Legal training, political savvy, and scientific information about human impacts on other species can combine to stimulate legislation that helps protect the environment. In 1970, President Richard Nixon created the Environmental Protection Agency by executive order. Since that time, Congress has passed several laws to combat some of the worst environmental problems in the United States. Following are a few major pieces of environmental legislation:
∙ The Endangered Species Act of 1973 requires that the U.S. Secretary of the Interior identify threatened and endangered species. The overall goals are to prevent extinction and to help endangered species recover their numbers. Since the act was implemented, nearly 700 species of vertebrate and invertebrate animals and nearly 900 species of plants and lichens have been classified as threatened or endangered. Only a few dozen species have been removed from the list because they have either recovered or become extinct, or because new information revealed that their populations are larger than had been thought.
∙ The Clean Air Act, passed in 1970 and amended several times since, sets minimum air quality standards for many types of air pollutants. Since 1970, emissions of nitrogen and sulfur oxides, lead, carbon monoxide, particulates, and other pollutants have declined, leading to significant improvements in regional air quality.
∙ Among other provisions, the Clean Water Act of 1972 required nearly every city to build and maintain a sewage treatment plant, drastically reducing the discharge of raw sewage into rivers and lakes. The 1987 Water Quality Act regulates water pollution from industry, agricultural runoff, and overflow from sewage treatment plants during storms, and runoff from city streets. Many of the nation’s surface waters have recovered from past unregulated discharge of phosphorus, other nutrients, and toxic chemicals.