“Transport decisions are about values”: Australia shows the limitations of cost-benefit analysis

The Gold Coast light rail. Image: David Ansen/Flickr/creative commons.

Growing the economy – not city planning – has become the Australian government’s main rationale for building urban transport infrastructure. Soon after becoming prime minister in September 2015, Malcolm Turnbull declared: “I will be an infrastructure prime minister”.

Subsequently, his government’s focus seems to be largely on infrastructure projects – including urban transport infrastructure – “which drive … growth and jobs”.

Transport infrastructure is seen as a facilitator of growth and competitiveness in our cities. This is where much of Australia’s economic growth is generated. But, while important, promoting economic growth is not transport’s only major function.

Increasingly divorced from city planning

Until recently, it was generally accepted that urban transport and land development needed to be planned in an integrated way, having regard to what city future was desired. Transport infrastructure investment would then help to achieve that city future.

While city planning was once a “tool for correcting and avoiding market failure”, it is now much more about promoting economic growth by providing certainty for the development industry and reducing regulation.

Under this increasingly dominant view, city planning (by governments) is seen as a generally distorting influence on property markets. Regulation is a “transaction cost”.

Major urban transport investment is increasingly divorced from achieving broader city planning objectives. This includes equitable access to services and facilities.

For example, there is a disconnect between the TransApex major road program and urban planning in southeast Queensland. This program of four major road projects in Brisbane aimed to improve cross-city travel and keep the economy strong. However, TransApex was at odds with the southeast Queensland regional plan’s aim of promoting sustainability and reducing car dependency.

Cost-benefit analysis is preferred

Instead of an integrated city planning approach, governments are increasingly basing transport investment decisions on cost-benefit analyses.

Cost-benefit analysis for transport projects involves weighing up the costs (construction and operating costs) and benefits (travel time savings, vehicle operating cost savings, crash cost savings and wider economic benefits). If the dollar value of the benefits exceeds the costs, the project is considered justified.

It has recently been suggested that all transport projects where benefits exceed costs by some margin should be built, apparently with little regard to the effects of those projects on city planning.

The significant limitations of cost-benefit analyses are well documented. It is particularly troubling that, for transport projects, these analyses rely on a flawed assumption that motorists aim to minimise generalised costs.

Cost-benefit analyses also provide limited guidance in deciding which projects advance broader city planning objectives.


Transport decisions are about values

Decisions about transport investments are really about what kind of future city we desire.

These are decisions about values as much as they are about economics. American philosopher Michael Sandel is concerned that conversations about the future are largely framed in technocratic (often economic) terms. This leaves public discourse “hollowed out”.

The social equity effects of transport investment are not usually taken into account. The public investment of about A$1bn in the Gold Coast light rail disproportionately benefits residents, landowners and businesses close to the stations. Other Gold Coast residents – including many disadvantaged people – have to drive or make do with a relatively low-quality bus service.

With cities now urged to market themselves, “flagship” projects like the light rail are valued as means of giving cities an advantage in a world of footloose businesses and investors. These projects are considered important for growing the economy.

The Gold Coast light rail is an 18-year public-private partnership (PPP). PPP contracts frequently include “non-compete” clauses (no new competition with the PPP infrastructure). These can constrain future city planning decisions, however desirable they may be.

Splintered development is poor planning

The influence of cost-benefit analysis, city marketing and PPPs works against an integrated approach to land use and transport planning.

This situation can be described as “splintered” infrastructure development and raises questions about its impacts on the achievement of broader city planning objectives. While individual infrastructure investments with a positive benefit-cost ratio may help grow the economy, the idea that this will trickle down to better social or environmental outcomes for city residents is problematic.

It doesn’t have to be like this. One policy proposal for Adelaide offers examples of how transport and land use can be better integrated to support an overall city vision.

New transport infrastructure will clearly be needed in Australia’s growing capital cities just to maintain current levels of accessibility. There will be plenty of scope for Turnbull to leave a legacy of transport infrastructure that not only helps grow the economy but also supports integrated city planning.The Conversation

Brian Feeney is an urban planning researcher at The University of Queensland.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

How bad is the air pollution on the average subway network?

The New York Subway. Image: Getty.

Four more major Indian cities will soon have their own metro lines, the country’s government has announced. On the other side of the Himalayas, Shanghai is building its 14th subway line, set to open in 2020, adding 38.5 km and 32 stations to the world’s largest subway network. And New Yorkers can finally enjoy their Second Avenue Subway line after waiting for almost 100 years for it to arrive.

In Europe alone, commuters in more than 60 cities use rail subways. Internationally, more than 120m people commute by them every day. We count around 4.8m riders per day in London, 5.3m in Paris, 6.8m in Tokyo, 9.7m in Moscow and 10m in Beijing.

Subways are vital for commuting in crowded cities, something that will become more and more important over time – according to a United Nations 2014 report, half of the world’s population is now urban. They can also play a part in reducing outdoor air pollution in large metropolises by helping to reduce motor-vehicle use.

Large amounts of breathable particles (particulate matter, or PM) and nitrogen dioxide (NO2), produced in part by industrial emissions and road traffic, are responsible for shortening the lifespans of city dwellers. Public transportation systems such as subways have thus seemed like a solution to reduce air pollution in the urban environment.

But what is the air like that we breathe underground, on the rail platforms and inside trains?

Mixed air quality

Over the last decade, several pioneering studies have monitored subway air quality across a range of cities in Europe, Asia and the Americas. The database is incomplete, but is growing and is already valuable.

Subway, Tokyo, 2016. Image: Mildiou/Flickr/creative commons.

For example, comparing air quality on subway, bus, tram and walking journeys from the same origin to the same destination in Barcelona, revealed that subway air had higher levels of air pollution than in trams or walking in the street, but slightly lower than those in buses. Similar lower values for subway environments compared to other public transport modes have been demonstrated by studies in Hong Kong, Mexico City, Istanbul and Santiago de Chile.

Of wheels and brakes

Such differences have been attributed to different wheel materials and braking mechanisms, as well as to variations in ventilation and air conditioning systems, but may also relate to differences in measurement campaign protocols and choice of sampling sites.

Second Avenue Subway in the making, New York, 2013. Image: MTA Capital Construction/Rehema Trimiew/Wikimedia Commons.

Key factors influencing subway air pollution will include station depth, date of construction, type of ventilation (natural/air conditioning), types of brakes (electromagnetic or conventional brake pads) and wheels (rubber or steel) used on the trains, train frequency and more recently the presence or absence of platform screen-door systems.

In particular, much subway particulate matter is sourced from moving train parts such as wheels and brake pads, as well as from the steel rails and power-supply materials, making the particles dominantly iron-containing.


To date, there is no clear epidemiological indication of abnormal health effects on underground workers and commuters. New York subway workers have been exposed to such air without significant observed impacts on their health, and no increased risk of lung cancer was found among subway train drivers in the Stockholm subway system.

But a note of caution is struck by the observations of scholars who found that employees working on the platforms of Stockholm underground, where PM concentrations were greatest, tended to have higher levels of risk markers for cardiovascular disease than ticket sellers and train drivers.

The dominantly ferrous particles are mixed with particles from a range of other sources, including rock ballast from the track, biological aerosols (such as bacteria and viruses), and air from the outdoors, and driven through the tunnel system on turbulent air currents generated by the trains themselves and ventilation systems.

Comparing platforms

The most extensive measurement programme on subway platforms to date has been carried out in the Barcelona subway system, where 30 stations with differing designs were studied under the frame of IMPROVE LIFE project with additional support from the AXA Research Fund.

It reveals substantial variations in particle-matter concentrations. The stations with just a single tunnel with one rail track separated from the platform by glass barrier systems showed on average half the concentration of such particles in comparison with conventional stations, which have no barrier between the platform and tracks. The use of air-conditioning has been shown to produce lower particle-matter concentrations inside carriages.

In trains where it is possible to open the windows, such as in Athens, concentrations can be shown generally to increase inside the train when passing through tunnels and more specifically when the train enters the tunnel at high speed.

According to their construction material, you may breath different kind of particles on various platforms worldwide. Image: London Tube/Wikimedia Commons.

Monitoring stations

Although there are no existing legal controls on air quality in the subway environment, research should be moving towards realistic methods of mitigating particle pollution. Our experience in the Barcelona subway system, with its considerable range of different station designs and operating ventilation systems, is that each platform has its own specific atmospheric micro environment.

To design solutions, one will need to take into account local conditions of each station. Only then can researchers assess the influences of pollution generated from moving train parts.

The ConversationSuch research is still growing and will increase as subway operating companies are now more aware about how cleaner air leads directly to better health for city commuters.

Fulvio Amato is a tenured scientist at the Spanish National Research CouncilTeresa Moreno is a tenured scientist at the Institute of Environmental Assessment and Water Research (IDAEA), Spanish Scientific Research Council CSIC.

This article was originally published on The Conversation. Read the original article.