In 1920 the Pennsylvania Railroad sued several small coal companies over water pollution. The lawsuit, ultimately decided in the railroad's favor, overturned an earlier Pennsylvania court decision that granted a property right to pollute, and, more important, now represents a major transitional period in American water policy history. The period marked the end of water policy generated from court decisions and case law, and the beginning of an era dominated by legislative statute and agency interpretation. With the Pennsylvania case, the impacts of nineteenth-century court decisions that sanctioned pollution to encourage business waned as concern for the nation's public health demanded more expansive attention, and industry itself began to experience excessive costs from corrupted water resources. In Pennsylvania and elsewhere, lawmakers attempted to institute a new strategy for economic interest in harmony with efforts to improve environmental quality.