The Importance of Integration in Scalable Mass Transit Systems

By Ted Oberwager

The logic behind developing the world’s mass transit systems is obvious: a smaller carbon footprint, reduced dependence on gasoline, decreased congestion, job creation, and ultimately dollar savings for governments and consumers alike. The ramifications are huge both for the ~9,400 new cities that are expected support global population growth, but also for the many existing metropolises that will need to absorb additional headcount. With the United Nations predicting that cities will absorb the vast majority of the nearly 2.5 billion increase in the global population through 2050[1], I believe that scalability is the #1 issue facing mass transit today.

The question then becomes – how do we best scale mass transit systems in the cities of the future? Given the magnitude of our transportation needs, the answer cannot be found in any one solution. While many promote the virtues of one form of transit over another, there will not be a ‘silver bullet’ approach. Even the best constructed subway cannot solve a bustling city’s transportation needs in isolation. And creating a scalable system can be an issue of life or death proportions – just consider the news from India today where overcrowding in an Allahabad train station caused panic and stampede leading to the death of at least 37 people.[2]

Thus, I believe the answer must lie in a fully integrated approach across transportation modes. The public sector has many options to address its transportation needs – buses, trains, subways, aerial solutions, and even car sharing – and governments will need to use all of them going forward. The ability to connect and coordinate these alternatives will be the differentiating skill that makes a mass transit system truly scalable. It is not difficult to imagine a world where our smartphones tell us to ride the subway over the bus for our morning commute, or a software program with connection to all modes of mass transit helps city managers dynamically alter transportation prices to help balance loads and improve capacity utilization. We often think of the “smart grid” as an interconnected electrical grid, but that “grid” may soon be expanded beyond the electrical to include an integrated system of roads and rails and tubes.

How and when we realize this vision is unclear. As we saw in our Living PlanIT case, we are very much in the first inning of integrating our cities and making them truly “smart,” but the necessity of these innovations seems clear. And with companies like Cisco and Oracle attacking these issues head on[3][4], it can’t be too long before we rethink what it means to have a “smart grid” in the context of our public transportation systems, thereby making our cities truly scalable and efficient.


Success of Tollway Projects vs. Mass transit Systems

By Anonymous

Is it accurate to state that it’s easier to capture the value of saved time in a toll highway situation than in a mass transit MRT/BRT situation? If this is so, why is it so? How would this situation be mitigated?

The success of tollway projects throughout the world and the continual struggle of mass transit systems, particularly metros/subways, to operate profitably despite very high ridership suggests that it is significantly easier for the state to capture the value of saved time from drivers than riders. But why is this?

One potential explanation is that users of mass transit have lower ability to pay, and/or a lower valued of time, than drivers. Both of these are likely true, particularly in developing countries. However, although riders of public transportation have a lower value of time, they also likely have fewer alternatives. This is not to say that those with fewer alternatives should be overly burdened, but to suggest that perhaps there may be greater ability to recoup costs and thus offer a high level of service.

Another explanation is socio-political: it is not just that it is more difficult to capture value, but it is less socially and politically acceptable to do so from those who, as mentioned, have fewer alternatives. This explanation seems the most probable – just as societies today tend to have progressive tax codes and various degrees of social welfare programs, our transportation systems also reflect our collective belief on how the burden of public goods should be allocated.

Is this a situation which must be rectified? That depends. Well-funded cities have mitigated the situation by continually subsidizing the operations of transit systems, and this has worked most of the time. Yes, there is a fair bit of complaining and angst every time the subsidy hits a ceiling and fares must be raised, bringing up the question (again) about why the system must subsidized at all, but isn’t an on-going subsidy just another way of capturing value? The subsidy is funded, of course, by taxpayers – including the vast majority of riders.

For less well-funded cities, however, the answer is more complicated. If lack of stable funding is precluding a transit system from being built, and the transit system has real valuable benefits, an alternative method of funding is needed. One idea is a clearly defined municipal transit tax. This would introduce a more predictable revenue stream and thus lend support to development of a system, and if the benefits of a system are real, presumably the public will be willing to fund it.

Adding a Subway to San Francisco

By Tina Adams

For one of the wealthiest cities in the world, San Francisco has surprisingly inadequate public transportation. Mayor Ed Lee noted that improving the city’s “notoriously late and overcrowded public transit system” is his top priority.[1] Although the SF Muni does millions of rides per year, it is the slowest transit system in America, averaging about 8 mph.[2] The system is above ground and must deal with traffic and many traffic lights.

I was pleasantly surprised to find out that there is a plan to create the Muni Central Subway (CS), which runs 1.7 miles from the Caltrain station to Chinatown. The CS corridor has some of the highest commuter traffic in the city. I was shocked, however, at the projected cost of $1.6 billion for the line.[3] Per mile this is 1.7 times higher than the highest metro cost we saw in the Bogota case (for the London extension). This perhaps showcases why it is better for a city to build subways while it is transitioning from a developing to developed economy, since costs appear to grow astronomically with development due to high property values and contractor costs. The new Muni Chinatown station alone will likely cost over $300M.[4]

Before this class I would have said unequivocally that the CS is a godsend. Now I wonder both whether the project is in fact worth it and whether it was funded in the appropriate manner. The CS reduces rider time in the corridor from 20min to 8min for the expected 65,000 customers per day.[5] While it will provide a quicker connection between Caltrain and BART, the CS’s short length leaves commuters with the same problem as before: they have to transfer between 3 different transit systems to get to work! In the Bogota case we discussed the problems associated with implementing multiple types of transit in one city. No exception here. CS comes with large and complex transfer stations, meaning that the 12 minutes saved in high-speed rail may easily be lost in transfers. In my mind a better solution would have been a longer line to lesson the need for transfers. A longer line may also have gotten better economies of scale, thereby reducing the cost per mile.

Of course the question remains, could a longer line have been funded? I believe so. The CS is currently funded by about $1 Billion in federal funds, which took over 4 years to procure.[6] Additional funding is coming from state and city coiffeurs. I believe a more substantial project could have been undertaken through a public private partnership. CS is widely touted as an “economic engine” for the city, connecting major job and retail centers and bringing SF closer to businesses in the Peninsula.  Given this, many corporations are set to benefit from a more substantial subway system. A longer line could be funded by bringing corporations into the fold through a consortium similar to what we saw in the Poland case.

Making Sustainable Decisions

By Yiran

There are thousands of “sustainable” ideas in the world, BRT, metro, GPS, etc.; but not every city is adopting every single one of them. Why not?

Despite the financial and technological constraints, the major question we should ask at the beginning is, “Is this idea really suitable for our city?” Only when the answer is “Yes” can the quote mask could be removed from the defining word “sustainable.” However, in rapidly urbanizing cities, this question has been long forgotten and the supposedly “sustainable” ideas that are not suitable for the cities are now creating an unsustainable future for them. Therefore, how public sector and private sector can work together to make real sustainable – sustainable and suitable (S2) – decision for cities remains a critical problem.

Public Sector: Decision Maker

Focusing on the public sector’s needs is very important because they are the final decision maker. What do those politicians want? Political benefit, economic growth, and, if it is a moral politician, public good. It’s not uncommon that first two needs could outweigh the third pursuit, and this situation produces unsustainable decisions that are not in the long term public interest. For example, following the first subway project started in 1965, China now has 25 cities constructing subways[1], and 18 cities constructing BRT[2]. Are metros and BRTs really necessary and feasible for so many cities? Unfortunately the answer might be “No”. My investigation with World Bank Transportation unit of one of the cities, Nanchang, China, indicates that the massive 5-line subway construction plan will add a heavy financial burden to the small second-tier city. However, subway and BRT projects are attractive to politicians because they meet their needs as follows:  First, the “large” and/or “advanced” projects could bring to the city huge funds from various sources as well as achieve apparently high GDP in short time [from short term construction projects], from which the leaders could obtain economic interests. Secondly, these projects are “advanced”, “sustainable” and very visible, so that they could easily draw attention from the central government, and thus the politicians could build up their political profiles.

Private Sector: Game Player and Change Maker

Despite the perception that some leaders tend to make decisions for their own interests, there are entities who are trying very hard to make the decision making process more scientific. The auxiliary forces include experts from planning and design department and institutes, and from non-government sectors such as the World Bank, etc. To some degree they could influence a mayor’s thoughts, but more often they have to give up their insistence and choose the second best alternative in order to meet the leaders’ requirements. Without guaranteed authority, the experts’ power is limited.

A smart move for private sector firms to increase their influence is to tailor their sustainable ideas to meet the politician’s needs. One example is to visualize the proposal of a transportation mode using a simulation modeling to help the politician see the possibilities to could really understand what result their decision would lead to[3].

Institutional & Legislation (I&L) System: Regulator and Interest Balancer

Not only could politicians make unsustainable decisions solely for their own political and economic interest, but the private sector could also make unsustainable proposals that could maximize their financial benefits, and cater to politician’s interests, but not be beneficial for the people. Thus, an I&L system that guarantees public good is indispensable. The I&L system should have an institutionalized project prioritization process that could make the selection of competing projects to be invested more scientific. The I&L system should have a regulatory and punishment mechanism that could prevent the sole realization of city leaders’ political and economic interests by ensuring experts’ power. The I&L system should include a viable public participatory institution that is special-designed for each municipality’s condition, so that the peoples’ voice could be heard and the I&L system and democracy could be mutually-promoting and mutually-supplemental.  Therefore, in the long run, a scientific I&L system could lead to a more collective and rational selection among competing goals and interests.

In sum, by focusing on the needs of decision-makers first, then making private sector and public sector work collaboratively with each other, the best decisions can be identified and then adapted through an institutionalized project prioritization process that leads to sustainable decisions.

Sustainable Southern Systems: Developing Mass-Transit Solutions for the American Southeast

By John Clayton

The Southeastern US continues to see significant population growth, clustered not just in large cities such as Dallas, Atlanta, or Houston, but increasingly in mid-scale cities such as Charlotte, Austin, and the Research Triangle region. Migrants to the region are pulled by a relatively high quality of life at a low price tag, fueled by large inventories of cheap housing. When coupled with a lack of natural land barriers, denser development is inherently discouraged in favor of massive urban sprawl. As the attached graphic shows, Atlanta is home to a population roughly equivalent to Barcelona’s, yet has a 20x larger geographical footprint. Raleigh has an average density of 4 people per square hectare compared to Barcelona’s 176 people. Given such sprawl, what type of transit solution could possibly work?

As we discussed in the Bogota TransMilenio case, large metros work well and can be sustainably financed in a handful of mega-cities (Seoul, Shanghai, Singapore), particularly when strong government can derive additional funding sources from rising land values around metro stations. BRT systems offer less capital-intensive solutions, but may be less palatable to a population with high car ownership rates. Light rail is a lower-cost alternative to heavy-rail systems in major urban areas, both less expensive than traditional metro systems yet differentiated enough from existing transit options to convert drivers.

Applying light rail transit systems to less dense cities, however, is tricky: it requires connecting existing higher-density nodes (universities, shopping complexes, downtowns) with green- or brownfield spaces that can channel future high-density development. Charlotte’s new Lynx light rail system offers an excellent example of the ideal mix of transit stations: it connects highly-trafficked areas such as Uptown, the convention center, and Southpark Mall, with previously undeveloped tracts of land; it then worked with developers to incentivize the construction of residential, commercial, and retail units around each station.

Assuming a city finds a suitable transit system, the most significant obstacle still remains: the financing hurdle. Faced with a populace generally skeptical of increased taxes and local government largesse, cities should turn to innovative financing schemes to help offset the infrastructure and operating costs. As our discussion of Hong Kong’s system highlighted, planned urban infill offers three key benefits: 1) it builds city density, thereby reducing sprawl; 2) it clusters residents around the transit stations, diverting more traffic and increasing ridership rates; and 3) it causes land values in surrounding areas to appreciate.

To harness this financing opportunity, cities should design transit systems that both connect high-traffic areas and traverse undeveloped land tracts, then enter into public-private partnerships with developers to build high-density mixed-use neighborhoods. Such collaboration would not only allow governments to capture a slice of increased land values, but also directly influence features such as below-market housing units and city infrastructure such as schools.

Of course, such a partnership would have its share of skeptics. Many Southerners are skeptical in general of government involvement in projects and unfamiliar with PPP schemes, and could perceive a government conflict of interest in development promotion. These concerns could be assuaged by a public relations campaign and consultations with PPP experts. Coupled with long-term development plans that continue to prioritize smarter, higher-density development, Southern cities from low-density sprawling giants to sustainable transit meccas.

Clayton Atlanta Barcelona


Comparison of the geographic footprint of Atlanta and Barcelona (source: Alain Bertaud,

Congestion Pricing – An asset-light BRT?

By Anonymous

The two transportation schemes we discussed in class, BRT and MRT, both have very similar goals in mind: reduce congestion and pollution and increase safety while getting more people to their destination faster. The major constraints for both systems are the huge up-front capital costs and the lack of flexibility once the system’s major lines are in place. One interesting aspect, however, is that neither system deals with the other major source of congestion, pollution and accidents: cars. On the contrary, during our discussion the need to eliminate car lanes on behalf of BRT as the system expands to new areas was a major drawback.

If we take a step away from this car-centric perspective and examine ways to manage all transit options on existing roads, there is a transportation scheme that accomplishes the stated goals in a much more flexible and dynamic way with lower capital requirements upfront: congestion pricing.

In the case of Bogota, the system would charge cars and buses for accessing certain avenues and major traffic arteries according to the time of day and the level of congestion. The fees would keep cars off the road during rush-hour and encourage the use of buses, assuming the system establishes appropriate pricing tiers across time and between cars, buses and taxis. The increased fixed cost would discourage empty buses from running and encourage industry consolidation. In order to encourage the use of newer and greener busses, the pricing could be structured to give low-emission vehicles an edge. A less congested system with fewer competing bus lines would also make transit safer and decrease travel times for commuters.

Initial capital cost to establish the system would also be much lower because traffic control systems could be installed above the street at lower costs than digging tunnels or adding separate bus lanes and platforms. From an infrastructure standpoint the congestion pricing system is much more flexible to expansion as new routes can be added or eliminated in a matter of days not years. On the revenue side, this system starts collecting revenue very soon after installation and provides a safer return on investment to the city.

Of course, this system also has trade-offs. For example, the enforcement of violations is crucial to as successful launch. If the political system is unlikely to punish those who drive without paying, congestion pricing will not improve the current situation. In addition, the implementation of this system hurts a much bigger political constituency (not just bus drivers, but all drivers) which makes this implementation much harder from a political standpoint. Furthermore, it is uncertain whether such a system can support the anticipated growth in travelers and residents over time.

Compared to BRT and MRT, the congestion pricing system would be a much less capital intensive and dynamic solution to the traffic congestion problem. However, this alternative likely has a much higher political price.


BRT vs Metro

By Neil Padukone

When Bogota, the cradle of the world’s Bus-Rapid Transit (BRT) thinking, explored a metro system, debates over preferability raged.

Transit demand depends not only on population and demography, but also on spatial distribution. If people live far away from a metro station, that “last mile” might make traveling so difficult and time-costly that taking the metro is not worth it at all.

Of course, an argument for a metro is that, over the long-term, big infrastructure like metros would induce demand for high-density (potentially mixed-use) living and business investment. In the 1920s, New York’s subway system extended to a barren and unsettled Queens, NY (see Figure 1). That changed tremendously when Manhattan boomed and its residents needed new housing; the area has become one of the highest density areas in the country (see Figure 2).

Fig 1. Queens in 1920s

Fig 1. Queens in 1920s

But the potential for induced demand depends on migration & growth patterns: it won’t happen if there isn’t enough growth to underwrite it. The “People Mover” in Detroit was supposed to induce demand in a contracting Detroit economy. But that wasn’t sufficient; it wound up being a glossy project that wasted money — designed for 15m people, it only served about 2m, and the cost per passenger mile was $4, compared with the New York subway’s $0.30 per passenger-mile.

Fig 2 Queens Today

Fig 2 Queens Today

The thinking in Detroit — and elsewhere — evokes another perennial consideration for the development of metro systems: aesthetics. Metros give off an appearance of legitimacy, sexiness, investment, and stability that buses may not. This sexy infrastructure may well attract other investment, but it often comes at the huge expense of massive state subsidies and deficits: Metros are almost never financially solvent. The only two subway systems in the world whose operating costs are covered by the system are in Hong Kong, which covers operating costs through real estate, and Singapore, which has long had an aggressive car-restriction policy that drove the metro’s farebox ratio up to 126% of operating costs. (Capital costs everywhere require subsidies).

For a long time, metro systems were the only technologies capable of providing the sort of scale for longer-distance urban mobility. But with the improvement of bus technology — segregated lanes, GPS-based sensoring, and tinier capital costs — BRT generates comparable (though admittedly unequal) scale with the long-term ancillary benefit of lowering traffic congestion by taking up space and dis-incentivizing car usage.

The respective capital (costs) of metros and BRTs are another consideration. During its construction and development, the problems that afflict any burgeoning BRT would also afflict the Metro: the time for implementation would bring little short-term respite, and in fact cause greater delays in the interim. And in the long-term, BRT corridors are far more flexible and mutable: If demand for a corridor increases or diminishes, it can simply be deconstructed and redirected for an extremely low cost — relative to subway systems, which are fixed and can’t be redirected quite as easily.