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Cities of Today, Cities of Tomorrow

Unit 3: What is a City Made Of?
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How a city works... and how it doesn't

With their crowded streets and air pollution, cities are better known for their chaos and grime than for their efficiency and organization. Those who have access to such things as water and electricity often take them for granted. Those who do not will obviously not consider the urban system an efficient one. Yet, it is. By and large, people in cities are better off than those who live in rural areas. They have greater access to safe water and sanitation as well as to schools and hospitals. Unfortunately, this is a generalization and not every citizen benefits from a city's offerings. Close to 600 million urban dwellers worldwide live in conditions that put their health and their lives at risk.

Population density and efficiency
One potential advantage of urbanization is the concentration of many people in a smaller space. The concentration of people in a specific area is called "population density" and is usually calculated in population per square kilometer. So, if 1,000 people live in an area of 1 square kilometer, the population density of that area is 1,000.

While a "high population density" can create overcrowded and unhealthy neighborhoods in some cases, it also offers the possibility of delivering the necessities of life with greater "efficiency". If 100 people are spread out over an area of 100 square kilometers, getting electricity or piped water to each of them requires a lot of wiring and plumbing, which means a lot of work and high costs. On the other hand, if the same hundred people live in a few buildings on one block, it would require much less work and resources to provide them with the necessary goods and services.

Infrastructure and services
To take advantage of this idea of "efficiency", to get water, electricity or gas to people, to provide them with educational opportunities, to make sure that garbage and sewage is safely disposed of, to do all of this requires a complex process of planning and building an "infrastructure" and delivering "services".

Education, electricity, health care, markets and public transport are examples of services. But such services require an "infrastructure" to help their delivery. Plumbing, electricity lines, road systems, drainage and sewers are examples of infrastructure. These are the things that keep a city running, the city's support system. How would we get water without plumbing? Electricity without lines? How would buses get around without roads?

Services are the great advantages of a city, one of the reasons why people move to cities. In an ideal world, everyone would benefit from them. In reality, a great number of people don't have proper access to many services, including water and even housing.

Here are some examples of the problems in providing citizens with their needs:


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