- Housing density
- Living space is smaller, which results in a lower need for heating, cooling, lighting, and stuff to fill the space. (See note 1 below to explore this in Footprint USA)
- Use of land is much more efficient, because living spaces are stacked up in tall buildings
- By sharing walls, floors and/or ceilings, living spaces are connected to more spaces at the same temperature, making for further increases in heating and cooling efficiency
- Without back yards and their attendant grass and pools, there is much less water use per household.
- Many people do not have cars, which means they don't need garages. Or parking spaces. And they don't need to buy, ensure, maintain or fuel cars.
- Traveling less
- When cities integrate living, working and retail spaces, people can walk more often to their destination.
- When trips are too far for walking, the density of travelers and destinations makes public transportation practical.
- Public transport, when fully utilized, is much more resource efficient than personal vehicles
- Even when not more efficient that personal vehicles, the shorter trips made by public transport within cities still save resources over personal vehicles traveling longer distances fro suburbs to commercial areas
- Provide access to high quality health care, education, and entertainment
- Housing mobility: More people rent than own, which makes it much easier for someone to choose to move to take advantage of new opportunities
- Job mobility: With a higher density of companies in a small area, there is more interaction between people in different companies and industries.
ChallengesAt the same time, cities provide some challenges that need to be addressed to draw more people to them:
- Expensive housing: This is a big challenge that can only be met with increases in the supply of housing. One way to achieve this is to convert primarily business zones into more mixed use. Mixed use areas, where people have a reason to stay in the area other than for work, provide many other advantages cogently described in Jane Jacobs' classic work Death and Life of American Cities, published more than 50 years ago.
- Lack of green space: Urban areas like San Francisco, Manhattan, and Chicago have large green spaces and waterfronts that give people a place to play and enjoy nature. It is also possible to build more green spaces into our structures, as in the re-imagination of Chicago's Marina City Towers, below (source):
- Potential for higher crime: Many cities have high crime areas. Jacobs makes a case for mixed use urban areas, where people are on the street, or looking down at it, at all times of day, rather than just 9 to 5. Also, when people live in an area, they are more likely to get to know each other, making it harder for anonymous transient criminals to prey on the public.
- Manufacturing and agriculture not nearby:
- Manufacturing is a relatively small employment sector, as most manufacturing is done overseas, and the production in the US tends to be geographically isolated. Thus manufactured items need to be transported long distances no matter where people live. If people live more densely, then there are fewer destination points for manufactured items, which makes their transport more efficient.
- With regards to agriculture, vertical farms, described in The Vertical Farm: Feeding the World in the 21st Century by Dickson Despommier, are a compelling way to bring food production near to population centers, provided that plentiful renewable energy is available.
The Bottom Line
Note 1: Exploring housing density in Footprint USA
- In the Visualization menu, select Selection Summary
- In the Data menu, select Population -> Number of Rooms -> All
- Select County in the Visualization menu
- Zoom in on the New York City area (by Long Island)Tap on the tall skinny county, New York County.
- Scroll down in the Selection Summary view to the Homes section, Number of Rooms subsection. You should see view similar to that shown below:
- Copy the selected data. If you have Numbers installed, paste it into a spreadsheet.
- Go back to footprint and select another county - I choose Putnam, the light colored roughly rectangular county above New York County.
- Copy the same data, paste it into the spreadsheet next to the first set, label the columns and generate a bar chart. Here's what I got: