Calling it a disaster, President Donald Trump signed an executive order last week to dismantle the controversial Waters of the United States rule.

Trump instructed the Environmental Protection Agency and the Army Corps of Engineers to review and reconsider the rule, also known as WOTUS or the Clean Water Rule. But he did not mention that rolling back the provision could put at risk the health of 117 million Americans, the well-being of plant and animal species including endangered ones and the protection of critical habitats. The economic risks could also be significant.

The story of the Clean Water Rule dates back to a sweltering summer day in 1969 when Ohios Cuyahoga River, a tributary of Lake Erie, became so polluted with sewage and industrial waste that it burst into flames .

The disaster sparked an environmental revolution in the U.S. It helped lead to the establishment of the EPA in 1970 and the passage of the Clean Water Act in 1972, which gave the federal agency the authority to limit pollution in navigable waters.

The law was a game-changer for Americas large water bodies, including the Cuyahoga, which went from burning to gleam[ing] by the late 1980s.