The Supreme Court’s decision in Sackett v. EPA, implemented by the Environmental Protection Agency (EPA) in an Aug. 29 rule, upended federal regulation of the nation’s water resources at a dire hydrological time for the western United States. Accelerating climate change, two centuries of unbridled consumption and development, and a ballooning urban population have depleted water supplies in a region with a long history of conflict over natural resources and their governance. The deregulatory cascade unleashed by Sackett may only worsen this crisis, reigniting simmering tensions over water rights between states, industries, cities, and a host of other regional stakeholders.

Sackett v. EPA and the Federal Government’s Powers Under the Clean Water Act

In Sackett, the Court circumscribed the reach of the Clean Water Act (CWA) of 1972 by narrowing the criteria by which certain wetlands and waterways may qualify as “waters of the United States” (WOTUS), which the CWA protects. In tow, bound by the Court’s decision, the EPA stripped federal protections from, according to some estimates, nearly 60 million acres of wetlands and streams. (That acreage amounts to upwards of half of the United States’ remaining wetlands; more than 50 percent of the country’s original wetlands have been destroyed since European settlement.)

Sackett began with an Idaho couple. After the Sacketts filled in a wetland on their property in 2007 to build a house, the EPA contended that the wetland was protected by the CWA because of its placement between a neighboring marsh and a lake. The agency ordered the couple to restore the degraded wetland. The couple then sued the EPA, arguing that their wetland should not qualify as WOTUS because it does not connect superficially to the nearby waterbodies. The legal battle wound its way through the court system for nearly 15 years before the Supreme Court’s ruling in May.

The Sacketts’ lawsuit joined an array of past cases that interrogated the federal government’s statutory right to regulate the nation’s waterbodies. Principal among them is a 2006 Supreme Court case, Rapanos v. United States. In Rapanos, Justice Anthony Kennedy argued in a concurring opinion that waterways and wetlands with a “significant nexus” to an interstate waterway qualify as WOTUS, meaning they deserve protections under the CWA. Functionally, a “significant nexus” denotes some degree of hydrological connection between a waterway or wetland and WOTUS, even if that connection lies underground or otherwise out of sight.

Four of the justices disagreed. Then-Justice Antonin Scalia, joined by Justices John Roberts, Samuel Alito, and Clarence Thomas, put forward the argument that eventually prevailed in Sackett: Namely, that wetlands and waterbodies that have no surface connection to navigable, CWA-protected waterbodies are not WOTUS and thus do not qualify for CWA protections. The justices asserted that the CWA should not extend to “channels through which water flows intermittently or ephemerally, or channels that periodically provide drainage for rainfall.” Rather, it should only cover wetlands and waterways with a “continuous surface connection” to interstate waterbodies.

The Court’s failure to issue a majority opinion in Rapanos compounded decades of regulatory uncertainty around the CWA and federal oversight of the nation’s waterbodies. Much of that uncertainty arose from the CWA’s lack of a textual definition for WOTUS. The EPA is responsible for defining the term, and federal courts must weigh whether the EPA definition falls within the federal government’s regulatory purview as authorized by the CWA. Recent presidential administrations issued WOTUS-defining rules often shaped by familiar ideological approaches to environmental and conservation issues. With no judicial consensus in Rapanos, the case was remanded to lower courts. In the years between 2006 and the Sackett ruling, federal judges chose between the wider and narrower definitions of the CWA’s reach when hearing cases relating to the federal government’s jurisdiction over U.S. water resources.

With Sackett, the Scalia camp won out 17 years later. Justices Amy Coney Barrett, Alito, Thomas, Roberts, and Neil Gorsuch imposed that narrower criterion on the nation’s waterways and wetlands, ruling that such waterbodies must have a “continuous surface connection” with WOTUS to fall under the aegis of the CWA. Justices Brett Kavanaugh, Ketanji Brown Jackson, Sonia Sotomayor, and Elena Kagan concurred with the majority as concerned the Sacketts’ property but, pertaining to the question of the CWA’s scope, wrote in favor of Kennedy’s approach in the Rapanos case. Handcuffed by the Court, the EPA’s subsequent rule removed tens of millions of acres of wetlands and waterways from the CWA’s scope.

Sackett’s Potential Far-Reaching Effects on Water Resources in the West

The Sackett decision and the attendant EPA rule come amid persistent – and mounting – water challenges in the American west. Climate change is desiccating the region. Historical records indicate that the west is already in the midst of the worst drought in 1,200 years. Beyond the climatological factors, rapid urbanization and agricultural expansion have depleted the region’s groundwater. The region’s cities rank among the fastest growing in the country even as the water to support such breakneck development dries up.

Adding to those woes, the types of waterways and wetlands stripped of protections by Sackett abound in the west. The eastern United States’ climate and hydrology generally keep waterbodies wet or frozen year-round. Wet, humid summers allow most eastern waterways and wetlands to maintain that critical “continuous surface connection” to WOTUS, keeping them within the federal government’s purview. The west, meanwhile, is naturally arid, with little rainfall coming in the summer months. Many of the region’s waterways are thus “ephemeral,” only running water (in the case of streams) or wet (in the case of wetlands) from the fall through the spring. These types of waterways constitute about 60 percent of the nation’s streams. In the southwest, they are more than 80 percent of all streams.

These ephemeral streams and wetlands are a critical resource in the region. Streams or wetlands might seem like minor, hydrologically unimportant water sources compared to rivers or reservoirs. But more than one-third of the U.S. population – 117 million Americans – at least partially relies on more than 200,000 miles of these streams for potable water. Nearly all of some western states’ streams are ephemeral. In Arizona alone, more than 3.2 million people count on them to replenish public drinking water systems; 94 percent of the state’s streams run only part of the time. Just under 90 percent of Nevada’s and New Mexico’s streams are ephemeral, as are around 80 percent of Utah’s and nearly 75 percent of California’s and Colorado’s.

The Court’s finding that wetlands and ephemeral streams do not qualify as WOTUS also ignored hydrological reality. The Court focused on a “continuous surface connection” as the deciding factor in evaluating any given waterway’s or wetland’s relationship to WOTUS. But the wetlands and waterways targeted by the Court’s decision are very much connected to those waters covered by the CWA, despite the lack of a superficial link. As the Kennedy camp originally noted in the Rapanos decision, waterways interconnect via a network of underground channels and other subterranean mechanisms. The effects of pollution or depletion of a wetland or ephemeral stream, now beyond the reach of federal law, do not remain within that one waterway; they will affect major waterbodies still covered by the CWA, risking the draining or contamination of drinking water for millions of Americans and the destruction of wetland and riparian ecosystems.

Now, developers, industries, and landowners need not obtain a CWA permit to pollute or deplete these types of wetlands and waterways. Local and state regulations are their only remaining safeguard. And those regulations vary in strength, with some states previously completely dependent on the federal government to protect local waterbodies. The dissolution of the CWA’s regulatory schematic for these waters could well spark the recrudescence of bitter fights over the rights to an ever-shrinking resource.

The Fight to Come in a Region with a Long History of Land-Use Conflict

Sackett may further inflame long-running tensions in the west over natural resources and their governance. The decision not only opens up millions of acres to development and the depredations of industry. It also removes a key legal and financial disincentive that has deterred polluters from fouling the west’s waterways via dumping and wastewater disposal. With those federal protections now slashed, and with prolonged, punishing drought a near certainty in the region, dormant antagonisms over water rights may erupt.

States, tribes, industries, and the federal government have fought a centuries-long, pitched battle over the west’s natural resources. Even more precious because of its comparative scarcity, water – and control of it – has inspired fierce and sometimes violent struggles between various actors jockeying for rights. Arizona and California fought riverine naval skirmishes for Colorado River apportionments. The “water wars” of the west are infamous enough to have been immortalized in American cinema: see “Chinatown.”

A change in the federal government’s approach to the west’s lands and waters helped ameliorate those conflicts. The environmental zeitgeist of the 1970s led the U.S. government to prioritize preservation in its approach to the region’s natural resources. Laws like the CWA and the Endangered Species Act, despite inconsistency in their reach and enforcement, introduced a new degree of predictability into water-rights deliberations and reversed preceding eras of plunder. The CWA spared regional water resources from pollution and depletion. And while federal regulations have embittered local stakeholders and fueled vicious political and legal fights, they have also provided a stable regulatory hand.

Now, in the wake of Sackett, states are left to play arbiter. And their poor record of water stewardship is cause for concern. Utah, Colorado, Nevada, New Mexico, and Texas fully rely on the regulatory framework of the CWA to protect their water resources, including wetlands and ephemeral streams; those resources are now defenseless. The state codes of California and Arizona criminalize pollution of some wetlands and streams, but the extent of the coverage and severity of the penalties vary. State planners have overestimated water volumes in the critical Colorado River and tend to punish polluters less harshly than the federal government. Labyrinthian state laws and water-sharing compacts have not been updated, in some cases, in over a century. One need only look to the slow demise of the Great Salt Lake, a victim of climate change but also of Utah’s failure to prevent cities and industries from draining the waterbody to near death, to see states’ uneven record of preserving vital water resources.

Sackett creates a regulatory vacuum in which industry may further stake its claim to the region’s unprotected wetlands and ephemeral streams. Petroleum industry groups filed an amicus brief in support of the Sacketts. Oil and gas production is both a significant user and polluter of fresh water across the United States. Mining companies are also frequent despoilers of western water resources and now face one less regulatory hurdle to consume and pollute. The real estate development industry also applauded the Sackett ruling, which will allow developers to fill in previously off-limits wetlands in the absence of strict state laws against such practices.

Federal and state lawmakers could restore protections where Sackett eliminated them, but polarization may hinder progress. Sackett all but precludes future executive-branch remedies. Congress could update the CWA to define WOTUS, which the current law does not, based on the “significant nexus” test advocated by Justice Kennedy in Rapanos. In the absence of federal policy, state legislators could impose wetland and ephemeral stream protections within their own borders as, for example, California did in 2019. But given divided control of Congress, modern political acrimony around natural resources and conservation, and the partisan balance of power in statehouses across the west, adequate legislative fixes to the regulatory hole left by Sackett are likely to prove elusive.

The potential costs of inaction are high. Several cities in the region routinely feature on lists of population centers likely to face water shortages by midcentury. Thanks to a shifting climate and rapid urbanization, water resources are already stretched thin in the west. Growing cities depend on reliable, unpolluted water. Anti-government groups have also made water and control of it a flashpoint in the past. As agriculture, industry, and tribes, among other actors, maneuver for access, the lack of regulatory heft offered by the CWA and the federal government may give rise to a free-for-all with grave consequences.


Key to the decline of the resource-based conflict typical of the nineteenth and early twentieth centuries was the imposition of federal government regulation of public lands and waters. The Sackett decision removed the federal government as the primary sentinel of hundreds of thousands of miles of ephemeral streams and millions of acres of wetlands in the American west. The region’s water situation, already tenuous, is not improving. Projections are nearly unanimous in asserting that water will grow all the scarcer in the west as the twenty-first century progresses. As states, industries, farms, urban centers, and other interests wrestle for an essential, diminishing resource and attempt to navigate an arcane water-rights regime, water insecurity and conflict may spike in Sackett’s deregulatory wake.

The author would like to thank Zoe Wynn, Lona Girardin, and Jack Silvers for their research and fact-checking support.

IMAGE: The Colorado River at White Canyon is viewed from 37,000 feet taken from a United Airlines A319 on September 1, 2023, near White Canyon, Utah. (Photo by George Rose/Getty Images)