Concerns over the state of water quality in the 1960s and 1970s spurred environmental action nationally and served as major motivating factors for the environmental laws and regulations that were passed in the 1970s. The 1969 fire on the Cuyahoga River in Cleveland, Ohio, the result of accumulated oil, waste, sewage and debris, caught national attention and brought about pollution control measures such as the Clean Water Act. In the same year, Lake Erie was described as “dead” due to its polluted state, low oxygen level and high algae content. In response, the National Broadcasting Company (NBC) televised the documentary “Who Killed Lake Erie?". While combustibles, pathogens, visible refuse, and dangerous chemicals were addressed in early water regulations, concerns have shifted to chemical and microbial pollutants and seasonal climatic events that threaten the use of water bodies, and ultimately how they are valued directly and indirectly. Today, the concern is not whether a water body is “dead” or “alive”, but on developing accurate measurements of the costs and benefits of water quality changes and improvements.
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