Their authority comes from the 1972 Clean Water Act and it initially defined WOTUS as those bodies of water that were considered “navigable” and that they be protected. Ever since 1972, the term “navigable waters,” has expanded due to regulation, interpretation, and court rulings to cover tributaries, small water bodies, and wetlands or partial adjacent to such waters. As the agencies interpretations continued the expansion, they were challenged, and the U.S. Supreme Court reigned in the agencies.
In response to Supreme Court’s decision, the Obama Administration promulgated the expansive “Clean Water Rule: Definition of ‘Waters of the United States’” rule in 2015. The rule greatly expanded the definition of “navigable waters” and among many provisions, one of them included land that could be as far away as 4,000 feet from a waterway. Many States and industry groups filed suit against the rule injunctions were issued against it their states, thus creating regulatory deadlock.
To resolve the conflict and provide better clarity, the Trump Administration proposed a replacement regulation to the one issued under the Obama Administration. The proposed new rule streamlines rather than adds categories of waters. Under the rule, there six categories of water bodies that would be regulated with clear delineations as to when they would be regulated based on their contribution to a traditional navigable waterway. If a water body does not fall into one of the categories, it would be exempt from regulation. It could still be regulated by a different federal or state regulation.