The CLEAN WATER RULE – Why “Navigability” Matters

History of the Clean Water Act

Cuyahoga River – then and now

In 1969 the Cuyahoga River in Ohio burst into flames.  Time magazine’s photos of the burning river noted that it was so saturated with sewage and industrial waste that it “oozes rather than flows.”  A record number of fish kills were also recorded in 1969.  These dramatic events led to widespread public outcries for greater protection of the Nation’s rivers and their water quality.  Congress recognized the need for action and passed the Clean Water Act of 1972 with strong bi-partisan support.

Cuyahoga River on fire and restored today

The objective of the Clean Water Act was, and remains, to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.”  The Clean Water Act is a critical part of the bedrock protection of human health and the environment and it is widely regarded as one of the United States’ greatest successes in environmental law.

Through the Clean Water Act, Congress gave EPA and the US Army Corps of Engineers (COE) authority to regulate “the Nation’s waters”,  also referred to as “navigable waters” within the Act.  These terms were not defined in the Act. 

The Definitional Conundrum: What “Waters” does the Clean Water Act Protect?

Does the Act provide federal pollution control protection only for major rivers (waters that are “navigable”)? Or does the Clean Water Act provide protection for  the rest of the hydrologic system (tributary streams, lakes, and wetlands) that are connected to “navigable waters”? 

From a practical standpoint, pollution that enters the system at any point will end up in “navigable waters.”  This was recognized in the 1972 Conference Report that accompanied the original legislation. This report said:

“navigable waters’ should be construed with “…the broadest possible constitutional interpretation…”.

The US Supreme Court has considered the issue of which “waters” are protected by the Clean Water Act several times – providing different interpretations over the years.  These court decisions have created considerable uncertainty for regulators and the regulated community alike.  One ruling found that waters with a “significant nexus” to “navigable waters” were subject to Clean Water Act protection.  A subsequent ruling included five separate opinions and three separate tests.  In a 2006 decision, Chief Justice Roberts called for the agencies to propose rules that would clarify which waters are subject to protection under the Clean Water Act.

In response, EPA and the COE finalized what is known as the “Clean Water Rule” to provide clarity and predictability about which waters are protected by the Clean Water Act.  This rule finalized in 2015 after exhaustive review of the scientific literary and extensive engagement with stakeholders across the country (400 meetings and more than one million comments). EPA published a synthesis of more than 1200 peer-reviewed scientific publications demonstrating that protection of small streams and wetlands is vital to in keeping larger downstream waters free of pollution.

The Clean Water rule was strongly supported by environmental groups, sportsmens’ organizations, public health officials and the scientific community.  Various development organizations and some States opposed the Rule and sued to block it.  (Scott Pruitt, then Oklahoma Attorney General and now EPA Administrator, was among those opposing the Rule).

Diagram showing interconnectivity of of streams, wetlands and lakes in watersheds.
Small upstream waters have great impact on larger waterbodies downstream.

The Clean Water Rule: A Definition Based on Hydrologic Science

At the heart of the Clean Water Rule is scientific understanding of the connections between headwater stream systems and downstream waters.  The hydrologic system can be envisioned as similar to our own blood system.  Small blood vessels (capillaries) are connected to larger veins and arteries, and anything happening within those small capillaries can have great impact on the larger system.   The Clean Water Rule protects tributary streams (like capillaries) that have impacts to downstream waters.

The Clean Water Rule protects streams that may be dry for some parts of the year.   The Rule provides a physical, measurable definition: a tributary must show physical features of flowing water – a bed, bank, and ordinary high water mark – to be protected under the Clean Water Act.

In the West, most of our rivers and streams are not “navigable” year around.  Western watersheds characteristically include many miles of waterways where water may be only seasonally or intermittently present.  The mileage of such streams greatly outnumbers the mileage of perennial streams throughout the semi-arid West .  Nevertheless, these waterways are hydrologically connected to downstream waters, and pollution flows downstream.  For example, mining wastes dumped in a seasonal headwaters stream will flow into “navigable waters.”  The West’s seasonal, intermittent streams are protected under the Clean Water Rule.

Stream showing low water and high water mark.
Typical Western stream in mid-summer. The high water mark is clearly visible.

The Clean Water Rule are  also offers clear definitions of which “adjacent waters” (i.e prairie potholes, western vernal pools, etc.) are covered when they impact waters downstream. 

By providing definitional clarity, the Rule reduces the need for case-specific evaluations – a time consuming process that creates uncertainty for everyone.

What the Clean Water Rule protects

What the Clean Water Rule Does Not Cover

There is considerable mis-information about what the Clean Water Rule does and does NOT protect.

  • The Clean Water Rule does not change regulate irrigation ditches or change existing agricultural exemptions.
  • The Clean Water Rule does not change existing permits for municipal stormwater and wastewater systems.
  • The Clean Water Rule does not regulate groundwater. 
  • The Clean Water Rule does not protect “puddles” (Scott Pruitt’s comments notwithstanding).

What the Clean Water Rule does NOT protect

The Trump Administration’s Rollback of the Clean Water Rule

In February 2017 President Trump issued an Executive Order requiring a “review” of the “Waters of the United States Rule” (i.e. the Clean Water Rule, or WOTUS).  In March 2017 notice was published in the Federal Register of the Adminstration’s “Intentions To Review and Rescind or Revise the Clean Water Rule.” 

The Trump Administration has signaled its intent to re-define Clean Water Act protections very narrowly, providing protections only to “navigable waters.” This definition would exclude thousands of miles of smaller streams and millions of acres of wetlands all across the U.S.

On July 27th, the Administration issued a proposal rescind the Clean Water Rule. https://www/ 

This action (open for public comment now) would return us to the legal uncertainty (and case-by-case determinations) that the Clean Water Rule was designed to clear up. 

Later this year, the Trump Administration plans to propose a new Rule with a different definition of which “waters” are protected by the Clean Water Act – likely limiting protection to “navigable waters” only.

Make Your Voice Heard

As Westerners, we all know the essential value of water.  Clean water is critical to our drinking water and public health.  It is also vital to our local economies, whether that economy is based on manufacturing, agriculture, brewing beer or recreational tourism.  Clean water is an essential component of our quality of lives.

If the Trump Administration succeeds in narrowing the definition of  “waters of the United States,” many critical waterways will no longer protected under the Clean Water Act.  Water supplies for millions of Americans will  be at risk.

It is vital that we speak out to defend our water quality protections.  You can comment on the Trump Administration’s proposal – it’s easy, and you don’t have to be an expert to be heard. We’ve prepared some suggested talking points, along with guidance on how to comment on our website Defending Our Waters

Comments must be received on or before September 27, 2017

In addition, you can write letters to the editor and share this information in your own social media networks. And you can let your Congressional representatives and Governors know that you want to  retain the full scope of Clean Water Act protections for our nations waters.

For Save EPA

   Gene Reetz Ph.D. (retired Senior Water Resources Scientist)

   Join Teter (retired  Enforcement Attorney)

   Wes Wilson (retired Environmental Engineer)

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Save EPA has been an all-volunteer group of former EPA officials who became alarmed about the Trump agenda for EPA and joined together to fight it.

With newly-elected President-Elect Biden and VP-Elect Harris coming in January, the need to "save EPA" is much less urgent. This is not to imply all clear skies ahead - there is much re-building to do, there will be negative pressures on the new administration, and we will likely have policy differences in the future. However, we are hopeful that these differences will be discussed rationally, using science as a basis for moving forward, and keeping EPA's mission of protecting human health and the environment in the forefront.

And so, we are going back to retirement!  We're keeping our website up at , as a resource for those who want to follow and influence the restoration work. Our report on the Trump record at EPA describes the actions that need to be reversed [], and our guide to participating in the rulemaking process [] can help you be part of the solution.

Thank you for your support and commitment during the past 3.5 years.  While the Trump assaults were unending, they were also frequently unsuccessful, and that was due in large part to public outrage.  Keep it up!  Although EPA will be in much better hands with a Biden administration, there is always a need for an informed and engaged public.

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