transport planning from the 1940s to the
1980s. It has given rise to the enormous expansion of highway construction
that reinforces the dominance of the automobile. Rarely are there post
mortems of the prediction models, and as has been learned by empirical
observation, the issue of induced demand has distorted the actual
2. Contemporary Transport Planning
In cities traffic problems have increased significantly since the
1970s, despite a great deal of urban transport planning. There is a
growing realization that perhaps planning has failed and that the wrong
questions have been asked. Rather than estimate traffic increases and
then provide capacity to meet the expected growth, it is now accepted
that what is required is better management of the transport system
through new approaches to planning. Just as urban planning requires the
inputs of many specialists, transport planning is beginning to utilize
multi-disciplinary teams in order to broaden the scope of the planning
process. Planning is still a multi-step process, but it has changed
- They are only as good as the data they manipulate and
many times the data is inaccurate or incomplete.
- They are based on assumptions that the mathematical
relationships between variables remain constant.
- They can be manipulated to produce the outcome that
the analyst knows the client prefers.
- Because the predictions were rarely subjected to subsequent
evaluation, their validity is largely questioned, and the modeler
is happy to predict the future since projections rarely question
the validity of the methodology.
Planning is commonly scale specific and multidimensional.
3. Transport Demand Management
In rejecting the former paradigm of building capacity, transport
planners have turned increasingly to managing both demand and the
transport system. Building roads has produced a car-oriented society
in which the other modal alternatives have little opportunity to co-exist. Car ownership is beyond the ability of the transport planner to control
directly and the question remains if it should. But car use and ownership
is affected by land use and density, both elements that planners can
affect. High population densities, in particular, favor walking, bicycling
and public transit use. It is for this reason that a great deal of attention
in planning is being paid to densification and integration. This
includes concentrating development along well served transport corridors
(transit oriented development) and increasing densities in areas undergoing
Managing the demand for transport is made up of a large number of
small interventions that cumulatively can impact of car use, but in
particular improve the livability of cities. A sample of well-practiced and successful interventions
- Goals and objectives. While the goal of traditional transport
policy, improving accessibility, is still useful, it has to be considered
in the context of other desirable goals. For instance improving
safety and health, reducing emissions from vehicles, improving equity,
enhancing economic opportunities, improving community livability,
promoting mobility are all valid. But which goal(s) are pursued
results in a very different planning process. Defining goals becomes
a much more complicated stage in contemporary planning. Increasingly
goals have turned to consider managing demand, rather than trying
to build capacity.
- Options. Given the possible range of goals that transport
planners have to consider, it becomes necessary to provide a set
of possible options. Several objectives may be desirable, and thus
it is important to consider what they imply. Several scenarios may
have to be considered, and they must become important components
of the planning process.
- Identification of actors, institutions, stakeholders.
Given that transport planning has the potential to influence so
many elements of society –economic wellbeing, environmental conditions,
social integration – it is important that those affected by the
transport problem and its potential resolution should be identified
so that they can be engaged. This would be a much wider list of
affected parties than simply those involved in transportation activity
itself, and requires recognizing a role for citizen participation.
- Predicting outcomes, identifying benefits, and assessing
costs. The stage of predicting the outcomes for each of the
options is a critical step in the process. Models continue to play
an important role, but whereas the traditional models were based
on the number of trips, increasingly modeling is becoming more activity
based. Transport is seen in the context of scheduling household
decisions in time and space. Demographic and social data are used
extensively, and the mathematical models have become more sophisticated.
Nevertheless there are roles for other types of analyses, including
non-objective forecasts. The predicted outcomes must then be assessed
as to their benefits and costs. These may be expressed in monetary
terms, but many transport planning situations call for measurement
in other terms, such as visual impacts, environmental dislocations,
and employment impacts.
- Choosing course of action. Evaluation of the scenarios
has to consider the costs and benefits from the frequently conflicting
perspectives of the stakeholders and actors. Extensive public consultation
may be required. The information has to be disseminated and explained
so that an informed public can participate in the debate. Ultimately
it will be the politicians who decide, but they are swayed by the
strength of the arguments presented by the transport professionals,
and in publicly contentious cases by pressure brought to bear by
While planning interventions may have a positive cumulative effect
in shaping transport demand, some economists suggest that a more direct
approach involving imposing more stringent cost measures on car users
is necessary. It is widely accepted that car users pay only a small
proportion of the actual costs of their vehicle use. Economists argue
that the external costs should be borne by the users. As
intuitively rational as this argument may be, there are several problems
with its application:
- Park and ride. Parking spaces are provided, usually close
to an expressway, where drivers can board busses that provide service
to the city center. This has become a staple feature in the
outer zones of many US and British cities. Its success is
variable, however, and there is some evidence from the UK that
park and ride may actually increase car use, as people who may
have used regular bus services now use their cars to drive to
the car parks.
- Traffic calming. Measures that seek to reduce the speed
of vehicles in urban areas, such as speed bumps and street narrowing.
For residential streets the goal is to make their use by car drivers
unattractive because of the obstacles, for thoroughfares the objective
is to reduce the average speeds. The measures indicate the need
for much greater attention to street design and layout.
- Priority lanes for busses and high occupancy vehicles.
Lanes on major thoroughfares and expressways that are reserved for
busses, taxis and passenger vehicles with several occupants. This
has become an important feature of transport planning in North America,
where major highway expansion projects offer priority lanes. The
goal is to encourage use of busses and high occupancy vehicles that
can be seen to travel at higher speeds along the reserved lanes
by other drivers who may be stuck in traffic jams.
- Alternate work schedules. Encouraging work hours other
than the dominant 9 to 5 schedule. One of the great problems in
transport planning is that demand is concentrated in two main peak
periods. In the past, efforts were made to meet this demand by increasing
road capacity, which was never sufficient, and resulted in an under
use of the capacity the other 20 hours each day. Promoting flexible
schedules and encouraging telecommuting are policies that are seeking
to spread out the demand for transport over more hours and even
reducing the demand altogether.
- Promoting bicycle use. In some countries, particularly
the Netherlands, the bicycle is an important mode of travel. It
is a green and healthy mode, but in automobile dependent cities,
the bicycle does not share the roads easily with trucks and cars.
Encouraging greater use of the bicycle requires significant planning
adjustments, such as the provision of bicycle lanes and bike stands.
- Car sharing. Encouraging drivers to share car use with
neighbors or co-workers.
- Enhancing pedestrian areas. In most cities vehicles dominate
the streets. In many areas of high population density, the quality
of life (enhanced safety, less pollution etc.) and the visual attractiveness
of streetscapes can be enhanced by excluding vehicles from streets
altogether, or limiting access to public transport vehicles. In
Europe this has become a distinctive feature of the historic cores
of many cities.
- Improving public transit. For fifty years or more
public transit use as
declined in most cities. Yet it is the
only major alternative to the car in these cities, and thus
enhancing the use of transit has become a major planning
objective. Improvements include making transit more attractive,
by improving bus schedules and improving the appearance and
comfort of transit vehicles and stations. At the same time
efforts are underway to widen the range of transit alternatives.
These include extending commuter rail services, and constructing
new systems such as light and heavy rail modes.
- Parking management. Restricting on-street parking and
charging higher rates for parking.
The effectiveness of economic controls is evident by the experience
of Hong Kong, where, despite high incomes, car ownership and use remains
at a very low level. This is due in the main to the high cost of parking.
An even more drastic example is Singapore, where extreme measures limiting
car purchases, high vehicle licenses, electronic tolls on highways,
and cordon pricing in the downtown area have restrained car use.
The use of pricing mechanisms may be less in other countries, but
the trend towards greater application of some forms of tolling is accelerating.
Cordon pricing has been applied in a number of jurisdictions
access to certain areas, usually the CBD, is tolled. The most famous
application was the decision to charge private vehicles for entry into
Central London in early 2003, a program that has proved to be successful,
despite a great deal of opposition.
Another form of charging is the imposition of tolls on new highways
and bridges. In North America, the public had become used to the
notion that highways are ‘free’, a legacy of the Interstate Highways
Act, funded largely by Congress. In both Canada and the US legislation
now permits private companies to build and operate private roads and
bridges, and to collect tolls to cover costs. In Canada, Highway 407
outside Toronto and the Confederation Bridge linking Prince Edward Island
to the mainland are examples of tolled facilities developed and operated
by private corporations. The same trend applies to developing countries
such as China where many new roads and bridges are toll based.
Another form of pricing is congestion or "fair" pricing. Here
certain lanes of a highway are tolled, but at variable rates. When traffic
is moving freely, the charges for the tolled lanes are nil. But as traffic
builds up and speeds are reduced, the costs of using the reserved lanes
increase. Collection of the tolls is electronic, and drivers are informed
of the current charges by large signs. Drivers are given a choice therefore,
to stay in the slower lanes for free, or move to the tolled lanes at
a cost that is proportionate to the speed on the congested lanes. This
system is now in place in several US States, after successful tests
in California and Texas.
5. Intelligent Vehicles and Intelligent Highways
Technology is seen by many transport planners as a solution to a
wide range of transport problems. This is an approach that has achieved
wide acceptance in the US, where there has always been a strong emphasis
on seeking engineering solutions to urban transport problems. It involves
using information technologies (ITS) to provide better information and
control over traffic flow and individual vehicle use. Many of the solutions
involve the application of remote sensing techniques along with ITS.
One of the most promising approaches involves Interactive Highways.
They are a means of communication between the road and driver that warn
of approaching road conditions. Warnings include electronic message
boards that suggest alternate routes to approaching motorists, designated
radio frequencies that give updated traffic reports. It is based on
a closed-circuit TV system (CCTV) that records lane-by-lane occupancy,
volume and speed. At the same time ramp meters record in real time the
amount of traffic entering the highway. This information is analyzed
and processed at a control center that can dispatch emergency equipment
to accidents as they happen, and can inform other drivers of road conditions,
accidents, construction and delays.
A further technology is Emergency Signal Priority. This is
a means of providing emergency vehicles and public transport busses
priority at traffic lights in congested areas. The system allows a vehicle
equipped with a system emitter to send a coded infrared message to the
system detector, installed at the traffic intersection. When activated,
the detector receives the coded message and then either holds the existing
green light until the vehicle passes through or changes the existing
red light to a green light.
ITS is being applied in many further innovative ways to improve the
efficiency of emergency vehicles. For example, in Montreal mathematical
models are being used to predict where road accidents are likely to
occur given the time of day, traffic volumes and weather conditions.
Ambulances can be assigned to these zones. Once deployed and assigned
to a specific event, optimal routing is determined and relayed to drivers.
When the first responders have identified the extent and type of injuries,
the information is relayed to a control center which determines availability
of doctors and nurses at which hospital emergency room, and suggests
a routing for the ambulance using a least-time model estimation.
ITS is providing many solutions to the problems of road pricing.
Toll collection is increasingly using electronic means to collect
tolls without requiring vehicles to stop at toll booths. In its simplest
form, vehicles equipped with a transponder that emits details of the
vehicle are allowed to pass through toll lanes without stopping to pay.
Receptors at the booth record the passage and debit the account. This
is at the heart of the cordon pricing and of most new toll systems in
This technology, however, is being wedded to global positioning systems
(GPS), which is likely to produce radical changes in the way vehicular
traffic is priced. This combination
of technologies will permit a more effective means of applying road
pricing than the road tax. Vehicles will be required to have an on-board
unit that includes a GPS receiver, a set of digital maps showing jurisdictional
boundaries, an odometer feed, a set of distance rate charges, and a
wireless communication system to report billing data. During each trip
the GPS determines the jurisdictional zones, the odometer calculates
the distance traveled in each zone, and the computer tabulates the running
total of fees, and periodically signals the data to the billing agency.
These systems are presently being evaluated in several states in the
US. A comparable system is already in place in Germany, where since
late 2004 all truck movements are charged an environmental tax based
on distance traveled and vehicle characteristics.
The vast preponderance of transport planning, certainly at the urban
level, has been devoted to passengers. The automobile and public transit
issues have pre-occupied planners since individual mobility can be a
highly political issue (drivers are also voters). Yet freight traffic
represents a significant part of many problems that planning
seeks to address. The models and data inputs used in transportation
planning are of little relevance when applied to freight movements.
For example, demographic data, such as household size, the backbone
of passenger analysis, are irrelevant for freight. The bi-polar daily
peak of traffic movements applies only to passengers, freight movements
being distributed in a different profile over a 24 hour period.
While trucks account for approximately 10% of vehicles on the road,
their size, low maneuverability, noisiness, and high pollution output
make their presence particularly objectionable. Truck pick-up and delivery
in city centers is particularly problematic because of limited parking.
At the same time trucks are vital to the economy and well-being
of society since they provide critical supplies. Commerce is dominated by trucking, and the logistics industry
in particular is dependent on road transport for pick up and delivery.
Garbage pick up, snow removal, and fire protection are among many essential
services that are truck oriented.
Planning for freight movements, such as
city logistics, is still in its infancy. As
a largely private sector activity it is difficult to control, and many
of the decisions that affect trucking are made by the industry itself.
The emergence of large logistics/distribution centers on the outer fringes
of metropolitan areas is taking place without public control or oversight.
In Europe, some attempt to manage such development by establishing publicly-promoted
freight villages has only limited success.
Several cities are seeking to limit trucking as pressures keep mounting
up. In many jurisdictions limits on heavy trucks in urban areas are
in place, and there are restrictions on the times of delivery and pickup, which in some European cities extend to the exclusion of all
trucks in the urban core during daytime hours. The question
remains about to what extent constraining urban freight circulation impairs the
All these steps are tackling the problem at the edges. In many cities
there are no census data on freight traffic, so that planning in the
few cases where it takes place is inevitably hit and miss. There needs
to be a much greater focus on freight planning overall, since it is
almost universally recognized that freight transport is important.
- First, there are difficulties in measuring externalities,
with considerable variations in estimates between different studies.
Different types of use, speeds, engines, vehicle weight, driving
conditions etc. make it difficult to produce broadly accepted values.
Decision makers have difficulty in agreeing to impose charges when
there is a diversity of evidence about external costs.
- Second, there are practical difficulties in collecting these
costs. One of the easiest (and most widely used) methods is
a gasoline tax. It is a crude approach, however, because it imperfectly
distinguishes between driving conditions and engine type – a fuel
efficient vehicle may have just as high consumption in heavy urban
traffic as a gas-guzzler in a rural setting.
- Third, is the political difficulty of imposing such additional
costs on the public. In North America in particular, free access
to roads is regarded as a birthright, and it is intensely
unpopular to propose any new forms of revenue generation that hints
at additional taxation.