On Jan. 23, 2020, EPA and the Army Corps of Engineers unveiled the Trump administration’s revised “Waters of the U.S. (WOTUS)” rule.  The new definition of federally protected water bodies is far narrower than the 2015 Obama administration rule which dramatically expanded the reach of federal jurisdiction over rivers, streams and wetlands and in turn the scope of waters where NPDES permitting applies, including aerial application of pesticides. NAAA was among thousands of stakeholders that submitted comments in 2017 in support of repealing the 2015 Rule.

In September 2019, EPA and Corps announced the repeal of the 2015 rule, now replaced by the new definitions. The new rule, 340 pages long, states that:

This final rule implements the overall objective of the Clean Water Act to restore and maintain the integrity of the nation’s waters by maintaining federal authority over those waters that Congress determined should be regulated by the Federal government under its Commerce Clause powers, while adhering to Congress’ policy directive to preserve States’ primary authority over land and water resources. This final definition increases the predictability and consistency of Clean Water Act programs by clarifying the scope of “waters of the United States” federally regulated under the Act.

The new definition of federally protected water bodies is far narrower than the Obama administration’s version, as it excludes isolated wetlands and ephemeral streams that only flow after a heavy rainfall.

In light of earlier Supreme Court opinions, the key point of dispute among stakeholders is how the agencies should deem a marginal water body federally protected if there is a “significant nexus” between it and another larger body of water that is clearly protected.

Litigation over the new rule, especially the interpretation of “significant nexus,” is expected to be filed by stakeholders who support the earlier EPA definitions contained in the 2015 rule.