Ocean disposal of society's waste got its start indirectly long before the Agricultural Age when nearby streams, lakes, and estuaries were useful as waste repositories. As civilization moved to the coastal zone and navigation began in earnest, the oceans were viewed as even a larger waste repository. Early civilizations were located adjacent to bodies of water for sources of food, irrigation, drinking water, transportation, and a place to dispose of unnecessary items. Historically, the disposal of wastes into water by humans was universally practiced. It was a cheap and convenient way to rid society of food wastes (e.g., cleaned carcasses, shells, etc.), trash, mining wastes, and human wastes (or sewage). The advent of the Industrial Age brought with it the new problem of chemical wastes and by-products: These were also commonly disposed of in the water.

A trash-strewn beach. (©Claude Charlier/Corbis. Reproduced by permission...