On December 11, the United States Environmental Protection Agency published on their website the Proposed Revised Definition of "Waters of the United States." The latest draft of guidelines was created in collaboration between the EPA and the Department of the Army and aims to "establish the scope of federal regulatory authority under the Clean Water Act in a more clear and understandable way."

Currently, due to litigation, the 2015 Clean Water Rule (WOTUS) is in effect in 22 states, the District of Columbia and the U.S. territories. The previous regulations, instated in the 1980s, are in effect in the remaining 28 states.

The new proposed update outlines six categories of water that would fall under the WOTUS ruling: traditional navigable waters, tributaries, certain ditches, certain lakes and ponds, impoundments, and adjacent wetlands. They also define what will not count as "waters of the United States," and those include things such as groundwater and prior converted cropland.

There will be a 60 day public comment period after the publication of the proposed guidelines in the Federal Register. As of writing this article, there is no word on when that publication would occur. There will also be an informational webcast on January 10, 2019 and a public listening session in Kansas City, Mo., on January 23. Information on both engagements, as well as more information on the proposed updates, can be accessed by visiting https://www.epa.gov/wotus-rule.