In April 2020, the EPA and the Department of the Army (“the agencies”) published the Navigable Waters Protection Rule that revised the previously-codified definition of “waters of the United States” (WOTUS). The agencies are in the process of revising the definition of WOTUS to include the waters defined by the familiar regulations that were in place prior to the 2015 WOTUS rule, with amendments to reflect the agencies’ determination of the statutory limits on the scope of the “waters of the United States” informed by Supreme Court precedent, the best available science, and the agencies’ experience and technical expertise. The agencies also intend to consider further refinements in a second rule (Rule 2) in light of additional stakeholder engagement and implementation considerations, scientific developments, litigation and environmental justice values. This effort will also be informed by the experience of implementing the pre-2015 rule, the 2015 Clean Water Rule, the 2020 Navigable Waters Protection Rule, and Rule 1.