President Donald Trump is preparing to take a first step toward dismantling Barack Obama's environmental legacy.
Trump on Tuesday is expected to sign an executive order instructing the Environmental Protection Agency to begin reviewing and rewriting the 2015 Waters of the United States rule, which Trump previously promised to eliminate.
The rule clarified (and arguably expanded) the Environmental Protection Agency's ability to regulate pollution in major bodies of water as well as the smaller streams and tributaries that flow into them.
The rule was created under the authority granted to the EPA by the 1972 Clean Water Act, and it followed two Bush-era Supreme Court cases that created some confusion about how much the federal government could regulate activities around streams and other small bodies of water. The Waters of the United States rule was intended to clarify the EPA's reach by designating a comprehensive list of waterways that are subject to regulation from the agency.
Accounting for about three-fifths of all American waterways, the rule granted the EPA authority over a broad swath of US rivers, lakes, and ponds, and it limited how many of those were eligible for individual case-by-case analyses.
That flipped an earlier dynamic on its head: No longer would the agency swoop in when a waterway was being polluted and assert its authority to protect it. Instead, any person or group wishing to make use of a waterway subject to the rule would have to first appeal to the EPA for a permit.
Many landowners, especially farmers, have objected to the rule, which in some cases required them to apply for permits to use water that had already been in use on their land for years. Opponents also pointed out that some waterways covered under the rule were not always wet.
This resistance led to legal challenges, and the rule was not fully implemented because of a stay issued by the Sixth Circuit Court of Appeals in 2015.
Trump's executive order would be the first to attack a major line item in Obama's environmental legacy (with the exception of Trump's removal of blocks on several proposed oil pipelines). Other reversals of Obama-era environmental regulations have come from congressional actions.
The expected order won't immediately do away with the rule, however — instead, it simply formalizes the administration's intent to roll back the regulation.
As The New York Times points out, the order would have about the same weight as a phone call to the EPA's administrator, Scott Pruitt. Actually taking the rule off the books could take years.