Site Planning and Design Handbook

Abstract

The activities of human beings have had and will continue to have a significant impact on the earth’s environment. It has been said that 60 percent of the earth’s land surface is under the management of people, but 100 percent of the earth’s surface is impacted by the practices of that management. Paul Erhlich (1994) used the formula I PAT, or impact population affluence technology, to illustrate the relationship of the number of people, the per capita rate of consumption, and the economic efficiency of consumption. Thus, for example, although the United States may have more efficient and cleaner technologies than some nations, its rate of consumption afforded by its relative affluence may offset those efficiencies. In contrast, although China has a high population, its relative low levels of affluence and technology may offset its high population. In both countries, however, the environmental footprint is clearly significant. In 1987 the Brundtland Commission published Our Common Future, which said that to avoid or at least minimize the environmental impact of human behavior, it is necessary for society to adopt a sustainable approach to development. “Sustainability” was defined as “meeting the needs of the present without compromising the ability of future generations to meet their own needs.” In February 1996 the President’s Council on Sustainable Development (PCSD) published Sustainable America—A New Consensus for Prosperity, Opportunity and a Healthy Environment for the Future. The PCSD identified 10 goals, but the first 3 could be viewed as encompassing them all: health, economic prosperity, and equity. Equity refers to social equity (equal opportunity) and intergenerational equity (equity for future generations). To meet the challenges of sustainability, we need to change our behaviors and adapt to a paradigm of economic prosperity, social equity, and environmental sustainability. Unfortunately, these goals have traditionally been viewed as