Urban public transport modes include buses, trolleybuses, trams and trains, rapid transit (metro/subways/undergrounds etc) and ferries. Public transport between cities is dominated by airlines, coaches, and intercity rail. High-speed rail networks are being developed in many parts of the world.
While in theory public investments into urban mass transit could reduce the cash and time cost of transit for low-income users, as with road investments, the conditions whereby these benefits can be captured by the poor are highly specific. In practice, stimulating sustained investment into mass transit in a developing country context is even more complex for the urban transit sector than for the road sector.
The United States lags behind other developing countries in its funding for urban transportation and infrastructure upgrades. Equally important, with the focus on improving the economy and stimulating job creation, there is economic gold in the roads and bridges that we travel on daily. Reviving the urban transportation system in this country not only reinforces the aged and dangerous infrastructure, but also creates a nationwide framework of jobs.
[Bradford] Snell charged that General Motors had destroyed mass transit in the United States by purchasing controlling shares of electric rail- ways and converting them to diesel bus operation, not only to sell more GM buses but to weaken mass transit, forcing Americans into GM cars.
Metro’s scale has helped create the kind of transit-oriented development that many cities only dream about. A developer who builds an office build- ing or condominium close to a Metro station gains access not to a single corridor but to an entire region, benefiting from what economists call “network effects.”
In the 1960s, Warren Quenstedt, a major player in planning rail for Washington, was asked how the process worked. He replied, "You start by asking: What kind of city do you want?" Only once that question is answered can planners determine the proper roles for rails, roads, buses and other modes of transportation -- including cars -- in a city's design.
The economist Joe Cortright showed in a study for CEOs for Cities that the UMR obscures the fact that people who live in cities with transportation options and less urban sprawl generally have shorter commutes. That means a lower proportion of the population is subjected to highway congestion than is true in places where long automobile commutes are the predominant option.
A city needs a variety of transportation and land use options, not just one . Providing a wide range of options can build resilience into an urban area, especially when it faces crises like climate change and the peaking of world oil production, as well as the need to address a wide range of economic and social functions through transportation . On average, urban car travel uses nearly twice as much energy as urban bus travel, 3.7 times more than light rail or tram travel, and 6.6 times more than electric train travel.
Large increases in urban population and pollution have seriously compromised existing transportation systems and significantly increased the challenge of creating future transportation systems. And "despite extensive spending on urban transportation systems," the problems "seem to only get worse."
Some of the most innovative public transportation systems, those that shift huge numbers of people from cars into buses, have been developed in Curitiba, Brazil, and Bogotá, Colombia.
Urban transportation is a complex phenomenon. Since many agents are constantly interacting in parallel, it is difficult to predict the future state of a transportation system. Because of this, optimization techniques tend to give obsolete solutions, as the problem changes before it can be optimized. An alternative lies in seeking adaptive solutions.
Transportation is vital to U.S. urban life and to life on other places as well because it is an absolutely necessary means to an end: It allows people to carry out the diverse range of activities that make up daily life. Because cities consist of spatially separated highly specialized land uses - […] - people must travel if they want to obtain necessary goods and services.
Cities exist when there are special advantages to carrying out economic activities in proximity, advantages often called "economies of agglomeration" because costs are lower when certain groups of activities locate close to each other. The primary reason for agglomeration economies, especially in a world with low communication costs, is that transportation costs are still significant and proximity reduces them. A corollary is that anything that reduces transportation costs within an urban area increases the extent to which its activities are easily linked to each other, and thus takes further advantage of agglomeration economies. In a world of many competing urban centers, those with more efficient transportation systems have an advantage.
Whether shortages of transportation infrastructure investments are limiting productivity growth thus remains a question that is difficult to answer. But the challenge of transportation infrastructure investment goes much further than simply increasing spending through existing institutions and programs. For that will not improve productivity of it generates projects that are economically sound but impossible to build for political reasons, or are politically attractive but economically unsound.