What’s up with WOTUS?

The tides and grasses of a salt marsh, the black water and buttressed trunks of a cypress swamp, and the scrubby forest of a Carolina Bay can all be described under the umbrella term of “wetland.” However, the varied characteristics of wetlands in coastal South Carolina can create confusion about how they fit into regulatory definitions and jurisdictional determinations. According to the EPA, the Clean Water Act established federal jurisdiction over “navigable waters,” defined in the Act as the “waters of the United States” or WOTUS. The Clean Water Act provides discretion for the EPA and U.S. Department of the Army to define “waters of the United States” in regulations. 

In the summer of 2020, the North Inlet – Winyah Bay and ACE Basin NERRS partnered to host a wetland regulation training program. These recorded webinars brought experts from federal and state regulatory agencies to provide up-to-date information and guidance to planners, land use professionals, and other coastal decision-makers. However, regulatory rules and definitions are often changed and revised over time. In this case, the WOTUS definition that applied during the 2020 wetland trainings was recently changed.

Since changes to WOTUS have important consequences for land use, wetland protection, water quality, and more, we wanted to provide an update. We checked in with Richard Darden, USACE, one of our speakers from the wetland regulation webinars, and asked him to share the facts on the WOTUS definition update. For those who attended previous wetland trainings or those interested in learning more about wetlands, the responses compiled below provide clarification on the current WOTUS definition and what this change means for wetlands in coastal SC.



  • What is the timeline of recent changes to the WOTUS definition?

What happened: Consistent with the U.S. District Court for the District of Arizona’s August 30, 2021, order vacating and remanding the Navigable Waters Protection Rule, the agencies have halted implementation of the Navigable Waters Protection Rule and are interpreting “waters of the United States” consistent with the pre-2015 regulatory regime until further notice. The table below summarizes the timeline from 1986 to present.

33 CFR 328.3: Definition of Waters of the United States

Year Implemented

Referred To As

Applied to SC?



’86 Regs


Included 2001 SWANCC and 2007-08 Rapanos Guidance


Clean Water Rule (aka Obama Rule)


’86 Regs continued in 22 states, including SC


Navigable Waters Protection Rule




’86 Regs (again)

[Also called “pre-2015 WOTUS regime”]


Currently applicable nationwide

 Note that the current administration announced a rulemaking which is on-going.

  • Who are the key players (agencies, organizations, etc.) involved in these changes?

EPA and the US Army Corps of Engineers (USACE) are the two federal agencies that have authority to determine jurisdiction regarding Waters of the U.S.  Note that no reference is made to any states that have their own “state-level” regulations regarding wetlands and other waters.

Note also the USDA follows the Food Security Act to identify and delineate wetlands on participating agriculture properties, including designating Prior Converted Croplands…but does not determine federal jurisdiction as part of this service.

The South Carolina Department of Health and Environmental Control (SCDHEC) will follow the lead of the federal govt with respect to how it impacts its role through the Federal Consistency process and Bureau of Water’s water quality program.

  • What are now considered Waters of the United States?

Waters of the U.S. are determined following the 1986 regulations at 33 CFR 328.3, including with implementation of SWANCC and Rapanos Guidance based on those Supreme Court decisions/opinions.

33 CFR 328.3 Definitions.

For the purpose of this regulation these terms are defined as follows:

(a) The term waters of the United States means

(1) All waters which are currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide;

(2) All interstate waters including interstate wetlands;

(3) All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sandflats, wetlands, sloughs, prairie potholes, wet meadows, playa lakes, or natural ponds, the use, degradation or destruction of which could affect interstate or foreign commerce including any such waters:

(i) Which are or could be used by interstate or foreign travelers for recreational or other purposes; or

(ii) From which fish or shellfish are or could be taken and sold in interstate or foreign commerce; or

(iii) Which are used or could be used for industrial purpose by industries in interstate commerce;

(4) All impoundments of waters otherwise defined as waters of the United States under the definition;

(5) Tributaries of waters identified in paragraphs (a) (1) through (4) of this section;

(6) The territorial seas;

(7) Wetlands adjacent to waters (other than waters that are themselves

wetlands) identified in paragraphs (a) (1) through (6) of this section.

  • What are the implications of this change?

It re-establishes the broader definition of adjacency for wetlands and broader coverage for linear waters that were substantially reduced under the Navigable Waters Protection Rule

  • When does this change take effect?

September 3, 2021

  • Who is most impacted by this change?

Permit applicants and those that may not have needed permits under the NWPR definition of Water of the U.S.  Note also that all U.S. citizens are at least indirectly affected by regulations that provide greater or lesser protection for aquatic resources.

  • What is the impact on permitting processes?

There is no change in the permitting process; however, the number and extent of permit applications may be affected by somewhat broader jurisdiction.

  • Where can I go to find out more information?