Unfortunately, as a result of the restrictions arising from the CoviD-19 pandemic, it is not currently possible to update the KonSULT website. It is being maintained as a teaching resource and for practitioners wishing to use its Measure and Package Option Generators and its Policy Guidebook. Practitioners wishing to use it, should do so on the clear understanding that recent experience on existing and new policy measures has not been incorporated.

Road User Charging

Urban road user charging (also called congestion charging or road pricing) involves charging drivers for the use of roads they drive on. The charges are designed to reduce traffic congestion (and its associated problems), so an ‘ideal’ charging scheme would vary charges according to location (more expensive in the city centre), time of day (more expensive at peak) and type of vehicle (more expensive for large and polluting vehicles). Road user charging also raises revenue, which may or may not be ploughed back into transport (typically public transport) improvements. Urban road user charging can take the following three basic forms; variations, from simple to complex, are possible on all of them:

  1. Area licensing schemes (ALS): vehicles using the roads within a designated area (and designated time) pay a licence fee, usually related to vehicle type. The Singapore ALS (from 1975 to the late 1990s) was an early example.  The congestion charging scheme in central London applies the same principle.
  2. Cordon pricing (or ‘toll rings’): charging points are located at all entries to a given area (often a city centre), usually with higher charges for large or polluting vehicles and at more congested times of day. Oslo has been operating a toll ring since 1990, and the Stockholm scheme also uses a cordon.
  3. Continuous charging systems: these charge vehicles for all travel within a defined area (such as a city). The charge can be based on distance travelled or time spent travelling, or can involve a charging point on every road link. The complexity means that fully automatic electronic charging (‘electronic road pricing’ or ERP) must be used. Singapore is using an ERP system, which is not yet a truly continuous system, but may become one in the future.

Road user charging can reduce traffic levels in the affected area, typically by 15% to 20%, with more substantial reductions in congestion. Key issues with road charging are its acceptability to drivers (and to others who may be affected by it, e.g. businesses within the charged area), the type and complexity of the chosen technology (manual, video-based, fully electronic), and enforcement.

Congestion, Revenue and Quality

Urban road user charging involves charging road-users for their use of road space over a certain area and/or during a particular time period. It may take a number of different forms, as described below. It has two main objectives: to reduce traffic congestion/control traffic levels; and (related to that) to improve environmental quality, via the reduction of noise and pollution and enhanced streetscape and urban design. It achieves these objectives by seeking to influence the demand for road-use by increasing the cost of travelling by road at certain times, in certain areas and/or along certain routes. A third objective is to raise revenue which can be used to finance other transport measures.

Terminology

The term urban road charging is used, largely inter-changeably, with a number of other terms including:

  • Congestion Charging
  • Road Pricing
  • Road User Charging

The US has adopted the term Value Pricing.

Types of charging method

Most studies and applications are based on point charging in which a charge is levied to pass a point on a road. In this form it is similar to conventional toll systems. Several US Value Pricing applications adopt this approach, with charges to use dedicated lanes, and with exemptions for High Occupancy Vehicles. These have been referred to as High Occupancy Toll lanes.

Point chargingPoint Charging
Cordon ChargingCordon Charging
Area ChargingArea Charging

A charge on a single road is likely to encourage traffic to divert to avoid it and is rarely used except to charge for the use of motorways, bridges and tunnels. Most point pricing systems therefore involve cordon charging (or toll rings) in which a series of charging points are established at all entries to a given area (often a city centre). It is possible to extend this concept to a series of concentric cordons, or cells, or a cordon combined with radial screenlines.

A variant of cordon charging is area charging (or area licensing) in which the charge is levied to use a vehicle within a defined area, rather than just to enter it. This will also control vehicle journeys wholly within the cordon, which are unaffected by cordon charging (and might as a result increase).

Both cordon charging and area charging introduce boundary problems. Through traffic will re-route around the cordon, and may increase congestion; drivers may park outside and walk, adding to environmental problems. Those just outside the cordon will have to pay to travel to the centre; those just inside will not. Drivers making long journeys across the cordon pay the same as those making short journeys. These discontinuities can be overcome by continuous charging systems, which charge for all travel within a defined area (such as a city). These can be based on:

  • distance travelled (distance charging)
  • time spent travelling (time charging)
  • time spent in delay (delay charging)

The last of these requires further definition. One example tested in Cambridge, UK involved charging for any 500m length which took longer than three minutes (Oldridge, 1990).

Variations in charge

Charging has the advantage of being very flexible. The following variations have been considered:

Changes in overall charge level
changes in overall charge level
Charging in one direction or two
charging in one direction or two (for cordon charging)
Different charge levels on different cordons
different charge levels on different cordons (for cordon charging)
Varying charges by time of day
varying charges by time of day
Varying charges by type of vehicle
varying charges by type of vehicle
Exemptions, or reduced rates, for specified types of user
exemptions, or reduced rates, for specified types of user (e.g. residents, disabled drivers)
Credits which provide a limited number of free journeys
credits which provide a limited number of free journeys
Caps which limit the amount which can be charged in a defined period
caps which limit the amount which can be charged in a defined period (e.g. a day, a month)

Technology

In discussing the technology options available for the implementation of Road User Charging, one has to distinguish between the payment process and the enforcement process.

It is possible to operate cordon charging or area charging using simple pre-purchased paper licences. This system operated in Singapore for several years. However, enforcement has to be manual, and can be expensive, and drivers must spend time purchasing licences. Also the ability to vary charges is more limited.

A relatively low technology alternative is to use Automatic Number Plate Recognition (ANPR). Drivers purchase a permit, and their vehicle is then added to an electronic list; automatic cameras record vehicles crossing cordons (or within areas) and check number plates against the list. This is still only feasible for cordon charging and area charging and variations in charging are still limited.

Cordon charging systems in Singapore and Norway now use fully electronic systems (ERP) in which the vehicle has an on board unit, in which a smart card is inserted. When the vehicle passes a charging point, it is detected, interrogated to identify the on board unit, and a charge deducted from the smart card. Vehicles detected without an on board unit or smart card are photographed for enforcement purposes.

Time charging could operate in a similar fashion with the on board unit switched on to charge the smart card (at a specified rate per minute) when the vehicle enters the area and switched off when it leaves it, or when the engine is stopped.

Distance charging and delay charging would either need a link to the odometer in addition, or need to use GPS to identify vehicles' locations. GPS (Global Positioning Systems) (these are also known as Global Navigation Satellite Systems (GNSS))  are most appropriate for distance based charging systems but again ANPR is used to identify occasional users and to capture image-based evidence sufficiently reliably to be acceptable in court. It is likely that GNSS systems will become the accepted way to impose all forms of urban road charging in due course, particularly since they can also provide other services such as driver information systems. However the technology is still being developed and there are still technical issues in urban canyons (i.e. roads that are surrounded by tall buildings) which may limit the accuracy and precision of the system.

The traditional cash based toll collection systems (i.e. payment of tolls at a toll plaza) combine charging and payment into one event. For electronic charging methods, we need to differentiate between charging and payment. The charging and payment processes are strongly linked to the enforcement process, regardless of the choice of charging technology. It has been argued that the three electronic technologies described in the table below are not competitors, but should be regarded as complementary.

Dedicated Short Range Communication (DSRC) permits vehicles to be identified and localised for enforcement purposes. When the vehicle passes a charging point, it is detected, interrogated to identify the on board unit, and a charge deducted from the smart card. Vehicles detected without an on board unit or smart card are photographed for enforcement purposes and Automatic Number Plate Recognition (ANPR) technology is used to identify exempt vehicles or allow for enforcement.

A charging system cannot exist without enforcement. An enforcement strategy needs to be based on three fundamental objectives:

  • ensuring that charging policies and payment rules are followed by all road users,
  • informing and raising awareness of scheme requirements to deter non-payment and
  • ensuring that the fees are paid.

Technological Options for Implementation of Road User Charging

Technology

Applicable Charging System/example

Advantages

Disadvantages

Implications for Enforcement

Manual toll collection

Point based/ (e.g. Trondheim, Norway up to 2005)

Highly reliable and accepted

Creates congestion around toll collection areas

Land take required for toll plazas

Act of Payment and Enforcement combined in one.

Paper Licences

Point or cordon based
(Singapore, 1975-1998)

Simple

Limited number of classes possible 

Difficult distribution, purchase arrangements and enforcement

Enforcement may be difficult and require manual observations.

Automatic Number Plate Recognition (ANPR)

Point or cordon based
(e.g. London)

Most mature

Requirement for street furniture
High costs

This is primarily technology for enforcement and not for collection.

Dedicated Short Range Communication (DSRC)

Point or cordon based
(e.g. Singapore 1998 onwards)

Can be used with a variety of charging designs

Requirement for street furniture

This is primarily for collection (ANPR still used for enforcement).

Global Positioning System (GPS)/  Global Navigation Satellite Systems (GNSS)

Distance, time- based, entire network (e.g. German Heavy Vehicle Charging)

Most sophisticated

Street furniture required for enforcement

May be operational problems with urban canyons and nearby routes

High costs of on-board units
Technology still being developed

This technology allows for simultaneous charging and enforcement.


Why introduce urban road charging?

The underlying argument for urban road charging is that road users should be directly charged for the additional costs which their use of road space imposes on the rest of society. Economists argue that charges for goods and services should reflect the costs imposed on society by the users of those goods or services. Whilst the users of urban road space themselves bear some of the costs which they impose (delay to their journey, increased risk of themselves being involved in an accident, exposure of themselves to local air pollution), the additional costs to the rest of society which their use of road space imposes (delay to other road users, the increased risk of other road users being involved in an accident, exposure of others to local air pollution etc) are not fully charged for.

The current failure, in many towns and cities, to fully charge for these additional costs means that charges are currently too low. It is generally recognised that the charge levied for a good or service will influence the quantity of that good or service that people demand. Hence, if charges are too low then demand will be too high, resulting in congestion, environmental degradation and increased risk of accidents. Urban road charging, therefore, seeks to correct for this and, hence, to re-allocate road space according to road users' willingness to pay. In doing so, this will lead to a reduction in traffic and will generate revenue which can then be invested in useful projects.

The European Union funded CURACAO project (CURACAO, 2009a, 2009b), through a survey of a number of cities across Europe,  found that the primary objectives of road user charging were as follows:

a) congestion relief 
b) environmental protection
c) generating revenues for transport investments.

In addition, other objectives for road user charging included the following:

  • Protecting economic growth
  • Health
  • Liveability
  • Safety
  • Promoting equity and Social Inclusion
  • Protecting future Generations

Demand impacts

The impacts of urban road charging are, almost exclusively, on the demand for road travel, and particularly travel by car. This determines the way in which it contributes to transport policy objectives. Urban road charging could impact on people's demand in a number of different ways and the precise way in which it will do so will differ according to the situation.

Responses and situations
Response Reduction in road traffic Expected in situations
Where the system only operates during limited hours or where charges are different at different times of day
Where the origin or destination is not in the charged area and where alternative routes, which avoid the charged area, are available and attractive
Where an attractive alternative destination exists and is not subject to charging and where individuals have the flexibility to change. Some such alternative destinations may involve shorter journeys, e.g. to local facilities, where as others may involve longer journeys, e.g. to neighbouring towns
Where there is potential to link journeys together, to work or shop from home or to otherwise re-arrange activities
Where public transport is available and attractive, there is potential to car share or potential to walk or cycle. The response to change mode may go hand in hand with other responses, e.g. changing destination to use local facilities and walking to those local facilities
Where individuals’ reduction in car-use over a sustained period is so significant as to make owning a car uneconomic and where individuals believe that charging is part of a longer term transport strategy. In the first instance, this is more likely to apply to a household’s second or third car
Where this assists individuals to make any of the above responses and where it is recognised that charging is part of a long term transport strategy responses
= Weakest possible response = Strongest possible positive response
= Weakest possible negative response = Strongest possible negative response
= No response

Short and long run demand responses

Demand responses to urban road charging in the short run are likely to be different from those which might take place in the longer run. This is because certain decisions which have major impacts on people's travel behaviour, such as where to live and whether or not to own a car are not generally subject to review in the short run.

Demand responses
Response - 1st year 2-4 years 5 years 10+ years
-
  -
  Change job location
- Shop elsewhere
  Compress working week
- Trip chain
- Work from home
- Shop from home
  Ride share
- Public transport
- Walk/cycle
  -
  -
= Weakest possible response = Strongest possible positive response
= Weakest possible negative response = Strongest possible negative response
= No response

Level of response

Price elasticity of demand will also vary according to context. Important factors influencing the calculation and interpretation of price elasticities include: the size of the price change; the type of pricing mechanism; the type of trip; the type of traveller; the price of related goods and services; and whether the elasticity accounts for short term or more long term demand responses. Hence, care should be taken, if applying price elasticities, that they are based on a similar context to that in which they are being applied. Whilst there are few estimates of the generalised cost elasticity of demand for car travel, Lee (2000) reports estimates of short run generalised cost elasticity in the range -0.5 to -1.0 and estimates of long run generalised cost elasticity in the range -1.0 to -2.0. Before applying these generalised cost elasticities to urban road charging one would need to calculate by what percentage the introduction of urban road charging would alter the generalised costs of car travel. A relatively moderate charge might increase generalised costs by approximately 10% which, it is suggested, would decrease car travel by at least 5% in the short run and by at most 20% in the long run.

Supply impacts

Urban road charging would not usually involve any change in overall road supply, except where road closures or other traffic management measures have to be implemented in order to make a cordon system work. However, because demand is reduced, the amount of road space available to each individual vehicle is increased. Furthermore, in order to cope with expected increases in demand for public transport it may be necessary to increase public transport supply in advance of the charge being implemented.

Financing requirements

Certain forms of urban road charging are cheaper to implement than others. This depends principally on the complexity of the system, the technology chosen and the system of enforcement.

The following cost and revenue estimates were calculated for two studies of the feasibility of urban road charging in London, based on a simple central London scheme:

  Licence Tag Smart Card
Implementation costs £30-50M
£85M £140M
Annual operating costs £30M - £50M
£55M £55M
Revenues

£150M -£570Mpa

£150M - £570Mpa £150M - £570Mpa

Annual operating costs for the London scheme have turned out to be significantly higher than shown in the table above and currently stand at about £91 million per annum (TfL, 2008).

Expected impact on key policy objectives

Urban road charging encourages people to change their car travel behaviour. It firstly encourages them to change the timing and location of their car journeys from congested and environmentally sensitive times and places, e.g. peak hours in city centres, to less congested, less sensitive times and places. Secondly, it encourages them to reduce their overall level of car-use, either by switching from the car to other transport modes or by reducing the amount they travel. Therefore, its main contributions will be to objectives concerned with efficiency and environment. It will also generate substantial revenue, which can potentially be used to finance other elements of a transport strategy (May et al, 2005).

Contribution to objectives

Objective

Scale of contribution

Comment

 

By reducing delays, improving reliability and prioritising high value trips

 

By improving streetscape and urban design and by reducing community severence

 

By reducing air and noise pollution and pressures on green space and environmentally sensitive sites

 

By improving public transport conditions and releasing revenue which can be used for the ‘common good’, though the equity effects will depend on how the revenue is spent

 

By reducing traffic levels and evening out traffic speeds

 

By freeing up potentially productive time currently lost in congestion and by enabling freight operators to rationalize their fleet operations

 

By raising substantial amounts of revenue on an on-going basis

= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Expected impact on problems

Urban road charging could significantly reduce car use in the charged area, and hence reduce delays, unreliability, environmental impact and accidents. Traffic would divert to boundary routes, other times of day and other modes; much of the transfer would be to bus, which would benefit from the reduced congestion. Careful design is needed to ensure that these alternatives do not themselves become congested, and for cordon schemes, the location of the controls is critical. Subject to this, congestion charging can achieve significant road user travel time, environmental and safety benefits. It will also generate substantial revenue, which can potentially be used to finance other elements of a transport strategy (May et al, 2005).

Contribution to alleviation of key problems

Problem

Scale of contribution

Comment

Congestion-related delay

By reducing traffic volumes though re-routing and re-scheduling may transfer problems elsewhere

Congestion-related unreliability

By reducing traffic volumes though re-routing and re-scheduling may transfer problems elsewhere

Community severence

By reducing traffic volumes and enabling some roads to be closed

Visual intrusion

By reducing traffic volumes and land-take

Lack of amenity

By discouraging longer journeys and enhancing the viability of local facilities

Global warming

By reducing traffic-related CO2emissions

Local air pollution

By reducing emissions of NOx, particulates and other local pollutants though re-routing and re-scheduling may transfer problems elsewhere

Noise

By reducing traffic volumes though re-routing and re-scheduling may transfer problems elsewhere

Reduction of green space

By reducing pressure for new road building and city expansion

Damage to environmentally sensitive sites

By reducing traffic volumes

Poor accessibility for those without a car and those with mobility impairments

By enhancing the viability of public transport and by discouraging car-oriented development

Disproportionate disadvantaging of particular social or geographic groups

By enhancing the viability of public transport and reducing traffic levels in residential areas, though people living on the boundary of the charged area may also experience disbenefits

Number, severity and risk of accidents

By reducing traffic volumes

Suppression of the potential for economic activity in the area

By freeing-up time previously spent in congestion and by improving the efficiency of the local road network

= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Expected winners and losers

We would not necessarily expect everyone to directly benefit from the introduction of urban road charging. The table below highlights the main groups of people who we would expect to be direct beneficiaries, as well as those who we would expect, in the first instance at least, to lose out. It should be remembered, however, that this only relates to the direct, immediate impacts and that the revenue generated from urban road charging would, depending on how it is used, enable everyone to benefit. For example, it would be possible to use some of the charging revenue to reduce general business taxes on small businesses or to reduce income tax for people on low incomes.

Winners and losers

Group

Winners/Losers

Comment

Large scale freight and commercial traffic

High value journeys – less time spent in congestion the greater the vehicle utilization – relatively small proportion of journey distance in urban conditions.

Small businesses

Some small, local businesses will find themselves spending a high proportion of their time in the charged area, potentially resulting in a large proportionate increase in their transport costs, though they are likely to benefit from reduced congestion.

High income car-users

High income associated with high value of time and, hence, highly valued time savings from reductions in congestion, and charge is likely to be a relatively small proportion of disposable income.

Low income car-users with poor access to public transport

Low income car-users may be inconvenienced by being deterred from making particular car journeys, although they may find that improved public transport makes it an attractive alternative. Overall impact will depend significantly on how revenues are used.

All existing public transport users

These people will face an increase in their transport costs but will find it difficult, in the short run at least, to change their travel arrangements and behaviour. However, increased demand for alternatives may result in their increased availability.

People living adjacent to the area targeted

Reduced congestion will result in enhanced reliability and reduced journey times for public transport, whilst increased demand for alternatives should result in increased supply; a possibility of increased over-crowding but overall impact dependent on how road pricing revenues are used. Traffic levels in the area where they live may increase or decrease depending on the location.

People making high value, important journeys

If using car then they are likely to benefit from improved speed and reliability (although at some extra financial cost). If using public transport, then in the longer term at least, the quality of service should have improved.

The average car user Average car-users with middle incomes will tend to either be encouraged to change mode (or making some other alternative arrangements) or will pay the charge which, because of their value of time, may not represent good value to them i.e. the decongestion benefits will not compensate them for the charge. Overall impact dependent on how road pricing revenues are used.
= Weakest possible benefit = Strongest possible positive benefit
= Weakest possible negative benefit = Strongest possible negative benefit
= Neither wins nor loses

Barriers to implementation

Scale of barriers
Barrier Scale Comment
Legal Requires special legislation in many countries.
Finance Raises revenue.
Governance Coordination needed between adjacent authorities, particularly to avoid spill over effects.
Political acceptability Highly contentious, given expected serious opposition by car owners and other affected road users.
Public and stakeholder acceptability Any increase in the costs of motoring is seen as very unpopular.
Technical feasibility Some systems require complex technology.
= Minimal barrier = Most significant barrier

The Singapore Area Licence Scheme

Singapore introduced an Area Licensing Scheme in 1975 to reduce congestion in the city centre. Drivers had to purchase licences for a day or a month to allow them to enter the defined area between 0730 and 1015. The initial charge was S$3; this was raised to S$4 in 1976. Vehicles with four or more occupants were exempt. Police at the 22 entry points observed vehicles and recorded those without licences; they were then fined. Subsequent modifications involved extensions to the evening peak, the working day and Saturdays, to a set of charging points on expressways, and to all cars however many occupants they had. Different charges were levied for different types of vehicle. A major study was conducted in 1975 (Holland and Watson, 1978); the evidence below comes from this.

Impacts on demand

Pattern Most affected drivers continued to travel to the city centre; there were no recorded reductions in numbers or length of journey or destination.
Mode 19% of drivers travelling to the city centre switched to bus; 17% switched to car sharing to take advantage of the exemption for cars with four or more people.
Timing 22% of drivers travelling to the city centre switched to travelling before or after the charged period, resulting in some increases in congestion then.
Route Many drivers travelling through the city centre diverted to the ring road, resulting in some increases in congestion on that route; a few changed mode or time of travel.

Surprisingly there were very few changes in evening peak travel; it appeared that people continued to use their cars to leave the city centre in the evening peak, even though they had made changes in the morning.

Impacts on supply

Only minor adjustments were made to the road network, and no delays were caused at the entry points. However, drivers did need to spend time purchasing licences. It should be noted that whilst overall supply of road space has not changed, because each vehicle on the road impacts upon the supply available to all other vehicles, the supply of road space and therefore "quality of service" for each vehicle is greatly improved.

Contribution to objectives
Objective Scale of contribution Comment
  The reduction of 44% of traffic entering the centre resulted in an increase in speeds of 22% in the centre and 10% on the approaches. Speeds fell by up to 20% on the inner ring road. No comprehensive cost-benefit analysis was conducted, but it is clear that there were substantial reductions in congestion costs and increases in benefits. It is possible that charges were, in practice, too high and that greater benefits could have been obtained by a smaller reduction in car-use.
  The scheme’s impact was primarily on the commercial and business centre of the city. Residential streets were therefore little affected, but there was an improvement in conditions in shopping streets and the business district.
  This was not a key objective and no attempt was made to assess impacts. However, it can be expected that it was improved in the city centre in the morning peak, with some minor deterioration outside the controlled periods and on the inner ring road.
  The study attempted to identify gainers and losers, but found little evidence of differential impacts, and suggested that the range of alternatives offered reduced the scale of any inequities. A subsequent study, however, suggested that poorer car-drivers had been adversely affected (Wilson, 1988).
  This was not a key objective and no attempt was made to assess impacts. However, it can be expected that it was improved in the city centre in the morning peak, with some minor deterioration outside the controlled periods and on the inner ring road.
  An attempt was made ten years later to identify impacts on the urban economy and business relocation. None were found; they had been dwarfed by the expansion of Singapore’s economic base. Businesses were very supportive of the scheme.
  In 1975 prices costs were approximately S£60M, the operating costs S£1m PA, and revenues approximately S£7M PA. Although revenue-raising was never an objective, the scheme raised substantial net revenues; operating costs being only 12% of revenues.
= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Singapore Electronic Road Pricing

Context

In 1998 the Area Licensing Scheme was replaced by an Electronic Road Pricing Scheme. 97% of the 700,000 vehicles in Singapore were fitted with on board units, in which smart cards were inserted. Gantries at the Area Licensing Scheme entry points and expressway charging points were equipped to identify, interrogate, charge and, if necessary for enforcement, photograph, all vehicles passing. Charges are now levied per crossing rather than per day, and vary by time of day and vehicle type. Charges are revised quarterly to maintain speeds at between 20 km/h and 30 km/h in the city centre, and 45 km/h and 60 km/h on expressways. As a result charges are lower than with the Area Licensing Scheme for much of the day and have been waived on Saturdays. Early results are now available (Menon, 2000).

Impacts on demand

Pattern There is no evidence of any further impact on the origins and destinations of journeys.
Mode It may be that there have been some changes in mode, given the further reduction in traffic levels, which are 15% below those under the Area Licensing Scheme.
Timing Drivers appear to be very sensitive to differences in change by time of day. In addition the number of multiple entries was substantially reduced.
Route There is no evidence that further changes in route have occurred, although there are still some congestion problems on the boundary route.

Impacts on supply

Capacity has been maintained, and the delays involved in purchasing licences removed.

Contribution to objectives
Objective Scale of Contribution Comment
  No detailed analysis has been conducted but it seems probable that, by targeting charge levels to achieve optimal speeds, efficiency has increased.
  As with area licensing, there was little impact on residential streets
  This was not a key objective. There will have been some limited further reduction in environmental impact through the further reduction in traffic
  No assessment of equity impacts has been made, but those making occasional journeys off-peak and on Saturdays will have benefited, while costs will have increased for those making multiple journeys.
  This was not a key objective. There will have been a limited further reduction in accidents through the further reduction in traffic.
  It seems very unlikely that there will have been significant impacts on the urban economy.
  The cost of introducing electronic road pricing was substantial, at S£200M. Revenues are, in practice, lower than with area licensing, at S£8M per annum, but revenue generation is not an objective.
= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Toll rings in Bergen, Oslo and Trondheim

Context

In 1986 Bergen, Norway's second largest city, was the first city in Europe to introduce a toll ring (or cordon) charging system. It was introduced with the objective of raising the finances required to accelerate the implementation of a wide-ranging programme of transport investment. The system charges all vehicles (other than buses in regular service) a flat fee for entering the city's central business district and operates between 6AM and 10PM Monday-Friday. Toll rings were subsequently also introduced in Oslo and Trondheim. As in Bergen, the main objective is to raise revenue so charges are set according to revenue goals, though both Oslo and Trondheim use electronic toll collection and in Trondheim tolls were differentiated by time of day.  The Trondheim toll ring was removed in 2005, when the programme of investments had been fully paid for.  The toll rings in Bergen and Oslo have been maintained, with new programmes of investment.

Impact on demand

Pattern In Bergen, whilst it was expected that the ring would decrease traffic volumes by around 3%, other than a slight decrease in the beginning there has been an average annual traffic growth of 2-3%. In Trondheim there have been significant impacts on peak hour traffic levels, with reductions of 10% immediately following the introduction of the differentiated charges, reducing still further over time to 17% below the precharge level.
Mode It is likely that there has been some change in modal share over the period, though this will have been in part due to the investment in public transport, using the revenues from the toll rings, which has taken place over the period.
Timing Reductions in peak traffic in Trondheim resulting from the differentiated charge were outweighed by increases in traffic in off peak periods.
Route In Bergen, there are no natural detours so there has been little impact on route choice.

Impact on supply

The toll rings themselves have not affected overall supply, though the finance they have generated has enabled a series of major transport projects to be implemented. It should be noted that whilst overall supply of road space has not changed, because each vehicle on the road impacts upon the supply available to all other vehicles, the supply of road space and therefore "quality of service" for each vehicle is greatly improved.

Contribution to objectives
Objective Scale of Contribution Comment
  No detailed analysis has been conducted but it seems probable that, in Trondheim at least, efficiency will have been increased via the targeting of the charge on peak period traffic.
  The schemes are focused on the central business districts. Residential streets are therefore likely to have been little affected, though there may have been an improvement in conditions in the central shopping streets.
  This was not a key objective. There is likely to have been some reduction in environmental impact through the reduction of traffic.
  No assessment of equity impacts has been made, but those making occasional journeys outside the charging periods, eg on Saturdays, will have benefited while costs will have been imposed on those travelling during the charging periods, eg during the peak periods in Trondheim. Opinion polls originally indicated that approximately two thirds of Bergen’s population were against the toll ring, though it has now been widely accepted by the majority. The change in opinion is thought to be connected with the visible improvements in the local transport network benefiting everyone and is despite relatively high levels of tax on motoring.
  This was not a key objective. There may have been a limited reduction in accidents through the deterrence of car travel, though this is likely to have been offset by increase in road capacity.
  In Bergen, Saturday was deliberately kept free from tolls in order to support the city’s shops. However, the effect on city centre shopping is not known. A study in Trondheim found that there had been no adverse impact on the city’s economy (Tretvik, 1999). The reduction in congestion is likely to have boosted productivity which may have impacted on economic growth.
  In Bergen the initial investment to establish the ring was approximately NOK 15M (€1.85 million). Annual income has been higher than expected and is approximately NOK 70M (€8.645 million). Of this, NOK 50M is spent on roads, NOK 14M is taken up in operating costs and NOK 7M is stored in a fund (the use of which attracts great political debate).
= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

For more information see www.brotunnel.no

Value Pricing in San Diego

Financial and technical support from the US Federal Highways Administration (FHWA) has been used to facilitate the implementation of several pricing projects which have come to be known as 'value pricing' schemes.

The first significant value pricing project was implemented in 1996 along the 13km high-occupancy vehicle (HOV) section of Interstate 15 (I15) in San Diego. Access to the HOV lane was extended to include a limited number of solo drivers who were able to pay for a monthly pass for use of the HOV lane during peak periods. The number of available passes rose gradually from 500 to 900 over the first year and the cost of the pass rose from $50 to $70. Then, in March 1998, the pricing scheme was upgraded to become an automated, dynamic system. Congestion in the HOV lane is monitored and formed the basis of the toll levels. Tolls are set with the aim of maintaining 'free-flow' conditions in the HOV lane and range between $0.50 and $4. They vary as often as every 6 minutes and the current toll level is displayed on a real-time sign post in advance of the entry to the lane. Tolls are deducted using transponders and over-head readers. A similar scheme has since been introduced in Houston, Texas. In addition, higher peak fees on existing toll roads and bridges have been introduced in Lee County.

Impacts on demand

Pattern Traffic volumes along the section of I15 increased 'moderately (by approximately 6%)', comprising a significant (48%) increase in volumes in the HOV lane (as paying users took up the spare capacity which existed in the HOV lane prior to the introduction of value pricing) and a slight decrease in volumes in the other I15 lanes. The overall increase during the peak was smaller than was observed in the 'control' corridor. But peak spreading is certain to have meant that overall traffic flows increased.
Mode Some diversion to express bus services is indicated, though this would appear to have been a relatively minor impact.
Timing The main impact has been to divert trips from the peak; both from the middle of the peak to the 'shoulder' of the peak and from peak to off-peak.
Route No evidence reported.

Impacts on supply

By freeing up the spare capacity in the HOV lane for use by non-HOV users, the I15 value pricing scheme has, in effect, increased the overall capacity of the road. In addition, the revenues it has generated have provided funding for a new express bus service along the corridor.

Contribution to objectives
Objective Scale of Contribution Comment
  Conversion of the HOV lanes to HOT has used up spare capacity in that lane so improving efficiency in the short-term. Revenue has paid for a bus service which may also have improved efficiency. Redistribution of trips to either side of the peak also improves efficiency. There has not been any apparent reduction in car-sharing. Cost benefit analysis over a 20 year period showed the scheme to be a success.
  Not in an area where people live or work but the peak spreading observed may have reduced liveability in such areas that are origins and destinations connected by I15.
  Reduced congestion in the short-term but perhaps in the longer term less incentive to car share and so higher traffic levels. Overall traffic levels almost certainly increased and so CO2 emissions likely to be higher. But the scheme did fund an express bus service.
  No evidence presented but it is likely to be the more wealthy that pay the charge for the HOT lane, the revenue raised has then been used to fund an express bus service which may benefit the socially excluded.
  No evidence presented but better distribution of traffic either side of the peak may have reduced accidents but on the other hand increased overall volumes may have led to an increase.
  No evidence presented but likely to be beneficial.
  The scheme provided revenues which under state law had to be used to fund transport improvements along the corridor. The net financial impact is therefore neutral.
= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Congestion charging in London

Context

The London congestion charge was implemented in February 2003. The key elements of the scheme as it was originally set up are set out below:

  • Scheme operates on weekdays between 7 a.m. and 6:30 p.m. in the area of Central London, as shown in the map.
  • Cars, vans and lorries charged £5 to operate within the zone.
  • Exemptions include motorcycles, licensed taxis, vehicles used by disabled people, some alternative fuel vehicles, buses and emergency vehicles.
  • Area residents receive a 90% discount for their vehicles.
  • Payments can be made on the Internet, at payment booths in the area, with text messages and at retail outlets displaying the congestion charge logo such as newsagents.
  • Cameras automatically check the number plates of eligible vehicles driving into and within the zone. The numbers are automatically checked against a database of vehicles that have paid the charge. If the charge has been paid the number is deleted from the database (avoiding privacy issues) with only those vehicles that have not been paid for having the details stored. If the vehicle has still not been paid for by 2400 that day then a fine of £80 is issued. This is reduced to £40 if paid within two weeks.

In July 2005 the basic daily charge increased to £8. The map shows the area covered by the original scheme. In February 2007 the scheme was extended to cover an area of similar size to the west, with the boundary between them retained as a free route. It is now proposed to remove this western extension and revert to the original scheme.

Congestion Charging Zone and Residents Discount Area

Congestion charging signs at the edge of the zone (left), public telephone with Internet payment (middle), cameras within the zone (right)

Impacts on demand

The charge has had a dramatic impact on travel demand in the capital. The following is reported in TfL's monitoring study:

  • Vehicle kilometres (vehicles with four or more wheels) in the charging zone during charging hours were reported to have dropped by 15% in the first year whilst the number of vehicles entering the charging zone during charging hours was down by 18%. These levels of traffic reduction were largely sustained in the first three years of implementation. Both of these outcomes were towards the top end of the range of TfL's predictions.
  • The increase from £5 to £8 resulted in further a reduction of around 4% in traffic entering the charging zone.
  • Small increases in traffic observed on the inner ring road which forms the boundary of the charging zone.
  • Outside of the charging zone more generally there was no significant evidence of an increase in traffic as a result of the scheme.
  • Congestion in the zone during the charging period dropped in the first year by approximately 30%. Subsequently there has been some dilution of this impact.
  • Total numbers of trips into the area have been relatively unaffected with car users transferring to London Underground, buses, trains, cycling, powered two wheelers, taxis and walking.
  • Numbers of pedal cycles entering the zone during charging hours have increased by around 25%.

Traffic entering the charging zone during charging hours

When the scheme was first introduced in 2003, total traffic entering the charging zone fell by 14% (Table 1), in line with forecasts, but the actual reduction in cars entering the zone was much larger (33%). The reduction in cars entering was offset by increases in buses (as part of a planned strategy to allow for mode shift) as well as taxis, motorcycles and cycles, which are exempt from the charge.

Table 1: Traffic Entering Central London Charging Zone

2003 vs 2002

2007 vs 2002

All vehicles

-14%

-16%

Four or more wheels

-18%

-21%

Cars

-33%

-36%

Vans

-11%

-13%

Lorries

-10%

-5%

Licensed Taxis

17%

7%

Buses and Coaches

23%

31%

Powered Two Wheelers

13%

-3%

Pedal Cycles

20%

66%

Source: TfL(2008)

The longer run impacts (comparing 2007 vs 2002) are also important since there may be a time lag for traffic to adjust to the changed conditions produced by charging.  While it is clear that the reduction in the number of cars entering the zone has stabilised at around 36%, the initial increase in powered two wheelers reported in 2003 has subsequently been reduced to less than the pre-charging numbers in 2002. However there is a sustained increase in the number of pedal cycles (albeit from a low base) and this seems to be increasing.  In addition when the fee was raised from £5 to £8 in July 2005, TfL surmises that there was only a relatively “indistinct aggregate traffic volume response” in terms of traffic flows entering in the congestion charging zone (TfL, 2007 p.19).

The fact that drivers paying the charge can drive all day at no extra charge leads to the possibility that those vehicles (and those that are exempt) may take advantage of the less congested conditions by increasing their mileage within the zone. The table below indicates that this has not been a significant problem with vehicle kilometres (vehicles with four wheels or more) within the zone showing the same percentage reduction as numbers entering the zone shown in the table above.

Year-on-year percentage change in vehicle kilometres driven within the charging zone during charging hours, annualised weekdays for 2002-2007

 

2003 vs 2002

2004 vs 2003

2005 vs 2004

2006 vs 2005

2007 vs 2006

All vehicles

-12%

-5%

+1%

+1%

0%

Four or more wheels

-15%

-6%

0%

+1%

-2%

Potentially Chargeable

-25%

-6%

-1%

+3%

-1%

-cars and minicabs

-34%

-7%

-1%

+4%

-4%

-vans

-5%

-4%

-4%

+3%

0%

-lorries and other

-7%

-8%

+8%

+2%

+9%

Non Chargeable

+18%

-3%

+4%

-3%

+2%

-Licensed taxis

+22%

-7%

+5%

-5%

-1%

-Buses and coaches

+21%

+5%

-1%

+4%

-11%

-Powered two wheelers

+6%

-2%

0%

-4%

+2%

-Pedal cycles

+28%

+4%

+14%

-1%

+17%

The figures below illustrate that the charge has not caused a major displacement of traffic to the times of day either side of the charging hours. Furthermore, after an initial "spikiness" that is evident in 2004, traffic distribution throughout the day is settling down to take a shape very similar to that before the charge.

Traffic entering the charging zone by time of day. Annualised weekdays for 2002 (pre-charging), and 2003-2007 (post charging), all vehicles

chart 1


Traffic leaving the charging zone by time of day. Annualised weekdays for 2002 (pre-charging), and 2003-2007 (post charging), all vehicles

chart 2

Impacts on supply

  • Reduced congestion improved bus performance dramatically with excess waiting times falling by 30% in the first year and a further 18% in the second year.
  • Further improvements in the quality of the bus service were achieved through a substantial increase in the bus fleet, paid for from charging revenues.
  • Taxis benefited from reduced congestion with increased speed and reduced cost to passengers.
  • Measures have been implemented to improve the "level of service" for walking and cycling.
  • Measures to improve priority for bus services, walking and cycling and certain public realm schemes have led to a small reduction in capacity for private vehicles.

Several surveys have suggested that the impact on London’s economy has been broadly neutral.

Other Impacts

Accidents

The table below shows significant drops in accidents in the charging zone and inner ring road. Part of this reduction can be attributed to the congestion charge itself but the majority is likely to be due to other safety initiatives, some of which have been made possible by the congestion charge. That part of the reduction in accidents can be attributed to factors other than the congestion charge is clear from the reductions in accidents for the rest of London.

Total reported personal injury road traffic accidents by area, 2001 to 2004

Monetarised Costs and benefits

The table below summarises an economic evaluation conducted in 2005.

Summary of principal annual operating costs and road user benefits (£ millions, 2005 prices and values, charge at £5)

Research by other authors has questioned TfL's conclusions. Prud’homme and Bocajero (2005) conclude that the charge is an economic failure. However, other commentators (Mackie, 2005; Raux, 2005) have taken issue with some of the detail of their assessment. 

Contribution to objectives
Objective Scale of contribution Comment
  The significant reductions in congestion with transfer to more sustainable modes represents a major increase in economic efficiency. Operating costs are high however and do reduce the net economic benefit of the scheme. Total benefits are £200 million per annum with total costs including extra buses at £110 million. This gives a net annual benefit of £90 million. TfL figures are not universally accepted however, particularly regarding the values of time used, and so there is still some degree of uncertainty over the efficiency case.
  There is strong evidence that the reduced levels of traffic and the increased space and priority for pedestrians and cyclists represent a significant improvement in amenity in the zone. Major increases in traffic diverting around the zone have not been an issue.
  Reductions in vehicle traffic and congestion have reduced emissions of CO2 by 15.7% in the zone and 8.5% on the inner ring road. Local pollutants in the zone were down by 13% and 16% for NOx and PM10 respectively; whilst both pollutants were down by 7% on the inner ring road.
  No evidence presented on equity and social inclusion directly but the improvement in public transport and bus services in particular, improved amenity for walking and cycling and reduced accidents are all likely to disproportionately benefit the socially excluded.
  Between 60 (-2.8%) and 140 (-6.5%) fewer accidents are estimated to occur in the zone and inner ring road as a result of the scheme. The savings have been given a monetary value of £15 million per annum.
  The overall conclusion is that the impact on London’s economy has been neutral.
  Revenues (including penalties) for the financial year 2007/2008 were £268 million. However it is recognised that the system is very expensive to operate and more could be done to reduce the costs (which amounted to £131 million). Hence net revenues were only £137 million i.e. 50% of the revenues were spent on operating the system.
= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Stockholm

Context

Stockholm, the capital city of Sweden, has 765,000 inhabitants in the municipality and 1.9 million in the whole county. High levels of traffic and a radial infrastructure network make the transport system in Stockholm very constrained. About 500 000 vehicles pass in and out of the inner city every weekday. A full-scale congestion charging trial took place in Stockholm for 7 months in 2006, followed by a referendum. Following an overall “yes” from the citizens of Stockholm City, the congestion tax was permanently installed in August 2007.

Motivation of road user charging in Stockholm

The primary objectives of the trial were to reduce congestion, increase accessibility and improve the environment. During the trial, the revenue was earmarked to provide more resources for public transport. In the permanent scheme however, revenue is to be used to finance new road infrastructure investments. The charging trial was accompanied by a package of improvements in public transport and park & ride facilities.

Features of the Stockholm scheme

The congestion tax is levied when entering or leaving the inner city zone between 6.30 am and 6.29 pm Monday to Friday. Charges vary from €1-2 depending on the time of day, with a maximum amount of €6 per vehicle and day. Payment rules/modes have evolved since the trial, and now the vehicle owner is debited monthly by invoice. Payment is not possible at the control points. Eighteen control points are set up at the borders of the charging zone, and vehicles are registered automatically when passing (see Figure 1 [check numbers!]). Stockholm is built on islands, with a limited number of bridges leading to the inner city, which has contributed to reducing the number of control points. The main source of identification is through photographing the number plates. During the trial on board units were also used by some vehicle owners, but then removed essentially for administrative reasons. The congestion tax law applies only to vehicles registered in Sweden with the following exemptions:

  • emergency service vehicles;
  • buses;
  • diplomatic cars;
  • motorcycles;
  • foreign-registered vehicles;
  • military vehicles;
  • vehicles with disability parking permits;
  • alternative-fuel cars;
  • vehicles passing through the city centre to and from Lidingö Island within 30 minutes
  • vehicles that only by-pass Stockholm via E4 Essinge link.

Stockholm map
Figure 1: Location of the Stockholm Cordon (Numbered are the toll cordon points where entry and exits are deducted and the caption in Swedish translates as “Charge is not payable if using the E4 Essinge link”) (Source: CURACAO, 2009b)

Impacts on demand

The trial in 2006 was subject to an extensive evaluation in a multitude of dimensions, some of which are still being monitored during the permanent scheme. The effects contained here are related primarily to results found during the course of the trial.

Major conclusions are:

  • Traffic decreased by 22 % (over the charge period) at the cordon during charging hours. These effects were immediate and stable.

Table 2 shows the changes in traffic flows comparing the pre-charging scenario (Spring 2005) vis-à-vis the post-charging scenario (Spring 2006). We distinguish the changes by time period as the toll paid varies by time of day.

Table 2 Changes in Traffic in Congestion Charging Zone Comparing Spring 2006 (post charging) with Spring 2005 (pre charging)         


Locale

Morning Peak
(0700-0900)

Evening Peak
(1600-1800)

Charge Period
(0630-1830)

Full 24 hours

Congestion Charging Zone (Entering/Exiting)

-16%

-24%

-22%

-19%

Major Inner City Streets

-7%

-10%

-10%

-7%

Minor Inner City Streets

-8%

-13%

-10%

-8%

Source: Stockholmsförsöket(2006b), Table 1, p. 13

The recorded 22% reduction during the charge period shown in line 1, column 3 of Table 1  [check] pertains to an aggregation of changes in traffic entering/exiting the congestion charging zone over the 18 control points (see Figure 1). At the individual level, traffic passing through (in both directions) the congestion charging control points fell by between 9% (4,000 vehicles) and 26% (9,000 vehicles) during this same period.  The smallest reduction of 9% was recorded on the control point leading to/from Lindingö island and this is primarily attributable to the exemption for traffic to and from Lindingö which crossed the charging zone within 30 minutes.  On the other hand the largest recorded decrease of 26% was attributable to drivers diverted onto a parallel bypass corridor instead of travelling through the charging zone.

Traffic on the major and minor inner city streets was not reduced by as large an extent as traffic entering. This does not seem surprising since traffic circulating entirely within the congestion charging zone is not required to pay the toll (Eliasson et al 2009).

Table 3 shows changes in traffic on the radial roads approaching the cordon and the outer link roads and the outer city roads. Comparing Table 2 with Table 3, the reduction in traffic on the outer approach roads is much less than the reduction achieved within the charging zone.

Table 3 Changes in Traffic for Radials and Outer Approach Roads Comparing Spring 2006 (post charging) with Spring 2005 (pre charging)    


Locale

Morning Peak
(0700-0900)

Evening Peak (1600-1800)

Charge Period (0630-1830)

Full 24 hours

Outer approach roads

-3%

-4%

-5%

-5%

Outer link roads

4%

4%

1%

0%

Outer city roads

-5%

-4%

-5%

-5%

Source: Stockholmsförsöket(2006b), Table 1, p. 13

Delays (excess travel time during the peak) were reduced by 33 % on arterials leading to the city.   The observations from the Stockholm trial indicate that there have been substantial reductions in delays due to congestion charging (Eliasson et al 2009; Stockholmsförsöket,2006b). In line with the reductions in traffic mentioned earlier, there has been a corresponding reduction in travel times. The maximum reduction occurred on arterial roads with travel times 50% of those in the spring of 2005 before charging began.  On the other hand there are areas in which the travel times have increased. In the first instance, traffic on the Essingeleden bypass experienced increases but these were not statistically significant when compared to the day to day road network variability (Stockholmsförsöket, 2006b). Another significant source of increase in journey times was on Södra Länken but the expert group report attributes this to the road already carrying traffic volumes far exceeding its original designed capacity (Stockholmsförsöket, 2006b).

Re-distribution of traffic with respect to time-of-day was less than expected. The Stockholm results showed that the time-of-day effects were much smaller than anticipated. While the authorities expected to see peak spreading on a much larger scale due to the differentiated charges, the available data did not substantiate this hypothesis. Instead the data showed that there were no time periods during which traffic over the cordon increased to avoid other time periods when charges were higher.

Public transport patronage increased by 6 % over the trial period.

Impacts on Supply

  • Several Public Transport Routes were extended. 
  • Park and Ride sites were introduced but these did not prove to be hugely successful or well utilised.

Other Impacts

  • No effects on retail at aggregate level
  • The distributional effects (benefits and costs) vary among groups. Effects for disadvantaged groups were generally smaller than effects for middle and high income groups
  • It was difficult to determine whether inhabitants experienced an improved city environment as this was considered subjective.
  • Sustained vehicle fleet transition to electric cars which are exempted from the charge 
  • Acceptability changed from a negative majority before the introduction to a positive majority. This is important because when the referendum was held even those who had to pay the charge (i.e. those living within the cordon) (since the charge was for both entering and exiting the cordon) were in favour of keeping the pricing system.
Contribution to objectives
Objective Scale of Contribution Comment
  Delays (excess travel time during the peak) were reduced by 33 % on arterials leading to the city. This would have led to substantial time savings.
  No discernable impact of this was reported but anecdotal evidence suggests that the centre is now more pleasant.
  There was a reduction in vehicular emissions within Stockholm of between 8-14%.
 

Households with high discretionary income (income/household member) pay nearly three times as much as households with low discretionary income. (Transek 2006)

  It was not possible to discern any changes in safety impacts from the results .
  The congestion charges did not seem have any impact on retail. (Dauntfeld et al (2009); Eliasson et al (2009))
 

The yearly revenue is in the region of €50 million.

= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Zone a Traffico Limitato (Limited Traffic Zones), Rome, Italy

The information source is: CURACAO(2009b)

Context

Rome is the capital of Italy.In the last 35 years in the metropolitan area of Rome there was a threefold leap in terms of vehicle kilometres travelled, due to the increased length of trips and number of vehicles (+650%). This growth has not been matched by a parallel development of the public transport system, which has only recorded a 90% increase in terms of kilometres travelled during the same period. Consequently, the public transport modal share, with 56% of total motorised trips in the late 70s, has sharply decreased and today accounts only for 24% of motorised trips.  

Presently the city of Rome has a population of 2.8 million inhabitants, with 1.96 million cars and more than 550,000 motorcycles and motor scooters circulating in the city. The mode choice for travel in Rome is split between 52% using private vehicles (excluding motorcycles and scooters), 24% for public transport and 24% for powered two wheelers (i.e. motorcycles and scooters), walking and cycling. The pressures of so many people and vehicles have created two interrelated problems, traffic congestion and environmental degradation. Therefore Rome's General Traffic Master Plan includes a strategy to improve mobility, modify modal split in favour of public transport and sustainable modes, increase traffic safety, decrease air and noise pollution, safeguard health, and preserve Rome's historical and architectural heritage. The strategy is to restrict or limit private car use in the city centre and gradually relax these restrictions outside.

As part of this Master Plan, Rome has implemented an access control system. This is known as “Zone a Traffico Limitato” (ZTL). The first implementation, supported by electronic gates, was in 1st October 2001, in order to safeguard the central area of the city (“ZTL centro” in Figure 2). Once the automatic system had been tested and fine tuned, other “sensitive areas” and “sensitive time bands” were identified and the scheme extended (Figure 2 and Figure 3).

A fixed fee valid for a period of time (allowing vehicles to travel in or through the charged zones) is payable. The fee varies for different categories of vehicle. The charges for the different vehicle categories are  set out in Table 4.

Table 4 Charges for various categories of vehicles

Category

Charge

Disabled

€15 for 5 years

Freight distribution

€ 55 for 5 years

Private taxi

€55 for 5 years

Residents

€55 for 5 years, €300 (2nd registered vehicle per annum), €550 (3rd registered vehicle per annum)

Non residents (private)

€550 (per annum)

Public Utilities

€550 (per annum)

Coaches

Daily charge

Daily Permits

€20/day (max 560€/year)

Note that powered two wheelers are exempt from the charge.

Rome map
Figure 2: The daily  ZTL Scheme in Rome (Dots indicate the gates equipped with ANPR technology for enforcement)


Rome map night
Figure 3: The night time ZTL Schemes in Rome (Dots indicate the gates equipped with ANPR technology for enforcement)


The chargeable areas and time periods in which they operate are summarised in Table 5 below:

Table 5: Zone Definition and Hours of Operation

Area

Time Band

Coverage Area

Technology

ZTL CENTRO(day)

Monday to Friday: 6.30am-6.00pm
Saturday 2pm-6pm

4.15 km2

23 Electronic Access gates equipped with Automatic Number Plate Recognition (ANPR) Technology (for enforcement)

ZTL CENTRO (night)

Fridays and Saturdays: 11pm – 3am

-

23 Electronic Access gates with equipped with Automatic Number Plate Recognition (ANPR) Technology (for enforcement)

ZTL TRASTEVERE  (day)
ZTL TRASTEVERE  (night)

Monday to Saturday: 6am-10.30am
Friday and Saturday: 9pm-3am

0.97 km2

12 Electronic Access gates with vertical signalling and ANPR

ZTL SAN LORENZO LTZ (night)

Fridays and Saturdays: 9pm – 3am

0.26 km2

7 access roads, Electronic gates

ZTL TESTACCIO (night)

Fridays and Saturdays: 9pm – 3am

0.45 km2

11 access roads controlled by the Police

ZTL MONTI (night)

Fridays and Saturdays: 9pm – 3am

-

4 access roads, Electronic gates

ZTL VILLA BORGHESE

24 hours (public park)

1.5 km2

3 access roads, Electronic gates

It is important to point out that the definitions of the ZTL boundaries differ depending on the hours of operation. However the Access Gates to the ZTL (shown as dots in Figure 1 and 2) are equipped with Variable Message Signs to indicate if the ZTL is in operation.

Impacts on demand

Table 6 shows some before and after survey data reported in CURACAO (2009B) pertaining to the changes in modal share. The ZTL has led to an approximate 5% reduction in the level of private car use.  The majority of these have transferred to pedestrian traffic (3%) but since powered two wheelers are exempt from the charge, there has been a consequent increase in this mode.

Table 6:  Change in Modal Share before and after scheme implementation

 

Modal Share

 

Public Transport

Private Cars

Motorbikes/Mopeds

Pedestrians

Before

30%

27%

23%

20%

After

31%

22%

24%

23%

Source CURACAO (2009B)

Traffic Impacts

Reduction in traffic flows of around 20% (averaged over all  ZTL areas over hours of operation) and by 15% for the morning peak (8:30-9:30) over all ZTL areas operating during the day. However, there are still violations. The proportion of illegal accesses decreased from 18% at the start of the scheme in 2001 to less than 10% of the total traffic flows in 2007.

Impacts on Supply

The supply of road space has not been directly affected by the schemes.

Contribution to objectives
Objective Scale of Contribution Comment
  There was an increase in average speed of 4% during the peak hours, which suggests a reduction in congestion and improvement in efficiency. At the same time, public transport (bus) travelling speeds have increased by 5% leading to improvements in congestion related unreliability. 
  Residents were generally in favour of the scheme as it improved the liveability of the areas affected. 
  Comparing mean values of CO, PM10 and Benzene before and after the scheme was introduced show reductions in pollution levels of 21%, 11% and 27% respectively. However there is some evidence to suggest that this might also be due to advances in engine technology (CURACAO 2009b)
 

No information was specifically available on this.

  No information was specifically available on this.
  There were no registered impacts on economic growth.
 

Total revenue from the scheme amounted to €90m (2007). 

= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

“Ecopass” Milan

The information source is: CURACAO(2009b)

Context

Milan, the capital of Lombardy region of Italy, has a population of 1.3 million people. It is the biggest industrial city of Italy with a multitude of industrial sectors..  Milan has the third-highest concentration of particulate matter (PM10) among large European cities, both in terms of average annual levels and days breaching a European Union limit of 50 micrograms per cubic metre (CURACAO 2009b).

Hence in a bid to reduce pollution, the City of Milan introduced a road pricing scheme known as EcoPass for all polluting vehicles entering the main city centre area of Cerchia dei Bastoni. EcoPass came into effect on 2 January 2008 as an innovative way of improving mobility and safeguarding both public health and the environment. Unless otherwise stated, the effects reported here are from the first year of the scheme operation.
The objectives of EcoPass were to:

  • Improve air quality by reducing PM emissions in the Cerchia dei Bastioni (approximately the city centre of Milan) by 30%, with a positive effect on the surrounding areas of the city as well;
  • relieve congestion by reducing the number of incoming cars by 10% and thereby speeding up public transport in the area; and
  • boost public transport by reinvesting all EcoPass charges in sustainable traffic and a sustainable environment.

In terms of operation, vehicles pay a charge to enter theCerchia dei Bastoni Limited Traffic Zone. The accesses to this zone are shown in Figure 4 . (Note that accesses marked in red are for exclusive use by Public Transport.)

Milan map
Figure 4: Entrance Points to the Cerchia Dei Bastioni Limited Traffic Zone


The EcoPass charges are set out in Table 7, and relate primarily to European vehicle classifications based on emissions .

Table 7: Daily and Annual Charges for Circulating within the LTZ depending on the Euro Classification of the Vehicle’s Engine.

Charge Class

Definition

Daily Charge €

Annual Pass €

Class 1

LPG, Methane, Electric and Hybrid Vehicles

Free

Free

Class 2

Euro 3 or 4 or more recent petrol cars/ Euro 4 Diesel vehicles with approved particulate filter

Free

Free

Class 3

Euro 1 and 2 petrol cars and goods vehicles

2

50

Class 4

pre Euro petrol cars and light goods vehicles/Euro 1, 2 and 3 diesel cars

5

125

Class 5

pre Euro diesel cars/pre Euro, Euro 1 and 2 diesel goods vehicles/pre Euro, Euro 1,2 and 3 mopeds and motorbikes

10

250

Note that there are no charges for mopeds and motorbikes as long as they are not defined in class 5.

Impacts on demand

After a year of the scheme implementation, the traffic reduction within the Eco Pass area was 14.4%. There was also a corresponding 3.4% reduction outside the zone.  The increase in public transport patronage entering the Cerchia Dei Bastioni LTZ over the entire period was around 6.2%.

Impacts on Supply

The Ecopass initiative was accompanied by other interventions

  • increase of bus lanes (which implies that in the absence of new capacity in Milan, there must have been a reduction in road space for general traffic)
  • increase in regulated parking zones
  • creation of new cycle routes
  • increases in public transport services connecting the 32 municpalities of the urban area to the city centre (increasing frequency between 13% to 20% depending on the line)
  • increase in metro/tram frequency by 27% during peak hours and 51% during off peak hours
Contribution to objectives
Objective Scale of Contribution Comment
  There was an increase in average speed of 4% during the peak hours which suggests a reduction in congestion and improvement in efficiency. At the same time, public transport speeds have increased by 6% (comparing the pre implementation reference value) leading to improvements in congestion related unreliability. 
  No information has been gathered on this but results of preliminary surveys indicate that up to 38% of respondents were actually in favour of expanding the LTZ ZTL. 31% of respondents would like the charge to extend to motorcycles and mopeds (which are currently exempt). Interestingly 7% actually would like to see an increase in the tariff rates.
  There has been a 14% reduction in PM10, 11% reduction in oxides of nitrogen, 9% reduction in Carbon Dioxide (comparing the pre implementation reference values with the values obtained after one year of operation i.e. comparing 2007 mean values with 2008 mean values.
 

No information was specifically gathered on this.

  There has been a decrease in total accidents of 14.4% within the Ecopass area compared to a reduction 4.6% outside the area. (comparing values pre implementation (2007) vs post implementation 2008).
  No information was specifically gathered on this but there do not seem to be any negative effects on the economy.
 

The annual revenue from tickets and passes (2008) was £12 million but the operating costs consumed around 50% of this. The net revenue is to be invested in public transport.

= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

“Sadler Street” Durham, UK

Context

Durham city is situated in North East England. It is a tourist destination, particularly for the castle and cathedral, and the fact that it is a medieval city means that its narrow city centre roads are unable to cope with high volumes of traffic. In order to manage the level of traffic entering Central Durham, local decision makers  decided to introduce charging for those vehicles wishing to access the historic core — in essence the Market Place, Cathedral and Castle, which are part of the World Heritage Site, in October 2002. (An aerial view is shown in Figure 5 below). [The core extends throughout the peninsula]

Durham map
Figure 5: Aerial View of Durham City Centre Source: Wafer (2007)

The broad aims of the charging scheme were to: improve pedestrian safety; improve access for the disabled; enhance a world heritage site; and sustain the vitality of this part of the city centre. The scheme is designed to resolve the conflict between vehicles and pedestrians when accessing the historic centre. The revenues raised have been used to support a frequent bus service to and from the charging area.
Durham’s congestion charging zone is basically a cordon- based scheme, where drivers must pay to enter a fixed zone. In fact due to the location of the peninsula, the scheme covers just one road (Saddler Street as shown in Figure 5 above), which provides access to the Market Place, Cathedral and Castle, which form Durham’s World Heritage site.

The £2 (€2.30) charge is payable on exit from the area between 10.00 to 16.00 Monday to Saturday. Exit from the area is free at all other times. Exit during the restricted period is controlled with an automatic bollard, which is linked to payment and permit detection apparatus. To exit, drivers must stop at the stop line where a red traffic signal is located alongside the payment machine. Following payment, the bollard will lower and, when fully retracted, the traffic signal will change to green and the driver can proceed safely out of the charged zone. (see Figure 6 below)

Durham street
Figure 6: Payment required on exiting from Saddler Street Source: Wafer (2007)

Drivers who fail to meet the charge will be permitted to proceed through the bollard system. However, a £30 (€34.50) charge notice is issued to the vehicle owner.  Vehicles are recorded on the CCTV system and owners traced through the DVLA (the vehicle licensing authority in the UK). Drivers attempting to avoid the charge by driving out of the uncontrolled entrance will be committing a traffic offence; and this is also monitored by the CCTV system and drivers will be fined (£30).

Impacts on demand

Results suggest that the scheme achieved an 85% reduction in vehicular traffic (from over 2000 to approximately 200 vehicles per day (Santos, 2004; Wafer, 2007)). It has been reported by businesses that the majority (83%) have not altered their servicing arrangements following the introduction of the charge, presumably they can be carried out outside controlled hours. As a result of the huge reduction in general traffic levels, vehicle emissions have dropped substantially.

Impacts on Supply

The revenues raised have been used to support a frequent bus service to and from the charging area.

Contribution to Objectives
Objective Scale of Contribution Comment
  The large reduction in traffic flows will have increased the speeds and journey times for the bus service into the centre itself. 
  There appears to have been a re-distribution from cars to pedestrians – the big fall in the number of cars appears to have been replaced by an expansion in pedestrian activity, suggesting that the area has now become a more accessible, safe and pleasant place to visit on foot.
 

The traffic reduction will have improved the environment and increased protection of the world heritage site. However there are no published results on reductions achieved.

 

No impacts have been reported.

 

There have been some bollard collisions occurring due to vehicles tailgating. Sensors on the bollard prevent the bollard from rising beneath a vehicle, however this does not prevent the  tailgating vehicle colliding with the bollard as it attempts to rise between them.

  No impacts have been reported.
 

The revenues are used to cover the costs of scheme operations and a bus service.

= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Gaps and weaknesses

The Singapore, London and Stockholm schemes, with their detailed monitoring studies, have done a great deal to improve our understanding of the performance of road user charging schemes.  However, there are still too few schemes to judge the transferability of their effects. Economic impacts are particularly unclear in centres that face competition from other conurbations in terms of shopping trips and job locations.

 

Contribution to objectives and problems
Objective Singapore Area Licensing Singapore
Electronic Road Pricing
Norwegian Toll Rings Value Pricing in San Diego London Congestion Charging
 
 
 
 
 
 
 
Contribution to objectives and problems (continued)
Objective Stockholm
Congestion Charging
Trial
Zone a Traffico
Limitato (Limited
Traffic Zones), Rome
Ecopass Milan Saddler Street,
Durham
 
 
 
 
 
 
 
= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

 

Summary of each case study's contribution to alleviation of key problems
Objective Singapore Area Licensing Singapore Electronic Road Pricing Norwegian Toll Rings Value Pricing in San Diego London Congestion Charging
Congestion-related delay
Congestion-related unreliability
Community severance
Visual intrusion
Lack of amenity
Global warming
Local air pollution
Noise
Reduction of green space
Damage to environmentally sensitive sites
Poor accessibility for those without a car and those with mobility impairments
Disproportionate disadvantaging of particular social or geographic groups
Number, severity and risk of accidents
Suppression of the potential for economic activity in the area
Summary of each case study's contribution to alleviation of key problems (continued)
Objective Stockholm Congestion Charging Zone a Traffico
Limitato (Limited Traffic Zones), Rome
Ecopass Milan Saddler Street, Durham
Congestion-related delay
Congestion-related unreliability
Community severance
Visual intrusion
Lack of amenity
Global warming
Local air pollution
Noise
Reduction of green space
Damage to environmentally sensitive sites
Poor accessibility for those without a car and those with mobility impairments
Disproportionate disadvantaging of particular social or geographic groups
Number, severity and risk of accidents
Suppression of the potential for economic activity in the area
= Weakest possible positive contribution = Strongest possible positive contribution
= Weakest possible negative contribution = Strongest possible negative contribution
= No contribution

Appropriate contexts

Urban road charging is applicable to any city. However given that there are costs associated with its implementation, it is recommended that cities considering the introduction of urban road charging should carry out a cost-benefit analysis of doing so.

Based on our above assessments, urban road charging will be particularly applicable in cities where:

  • there is an identifiable problem of traffic congestion; or
  • there has been a decision not to increase the capacity of the road network which may, without efforts to manage demand, lead to problems of traffic congestion;
  • there is (or there is scope for) a good public transport network; 
  • there is a degree of economic autonomy in relation to neighbouring cities; 
  • there is an identified need to raise revenue for particular projects.

Even within a city or town there will be contexts where urban road charging will be more or less appropriate. Appropriate area-types indicates which area-types are likely to be most and least appropriate.

Appropriate area-types
Area type Suitability
City centre
Dense inner suburb
Medium density outer suburb
Less dense outer suburb
District centre
Corridor
Small town
Tourist town
= Least suitable area type = Most suitable area type

Adverse side-effects

Planners are often concerned at the potentially adverse impact on the economy of the charged area if charging encourages drivers to travel elsewhere, there is no empirical evidence however of this having happened in London or any of the other cities where congestion charging has been implemented. However, a number of desktop and attitudinal studies have concluded that there would be minor negative economic impacts, although these are very much dependent upon the characteristics of the urban centre (e.g. Flowerdew 1994, Richards et al, 1996, Still, 1996). Most studies have highlighted the need for complementary public transport improvements.

The second concern relates to the equity implications. Bus users, pedestrians and cyclists will benefit; rail users will be little affected except, perhaps, by increased patronage, although in the longer term increased patronage may encourage an improved service. If the scheme is a mileage-based system then users of commercial vehicles that drive many miles will be disadvantaged whilst commuters may be net beneficiaries with the reduced congestion more than compensating them. If on the other hand a set daily fee is paid for unlimited mileage then it is likely that commercial drivers will benefit relative to commuters.

Links

http://www.cfit.gov.uk/docs/2006/wrrp1/index.htm

Annex 1: List of Case Studies (from http://www.cfit.gov.uk/docs/2006/wrrp1/index.htm)

References

Berg, J T, and Young, F B (1999) Value pricing helps reduce congestion, Public Roads, Vol 62 No 5, March-April 1999, Federal Highways Administration (FHWA), Washington.

CfIT’s world review of road pricing phase 1: lessons for the UK, June 2006

CURACAO (2009a) “Deliverable D2: State of the Art Review” Project: Coordination of Urban Road User Charging Organisational Issues Sponsored by European Commission under the FP6 Framework

CURACAO (2009b) “Deliverable D3: Case Study results”, Project: Coordination of Urban Road User Charging Organisational Issues Sponsored by European Commission under the FP6 Framework.

DeCorla-Souza, P (2001) Expanding the Market for Value Pricing, paper presented at the 9th World Conference on Transport Research, Seoul.

Daunfeldt S., Rudholm N., Rämme U., (2009) “Congestion charges and retail revenues: Results from the Stockholm road pricing trial”, Transportation Research Part A: Policy and Practice  43(3),306-309

Eliasson J., Hulktrans L., Nerhagen L., Smidfeld-Rosqvist L., (2009) “The Stockholm congestion-charging trial 2006: Overview of effects” Transportation Research Part A 43(3) 240-250

Eliasson J., Brundell-Freij K.,(2007) “Stockholm Congestion Charges – Forecasts and Reality” Presentation at CURACAO Seminar, Stockholm, September 25.

Holland, E.P. and Watson, P.L. (1978) Traffic restraint in Singapore. 1. Measuring the effects of the Area Licence Scheme; and 2. Some design factors in traffic pricing schemes. TEC. January 1978.

*Johansson, B. and L- G Mattsson, (1995c), (eds.) Road Pricing: Theory, Empirical Assessment and Policy, Kluwer Academic Publishers, London.

Larsen, O.I. (1988) The toll ring in Bergen: the first year of operation. Traffic Engineering and Control 29(4).

Lee, D (2000) Demand elasticities for highway travel, HERS Technical Documents, FHWA, Washington DC (http://www.fhwa.dot.gov/))

Litman, Todd (January 2006) London Congestion Pricing, Implications for Other Cities, Victoria Transport Policy Institute

May A D, Roberts M and Mason P (1992). The development of transport strategies for Edinburgh. Proc. Institution of Civil Engineers. Transport 95(1).

May, AD, Coombe, D and Travers, T (1996) The London Congestion Charging research programme 5: Assessment of the impacts. Traffic Engineering and Control 37(6)

May A. D., Shepherd S. P., Emberger G., Ash A., Zhang X. and Paulley N., (2005), “Optimal Land Use Transport Strategies: Methodology and Application to European Cities”, Transportation Research Record 1924, 129-138.

Menon, A.P.G. (2000) ERP in Singapore: a perspective one year on TEC 41(2).

*Morrison, S. A., (1986), A Survey of Road Pricing, Transportation Research 20A: 87-98.

Oldridge, B (1990) Electronic road pricing: an answer to traffic congestion? Proc Information Technology and Traffic Management. NEDO London, HMSO

Richards, M.G. et al (1996) London congestion charging research programme. 6 : the findings. TEC 37 (7/8) [also papers 1,3,5 in the series]

Supernak, J, Golob, J, Golob, T F, Kaschade, C, Kazimi, C, Schreffler, E and Steffey, D (2001) I-15 congestion pricing project monitoring and evaluation services task 13: Phase II year three overall report, San Diego Association of Governments, San Diego. As at http://www.sandag.cog.ca.us/i-15fastrak/index.html on 6 December 2001.

Stockholmsförsöket (2006a)  “Facts and Results from the Stockholm Trial: Final Report” December 2006, Available at  http://www.stockholmsforsoket.se/upload/Sammanfattningar/English/Final%20Report_The%20Stockholm%20Trial.pdf accessed December 2008.

Stockholmsförsöket (2006b) “Evaluation of the Effects of the Stockholm Trial on Road Traffic” June 2006, Available at http://www.stockholmsforsoket.se/upload/Rapporter/Trafik/Under/Effects%20of%20the%20Stockholm%20Trial%20on%20road%20traffic.pdf accessed December 2008.

Transek (2006) “Equity Effects of the Stockholm Trial” Available at: http://www.stockholmsforsoket.se/upload/Sammanfattningar/English/Equity Effects of the Stockholm Trial.pdf

Transport for London (various years), Central London Congestion Charging Impacts Monitoring, Annual Report, see http://www.tfl.gov.uk/roadusers/congestioncharging/6722.aspx for details

*Walters, A. A., (1968), The Economics of Road User Charges, World Bank Occasional Paper No. 5, International Bank for Reconstruction and Development, Johns Hopkins University Press, Baltimore, Maryland.

Wilson, P.W. (1988) Welfare effects of congestion pricing in Singapore. Transportation 15(3).

Santos G., (2004) “Urban Road Pricing in the UK”, in Santos G (eds) Road Pricing: Theory and Evidence, Research in Transportation Economics 9 Amsterdam: Elsevier, 251-282.

Value pricing home page:
http://www.hhh.umn.edu/centers/slp/conpric/conpric.htm

Wafer D., (2007) “Transport Innovation in a Historic City”, Presentation the Joint Independent Transport Commission/CURACAO Seminar, London, 22 March

* denotes items which are not referred to specifically but which might form useful additional source