The National Infrastructure Commission has sought evidence on how the deployment of intelligent traffic systems could help optimise the road network. I sent a response, found here Metz NIC traffic management 1-9-17

My argument is that we need to move beyond traffic management using traffic signals to management involving collaboration between public sector road authorities and the private sector suppliers of digital maps and route guidance apps, such as Google Maps and Waze. These apps have become very popular for turn-by-turn route guidance that can take account of, and help avoid, traffic congestion and provide estimates of journey time before setting out. These features help tackle the main problem of traffic congestion which is journey time uncertainty.

I would expect that collaboration between public and private sectors would improve both the experience for road users and the efficiency of network operations.

In late July the Government published its Plan for tackling roadside nitrogen dioxide (NO2) concentrations, to reduce these below the statutory limit. Publication was met by considerable criticism that the Plan lacked urgency and effectively dumped the problem on the most affected local authorities, which would be required to implement Clean Air Zones (CAZ).

An accompanying 155-page Technical Report included, on its final page, new estimates of the economic benefits from reducing damage to health through measures to reduce NO2. Remarkably, these new estimates were very substantially below those that had been published in the Technical Report of May 2017  that accompanied the consultation preceding the Plan. For instance, the previous estimated health benefit of a further 21 CAZs was £3.6bn, but now is £620m – an 80% reduction.

This huge reduction was attributed to new advice from the independent experts of the Committee on the Medical Effects of Air Pollution (COMEAP), which had found it difficult to disentangle the impacts of specific pollutants, in this case NO2, from that of the whole mix of traffic related pollutants.

COMEAP’s previous advice recommended a central coefficient of 1.025 per 10ug/m3 NO2, which means that for every 10ug/m3 increase in NO2 concentration, the increase in mortality risk would be 2.5%. The revised advice now recommends a coefficient of 1.023 for traffic-related pollution; but COMEAP also recommends that when measures are primarily targeting NO2 emissions this coefficient should be adjusted to account for possible overlap between the direct impacts of small particulates and NO2. Applying their recommended adjustment, the resulting coefficient used for the analysis is 1.0092.

My enquiries of the Government’s Joint Air Quality Unit elicited the confirmation that overall the updated NO2 damage costs for road transport are approximately 80% lower than those used at consultation. This splits into roughly 60-65% resulting from the revised COMEAP advice and the remaining c.15-20% resulting from the other updates such as new dispersion modelling and population data. The JAQU confirmed that the reduction in the road transport NO2 damage cost primarily reflects a reduction in the estimated mortality impact associated with NO2 alone.

There has been widespread interest and concern about the health impacts of roadside air pollution over the past year and more. So it is surprising to learn of such a substantial downward revisions of official estimates of health impact. However, the relevance for policy is as yet unclear.

Current policy is driven by the need to avoid exceeding statutory limits for NO2 concentration laid down in a EU Directive that applies uniformly to all regions of the Community, in which context the scale of health benefits from remedial measures is not relevant. However, Britain is to leave the EU, which may open the possibility of regulation of air quality based on UK targets set to reflect the balance of benefits in relation to costs. A down rating of health benefits would then be relevant, particularly given the expected reductions in pollutants from improved vehicle technology and from the introduction of electric propulsion. Whether the Government would be willing to propose targets to reflect UK conditions remains to be seen – it may depend on the outcome of the Brexit negotiations and on a judgement about the politics of air pollution.

 

A version of this post was published in The Conversation on 30 August 2017

https://theconversation.com/no-not-as-bad-as-we-thought-83056

 

 

 

 

 

 

The Department for Transport publishes passenger numbers for the English light rail systems, shown in the Figure. What is striking is the very different growth rates: buoyant for London’s Docklands Light Rail and Tramlink, and for the systems in Manchester and Nottingham; but relatively static elsewhere – West Midlands, Sheffield and Tyne & Wear.

Urban light rail offers speedy and reliable travel compared to cars and buses on congested roads. In a growing economy, we expect its popularity to grow, as we see in London and Manchester.

The light rail passenger number trends bear upon the general question of whether transport investment can foster economic growth, or whether it follows it. The different patterns observed tends to suggest that urban rail investment can contribute to existing economic growth but may not in itself stimuate lift-off.

It is conventional to value transport investments by estimating the time savings to users, which are multiplied by a value of time derived from Stated Preference studies, essentially survey questions that ask people to trade off time against money. A major re-estimation of the value of travel time commissioned by the Department for Transport prompted me to review the appropriateness of this methodology.

I have long been concerned with the use of travel times savings. The National Travel Survey shows that average travel time has not changed over the past 40 years, during which period many £billions have been invested in the transport system, based on the supposed value of time savings. The NTS findings show that there are no time savings in the long run, the relevant perspective for investment in long-lived infrastructure. The real benefit of such investment is to improve access to land that can be developed to accommodate a growing population and boost the economy. A good example is the regeneration of London’s Docklands made possible by rail investments. So we need an approach to investment appraisal that focuses on the spatial impact, given that the outcome is additional movement of people and goods through space.

I have a paper just published on this topic. Get in touch if you have difficulty in accessing the full paper david.metz@ucl.ac.uk

Lord Wolfson offered a prize worth £250,00 for the best proposal in response to the question: ‘How can we pay for better, safer, more reliable roads in a way that is fair to road users and good for the economy and the environment’.

The winner was Gergely Raccuja, a recent UCL graduate, now a transport planner with Amey Consulting. His proposal has the merit of simplicity: replace Fuel Duty and Vehicle Excise Duty, receipts from which are declining as vehicles become more fuel-efficient, with a per-mile charge that would depend on a vehicle’s weight (reflecting the damage caused to the road) and emissions (damage to the environment). The charge would be collected by the insurance companies, the new charge being in effect a supplement to the insurance premium.

The impact of congestion caused by a vehicle is captured in a crude way by a distance-related charge. However, the opportunity to relate the charge to the level of congestion was not taken because of the perception that it would be unpopular and hence prevent the new charging scheme being adopted.

Some of the other finalists for the prize proposed schemes involving charging that reflected in part the contribution of vehicle users to congestion, but these were not favoured by the judges.

Assessment

It is very welcome that a new entrant to the transport planning profession was the prize winner, with a relatively simple proposal. But is it likely to be taken up? My sense is that implementation would not be seen as worth the effort and upheaval. Perhaps the main advantage is that electric vehicles would contribute to the costs of the road system, but for that purpose the proposal might be applied to EVs only, leaving Fuel Duty in place for vehicles with internal combustion engines.

The main shortcoming of the prize-winning proposal is the failure to address the problem of road traffic congestion and how it might be mitigated by charging. Public perceptions are important, of course, but I found it odd that there is no mention of London congestion charging, which has proved quite acceptable.

Any change to how we pay for roads should take the opportunity to ameliorate road traffic congestion, which is the biggest problem of the transport system. Arguably, the question set for the prize was misconceived, with its opening emphasis on ‘How can we pay for….’. It might have been better to ask ‘How can we achieve better, safer, more reliable roads….’

 

There is considerable interest in, and support for diesel scrappage schemes. The challenge is to target polluting vehicles making the biggest contribution to poor air quality. In my recent blog on air quality, I said that it would be hard to devise a scrappage scheme for the more polluting diesel vehicles. On reflection, I can see a way forward.

The Mayor of London has advocated a national diesel scrappage fund. Transport for London has developed detailed proposals that involve targeting small businesses, charities, schools, low-income households and the oldest taxis, at a total cost for London of some £500m. The recent Defra/DfT Technical Report on reducing NO2 levels considers a national diesel scrappage scheme aimed at all pre-Euro 6 diesel cars and vans, and also a scheme to replace non-compliant vehicles with battery electric vehicles. The former is extremely expensive, while the latter makes very limited impact.

I propose that a scrappage scheme could be integral to the  Ultra Low Emission Zone (ULEZ) proposed for London, which would naturally target the vehicles making the greatest contribution to poor air quality.

The ULEZ will generate net revenue that could be used to fund a scrappage scheme. The targeted vehicles would be those that pay the largest cumulative charges for entry into the zone, since these make the greatest impact on air quality. The formula might be a contribution of £X00 to scrappage for every £1000 of cumulative charges – a cash-back offer. The value of X could be adjusted in the light of experience of uptake.

Owners scrapping a car or van under the scheme would need to provide evidence that the vehicle had been scrapped. To discourage replacement by a further polluting vehicle, it might be a condition of the scrappage scheme that the owner would not be allowed in future to pay the standard charge for entry of a non-compliant vehicle into the ULEZ, and would therefore incur the penalty charge should this be done.

Over time, as non-compliant vehicles are scrapped, revenue from the ULEZ would fall, as would NO2 levels. Depending on how far the latter was from the statutory limit, the scope of the zone could be extended, whether to more recent vehicles or to a wider geographic area.

I suggest that TfL considers in detail how a scrappage scheme might work as part of a the ULEZ, and what incentives might be sought from the Government to adopt such arrangements.

The Government recently published its latest draft Air Quality Plan for reducing nitrogen dioxide (NO2) in towns and cities. This followed loss of a court case in which the previous Plan was found wanting, particularly by not fully recognising the poor on-the-road emission performance of diesel cars, despite their seeming compliance with regulatory requirements in laboratory tests. This latest Plan has been criticised as inadequate by many protagonists and press commentators.

Nevertheless, the new draft Plan and accompanying Technical Report represent a significant advance analytically, being based on systematic review of options, assessed using multi-criteria analysis and cost-benefit analysis. Impacts include health benefits, social and government costs, time savings from improved traffic flow, and change in greenhouse gas emissions.

The starting point is that road transport is by far the largest contributor to NO2 pollution in the 40 local authorities in England where the statutory limit values are exceeded. London has much the highest level – mean annual concentration in excess of 100 μg/m3, compared with the statutory limit of 40 μg/m3.

The most cost-effective – indeed the only worthwhile – approach to mitigation is through establishing Clean Air Zones (CAZs) where targeted action is taken. The 2015 Plan proposed CAZs in London and 5 other cities. This 2017 Plan extends coverage to 27 in all, reflecting updated assumptions about diesel emissions.

A key issue is whether a CAZ should require that the more polluting vehicles be charged for entry. For locations where NO2 levels are only modestly in excess of the legal limit, measures other than charging may suffice. Nevertheless, the Technical Report models the impact of charging in all 27 cities, which would involve set-up costs of £270m. For 12 of these, charging could be limited to public service and goods vehicles, but for 15 it would need to extend to cars not compliant with the latest Euro 6 diesel standard. The main impact of charging is assumed to be a two-thirds reduction of trips by non-compliant cars. A charging CAZ is projected to result in an 18% reduction in NO2 levels in the first year of impact.

A variety of other measures to reduce NO2 levels are considered in the Report. One approach that has attracted much support is for a scheme to offer payments to owners to scrap older polluting vehicles. The Report states that a national scheme to scrap all pre-Euro 6 diesel cars and vans could cost £60 billion. A scheme limited to replacement by battery electric vehicles assumes that only 15,000 vehicles would be scrapped.

The Report does not consider targeting by area, for which London would have a strong case for funding given the high NO2 levels, although this would be politically contentious. High mileage polluting vehicles would be the target. However, the difficulty is that the oldest vehicles tend to be both most polluting per distance travelled but least used, and owned by low-income households for whom the cash incentive would need to be high. So a well-targeted scrappage scheme seems hard to devise.

Transport for London is consulting on an Ultra Low Emission Zone (ULEZ) – effectively a charging CAZ – to cover the same area as the Congestion Charge. Non-compliant cars and vans will be charged £12.50 a day, which will apply 24/7 from April 2019. This is in addition to an emissions surcharge on top of the congestion charge for pre-Euro 4 cars and vans of £10 from October 2017. There is also a London-wide Low Emissions Zone in operation since 2008 that charges polluting heavy diesel vehicles.

On introduction, the ULEZ is projected to reduce the proportion of road kilometres exceeding limit NO2 values in Central London from 82% to 70% – a moderate air quality benefit but far from sufficient. This suggests that the charge and/or scope may need to be increased in future.

Introducing the ULEZ is relatively easy in London, given the existing of the Congestion Charge arrangements for payment and enforcement. Other cities needing to adopt a charging CAZ could adopt the technology used by London, in which case it would be natural to use it for congestion charging, both to manage peak demand and to raise revenue for investment in local transport. If 27 cities have such arrangements, this constitutes the nucleus of a national road user charging framework, which could be used to raise revenue for the road system as electric vehicles gradually take over, given that these do not pay fuel duty. The Government’s ambition is for all new cars and vans to be zero emission by 2040, and for nearly every car and van to be zero emission by 2050.

Seeing charging CAZs as a precursor to general road pricing would be contentious. This may be why the Government wished to delay publishing its draft Air Quality Plan until after the election, and why in the published consultation document the Government has been coy about charging, stating: ‘The Government believes that charging zones should only be used where local authorities fail to identify equally effective alternatives.’ The analysis presented suggests that the alternatives are unlikely to be sufficient.

The present objective is to reduce NO2 emissions to below the statutory limits specified in the EU air quality directive. However, Britain is to leave the EU, which may open other possible approaches, for instance setting policy targets expected to be achievable with available technologies and resources, balancing benefits against costs. In the long run, the problem of transport NO2 emissions will be solved by switching to electric vehicles – which arguably should be the policy priority.

This blog is the basis for a Viewpoint article in Local Transport Today of 26 May 2017.

 

 

 

 

 

 

 

 

 

Most air travel forecasts predict a long-term rise in demand, with limited consideration of any limits to growth. However for any given population there will be those who have not flown recently, as well as those who never have flown. For the UK, about half the population respond to travel surveys that they did not fly in the previous 12 months. We call these the ‘infrequent flyers’.

Little is known about this group, including  whether they are likely to fly in the future. Anne Graham, of the University of Westminster, and I recently published findings of an analysis of the characteristics of this group and the reasons for their travel habits, using a survey commissioned by the UK Civil Aviation Authority. We found that infrequent flyers make up a heterogeneous consumer group whose non-flying is influenced more by budget constraints and personal circumstances than specific aviation factors such as fear of flying.

The proportion of infrequent flyers in the UK population has remained stable over time. Our findings do not suggest that this is likely to change in the future, so the infrequent flyers are unlikely to be a source of future demand for air travel on account of their increased propensity to fly.

Our paper: Graham&Metz JATM Infreq flyers published

I have for some time taken issue with the way the UK Department for Transport (DfT) plays down the economic benefits of land and property development that result when new transport investment makes land more accessible. While DfT recognises that housing developments may be dependent on provision of new transport services, the associated economic benefit is not included in the estimation of the benefit:cost ratio that determines the value for money of the transport investment.

The Department for Communities and Local Government (DCLG) recently published its Appraisal Guide.  This states (para 3.9):

‘….changes in land values as a result of a change in land-use for a development reflect the economic efficiency benefits of converting land into a more productive use. Land value data should be the primary means of assessing the benefits of a development. Land value data is a rich source of information because it is actual market data on individuals’/firms’ willingness to pay for a piece of land. Assuming individuals and firms are rational in their decision-making, market prices should reveal the ‘true’ private benefit of a development. This information can be used to undertake cost benefit analysis to quantify the potential welfare implications of a development.’
So there is a marked difference in the way two government departments treat land value uplift in economic appraisal, which is pretty odd. My view is that DCLG has the right idea. DfT is wedded to a theoretical framework that focuses on benefits to users of the transport system, and assumes that land use is unchanged. But this flies in the face of extensive evidence that transport investment that makes land more accessible can trigger development – London’s Docklands is a prime example of rail investment making land accessible for development. DfT should adopt an evidence-based approach, using evidence of outcomes from completed investments to inform the case for prospective investments.

The current main method of adding capacity to UK motorways is known as Smart Motorway All Lane Running. This involves allowing traffic to use the hard shoulder (previously reserved for breakdowns), with speed controls to respond to accidents and congested conditions. This approach has been applied to a section of the M25, London’s orbital motorway, increasing running lanes from 3 to 4. A monitoring report after two years of operation has been published. The main findings, compared with before the scheme was introduced: traffic flows up by as much as 17%, well above the regional trend (5%); some journey times increased by up to 8%; and only a slight improvement in reliability. Significantly, the biggest increases in traffic occurred at weekends (as much as 26%).

Assessment

The intention of investment to increase the capacity of the Strategic Road Network, of which the M25 forms an important part, is to improve connectivity between cities and reduce congestion. However, roads like the M25, that are located in densely populated areas, are also used by local users for their daily travel. Any increase in capacity offers opportunities for more or longer local trips.The resulting extra traffic restore congestion to that it had been prior the the investment in capacity. The findings of the present study are consistent with this general experience. Regrettably, there is no data on the composition of the traffic, by journey purpose or distance travelled. However, the finding of a big increase in weekend traffic is consistent with leisure users taking advantage of initially faster travel to reach more distant destinations.

The findings of this report confirm the phenomenon of ‘induced traffic’ – the traffic that results from additional road capacity – as I discussed recently in connection with the CPRE study. Such traffic adds to congestion and so reduces the time savings expected from such investment, time savings that constitute the main economic benefits presumed to justify the investment.