Environmental law did not begin with enactment of the National Environmental Policy Act (NEPA) in 1969. Nor did it begin when Massachusetts adopted the first state wetland protection statute in 1963 or California adopted the first controls on air pollution from automobiles. It did not begin when the federal government established Yellowstone National Park in 1872 either.
Environmental law may have begun in 1610, when a landowner brought legal action against a neighboring pig sty, objecting to the fumes and odors it produced. The sty owner objected that the landowner's sensitivities should not take precedence over his productive activity, but the court was not convinced, recognizing that each landowner only has the right to make use of their property in such a way as not to infringe upon the right of others to do the same, and that this meant nuisance claims against polluting activity could proceed. This decision was not the first articulation of this principle, but it appears to have been the first reported case in which it was enforced.
What we think of as environmental law today--sprawling statutes authorizing expansive regulation of economic activity--is a relatively new phenomenon. The first environmental statutes were efforts to reinforce and supplement nuisance law, as well as to provide greater clarity and predictability as to what sorts of activities would be allowed where (e.g. whether coal-burning could occur in densely populated areas). It was not until much later that policymakers concluded environmental protection required the erection of an administrative state and prescriptive regulations supplanted tort law as the front line of environmental defense.
