On a global scale, more people are moving to cities than ever before. We are now building cities for 3 billion people, a doubling of the urban environment. Sustainable cities are critical for creating a livable future for humanity. For Peter Calthorpe, founder of Calthorpe Associates, the largest problem with existing cities is the issue of sprawl.
When people in America think of sprawl, we think of cities like Houston that have high-density centers, low-density housing and commercial districts on the periphery. As the Economist stated in an article on the city, “For a view of Houston’s economy, get in a car.”
But, according to Calthorpe, sprawl can be more broadly described as city design that “isolates people” into separate land use enclaves and hampers the cross-fertilization of commerce and ideas. He points to China’s superblocks as an example of how sprawl can manifest itself in very high-density areas.
China is an example of another type of sprawl: high-density sprawl, with everything isolated in superblocks. Chinese superblocks are often gated blocks with upwards of 5,000 units in them. No one knows their neighbors. There are no sidewalks or ground floor shops. It’s completely sterile.
“Each superblock has repetitious, high-rise apartment towers with a total of around 5,000 units. My design is made up of small urban blocks with green courtyards, each having only 500 units, where you can walk or bike to eat and shop -- where neighbors can actually recognize one another. The buildings will vary from four stories to 30 stories. And this design will house the same number of people per acre while leaving enough open space for parks and greenways.
One of the things we're finding is that the city government can make more money selling land this way, because they now have more customers. When you build in this pattern, smaller developers can participate -- not just the big guys who put up the superblocks.”
China has a huge incentive to rethink cities quickly. About 300 million Chinese are expected to move into urban environments in the coming years. And the government has hired Calthorpe Associates to come up with a master plans for six cities in China to make this a smooth transition.
The firm created a master plan for Yuelai Eco-City in Chongqing, a city of 30 million. The site aims to be a leader in low carbon development “with a special emphasis “on sustainable transportation, infrastructure, and energy-efficient uses.” Calthorpe tested his alternative to sprawl in part of the city and used some principles that leaders of the Chinese government subsequently adopted.
The urban design principles of Yuelai Eco-City include:
Preserving natural environment and agriculture. To facilitate pedestrian mobility along steep slopes, hillside elevators have been proposed on special pedestrian streets that will be lined with retail uses, mirroring Chongqing’s traditional shopping streets. Traditional hillside architecture of the region has been studied and adapted to create a diverse range of building typologies for Yuelai.
Creating mixed use and mixed income areas. Mixed-use development has become a standard in urban planning because of its many benefits, including greater housing variety, strong neighborhood character, shorter distances between work and housing, and pedestrian-friendly environments.
Walkability. To reduce dependence on the car, a network of dedicated bus-only streets services neighborhoods throughout the city, supported by a comprehensive system of auto-free streets that connect key destinations, open spaces, and the riverfront.
Bike. China has adopted policies that put 6 meters of bike lane on every street. Biking has a rich history in China. After the economic reforms in the late 1970s, bikes became one of the earliest must-haves for Chinese consumers. When the government shut down transportation during the Tiananmen Square protests, bikes were the only means of getting messages out about what was happening. More recently, China's bike-sharing boom has brought more than 2M bikes to city streets.
Connected street networks. Creating a network that allows many routes instead of singular routes and provides many kinds of streets instead of just one is important for a number of reasons. According to the Center for New Urbanism, "good street network designs reduce land consumption, provide greater accessibility through more direct routes, and increase overall network efficiency and reliability through added redundancy. They also affect several factors that relate to building more sustainable communities such as travel patterns, road safety, and public health."
Invest more in transit. For Yuelai, transit adjacency is a key determinant of the land-use makeup and supplementary transportation systems within the city, with the highest densities and mix of uses surrounding the Metro Stations. In addition, a dedicated electric shuttle bus route has been planned along an auto-free street, connecting the Metro stations to surrounding neighborhoods and amenities.
Focus on shifting freeways down the hierarchy of the structure of cities to enable residents to better connect with one another.
What Does this Mean for America?
Since the 1950s when many people in America began moving to suburbs to avoid traffic, noise, and crime rampant in urban areas, sprawl has been a feature of the American landscape. Now, we have large metropolitan areas with low population densities, interconnected by roads. Residents of sprawling cities tend to live in single-family homes and commute to work, school, or other activities by automobile. People who live in large metropolitan areas often find it difficult to travel even short distances without using an automobile, because of the remoteness of residential areas and inadequate availability of mass transit, walkways, or bike paths.
There is a massive amount of literature on how this type of sprawl has negative effects on human health and the environment. And it has become a moral imperative that we try to combat it as much as possible. According to Calthorpe, one way to combat American sprawl is by creating more compact developments and more walkable neighborhoods with integrated, mixed-use environments. This leads to less land consumption, lower carbon emissions, fewer vehicle miles traveled, less air pollution (better health for citizens), and lower household costs (no large lots for single-family homes).
These goals are appealing to many special interest groups, from affordable housing advocates to environmentalists. If these groups joined forces, smart growth policies could have a huge impact on achieving the goals of both.