Can a new type of “gated community” reverse China’s ecological debacle?
When I asked one of my chinese hosts to give me a tour of his city’s best new housing project, I never imagined it would inspire a Berkeley team to propose revolutionizing how the Chinese develop their new communities.
We set out from the Urban Planning and Design Institute’s offices in a black diplomatic car, whose siren I quickly learned allowed us to exercise authoritative traffic privileges. Our route out of metropolitan Tianjin, China’s third largest city, took us along a major arterial corridor to the northwest, which was clogged with traffic of a chaotic type unmatched in the U.S. Intersections, even though signalized, presented a terrifying game of “chicken.” Cars, trucks, and buses wove through an equal number of bicyclists (often with multiple passengers or goods) and pedestrians. The dust and pollution were so intense that most bicyclists wore facemasks. With siren blaring, we sped along the shoulder past what appeared to be an unending series of developments, including a new college campus, high-tech office parks, and multiple high-density housing developments. As far as the eye could see, the entire landscape seemed under construction.
The scale of infrastructure construction to support this kind of hyperdevelopment in China is hard to imagine. It is estimated that China builds more than fifty 300-megawatt coal-fired power plants per year. California has only built 36 in the last five years. China is undertaking the largest road construction program in the world, equivalent to the U.S. Interstate highway system begun in the 50s. The capital and material costs of this effort are increased by the fact that in most areas of infrastructure China is playing catch-up. For example, an estimated 60 percent of existing sewage is dumped into rivers, untreated. Not only is the cost of building sewer mains and centralized treatment plants for new development staggering, but also, without cleaning up the existing sewers, the polluted rivers magnify the challenge of delivering sanitary drinking water. Some urban planning scholars question whether the current rate of development is economically sustainable, but if it is, it is estimated that China will double the size of its built environment in the next 20 to 30 years—the equivalent of building two new Great Britains.
When the pollution and CO2 emissions from the congested arteries are combined with that from the power plants required to meet the energy demands of new development, the impact on both China’s public health and on global climate change presents major challenges for the years ahead. Four-fifths of China’s largest cities have unacceptable air quality, resulting in more than 600,000 premature deaths from asthma, emphysema, and lung cancer. Currently it is estimated that China is responsible for 25 percent of the world’s CO2 emissions (the U.S. is at 30 percent). At its current rate of development, China is projected to surpass the U.S. in the next few years.
Mounting scientific evidence has shown conclusively that the current cycle of global warming is not natural but attributable directly to man-made CO2 emissions; and while the projections vary in magnitude (from 2–10˚ C), the projected impact of global warming on the earth’s natural systems is catastrophic. On balance, the question becomes: Can the world dramatically cut back its CO2 emissions to avoid these catastrophic scenarios? The responsibility falls on the U.S. and China to show the way. Fortunately, China has recognized this challenge and it has been seeking the best urban planning and design advice and concepts from around the world. Our Berkeley team was invited by the Tianjin Urban Planning and Design Institute to assist the city of ten million residents in developing principles and prototypes for compact, transit-oriented, commuter gateway neighborhoods promoting efficient land use, and relying more on public transportation and bicycles and less on cars. With half the population living outside Tianjin proper, the city recognized that it was necessary to build a public transit system of subways, light-rail, and connecting buses in order to avoid the traffic congestion afflicting Beijing and Shanghai. Having completed two of seven planned light-rail lines, the city sought advice on how to guide development around the station stops. The College of Environmental Design responded by forming an interdisciplinary team of faculty and students from each of its three departments—Architecture, City and Regional Planning, and Landscape Architecture and Environmental Planning—to come up with design proposals that address critical real-world problems. The Tianjin Urban Planning and Design Institute funded the semester-long project, which included a week-long visit to the Chinese city followed by analysis and preliminary designs. In Berkeley, three Chinese scholars joined the 15-member team to help inculcate the project with the nation’s cultural and practical realities. But what unfolded during the semester was largely due to the impact of what we found during our Chinese tour.
At our destination, we passed through an entry gate, where we were saluted by two uniformed guards, and proceeded to an elegant marketing showroom complete with a scale model of the entire development and elaborate models of each unit type for sale. The plan was based on repetitive blocks of townhouses and flats; their designs were of high quality, similar to what might be seen in Holland, Germany, or Scandinavia. Vehicular and pedestrian access to the housing units was provided by uniform street grids with limited parking at the units and overflow parking along a fence forming the community’s perimeter. Much attention had been paid to landscape design. Streets, sidewalks and pathways of various paving materials were shaded by an array of trees. The project also featured several small parks, schools, a small central commercial area, recreation facilities, and a lake with multiple high-rise residential towers overlooking it.
I quickly estimated the density at approximately 75–100 units per acre (San Francisco averages approximately 35 units per acre). As I explored the project with my Chinese host, who was justifiably proud of its design quality, it dawned on me that what was being sold was a gated, privatized urbanity—a carefully controlled development with an urban theme but without any of the nitty-gritty reality of the city. Moreover, the gated entry gave residents a sense of belonging to a privileged community. It was hard not to interpret this as a form of social segregation.
Our hosts showed us multiple examples of the same model throughout the city-gated superblocks within a grid of new arterial streets at approximately one-mile or 1.2-mile intervals. One opportunistic developer was already in the process of building a gated superblock on the site where we were asked to explore transit-oriented development. Immediately, we became concerned. The project under construction effectively served only the residents within the gated community, blocking pedestrian and bike access to the light rail station for anyone else. Residents of other developments would be forced to walk or bike a mile or more to get around the first development. I wondered: Did our Chinese hosts not see this contradiction? Were they looking for alternatives?
We also knew Chinese gated superblocks comprise the largest part of China’s overall development efforts, which are among the most ambitious construction undertakings in the history of the world. The Chinese are building 10–15 gated superblocks every day, equal to 10–12 million housing units per year (10 times the U.S. average). The process benefits from a clear definition of roles. The city builds the new system of arterial roads and then sells the superblock development rights to a developer, who is responsible for constructing a prescribed number of housing units at specific unit sizes, and for providing all internal community facilities and infrastructure, including commercial shopping and offices, schools, recreation facilities, parks and landscaping, and all internal roads, sewage lines, water and power distribution. The process depends on the support of a centralized infrastructure of power plants (usually coal fired) and electric power lines, sewage treatment plants (including sewer mains), and a sanitary water supply provided by the city or provincial utilities. The developer just “plugs in” to these services.
While highly efficient at providing housing, an array of negative consequences has emerged from China’s gated superblock model. With a single entry/exit, and barriers to those outside the immediate gated community, the pattern almost guarantees that people will be forced to use cars on trips that are now walked or bicycled by 80 percent of the residents. As vehicular traffic grows, streets will become congested, creating corridors of pollution similar to what we saw on our tour. This traffic pattern will also remove people from the pattern of streets and alleys that has supported the rich and diverse urban culture of traditional Chinese cities for millennia.
Preliminary calculations revealed that 30 percent of China’s CO2 emissions could be directly attributed to the construction, transportation and power generation required to build and operate these superblocks. The Berkeley team quickly realized that by developing principles and prototypes for transit-oriented neighborhoods, it could address half the problems of the impact of the car.
But what if we thought bigger? What if our designs could also generate all the community’s energy by employing renewable sources on site, treat all wastes, and provide most of the water? If China’s fundamental unit of development could become resource self-sufficient (i.e., carbon neutral) in its operation, and if it could replicate and spread throughout the world, this would be a major force in reversing global climate change.
With this larger goal in mind, the Berkeley team spent the semester creating an entire system—including, but beyond transit-oriented neighborhoods—to consider all potential sources of energy and waste flows that might make the neighborhood resource self-sufficient. First the team tackled the challenge of making the project transit friendly. They came up with a system of designated streets and blocks with mid-block greenways reserved for pedestrians and bicycles. These greenways connect to a network of parks leading directly to transit stops. In this way pedestrians and bikes are given a privileged, independent route to transit. At the same time all the streets are carefully designed to accommodate bikes and pedestrians; but by creating an independent system, the bicycle and pedestrian congestion at intersections is greatly reduced. With such a walking and bicycle friendly neighborhood, dependence on the car as the primary mode of transit can be reduced and the vehicle miles traveled reduced, with CO2 emission reduced as well by 75 percent. Car ownership (an estimated 12,000 to 14,000 cars are being added to China’s streets every day) is not discouraged, but the car becomes a convenience for recreation and selected uses, rather than a necessity.
The team then focused on how to supply energy for a high-density, superblock community. Conservation and implementing designs that best responded to the climate appeared to be the most cost-effective strategy for reducing both energy consumption and demand. By careful application of passive solar design principles and natural cooling (using shading and ventilation), we determined that heating loads could be reduced by 80 percent and cooling loads by 60 percent. The challenge became how to provide the back-up heating and cooling, and the electricity for lighting and appliances. A combination of renewable strategies was discovered. By putting photovoltaic panels (PVs) on the roofs and also using them as sun shades for south-facing windows, we calculated we could deliver approximately 40 percent of the electric load to energy efficient appliances. Adding wind conversion machines atop tall buildings (approximately 20 to 30 per neighborhood) would provide an additional 40 percent of the electric load. The balance of the electric load, plus gas for cooking and domestic hot water, could be provided by biogas generated from a combination of sewage, food wastes, and green wastes from the local landscape, trees, and urban agriculture. In this model, the high density of housing (150 units to the acre) became an environmental asset by providing the concentration of waste required to produce sufficient energy. An integrated system was also preferable in that it could spread the workload and could be sized for optimum cost effectiveness; no energy storage was required.
In addition to transportation and energy, water supply and wastewater treatment were equally important to these newly-designed communities. The buildings could collect all rainwater in cisterns for supply, and recycle “gray” water for low flush toilets. Ground water would be either absorbed directly on site or collected for landscape irrigation—there is no storm water runoff. Wastewater produced when bacteria digest and decompose biological matter in an oxygen-free environment (producing methane as an energy source) is treated naturally and recycled also for irrigation. This water system could provide as much as 75 percent of the needed water.
The team also restricted impermeable paving materials to the travel lanes of the streets. All parking areas, sidewalks and courtyards were proposed to have porous pavers. By absorbing storm water run-off on site, the design eliminates the cost of storm water piping, and, more importantly, it provides natural irrigation and soil aeration, making it possible to plant a more extensive “urban forest.” Providing extensive tree coverage for the streets, sidewalks and parking areas has a triple environmental benefit. First, the shade in the summer reduces the “heat island” effect by as much as 3 to 10 degrees; not only making the public realm more comfortable but also reducing air conditioning loads by 10 to 15 percent. Second, by selecting appropriate species of trees and planting and harvesting them in sequence, all the CO2 generated on the site can be absorbed. Finally, the trees, clippings and prunings provide additional biomass for the biogas digesters.
One of the most important parts in the whole system is the role of the streets, courtyards, greenways, and parks—the landscape—in enhancing environmental quality. By employing the most advanced “green” design principles, only 40 percent of the land is covered by buildings, the rest, 60 percent, is public and semi-public open space.
While the streets, sidewalks and parking areas constitute a fifth of the land coverage, the remaining mid-block courtyards, greenways and public parks are double that figure. Half of the larger landscape can be used for recreation and at least half of it for local, organic community gardens, providing as much as 30 percent of the produce needs of the neighborhood. As with the “green” streets, the green wastes from the urban agriculture and urban parks contribute significant biomass to the biogas digesters. By conceiving of the landscape, infrastructure, and buildings as a whole system design, the neighborhood becomes as self sufficient as possible.
As the project progressed, the Berkeley team became more and more excited by the potential for the whole system design concept to be a real breakthrough, to be a reproducible model for sustainable development throughout China and the developing world. The buildings are platforms for producing energy from renewable sources such as wind and sun. Sewage is not treated and dumped, but processed into energy, fertilizer, and water for irrigation. The landscape is more than eye pleasing; it is a multi-functional contributor to the systems. There is little or no waste, and all energy is generated on site. Most importantly, the neighborhood becomes essentially a self-sufficient unit, a circular system. It does not require the construction of expensive new power plants, new sewage treatment and water supply outside the system.
But just as the team became more convinced that the design made environmental sense, difficult challenges emerged.
The new design requires a radical transformation in the development process. In addition to constructing housing units, the developer has to build a comprehensive, on-site utility system of energy production, water supply, and sewage treatment, which is beyond the developer’s traditional scope of work. It requires getting approvals through government agencies that are narrowly proscribed and not accustomed to thinking across their jurisdictions. Most importantly, it requires design and construction professionals to share responsibility and to work collaboratively, to which they are unaccustomed. It requires paying 15 to 20 percent of the costs up front. Even though the life cycle costs are significantly less than the cost of constructing new centralized utilities, the question becomes: Who owns, operates, and maintains the system, and how are they compensated for the service? Some models exist for funding and operating on site systems, but none is as comprehensive and integrated as the one proposed. (Since China is behind in providing centralized infrastructure, many developers have had to provide selected utilities, usually sewage treatment, on site). Despite these institutional and bureaucratic challenges, the economic and environmental benefits of the proposed system offer creative business opportunities for the neighborhood and the city.
Still, the design team realized that the hardest obstacle to overcome would be the social and cultural demand for a “gated” identity. The concept of a gated community is ingrained in Chinese consciousness by the Forbidden City, the emperor’s own gated community. The traditional Chinese courtyard house, the hutong, is a form of gated community for families, with its walled precinct, gated entry and assembly of buildings around the courtyard. We’ve tried to provide a similar gated identity, but not at the superblock scale, nor at the scale of individual units, but at an intermediate, urban block scale. The system has the advantage of keeping select streets open and walkable to transit and services while creating semi-private, gated courtyards in the middle of blocks. The concept has a further advantage. The blocks can be designed to accommodate between 100 and 300 families, a scale that sociologists argue is a manageable size for knowing your neighbors and promoting a sense of community.
Even though the challenges are daunting, the inherent qualities in the design provide many opportunities and rationales for overcoming them. The upside potential, economically, socially—and especially environmentally—is almost irresistible. What is needed is proof that such an integrated design can work. Fortunately, the Gordon Moore Foundation has recognized this fact. It has made a multi-year, multimillion-dollar grant to Berkeley’s Institute for the Environment (B.I.E.) to enhance worldwide capacity for sustainable urban development. The Sustainable Neighborhood Project is part of the grant.
With a workable prototype, China’s unique top-down/bottom-up planning and development process has the capacity for rapid deployment of such a model. The central Bureau of Planning and Reform would approve the model as fulfilling the goals of China’s 11th Five Year Plan for conversion to a “circular economy.” The Ministry of Construction would promulgate the detailed design guidelines, creating a standard template for design approval. Finally, the mayors, who are evaluated each year by the party, would be measured in part by how extensively they had applied this basic unit of development. Through this process, the potential for replication is almost unlimited.
Currently, several cities are vying for the opportunity to build one of these prototypes, resource-self-sufficient, transit-oriented neighborhoods. Paradoxically, while China is presently the source of some of the planet’s most serious environmental problems, it also has the greatest capacity for change.
Harrison S. Fraker Jr. is dean of the College of Environmental Design.
From the September October 2006 Global Warning issue of California.