AP® Human Geography review sheet from Aim for Five (aimforfive.com/geo/units/6/6-8)
Unit 6 · Topic 6.8
6.8 Urban Sustainability
Planners try to make cities more sustainable and livable with mixed-use development, walkability, transit-oriented development, smart growth, New Urbanism, greenbelts and slow-growth policies. These ideas can cut sprawl and car use, but critics argue they can also raise housing costs and push lower-income residents out.
Key terms
- mixed-use development
- walkability
- transit-oriented development
- smart growth
- New Urbanism
- greenbelt
Key design ideas
- Mixed-use development: combining homes, shops, offices and services in the same building or neighborhood, like apartments above stores, so daily needs are close by.
- Walkability: how easy and safe it is to walk to places, with sidewalks, short blocks, crosswalks and nearby destinations.
- Transit-oriented development (TOD): dense, mixed-use building clustered around transit stations. Copenhagen's Finger Plan (1947) directed growth along rail lines extending from the city like fingers, with green space between them.
- Smart growth: policies that steer growth into existing areas and away from open land, with compact building, a range of housing types and transportation choices.
- New Urbanism: a design movement that builds neighborhoods like traditional towns, with front porches, sidewalks, narrow streets, a town center and homes close together. Seaside, Florida (begun in 1981) is the famous early example.
- Greenbelts: rings of protected open land around a city where development is restricted. London's Metropolitan Green Belt dates from the mid-1900s.
- Slow-growth cities: places that limit how fast they grow, for example by capping building permits each year. Petaluma, California, set such a cap in the early 1970s.
Why supporters favor these ideas
- Less sprawl, so more farmland and natural land are protected.
- Fewer and shorter car trips, which means less traffic, air pollution and greenhouse gas emissions.
- More housing choices, from apartments to townhouses, in a single neighborhood.
- More livable places, where people can walk to shops, parks and transit and meet neighbors.
- Lower public costs, since compact areas need fewer miles of roads and pipes per household.
Criticisms
- Higher housing costs: limiting where building can happen, through greenbelts, growth caps or strict design rules, can restrict supply and raise prices.
- De facto segregation: if new walkable neighborhoods are expensive, they can end up mostly wealthy, separating people by income and often by race without any law requiring it.
- Loss of character: redevelopment can replace older buildings and the businesses and communities that gave a place its identity.
- Limited reach: a single New Urbanist development can still sit in a car-dependent region, so residents keep driving for work and shopping.
Balancing the trade-offs
Most planners see these tools as trade-offs rather than simple wins. A greenbelt protects open space but may push development to towns beyond it, where people then commute long distances. Transit-oriented development cuts car use but can raise rents near new stations. Planners often pair sustainability policies with affordable-housing rules like inclusionary zoning (6.10) to share the benefits more widely.
Worked examples
Try each one yourself first, then open the solution.
- Example 1
Benefit and drawback of one policy
Describe one benefit and one drawback of a greenbelt around a city.
Show the solutionHide the solution
- Step 1: Define it: protected open land around a city where building is restricted.
- Step 2: Give a benefit with a mechanism: it stops sprawl and protects farmland and nature.
- Step 3: Give a drawback with a mechanism: it limits land for new housing, so prices rise, or development leaps beyond the belt.
Answer: Model answer: A greenbelt, like London's, protects farmland and green space by stopping the city from spreading outward. However, by limiting the land available for new homes, it can push up housing prices inside the city and push development to towns beyond the belt, which lengthens commutes.
Common mistakes
- Giving only benefits. The CED expects you to know both the praise and the criticisms of these policies.
- Confusing smart growth with New Urbanism. Smart growth is a set of regional policies; New Urbanism is a style of neighborhood design.
- Defining mixed-use as mixing housing types. It means mixing different land uses, like homes with shops and offices.
On the exam
- Expect a stimulus showing a neighborhood design or plan. Identify the strategy and explain one benefit and one drawback.
- Use specific terms in your answer: transit-oriented development, walkability, greenbelt, New Urbanism.
Connected topics
Videos
Check yourself
4 questions on 6.8 Urban Sustainability. Pick an answer to see if you got it, and why.
A planned community has narrow streets, front porches, homes above shops, and a town square within a five-minute walk of most houses. These features reflect
A city rezones the land around a new commuter rail station for apartments, offices and stores, with wide sidewalks and limited parking. This is an example of
London's Metropolitan Green Belt is a ring of protected open land around the city where most new building is restricted. Which is a common criticism of this kind of policy?
Planners in a city adopt smart growth policies, including more mixed-use development and walkable streets. Which outcome would critics most likely point to as a concern?
0 of 4 answered