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EPA and USACE Issue New Clean Water Rule

Posted on Wed, Jul 1, 2015

The U.S. Environmental Protection Agency (EPA) and U.S. Army Corps of Engineers (USACE) on June 29, 2015 published a new Clean Water Rule that updates the definition of “Waters of the United States” regulated under the federal Clean Water Act (CWA). The CWA prohibits the unauthorized discharge of pollutants (including fill material) into “navigable waters”, which are defined as waters of the U.S.  Following adoption of the CWA in 1972, the EPA and USACE issued their own definitions of waters of the U.S., and the interpretation of these definitions has been subject to litigation in several Supreme Court cases, including most recently the “SWANCC” and “Rapanos” decisions in 2001 and 2006, respectively.

The following table provides a brief comparison of the existing definition of waters of the U.S. under the current rule with the new Clean Water Rule. A more detailed discussion is provided following the table.


  • The new Clean Water Rule keeps the first four categories of waters of the U.S. listed above the same as the current rule.  It also removes the fifth category that includes waters subject to jurisdiction based on a connection to interstate or foreign commerce. 
  • The rule provides new definitions and expansions for the sixth and seventh categories of the current rule.  Tributaries are defined as “characterized by the presence of the physical indicators of bed and banks and an ordinary high water mark.” The new rule also defines adjacent (“bordering, contiguous, or neighboring”) and expands the category of adjacent wetlands to all non-wetland waters within 100 feet of jurisdictional waters (categories 1 – 4, and 6, above), or within the 100-year floodplain to a maximum of 1,500 feet from the ordinary high water mark of these waters. 
  • Further, specific isolated waters, such as “western vernal pools”, are waters of the U.S. if they are determined to have a significant nexus with categories 1 through 3, above.  Other isolated waters are jurisdictional if they occur within the 100-year floodplain of categories 1 – 3 above, or within 4,000 feet of the ordinary high water mark of categories 1 – 4, and 6, and are determined to have a significant nexus with these waters.
  • The new rule also adds categories of exclusions under the current rule that meet specific criteria, including (but not limited to) certain types of ditches, artificially irrigated areas, erosional features, wastewater recycling structures, and puddles.

CleanWatersThe Clean Water Rule will go into effect on August 28, 2015, 60 days from publication in the Federal Register.  The new definitions in the rule are expected to reduce the level of case-specific determinations that occur under the current rule.  The USACE and EPA will likely issue additional guidance on implementing jurisdictional determinations under the new rule, as they did following the Rapanos decision in 2006.

Although the method of certain jurisdictional determinations may change, the Clean Water Rule is unlikely to substantially change the extent of USACE jurisdiction as it is determined under the current rule.  For example, in most situations features that would meet the criteria of the newly defined tributaries (i.e. containing physical indicators of bed and banks and an ordinary high water mark) would have likely been determined waters of the U.S. under the current rule through application of a significant nexus evaluation.  Further, the guidance that the USACE developed following the Rapanos decision in 2006 already excluded most types of ditches excavated in uplands and storm water facilities as waters of the U.S.  The new Clean Water Rule now defines that exclusion in the statute.

The new rule may expand USACE jurisdiction in the case of some features, such as non-wetland waters located adjacent to other jurisdictional features that previously didn’t have a significant nexus.  However, in California this may have positive implications for regulatory permit acquisition. USACE involvement can streamline the process of acquiring a water quality certification from the state Regional Water Quality Control Board (RWQCB).  When an applicant applies for a CWA Section 404 permit for the discharge of fill, the RWQCB must adhere to the USACE permitting timeframe for issuing a CWA Section 401 water quality certification.  If USACE jurisdiction is absent, the process of obtaining Water Board authorization for impacts to isolated waters of the state can be much longer.   

Rincon will continue to track the application of the Clean Water Rule and its implications for permitting projects. If you have questions, contact Steven J. Hongola, Senior Ecologist and Program Manager, at 805-644-4455. Click here for more information on Rincon’s wetland delineation and regulatory permitting services.

For more information on the new Clean Water Rule see the EPA’s website

Topics: United States Environmental Protection Agency, EPA, water, water quality