The Singapore Area Licence Scheme

Context

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

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

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.

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

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.

Impacts on demand

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

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

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

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

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.

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)         

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)    

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.

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

Note that powered two wheelers are exempt from the charge.

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

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

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

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).

“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 the Cerchia 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.)

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.

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.

“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]

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)

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.

Gaps and weaknesses