On Monday, a federal district court judge in Arizona threw out the definition of “waters of the United States” that the Trump administration promulgated in 2020. The 2020 rule severely limited the reach of the Clean Water Act (CWA) in protecting invaluable bodies of water and left large numbers of wetlands and streams unprotected from polluters and open to destruction from dredging and filling.
The definition of “waters of the United States,” commonly referred to as WOTUS, identifies the waters covered by the Clean Water Act (CWA). If a stream or wetland is not classified as a body of water belonging to the United States, it’s not protected by the act.
The Arizona court found that the 2020 WOTUS rule resulted in the almost total elimination of CWA coverage for streams in Arizona and New Mexico, which the court held was “a significant shift from the status of streams under both the [Obama 2015 rule] and the pre-2015 regulatory regime.”
The damage caused by the Trump-era WOTUS rule was not limited to just those two states. The 2020 rule eliminated CWA protections for all ephemeral streams (waters that flow during or for a short time after rainfall), some intermittent streams and many wetlands, among others. A 2008 report by the Environmental Protection Agency (EPA) documented that 59 percent of all the streams in the U.S. (with the exclusion of Alaska) and 81 percent of streams in the arid southwestern states are intermittent or ephemeral. The report further documented that these intermittent and ephemeral streams are critical to downstream water quality and to the health and welfare of the American people, especially in communities disproportionately affected by pollution.
Over 117 million people, a third of the U.S. population, drink water that relies, at least in part, on these intermittent and ephemeral streams. The protection of these streams and their associated wetlands is also critical to reducing pollution from urban discharges, trapping sediments, mitigating floods and providing habitat for wildlife.
The regulatory question of what waters are covered by the CWA has ping-ponged for 20 years. From the passage of the CWA in 1972 to 2001, most waters and wetlands in the United States were protected to meet the law’s objective to “restore and maintain the chemical, physical, and biological integrity of the nation’s waters.”
But in 2001, in a case known as SWANCC, the Supreme Court required a showing of a “significant nexus” between a stream or wetland and downstream navigable water for the CWA to apply. That decision and the follow-up 2006 opinion in Rapanos v. United States sewed much confusion over what constituted a “significant” connection.
Further muddying the waters, the Bush administration issued confusing guidance in 2008 that recommended complicated and time-consuming analyses in determining CWA coverage. Then, in 2015, relying on stream and wetland science, the Obama administration promulgated a new rule that defined all intermittent and ephemeral streams and their adjacent wetlands as waters of the U.S. That rule was heavily challenged by the industry and agriculture lobbies as well as Republican state governments and did not go into effect in many states. (One of the authors here — Mark Ryan — worked on the 2015 WOTUS rule while at EPA.)
In a serious setback, the Trump administration repealed the 2015 rule and promulgated a much-weakened rule that dramatically reduced CWA protections nationwide. Most notably, the Trump rule removed all protections for ephemeral streams as well as many intermittent streams and wetlands.
In this week’s latest head-turning action, the Arizona Court vacated the previous administration’s rule in part because it ignored the large body of science that EPA had assembled showing that protecting intermittent and ephemeral streams and their adjacent wetlands was critical to the health of downstream waters. The Biden administration has already announced its intention to repeal the 2020 rule and replace it with a more protective rule while also addressing issues raised by opponents to the 2015 rule.
If Monday’s court ruling withstands the inevitable appeal, it will allow EPA to avoid the cumbersome rulemaking process needed to repeal the 2020 rule and begin to immediately develop a new WOTUS definition based on well-established science that meets CWA objectives. While this is a job that should be done by Congress, partisan politics have continued to stand in the way. Consequently, EPA and the U.S. Army Corps of Engineers, its partner in wetlands protection are forced to fill that vacuum.
In drafting the replacement rule, EPA should promulgate a definition of WOTUS that covers all streams and wetlands that impact the health of downstream waters. It could effectively do so by designating physical characteristics of those streams and wetlands on a regional ecological basis rather than taking a nationwide, one-size-fits-all approach. The filling, for example, of a small wetland in Idaho, which has few wetlands, would have a major impact compared to filling a wetland in a wetland-rich state like Florida. EPA has been surveying coastal waters, lakes, rivers and streams and wetlands since 2007, and has the data needed to support a regionalized definition of WOTUS.
Flowing water doesn’t respect state boundaries. That’s why EPA should also make it clear that all interstate waters are covered by the CWA to ensure consistency and collaboration across the many waters that define or cross state boundaries. EPA should also reinstate CWA coverage for wetlands that connect to adjacent waters through groundwater since those wetlands are significant contributors to downstream water quality.
The WOTUS rule has been in litigation now for over 20 years and was seriously weakened by the Trump rule. EPA now can finally put forth a rule that gets it right. We deserve nothing less to protect our right to clean water.
Mark Ryan served as an assistant regional counsel for EPA Region 10 and special assistant U.S. attorney at the Department of Justice. Ryan was an author of the 2015 Clean Water Rule. Betsy Southerland is the former director of Science & Technology in the EPA Office of Water.