The Murkiness of the Clean Water Act

Since its passage in 1972, the Clean Water Act’s exact jurisdiction has been unclear. Read this overview and learn how recent developments affect landscape architects working on water and stormwater management projects across the nation.


Since its passage in 1972, the Clean Water Act’s exact jurisdiction has been unclear. The description included in the original law states that the Clean Water Act is applicable to navigable waters, which it defined as “waters of the United States” commonly referred to as WOTUS. To fix the vagueness, the Environmental Protection Agency (EPA) published a clarification in the Federal Register in 1988. The EPA defined WOTUS as all waters that are, may be, or used in interstate or foreign commerce and/or are subject to tidal flow. It also includes all interstate wetlands, lakes, rivers, streams, mudflats, sand flats, ponds, etc. that could through use or degradation or destruction affect interstate or foreign commerce. Lastly, the EPA included all tributaries to the aforementioned as WOTUS as well.

During the last 18 years, lawsuits against the EPA and the federal government created a patchwork of definitions across the United States. Finally, the case reached the U.S. Supreme Court, which issued a ruling in 2006. The court defined WOTUS as follows:

“only those relatively permanent, standing or continuously flowing bodies of water ‘forming geographic features’ that are described in ordinary parlance as ‘streams,’ ‘oceans, rivers, [and] lakes’” and that is does not include “channels through which water flows intermittently or ephemerally, or channels that periodically provide drainage for rainfall.”

However, the court’s 4-1-4 decision with no clear majority and little instruction on how lower courts should proceed. Therefore, since 2006 different courts have taken a multitude of actions creating a patchwork of definitions and interpretations of what exactly WOTUS meant.

In an attempt to end the confusion, the Obama administration published the Clean Water Rule in the Federal Register in 2015. The Clean Water Rule attempted to strike a balance between the 1988 EPA and 2006 Supreme Court definitions by declaring that tributaries that have physical signs of flowing water, even if they do not run year-round and ditches that “look and act” like tributaries are included. The rules also limited Clean Water Act enforcement to bodies of water within 1,500 feet of another body of water already covered barring a surface connection. Additionally, the EPA kept longstanding exemptions for agricultural waters such as tile drainage systems and the moving of livestock.

Immediately after the Obama administration published this rule, some congressional leaders decried it as a power-grab. They passed a resolution in the U.S. House of Representatives attempting to overturn the rule and sued the administration in multiple courts. Due to the slow rollout of federal rules, the injunctions from courts delaying implementation, and the change in administration, the rule never fully went into effect. In February 2017, President Trump halted the rule through executive order, instructing the EPA and the Army Corps of Engineers to review the rule and determine how to either revise or rescind it.

In August of 2018, a federal judge in South Carolina found that the Trump administration had violated federal law when suspending the rule by not following the proper procedure for rescinding a proposed rule. Due to this ruling, the Obama administration’s definition (as of this publication) applies to the states of California, Delaware, Hawaii, Illinois, Iowa, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, New Hampshire, New Jersey, New York, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, Tennessee, Texas, Vermont, Virginia, and Washington. Due to injunctions from other judges, however, this rule’s definition remains suspended in the 24 other states. It is currently unclear when or even if there will be a clear and nationally implemented definition of WOTUS.

The WOTUS Rule and the recent court ruling affects landscape architects working on water and stormwater management projects across the nation. Many landscape architects have expressed a need for consistency and predictability regarding federal water protection rules. What permits and procedures apply, and what natural environments the Clean Water Act covers can completely change an approach to a design. Changing the rules mid-project could halt or event indefinitely stop a plan. ASLA government affairs has been monitoring this rule closely and working with allies and partners on the best steps forward in promoting a clear and consistent definition of Waters of the U.S.



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