In response to a number of Supreme Court cases that have complicated what constitutes WOTUS, or the "waters of the United States," the U.S. Environmental Protection Agency (EPA) and the Army Corps of Engineers pursued a rulemaking during 2014 and 2015 to revise the regulatory definition of WOTUS. In May 2015, EPA released the final WOTUS rule which disregarded many concerns expressed by industry, including ACA. The 2015 WOTUS rule gave the federal government jurisdiction over some of the smallest waterways in the country, including authority over smaller bodies of water that EPA doesn't already regulate. Since promulgation, the 2015 WOTUS rule was subject to extensive litigation leading up to the eventual stay of the 2015 rule by the U.S. Court of Appeals for the Sixth Circuit.
On February 28, 2017, President Trump issued Executive Order 13778 which directed EPA and the Army Corps to review and rescind or revise the 2015 WOTUS rule. As a result, EPA and the Army Corps initiated a comprehensive, two-step process intended to repeal (step one) and revise (step two) the definition of WOTUS.
Since then, the agencies issued three rulemakings pertaining to step one of the process that attempt to: (1) repeal the 2015 WOTUS definition, (2) recodify of the pre-2015 WOTUS definition and regulation, and (3) delay the effective date of the 2015 WOTUS rule to provide additional time and regulatory certainty while the agencies complete their two-step process. These efforts were met with legal action by various entities, though, and several district courts ruled that the agencies did not follow proper procedures to delay implementation of the 2015 WOTUS rule. On March 8, 2019, the Trump administration abandoned its bid to use the courts to delay implementation of the 2015 WOTUS rule. This means that the 2015 WOTUS rule will remain in effect for the foreseeable future in more than 20 states across the country (the other states do not have to follow the 2015 rule because of prior legal rulings in their jurisdictions). Additionally, on March 26, a U.S. District Court for the Southern District of Ohio didn't grant an injunction sought by Ohio and Tennessee that would have effectively nullified the 2015 WOTUS definition. According to the judge, those states couldn't substantiate claims that the rule's enforcement would cause irreparable harm to the states.
Despite this setback, EPA and the Army Corps still intend to proceed with their two-step process to repeal and revise the definition of WOTUS through regulatory action. The agencies' June 2018 proposed rule to repeal the 2015 WOTUS rule in its entirety and recodify the pre-2015 regulation is still slated to be finalized sometime in mid-2019. Also, in anticipation of this final rule, EPA and the Army Corps published a proposed rule in February 2019 that formally initiated step two of their process which revises the definition of WOTUS. Of note, the agencies are proposing a baseline concept that "waters of the United States" are waters within the ordinary meaning of the term, such as oceans, rivers, streams, lakes, ponds, and wetlands, and that not all waters are "waters of the United States."
