New WOTUS rules: More clarity but still muddy

Updated: Aug 30, 2020

The Trump Administration’s latest Waters of the United States (WOTUS) rules, proposed last month, are designed to clarify federal control over the nation’s aquatic system but still leaves significant room for interpretation. Landowners should be cautious in presuming that the rule will provide an easier path to obtain permits.


Last December, the Environmental Protection Agency (EPA) and Army Corps of Engineers proposed to limit federal control to only wetlands and tributaries that directly connect to flowing streams and rivers. This rule is a dramatic reversal of the Obama Administration’s 2015 WOTUS rules, which based federal jurisdiction on finding an ecological connection to streams. Those rules reflected Justice Kennedy’s “significant nexus” opinion in the 2006 Rapanos case.

The new proposal implements Justice Antonin Scalia’s Rapanos opinion based on hydrology and not ecology. As discussed in prior blogs  (see here and here), litigation on this issue has exploded in recent years as environmental groups, state and local governments and industry have fought over the extent of federal control. The Obama Rule has already taken effect in 23 states and the District of Columbia but is barred in 27 states – a chaotic situation making it difficult for landowners to know whether they need to obtain federal Clean Water Act permits for such actions as energy development and homebuilding.

Obama Admin. WOTUS rules are in effect in 23 states + DC

The new rules make key changes to the 2015 rules. Importantly, the new rules drop the “significant nexus” standard by regulating only those relatively permanent waters including:

  • Traditional Navigable waters (TNW),

  • Tributaries that contribute perennial or intermittent flow to navigable waters

  • Non isolated lakes and ponds,

  • Adjacent wetlands that abut or have a direct surface hydrological connection to a TNW,

  • Ditches built within a tributary or a wetland, and

  • Impoundments of navigable waters.

The proposal specifically excludes certain waters including;

  • Ephemeral features

  • Most ditches

  • Artificially irrigated areasGroundwater

  • Prior converted cropland

  • Storm water control features

  • Waste treatment systems

  • Excavated pits and depressions incidental to mining or construction


While the new proposal goes a long way in clarifying federally regulated waters, landowners should not assume that the permit process will be any easier. In many cases, it may be hard to determine whether a water feature is a covered tributary of an excluded ditch or ephemeral pond, especially in the normally arid West. There will still be significant room for interpretation and Corps regulators may be reluctant to exclude certain aquatic features that have been historically regulated.