Traffic management explained

(HT: Atlantic Cities)

Bicycle usage in Indian cities

The Muncipal Corporations of Vijayawada and Visakhapatnam are promoting bicycle use in an effort to reduce vehicular pollution and traffic congestion. Visakhapatnam has apparently introduced 'no motor vehicle' zones across 20 km of roads and plans to earmark cycling tracks on 100-feet roads to a width of about 8 feet in the central parts of the city. While these are laudable social and communitarian initiatives, its economic, and even environmental, benefits are questionable.

Here are a few observations

1. Bicycle use can reduce pollution and traffic congestion only if they displace other modes of transport in significant numbers. It is inconceivable, given Indian conditions, that car users will switch to bicycles, except maybe in small enclaves. Given the large commute distances involved, motorbike users are also likely to stay on with their vehicles. The sheer volume of road users in the larger Indian cities means that the impact on public transport due to bicycle users may be minimal.

2. While bicycles will certainly take that many people away from public transport (and to that extent reduce the demand for public transport), I am not sure whether it necessarily reduces traffic congestion nor is economically more efficient. For sure bicycles do not suffer from carbon emissions. But they take up more road space than public transport. If you have any doubt see this. Further, since bicycle commuters spend more time on roads than those using public transport over the same distance, the effective road space usage by bicycle users is much larger.

3. It is on grounds of economic efficiency that bicycles fail most glaringly, especially for Indian conditions. Most of the larger Indian cities are pretty expansive compared to the mid-sized European cities where bicycles are popular. Average commute distances are large enough to make bicycling unattractive. Weather is pretty harsh for most part of the year. In the circumstances, commuting to work, as opposed to taking public transport, increases the unproductive time spent on the road and takes its toll on productivity.

4. Earmarked bicycle lanes involve a trade-off on road space. That much road space becomes unavailable for all the other modes of transport. Any such earmarking can be effective only if we are able to displace enough motor vehicles (by making them switch over to bicycles) to make up for the loss in road space to bicycle lanes. However, as the aforementioned arguements suggest, this may not happen. In any case, given that most roads are narrow in our cities, it may not be practical to do such ear-marking in any meaningful scale.

In fact, if all the aforementioned assumptions hold true, then earmarked bicycle lanes would end up worsening traffic congestion. The effective road space usage per commuter will be higher with bicycle users. Average speeds will be reduced and fuel consumption will increase. Contrary to conventional wisdom, vehicular pollution will increase.

5. Bicycle lanes and promotional activities cannot succeed in a piecemeal manner over small road stretches. If the commuter has to travel the major length of his daily commute to work on mixed traffic, the marginal utility of any limited earmarking is likely to be minimal. However, it is possible that there are small stretches or surroundings which enclose both people's homes and their workplaces.

6. There is also the issue of traffic discipline and enforceability of bicycle lanes. In a country where regular motor vehicle lane driving and traffic discipline is the exception than norm, it may be a nightmare to enforce bicycle lanes. Unless there are physical barriers, it may not be possible to even keep motor vehicles out of these lanes. Similar lack of discipline among bicycle users could end up increasing accidents and lowering traffic speeds.

7. Finally, bicycle promotional policies should not be confused with pedestrianization programs. There is a compelling case for making certain areas, especially commercial and shopping centers, in many cities "motor vehicle free zones" for certain time periods daily, atleast during the night. Similar restrictions can be imposed on river and seaside roads so as to improve the quality of leisure environments. Bicycle usage promotion could go hand in hand with such pedestrianization programs. However, such programs are most likely to be predominantly pedestrianization programs where bicycle usage happens to be an incidental benefit.

I strongly believe that urban policy makers should instead spend their scarce energies and resources on improving transport infrastructure and public transport facilities.

The future of urban management - smart cities

The Times has a nice article that chronicles IBM's experiment in Rio di Janeiro to reshape the future of urban management,

City employees in white jumpsuits work quietly in front of a giant wall of screens — a sort of virtual Rio, rendered in real time. Video streams in from subway stations and major intersections. A sophisticated weather program predicts rainfall across the city. A map glows with the locations of car accidents, power failures and other problems.

As the Times article writes, it is increasingly possible to use powerful data analytics software to forecast trends and thereby provide decision-support on various issues of urban management. This is expected to help decision makers anticipate, instead of react, problems and plan accordingly to either avoid them or to atleast minimize the damage (or derive more benefit) from them.

Many metropolitan areas already use data-collection systems like sensors, video cameras and GPS devices. But advances in computing power and data analysis now make it possible for companies like IBM to collate all this data and, using computer algorithms, to identify patterns and trends.

IBM is the master integrator who co-ordinates the functions of all other partners,

Local companies handled construction and telecommunications. Cisco provided network infrastructure and the videoconferencing system that links the operations center to the mayor’s house. The digital screens are from Samsung. IBM coordinated everything... IBM incorporated its hardware, software, analytics and research. It created manuals so that the center’s employees could classify problems into four categories: events, incidents, emergencies and crises. A loud party, for instance, is an event. People beating up each other at a party is an incident. A party that becomes a riot is an emergency. If someone dies in the riot, it’s a crisis. The manuals also lay out step-by-step procedures for how departments should handle pressing situations like floods and rockslides...

IBM also installed a virtual operations platform that acts as a Web-based clearinghouse, integrating information that comes in via phone, radio, e-mail and text message. When city employees log on, they can enter information from, say, an accident scene, or see how many ambulances have been dispatched. They can also analyze historical information to determine, for instance, where car accidents tend to occur. In addition, IBM developed a custom flood forecast system for the city... The project cost Rio about $14 million. If it all works according to plan, it could make Rio a model of data-driven city management.

I have a few cursory observations. Apart from the prohibitive cost, many of these technologies, especially the integration of different systems and the development of data analytics that can serve as effective decision-support, are at the initial stages of its evolution. It is therefore to be expected that it will be sometime before the IBM's Intelligent Operations Center catches on and gets scaled up elsewhere.

However, there are several low-hanging fruits in this eco-system. They are low-hanging not only because they can be implemented with limited investments but also would significantly enhance the effectiveness of urban administration and/or improve the quality of life for citizens.

For example, intelligent traffic management systems, which integrate the feeds from all existing hardware - cameras, signal lights, GPS devices in various vehicles, wireless and other police communication systems etc - can be a powerful force multiplier in traffic management. Mobile phone communication signals can be used to map real-time traffic intensity on various city roads (including short-term traffic trends) and the same can be rendered on mobile phone apps to enable commuters to plan their travel more smartly. Similar applications can crowdsource information about utilities related complaints; achieve energy efficiency in all types of lighting and water and sewerage utility motor pumps; cognitively striking data visualization can enhance decision-support systems available for municipal officials, and so on.

Like any new technology, the breakthroughs will come once citizens and urban administrators realize the effectiveness of these systems and the large impact they make on their lives and activities. Given the high cost and nascent technology options, a few quick-wins are necessary to break open this market.

See this and this from IBM and Cisco respectively.

The benefits of congestion pricing illustrated

Excellent videos from Streetsblog on congestion pricing...



... and its fairness.



Usage and vehicle-type based road tolling for trucks in Germany...



Would be great to have such videos for other social and civic issues!

Infographic of the year - Time Maps!

I am a strong believer in the use of graphic visualizations as decision support and to increase workplace productivity. Fast Company has a link to its selected 22 infographics of the year. The one that really stands out for me is the TimeMap created by Vincent Meertens.

TIMEMAPS from graphsic on Vimeo.

TimeMap is a visualization aimed at commuters that maps locations based on the time taken to travel to them from a particular location. It is dynamic and the shape of the map varies in response to changes in traffic and travel options. The currently available web version of TimeMap plots train travel times across Netherlands.

Load TimeMaps from anywhere in the country, and it automatically checks your location, shows the nearest train station, and charts trip times around the country in rings, with each colored ring representing another 30 minutes. Most importantly, the map is live. It grows and shrinks throughout the day, as travel times themselves grow and shrink; the bigger the map, the longer it’ll take you to get around... the map expands at night, when trains run infrequently or not at all, then contracts during the day, when trains run on their regular, zippy schedule. Track delays? The map grows again.

TimeMaps can be useful to generate maps for air and road travel times. One option would be to integrate mobile phone traffic data into the TimeMap application and generate real-time maps of traffic conditions and travel options in any city. Characteristics of the mobile phone data can be used to identify those used by road users and its mobility patterns can give information about road traffic conditions.

Such cognitively salient data visualization can provide excellent decision support for road users and help everyone optimize their travel times and thereby minimize traffic problems. The real-time nature of the information and its availability in the simplest form to its consumers will help them use it optimally and thereby generate the most efficient traffic outcomes.

Such visualization tools become potent traffic force multipliers in cities where commuters have multiple travel options. For example, the presence of good public transit system helps commuters effectively switch across different travel modes and travel routes to make their daily peak-hour travel decisions in a manner that would contribute towards optimizing traffic patterns.

The case for public transport!

The case for public transport (or bicycle use) needs no explanation!



(HT: Green Blog)

Incentivizing efficient road usage - per kilometer driving tax?

Arguably the biggest challenge with traffic management in coming years would be the issue of managing demand response among private vehicle users. Congestion tax, road toll, vehicle miles travelled tax, and so on are being experimented in different cities across the world.



In this context, Times points to an experimental six-month road pricing trial conducted in Eindhoven, where a few cars were outfitted with a meter, hooked to wireless internet and a GPS, that would inform drivers in real-time of a road fee which is calculated based on the vehicles fuel efficiency, miles driven, time of road use, and the route being used. The fee is a measure of the cost to the society in the form of pollution, traffic congestion, greenhouse gas emissions and wear and tear on roads. At the end of each month, the vehicle’s owner would receive a bill detailing times and costs of usage, not unlike a cellphone bill.



The trial, which logged more than 200,000 test kilometers, showed that with the help of technology, drivers can be motivated to change their driving behavior, reducing traffic congestion and contributing to a greener environment. Its findings include,

"70% of drivers improved their driving behavior by avoiding rush-hour traffic and using highways instead of local roads. On average, these drivers in the trial saw an improvement of more than 16% in average cost per kilometer... Instant feedback provided via an On-Board Unit display on the price of the road chosen and total charges for the trip is essential to maximizing the change in behavior."

The Netherlands is debating the introduction of a new road-use charge, per-kilometer driving tax, starting in 2012 for trucks and lorries, and 2013 for passenger cars, and become nation-wide by 2016. Its objective is to reduce traffic delays and CO2 emissions and lower private vehicles road use and increase public transit use. The government was to reduce or even eliminate conventional taxes on vehicle purchases and registration and replace them with a single per-kilometer driving tax. However, political considerations have forced these plans to be atleast delayed.

Parking charges across cities

Urban Demographics, via MR, points to an international survey on car parking rates by Colliers International. The results of monthly parking rates presented in the chart below, shows how cheap parking rates are in Indian cities.



(Please click on the figure to enlarge)

This blog has argued repeatedly about the importance of parking charges in addressing urban traffic challenges. Also see an earlier post on parking charges here.

The counterfactual problem in public policy

Heads I win, tails you lose! This aphorism could well describe the debate on many intractable public policy issues, those where conclusive answers are difficult to come by. Supporters claim that it would have been worse without the intervention. Critics denounce the intervention as a failure since the problem persists. The challenge with all such issues is the difficulty of establishing the counterfactual. Let me illustrate this dilemma with three examples.

The most famous counterfactual problem of our times is the debate on the impact of expansionary policies implemented in the US in the aftermath of the Great Recession. Conservatives point to the persistent high unemployment rates and weak economic conditions, despite the extraordinary fiscal (more than $ 1 trillion) and monetary expansion (zero bound rates and $2.3 trillion QE), as conclusive proof of the failure of expansionary policies.

They reinforce their argument by pointing to the failure of the now infamous recovery projection, estimating future unemployment rates with and without a stimulus plan, made in January 2009 by Christina Romer and Jared Bernstein, then part of President Barack Obama's team. Their way-off-the-mark estimates suggested that unemployment would approach 9% without a stimulus, but would never exceed 8% with the plan.



In May 2011, using the latest figures available from the BLS, the unemployment rate reached 9.1%. In contrast to the Romer and Bernstein projections which estimated that the unemployment rate would be around 8.1% for May without a recovery plan, or 6.8% with a stimulus plan, the actual rate was 9.1%. The actual unemployment rate has been consistently above Romer and Bernstein’s worse case scenario for the economy – and by a considerable margin. Critics of the stimulus invoke this as proof of its complete failure. After all, though a massive and unprecedented monetary and stimulus was enacted, it appears to have had no impact in terms of improving the economic conditions.

Supporters of the stimulus in turn point to other statistics to put forward their claims about how the stimulus created employment, supported the poorest, propped up aggregate demand, and helped local governments. They argue that in the absence of the stimulus measures, the counterfactual, the economy would have plunged into a full-blown depression.

Further, economists like Paul Krugman have consistently held that the actually enacted stimulus policies have been severely deficient and have been advocating much larger doses of expansion to mitigate the high unemployment rate. In the absence of the required magnitude of expansion, they claim, it is unfair and incorrect to blame the expansionary policies for the economy languishing.

Such counterfactual problems are pervasive in economic policy making. This is especially so given the impossibility of localizing and quantifying the impact of specific policy interventions. In the circumstances, if the intervention fails to yield the desired result, critics will denounce it as a failure. Supporters will find that establishing the counterfactual, the scenario in the absence of the stimulus, is fraught with insurmountable difficulties.

Another example of such analysis is the debate about the benefits of metro-rail in New Delhi. Critics argue that despite the massive investments in the Metro, the Delhi traffic remains as bad as ever, even worse. This argument is made on the assumption that the Delhi Metro was set up with the objective of lowering traffic congestion in the city. Now that the final outcome shows no signs of traffic improvement, they argue, the Metro project has failed.

Supporters naturally point that without the Metro Delhi would been uninhabitable. They argue that the Metro has taken 1.7 million people out of the roads, and thereby ensuring that those many people stay out of city roads. They argue that the success of the Metro is a function of how many people it is able to attract and how fast its network expands. The persistent congestion is only a reflection of the fact that the Delhi traffic has been growing at a pace faster than even the growth in the Delhi Metro traffic.

Such criticisms are commonplace with infrastructure investments. They most often fail to produce tangible and immediate impact, and leaves all stakeholders unsatisfied. When the power deficit is a few gigawatts, the commissioning of a few hundred megawatts of power generation capacity has limited impact on the load-shedding situation. Similar situation arises with even major new water and sewerage treatment capacity expansion, since the requirements are massive. The problem is most acute with transportation, since traffic always appears to worsen. In the absence of any salient impact, municipal councils have no incentive to sanction scarce resources in such sectors.

Finally, the left-wing critics of economic liberalization in India point to the persisting high poverty rates and social deprivation and blame it on the neo-liberal policies of the past two decades. They argue that these policies have exacerbated social tensions, widened economic inequality, dismantled social and economic protections and therefore weakened the nation economically.

This too is a classic counterfactual problem. There are two issues here. One, serious commentators question the nature and extent of liberalization undertaken by successive governments, claiming that they have been too little and limited in scope and piecemeal and stop-start. In the absence of, leave alone the full breadth and scope, atleast even some reasonably acceptable level of liberalization, they argue, how can we blame liberalization for the current state of affairs?

Second, they argue that in the absence of this limited economic liberalization, the economy would have been in doldrums. They point to the undoubted macroeconomic gains of recent years as proof of this. How do we know what would have the state of affairs in the absence of the liberalization policies? See Ananth's excellent take on the critics of economic liberalization, including on other dimensions.

In all three cases - stimulus measures in the US, Metro railways in New Delhi, and economic liberalization in India - there is a classic cognitive bias at work, availability bias. People observe salient outcomes - the poor state of the economy, despite the stimulus spending; poor state of Delhi traffic, despite the Metro; and the persistent high poverty levels, despite economic liberalization - and conclude that these interventions failed to achieve the outcome. However, the reality clearly (albeit less so clearly in case of stimulus) points to all having had considerable effect in mitigating the respective problems, though the exact magnitude of their impacts is difficult to quantify.

Then there is another issue here. In all three cases, the opponents frame the debate by equating the particular intervention with the text-book case of the underlying concept. Accordingly, for example, they define the stimulus as was implemented in the US was the classic Keynesian stimulus, and therefore its apparent failure to get the economy out of the recession is conclusive evidence of the failing of the underlying Keynesian concept itself.

Similarly, critics' definition of the success of metro rail as measured by the resultant reduction in congestion rate, means that an actual increase in congestion is taken as proof of its failure. For neo-liberal critics, Manmohanomics is the embodiment of economic liberalization and since it did not "eliminate poverty", as promised, it has failed!

Contrasting tales of traffic management from both sides of the Atlantic

The prevailing traffic management paradigms on both sides of the Atlantic could not have been more contrasting. On the one side American cities are implementing policies that adapt cities to accommodate driving (by intelligent transport systems to improve traffic flow and apps to help drivers find parking spaces), while on the other hand European cities are creating environments that are hostile to cars (congestion pricing, outright car bans from green and pedestrian zones, closely spaced red lights, speed and parking restrictions, pedestrianization etc).

The strategies employed by European cities aims to make car use expensive and difficult and thereby force them into using other modes of transport. As a Times article writes, these policies complement inherent pedestrian friendly conditions,

"Built for the most part before the advent of cars, their narrow roads are poor at handling heavy traffic. Public transportation is generally better in Europe than in the United States, and gas often costs over $8 a gallon, contributing to driving costs that are two to three times greater per mile than in the United States... European Union countries probably cannot meet a commitment under the Kyoto Protocol to reduce their carbon dioxide emissions unless they curb driving. The United States never ratified that pact. "

Over the past two decades, there have been a marked shift towards policies that seek to make cities more inviting, with cleaner air and less traffic. In cities like Zurich, carless households have increased from 40 to 45 percent in the last decade, and car owners use their vehicles less. A stunning 91 percent of the delegates to the Swiss Parliament take the tram to work! Shopping malls and business districts have limited parking lots, thereby incentivizing people to get there on public transport.

Further, even as American cities try to synchronize green lights to expedite traffic flow, European cities have been shortening the green-light periods and lengthening the red light times so as to reduce waiting times for pedestrians. In stark contrast to countries like US and India which stipulate minimum parking space for apartment units and new buildings, building codes in Europe cap the number of parking spaces in new buildings to discourage car ownership. Store owners in Zurich who had worried that road closings and pedestrianization would reduce business have been pleasantly surprised to see 30-40% increase in pedestrian traffic.

Edward Glaeser opposes restrictions that bar drivers for the sake of barring driving (multiple red-lights etc) and favors policies that internalize the social costs (congestion fees, higher parking fees etc). Alex Marshall argues that "a city more oriented around walking, biking and transit is more desirable place to live and work".

Apart from an enabling policy framework, one of the most important but less discussed reasons for Europe's success with policies that restrict car usage is the very high marginal conformity to these restrictions among its citizens. In other words, once regulations are put in place, very few people jump red lights, stray into congestion and pedestrain zones, over-speed or not stop for pedestrians, or park their vehicles illegally.

In contrast, in countries like India, such violations are more common than observance of rules. As I have blogged earlier, the deterrent effect of enforcement acts mainly at the margins, on that minority who are most likely to violate, while it becomes ineffective when the majority are violators. Such violations persist because of their convenience - minimal or no costs, ease, socialization, inaccessibility to alternatives etc.

Having said that, it cannot be an excuse for lax enforcement. Some policies like high parking prices, pedestrianizing certain areas, restricting car usage into city centers at peak times etc, which are relatively less difficult to enforce should immediately form part of any meaningful attempt to reduce traffic congestion.

In any case, in the absence of good, world class, and affordable public transit systems, any set of policies aimed at restricting car use anywhere in the world, while laudable, are certain to fail. Whatever else central, state and local governments in India does to contain traffic congestion, massive investments in world class public transit is a sine-qua-non.

Optimizing transportation networks

I have blogged earlier about this (pdf here) fascinating study of unco-ordinated transportation systems by Hyejin Youn, Michael T. Gastner, Hawoong Jeong. They analyzed the 246 road links and 88 nodes of Boston's transportation network and their conclusion is striking and has significant lessons for urban transport planners,

"Uncoordinated individuals in human society pursuing their personally optimal strategies do not always achieve the social optimum, the most beneficial state to the society as a whole. Instead, strategies form Nash equilibria which are often socially suboptimal. Society, therefore, has to pay a price of anarchy for the lack of coordination among its members. Here we assess this price of anarchy by analyzing the travel times in road networks of several major cities. Our simulation shows that uncoordinated drivers possibly waste a considerable amount of their travel time. Counter intuitively, simply blocking certain streets can partially improve the traffic conditions. We analyze various complex networks and discuss the possibility of similar paradoxes in physics."

They find that contrary to conventional wisdom, the interaction of utility maximizing road users do not result in optimal traffic outcomes. Transportation flows can in reality be far from optimal even if all individuals search for the quickest paths and if complete information about the network and other users’ behaviors is available. In other words, "traffic networks can be inherently inefficient". In a game theoretic framework, they find that the Nash equilibrium (arising from self-interested road use decisions of driver) is different from the social optimum (minimized cost to society per unit transport time).

The study highlights the importance of the Braess Paradox which states that adding capacity to a network in which all the moving entities rationally seek the most efficient route can sometimes reduce the network’s overall efficiency. The graphic below highlights how certain road links add to traffic congestion due to drivers propensity to selfishly optimize on their travel times (which ironically enough, in turn results in higher travel times for the collective).



In many respects, urban transport market is a classic free-market of vehicle and road users - completely unregulated, but rife with information asymmetry (among drivers). Which routes to use and which to not use at any point in time? Which routes are best traversed through public transit as opposed to private vehicles? Which roads can be made one-way? How do we regulate vehicle flows in a road circuit?

The larger lesson it conveys to urban transport planners is about the importance of co-ordination among vehicle-users in reducing traffic congestion. Such co-ordination can be achieved by both bridging the information asymmetry between drivers and through interventions to optimize flows within transport networks.

In the prevailing "build your way out of traffic congestion" paradigm, there is very little attention paid to bridging this information asymmetry and scientifically optimizing the configuration of traffic flow networks. It is therefore not surprising that, like other unregulated free-markets, market failures (manifesting as traffic congestions) abound in this market.

Taming the traffic snarl

Here is my op-ed in Mint today which argues that effective traffic management requires going beyond conventional solutions like road widenings and fly-overs and "requires demand-side measures that encourages public transport usage, discourages private vehicles, and enables human beings to make rational decisions about their travel plans and road usage". The material data used in the article are available here.

The challenge of traffic management

One of the biggest concerns with traffic management in urban centers is the explosive growth in vehicle population, far outpacing the growth in road network expansion.

The standard bureaucratic solution to addressing this challenge is to widen roads and build fly-overs. This is understandable, since it is the easiest solution to implement and generates immediate benefits, atleast for some time. In fact, it is even necessary, since it is important to realize the fullest available carriageway. However, on a longer-term perspective, such measures are only kicking the can down the road.

As has been the experience from across the world and in our own cities, any road expansion triggers off the cliched Parkinson's law. Supply creates its own demand. More carriageway immediately attracts more vehicles.

Any sustainable solution to traffic management requires demand-side measures that encourages public transport usage, discourages private vehicles, and enables human beings to make rational decisions about their travel plans and road usage. An appropriate mixture of these interventions can improve traffic management.

The first requires massive investments in public transit systems and their careful integration with all other modes of transport, public and private. It is as much an exercise in urban planning as transport management. In this context, it is also important to bear in mind that, as experience from across the world shows, such investments have to be heavily subsidized. Most importantly, a good public transit system is a pre-requisite for the success of all other demand side interventions.

Across the world, a large number of countries have experimented with a slew of initiatives to discourage the usage of private vehicles. They have included measures to both make vehicle ownership and usage expensive. For more than two decades, Singapore has a policy that mandates that all vehicle owners have a Certificate of Entitlement (COE). As part of this policy, quotas restrict the number of new cars (to maintain only a certain level of vehicle growth) and vehicle owners have to buy COE permits in auctions. The high COE permit auction rates act as a prohibitive tax on vehicle ownership.

Similarly, in China, faced with exploding vehicle population, Shanghai has for several years now been conducting monthly "license plate auctions". In a reflection of the growing demand for vehicles, bid rates have averaged a record 46,000 yuan ($6,900) in recent times.

Buoyed by Shanghai's success, Beijing recently adopted a lottery system to issue car license plates. It even goes beyond Shanghai and mandates that new registrations are only being given to only those who have paid tax and social insurance in the city for more than five years. Further, cars licensed in other parts of China are now forbidden from driving during peak hours in the capital’s main urban area. All this will restrict registrations to just 240,000 additional vehicles in 2011, a third of the current annual level, and is estimated to take 10 m potential buyers out of the market.

Singapore, London, and a few other European cities have sought to levy congestion charges in certain high traffic density areas to dis-incentivize vehicle usage there at certain times. Many Chinese cities like Guangzhou, Shenzhen and Hangzhou are now toying with congestion charges. Policies that seek to internalize the parking charges are another approach to limit vehicle usage, atleast in certain areas and certain times. Cities like London, Hong Kong, and New York, with their heavy parking fees, impose a huge premium on private vehicle usage. Some Chinese cities like Ningbo are even considering forcing citizens to own a parking space before they can buy a car.

Some of the Latin American cities have experimented with barring odd and even-numbered vehicles on designated week-days. Car-pooling has for long been a favorite in many parts of the US (though it is now going out of favor in many areas).

Finally, it is important to provide people with information about traffic conditions in the most readily usable manner. This will help them make rational decisions on effective road utilization. In many respects, road traffic has striking similarities with a free market. Consumers base their decisions to purchase goods and services based on price, quality, and some other parameters. Similarly, people make their travel plan, route and vehicle usage choices, subject to certain constraints - parking charges, vehicle usage costs, traffic intensity at the time etc.

Like in the free-market, it is possible to generate more efficient traffic outcomes, if people are provided with traffic-related information in the most appropriate manner. This does not mean flooding people with all available information, but channeling it in a cognitively salient and easy-to-use manner. This makes easy for people to make choices that can optimize on their travel times and therefore improve traffic management.

Intelligent traffic management systems, that use technology-intensive devices, which are integrated to each other, can be very effective in effective rendering such information.

More highways and flyovers do not solve traffic problems

The commonest solution to addressing urban transport problems is to expand the road space - either build new roads or widen them or construct fly-overs and elevated express-ways. Planners project it as neat and logical, politicians see it as populist, consultants and contractors view them as cash-cows and people find it sexy. Everyone loves it, atleast in its immediate aftermath.

However, as this post points out, there are serious limitations to this approach. Matthew Philips writes,

"Studies over the last decade (like this one, this one, and this one; plus the book Suburban Nation) have pretty much dismantled the theory that more roads equal less traffic congestion. It turns out that the opposite is often true: building more and wider highways can increase traffic congestion."

Consider the evidence from the US. A 1998 Surface Transportation Policy Project titled "If you Built it, They Will Come: Why We Can’t Build Ourselves Out of Congestion" found that 90 percent of new urban roadways in America are overwhelmed within five years. Another study of 70 urban areas across 15 years concluded,

"Metro areas that invested heavily in road capacity expansion fared no better in easing congestion than metro areas that did not. Trends in congestion show that areas that exhibited greater growth in lane capacity spent roughly $22 billion more on road construction than those that didn’t, yet ended up with slightly higher congestion costs per person, wasted fuel, and travel delay... On average the cost to relieve the congestion reported by TTI [Texas Transportation Institute] just by building roads could be thousands of dollars per family per year."

Another study on the possible impact of the expansion of Washington's highway network finds it unlikely to result in a significant reduction in congestion on the state's roads.

"Academic research and practical experience have demonstrated that increases in highway capacity lead to increases in vehicle travel-reducing, or in some cases negating, the congestion-fighting benefits of the projects."

It suggests increasing investment in transit services and other transportation alternatives, improving the efficiency of existing highways and removing bottlenecks, and ultimately reducing the growth in vehicle-miles traveled (VMT) on the highways. A study by the Texas Transportation Institute finds,

"The effect of lane mile additions on VMT growth is forecast and found to account for about 15% of annual VMT growth with substantial variation between metropolitan areas. This effect appears to be closely correlated with percent growth in lane miles, suggesting that rapidly growing areas can attribute a greater share of their VMT growth to growth in lane miles."

See more evidence from the US on the futility of building (by roads) your way out of congestion in this exhaustive op-ed. This video is an excellent summary of the impact of fly-over demolitions on traffic

Moving Beyond the Automobile: Highway Removal from Streetfilms on Vimeo.

None of this is to argue against road widenings and fly-overs. Given the population sizes involved, municipal governments will be forced to maximize on road carriage-way through widenings and fly-overs. However, as these examples show, we have to be wary of seeing them as part of long-term urban transport problems. A fresh supply of road carriage-way, it appears, creates its own demand!

The BRTS capital of the world faces a reality check?

Last decade, many Latin American cities, led by Bogota in Colombia, had successfully pioneered the use of innovative bus transit systems that have been catalysts for the economic transformation of these cities. The Bus Rapid Transit System or BRTS, with dedicated bus lanes, became the rage of urban planners across developing countries. It was held up as an environment friendly model to address the chronic urban traffic problems of the exploding cities in developing countries. And it was far cheaper than the fancy subway systems. The Times describes the BRTS,

It is more like an above-ground subway than a collection of bus routes, with seven intersecting lines, enclosed stations that are entered through turnstiles with the swipe of a fare card and coaches that feel like trams inside... To create TransMilenio, the city commandeered two to four traffic lanes in the middle of major boulevards, isolating them with low walls to create the system’s so-called tracks. On the center islands that divide many of Bogotá’s two-way streets, the city built dozens of distinctive metal-and-glass stations. Just as in a subway, the multiple doors on the buses slide open level with the platform, providing easy access for strollers and older riders. Hundreds of passengers can wait on the platforms, avoiding the delays that occur when passengers each pay as they board.

Bogotá’s TransMilenio BTRS has been central to a dramatic transformation of Colombia's once drug-war torn capital city. In 2009, the TransMilenio was used for an average of 1.6 million trips each day, and has allowed the city to remove 7,000 small private buses from its roads, reducing the use of bus fuel — and associated emissions — by more than 59% since it opened its first line in 2001. In fact, thanks to its extensive route system, TransMilenio moves more passengers per mile every hour than almost any of the world’s subways.

Apart from its affordable and easy to implement nature (Subways cost more than 30 times as much per mile to build than BRTS, are three times as much to maintain, and can be built more quickly), the BRTS is the most environment friendly of transport interventions. As the graphic below shows, it has the lowest per capita emission rate, and can make a serious dent on the smog that envelopes most major cities across the developing world.



As the Times pointed out, TransMilenio success came with several important complementary policies,

"The negative stereotypes about bus travel required some clever rebranding. Now upscale condominiums advertise that they are near TransMilenio lines. People don’t say, ‘I’m taking the bus,’ they say, ‘I’m taking TransMilenio'... Free shuttle buses carry residents from outlying districts to TransMilenio terminals... Bogotá removed one-third of its street parking to make room for TransMilenio and imposed alternate-day driving restrictions determined by license plate numbers, forcing car owners onto the system."

However, underlining the complexity of the challenge facing urban transport planners, a recent Times article points out that TransMilenio may have become a victim of its own popularity. It is now hobbled by long waiting lines, overcrowded buses and delays and corruption in building new routes, and has also become a setting for armed robberies and violent protests. Most critically, it faces the challenge posed by the exploding private vehicle population of the city. Vehicle sales in Bogota surged to 25,527 in February, a 51% jump from the same month a year earlier, worsening its traffic jams.

Bogota is only the latest example of cities which have struggled with the complex challenge of urban transport despite apparently successful transport policy interventions. Many emerging economy cities build fly-overs, widen roads, by-passes, establish meto-rail lines, or improve traffic signalling integration that provide immediate relief. However, it is rarely long before the same problems re-surface. It is therefore worth reiterating for the upteemth time that any sustainable solutions to urban transport has to involve a comprehensive package of interventions as highlighted above.