Yesterday, Donald Trump issued an executive order seeking to roll back the Obama administration-era Clean Water Rule (also referred to as the Waters of the U.S. Rule). Put forth by the Environmental Protection Agency and the Army Corps of Engineers in 2015, it was an attempt to clarify years of confusion over which “waters of the United States” are protected from pollution under the Clean Water Act.

“Agencies and the courts agree that this term includes ‘navigable waters,’ such as rivers and lakes,” wrote Reagan Waskom, director of the Colorado Water Institute at Colorado State University, and David J. Cooper, senior research scientist and scholar professor at Colorado State University. “It also covers waterways connected to them, such as marshes and wetlands. The central question is how closely connected a water body must be to navigable waters to fall under federal jurisdiction.”

At the heart of the rule is the question of “how far upstream federal protection extends,” Waskom and Cooper wrote. The 2015 ruling, which resulted in the protection of more waterways, was hailed by environmental groups but decried by industry, including agricultural groups.

The response to yesterday’s executive order from Trump drew similarly split reactions.

“By attacking the Clean Water Rule and fundamental protections under the Clean Water Act, the president is putting the drinking water of 117 million people at risk, demonstrating that he puts the interests of corporate polluters above the public’s health,” said Earthjustice president Trip van Noppen.

“The people of the American West want clean, healthy rivers, not a return to the days when rivers in America caught fire and were severely polluted and dead,” said Gary Wockner, director of Save the Poudre and Save the Colorado. “Trump’s attack on clean water and healthy rivers will be met with a fierce, lengthy battle in the courts as well as the court of public opinion.”

Wockner told Water Deeply that, “This is the biggest and most rabid anti-environmental order that [Trump] has issued so far. The environmental community who represents the vast majority of the American public in wanting clean water and healthy rivers is going to challenge him immediately and aggressively.”

Wockner said that poll after poll shows that Americans want clean water and healthy rivers. “No one wants dirty, polluted water, except the industries that make extraordinary amounts of money via polluting our water,” said Wockner.

Meanwhile, agriculture groups praised Trump’s order. “We appreciate the Trump administration’s commitment to reducing regulatory burdens for America’s farmers and ranchers,” said National Corn Growers Association president Wesley Spurlock.

American Farm Bureau Federation president Zippy Duvall said, “The Environmental Protection Agency failed to listen to farmers’ and ranchers’ concerns when drafting the rule and instead created widespread confusion for agriculture. Under the rule, the smallest pond or ditch could be declared a federal waterway.”

Farm organizations have contended the rule would place unfair burdens on them by subjecting irrigation ponds and ditches to protection. The EPA has contended however that, “The rule limits protection to ditches that are constructed out of streams or function like streams and can carry pollution downstream. So ditches that are not constructed in streams and that flow only when it rains are not covered.”

Legal experts have pointed out that whatever the impact of Trump’s order, it won’t be happening quickly. The Clean Water Rule itself hasn’t been implemented as the U.S. Court of Appeals for the 6th Circuit put a stay on it after legal challenges.

“An executive order purporting to roll back the rule is nothing more than a paper tweet – it will have no immediate legal effect,” said attorney Thaddeus Lightfoot. “The only procedural method for rescinding or revising the rule is through notice and comment rulemaking under the federal Administrative Procedure Act, which could take years.”

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