An International Review of Eco-City Theory, Indicators, and Case Studies
This report is intended to answer the question: "What international experiences with ‘eco-cities' can help the central Chinese government evaluate the performance of Chinese cities that pursue ‘low-carbon' urban development?" To answer this question, we reviewed the literature on eco-cities and closely related concepts, surveyed performance indicators used to evaluate sustainable urban development around the world, and compiled case studies of exceptional eco- and sustainable cities.
Part I of this report describes our review of urban planning, architecture, urban studies, and civil engineering literature. The goal of this review was to determine how theorists and advocates have used the term "eco-city" and similar concepts throughout the past 150 years and to identify other terms and concepts used to describe eco-cities and characteristic eco-city features.
Part II of this report looks at the performance indicators that governments, institutions, academics, and citizens are using to evaluate the sustainability or "green" performance of urban developments. This section of the report identifies, to the extent possible, themes and indicators that are common among the indices used to evaluate cities.
Part III presents case studies of cities that are viewed internationally as leaders in instituting progressive eco-city policies and technologies.
The central finding of this research is that there is an array of opportunities to combine existing theory to develop a system that the Chinese government can use to evaluate eco-cities, but the definitions and indicators used must be tuned to the Chinese context and specifically to locally defined policy goals, to the extent that local administrations have the power to define these goals.
Our literature review reveals that there no consensus on a definition of eco-city, nor are there scientifically based criteria for evaluating eco-cities. The term "eco-city," and similar concepts such as "green" and "sustainable" cities, have evolved over time concurrent to the development of the understanding of social change and mankind's impact on environmental and economic health. The terms "green city," "sustainable city," and "eco-city" will likely continue to evolve as best practices for economic sustainability and social health evolve. In addition, evaluating a city's relationship to and impact on its environment, inhabitants, and the market is complex from a theoretical standpoint and challenging because data on eco-cities vary and cannot be easily compared. In sum, "eco-city" and similar terms are used subjectively. For this concept to usefully inform Chinese policy, eco-city goals that are specific to China should be developed.
The eco-city concept and other similar ideas originated during the late industrial revolution in response to the poor health and living conditions of urban populations at the time. The eco-city idea has evolved, mostly in the United States and Western Europe; we have identified five forms this idea has taken, which have overlapped through time and are often additive to previous forms: 1) integrating an agrarian settlement mode into city-like settlements to increase health and reduce social discord related to poverty; 2) protecting human and local environmental and ecosystem health; 3) protecting global environmental health; 4) integrating broad concepts of social health, such as economic and social equity; and, most recently, 5) incorporating climate change resilience and technological advances. This evolution has produced a diversity of concepts, many of which have been integrated into eco-city theory by proponents despite a lack of consensus on the exact detail of each or the priority of strategies to be pursued. Broadly, an eco-city should incorporate plans, measures, technologies, and operational strategies to increase all aspects of environmental, social, and economic health; narrowly, these goals should be accomplished primarily by efforts to conserve natural resources, reduce fossil fuel use, increase density and reduce automobile use, reduce and recycle waste streams, integrate nature into cities, shift the economy toward the service sector and high-value added technology creation, build diverse spaces that offer value to all population subgroups, and actively seek and support community involvement in city improvement efforts. Although the definition of an eco-city varies, systems of evaluating eco-city performance have, during the past 20 years, moved from reliance on qualitative principles to reliance on quantitative performance metrics.
Because the term "low-carbon eco-city" has only recently attained popularity in China and is not used elsewhere, there are no existing indicator systems to measure the performance of such a city. However, there is some high-level consensus on the types of phenomena that should be measured in evaluating sustainable, green, eco-, and similarly labeled cities. All indicator systems measure performance related to energy and climate change. Fewer, but still a majority, measure air quality and land use impacts. Even fewer, but still a majority, measure water quality and social health impacts. Waste, transportation, and economic impacts are least commonly measured, but nevertheless are measured by a majority of indicator systems. Despite some consensus on the most important general categories to be measured, there is little consensus about the priority issues to be evaluated in each category. There is also little agreement on the methodology by which indicators for each of these areas should be chosen other than relying on data that are already available and on expert opinion regarding what indicators can best be used to measure progress. Threshold benchmarks are not commonly used, and there is little agreement on how indicators or indicator categories should be weighed against each other in forming an aggregated score that could be assigned to a city if a single summary indicator is desired.
Five case studies are examined in Part III of this report: Stockholm, Sweden; New York City, New York, U.S.A.; San Francisco, California, U.S.A.; Portland, Oregon, U.S.A.; and Vancouver, British Columbia, Canada. These case studies show that even geographically and economically similar cities in Western Europe and North America approach sustainability and the eco-city concept from different perspectives. These perspectives are influenced by the relationship between each place and its population as well as by physical and political limitations on each city's government. Although the case studies are impressive, the question remains whether the efforts they describe are sustainable and whether their lessons are applicable to the very different geographic, social, economic, and political contexts in China.
Overall, we find that the lack of consensus on the definition of eco-, green, and sustainable cities is driven by a lack of empirical data from long-term case studies as well as by the fact that efforts to develop and evaluate such cities are embedded in political and social goals and priorities.
We conclude that the development of a low-carbon eco-city evaluation scheme in any jurisdiction should begin with an examination of the goals articulated in that region's most recent urban development plans. These goals should then be expanded based on consideration of common indicator categories used internationally and examples of successful planning models. This will enable the region to learn from and add to international policy and technology development efforts. The process of developing eco-city plans and metric systems will be incremental as cities tailor policies and practices to specific local circumstances and changing external factors such as technological developments and economic changes.