News | Notices | Events

Waters of the United States (WOTUS) Comments

The Environmental Protection Agency (EPA) and U.S. Army Corps of Engineers (USACE) are revising the current definition of a Waters of the United States (WOTUS) through rulemaking | View >

There have been multiple rulemakings regarding WOTUS, and ADEQ has historically commented on these revisions, which have been conducted during the last three federal administrations.


The Clean Water Rule (CWR) became law in August 2015, but a preliminary injunction issued by a Federal District Court halted the rule’s implementation in Arizona. Due to the legal stay, Arizona continued regulating per the pre-2015 guidance released by the EPA and USACE. The CWR was repealed in September 2019 | View State Comment Letter >

The Navigable Waters Protection Rule (NWPR) became law in June 2020. Arizona began implementation of the NWPR until August 30, 2022, when the rule was vacated by a federal court. This vacatur resulted in Arizona returning to the pre-2015 guidance | View State Comment Letter >

In December 2021, the EPA and USACE proposed WOTUS “Rule 1” to put back into place the pre-2015 definition of WOTUS and included language to reflect consideration of Supreme Court decisions | View State Comment Letter >