After signing the final rule repealing the existing definition of “waters of the United States” (WOTUS) on September 15, EPA and the Army Corps of Engineers published the repeal rule in the October 22 Federal Register. The rule, titled "Definition of Waters of the United States - Recodification of Pre-Existing Rules,” reinstates pre-2015 regulations for what is deemed a water of the United States starting December 23, 2019.
This has been described as “step 1” in a two-step process for replacing the WOTUS rule implemented by the Obama administration in 2015. Step 2 involves the finalization of a new definition for WOTUS, which the Trump administration proposed earlier this year. EPA did not specify when the final rule for the new WOTUS definition will be issued, but it is expected by December of this year according to the Trump administration’s most recent Unified Agenda of Regulatory and Deregulatory Actions.