The Sackett Problem

In May 2023, the Supreme Court of the United States issued its decision in Sackett v. Environmental Protection Agency, a case about whether a couple in Idaho needed a federal permit to build a house on their residential lot near Priest Lake.¹ The case began as a property rights dispute. It ended as a restructuring of the Clean Water Act that eliminated federal protection for an estimated 51 to 63 million acres of wetlands across the United States.²

The decision was unanimous on the narrow question: the Sacketts’ property was not subject to Clean Water Act jurisdiction. But the reasoning was divided 5 to 4, and it is the reasoning, not the result, that constitutes the problem. Justice Alito, writing for the majority, adopted a test that requires wetlands to have a “continuous surface connection” to navigable waters in order to qualify for federal protection.³ Wetlands that are separated from navigable waters by a berm, a road, a dry stretch of ground, or any interruption in the surface flow, no matter how hydrologically connected they are underground, no longer fall within the Act’s jurisdiction.

Justice Kavanaugh, concurring in the judgment but dissenting from the majority’s reasoning, wrote that the continuous surface connection test “departs from the statutory text, from 45 years of consistent agency practice, and from this Court’s precedent.”⁴ He was joined by Justices Sotomayor, Kagan, and Jackson. The concurrence is unusual in its directness: a conservative justice, appointed by the same president who appointed Justice Alito, telling the majority it got the law wrong.

The effects of the decision are not speculative. They are measurable, ongoing, and in many regions of the country, irreversible.

What wetlands do

Before examining what Sackett removed, it is worth understanding what wetlands provide. The term “wetland” covers an ecologically diverse set of landscapes: marshes, swamps, bogs, fens, prairie potholes, vernal pools, playa lakes, and riparian floodplains. What they share is the presence of water at or near the surface for sufficient periods to support vegetation adapted to saturated soil conditions.⁵

The ecological functions of wetlands are well documented and not seriously disputed by any party to the Sackett litigation.

Wetlands filter water. As water moves through wetland soils and vegetation, sediments settle, nutrients are absorbed, and pollutants including heavy metals and excess nitrogen are broken down or sequestered. A single acre of wetland can filter approximately 7.3 million gallons of water per year.⁶ The water quality benefits of wetlands are so significant that some municipalities have invested in constructed wetlands as a cost-effective alternative to conventional water treatment infrastructure.

Wetlands prevent flooding. They function as natural sponges, absorbing excess water during storms and releasing it slowly over time. This buffering capacity reduces the volume and velocity of runoff that reaches rivers, lakes, and downstream communities. The National Wildlife Federation has estimated that wetland loss in the United States contributes to approximately $7.7 billion in annual flood damage, a figure that grows as remaining wetlands are degraded or destroyed and as climate change intensifies precipitation events.⁷

Wetlands store carbon. Peatlands, a category of wetlands, contain approximately twice as much carbon as all the world’s forests combined, despite covering only about 3 percent of the Earth’s land surface.⁸ When wetlands are drained or filled, the stored carbon oxidizes and enters the atmosphere as carbon dioxide. Wetland destruction is therefore both an ecological loss and a climate liability.

Wetlands support biodiversity. More than one-third of all threatened and endangered species in the United States rely on wetlands for some part of their life cycle.⁹ Migratory birds depend on wetland chains (often separated by substantial distances) as stopover habitat during continental migrations. Amphibians, many of which require both aquatic and terrestrial habitats, are disproportionately dependent on small, isolated wetlands of the kind the Sackett decision stripped of federal protection.

These are not aesthetic values. They are economic, ecological, and public health functions. Wetlands reduce the cost of water treatment. They reduce the cost of flood recovery. They reduce the rate of carbon emissions. They sustain fisheries, support agriculture through groundwater recharge, and maintain the biological diversity on which ecosystem stability depends. The EPA has estimated that the ecosystem services provided by wetlands in the United States are worth tens of billions of dollars annually.¹⁰

What the law was

The Clean Water Act, passed in 1972 over President Nixon’s veto, declared the objective of restoring and maintaining “the chemical, physical, and biological integrity of the Nation’s waters.”¹¹ Section 404 of the Act established a permitting program for the discharge of dredged or fill material into “waters of the United States,” a phrase that became the central contested term in four decades of litigation.

The Army Corps of Engineers, which administers the Section 404 program, and the EPA, which has oversight and enforcement authority, interpreted “waters of the United States” broadly. The interpretation included traditional navigable waters (rivers and lakes used in interstate commerce), their tributaries, and “adjacent” wetlands, meaning wetlands that are near, bordering, or contiguous with covered waters. Under this interpretation, a wetland did not need to be physically touching a navigable river to qualify for federal protection. It needed to be adjacent in a functional sense: connected through groundwater, periodic flooding, ecological relationships, or other hydrological links.

This broad interpretation was challenged repeatedly. In 2001, the Supreme Court in Solid Waste Agency of Northern Cook County v. U.S. Army Corps of Engineers (SWANCC) held that the Corps could not assert jurisdiction over isolated ponds based solely on their use by migratory birds.¹² The decision narrowed federal jurisdiction but did not resolve the question of which wetlands were covered.

In 2006, the Court addressed the question again in Rapanos v. United States, but failed to produce a majority opinion.¹³ Justice Scalia, writing for a four-justice plurality, argued that “waters of the United States” should be limited to relatively permanent, standing, or flowing bodies of water and wetlands with a continuous surface connection to such waters. Justice Kennedy, concurring only in the judgment, proposed a different test: wetlands are covered if they have a “significant nexus” to navigable waters, meaning they significantly affect the chemical, physical, or biological integrity of those waters.

Because no single opinion commanded a majority, lower courts were left to determine which test controlled. Most circuits adopted Kennedy’s “significant nexus” test, either as the sole standard or as an alternative to Scalia’s test. Under the significant nexus approach, a wetland could be federally protected if there was evidence, even if the connection was through groundwater or intermittent flooding, that it meaningfully affected the health of a downstream navigable water.

For 17 years, from 2006 to 2023, the significant nexus test was the dominant framework. It was not perfect. It required case-by-case analysis. It generated regulatory uncertainty. But it was rooted in the scientific reality that water does not respect surface boundaries, that a wetland separated from a river by a gravel road may be as hydrologically connected to that river as a wetland sitting on its bank.

What Sackett changed

The Sackett majority rejected the significant nexus test entirely. In its place, the Court adopted a version of Justice Scalia’s Rapanos plurality test, holding that the Clean Water Act covers only wetlands that are “indistinguishable” from waters of the United States, meaning they have a continuous surface connection to a navigable water such that it is difficult to determine where the water ends and the wetland begins.³

The test is, in practical terms, a visual one. If you can see water connecting the wetland to the river, the wetland is covered. If you cannot see the connection, even if the connection exists underground, the wetland is not covered. Groundwater connections, intermittent flooding, ecological relationships, and subsurface hydrology are, under this test, irrelevant.

The consequences are not abstract. The EPA estimated that the decision removed federal protection from between 51 and 63 million acres of wetlands, representing roughly half of the wetlands remaining in the contiguous United States.² The affected wetlands include:

Prairie potholes in the northern Great Plains, small depressions left by glacial retreat that fill with snowmelt and rain. These wetlands are separated from navigable waters by upland terrain but are critical habitat for waterfowl; they produce 50 to 80 percent of the continent’s ducks.¹⁴ Under Sackett, they lack a continuous surface connection and are no longer federally protected.

Vernal pools in California and the Northeast, seasonal wetlands that fill with winter and spring rains and dry by summer. They support species found nowhere else, including fairy shrimp, salamanders, and specialized plants. They are, by nature, disconnected from permanent surface waters. Under Sackett, they are unprotected.

Carolina bays, elliptical depressions scattered across the coastal plain of the southeastern United States. These wetlands are geographically isolated but ecologically significant, providing habitat for rare species and contributing to groundwater recharge. Under Sackett, their isolation from surface water removes them from federal jurisdiction.

Playa lakes in the southern Great Plains, shallow, circular wetlands that collect rainfall and runoff in an otherwise arid landscape. They are the primary recharge mechanism for the Ogallala Aquifer, the water source for one of the most productive agricultural regions in the world.¹⁵ Under Sackett, their lack of surface connection to navigable waters places them beyond the reach of the Clean Water Act.

In each case, the hydrological science is clear: these wetlands are connected to the broader water system through subsurface flows, seasonal inundation, and ecological processes. The Sackett test does not dispute this science. It simply declares it irrelevant to the legal analysis.

The state protection gap

The Sackett decision did not prohibit states from protecting the wetlands that lost federal coverage. It simply shifted the responsibility to state legislatures and agencies. Proponents of the decision, including some environmental federalism scholars, argued that this shift might produce stronger, more tailored protections: states with significant wetland resources would enact robust protections, while states without such resources would not bear unnecessary regulatory burdens.

The evidence to date does not support this prediction.

At the time of the Sackett decision, at least 10 states had no independent wetland protection laws.¹⁶ These states relied entirely on federal Clean Water Act jurisdiction to regulate the filling, draining, and destruction of wetlands within their borders. When Sackett removed federal protection from isolated and non-adjacent wetlands, these states had no backup regulatory framework.

Even in states with existing wetland protection programs, the coverage varies enormously. Some states, such as Massachusetts, New York, and Minnesota, have comprehensive wetland regulatory programs that approach or exceed the scope of pre-Sackett federal protection.¹⁷ Others have programs that cover only certain categories of wetlands, or that apply only in certain geographic areas, or that lack the enforcement mechanisms needed to deter violations.

The result is a patchwork. A wetland in Massachusetts may be protected by both state and federal law. An identical wetland in a state without independent protections is now subject to no regulation at all. The ecological functions of the wetland are the same. The flood prevention benefits are the same. The water filtration capacity is the same. The regulatory treatment depends entirely on which side of a state line the wetland happens to occupy.

This patchwork is not a temporary condition. Since the Sackett decision, relatively few states have enacted new wetland protection legislation. The political dynamics that prevented these states from enacting protections before Sackett have not changed. In several states, legislative proposals to fill the post-Sackett gap have been blocked by agricultural interests, real estate developers, and property rights organizations that view wetland regulation as an impediment to land use.

The consequence is a slow-motion loss. Wetlands that are no longer protected are not necessarily destroyed immediately. But they are exposed to filling, draining, and development without the permitting requirements that previously imposed at least some constraint. The Army Corps of Engineers, which processed approximately 60,000 Section 404 permit applications per year before Sackett, has seen its workload decline as activities that previously required permits no longer do.¹⁸ Each permit that is no longer required represents a wetland that can be altered or destroyed without federal review.

The flood cost

The relationship between wetland loss and flood damage is well established. Wetlands absorb and slow the movement of water. When they are removed from the landscape, more water moves faster into streams, rivers, and developed areas.

The $7.7 billion annual figure cited by the National Wildlife Federation is based on studies of the relationship between wetland coverage and flood insurance claims.⁷ The methodology is straightforward: areas with greater wetland loss experience higher flood damage, after controlling for development patterns, topography, and precipitation. The relationship is not linear (a 10 percent reduction in wetland coverage does not produce a 10 percent increase in flood damage), but it is consistent and statistically significant.

The cost is borne unevenly. Rural and low-income communities are disproportionately affected by the loss of wetland flood buffering, because they are less likely to have engineered flood control infrastructure and more likely to be located in areas where natural drainage systems, including wetlands, are the primary mechanism of flood mitigation. When a wetland upstream of a small town is filled for development, the town experiences increased flooding. The developer captures the economic value of the filled wetland. The town bears the cost.

Climate change intensifies this dynamic. Warmer temperatures produce more intense precipitation events: the same amount of annual rainfall is concentrated into fewer, heavier storms. Wetlands are the landscape’s natural mechanism for absorbing these pulses. As wetlands are lost, the landscape’s capacity to absorb extreme precipitation declines at the same time that extreme precipitation is increasing. The result is a compounding problem: more water, less absorption, more damage.

The Federal Emergency Management Agency (FEMA) has acknowledged the connection between wetland loss and flood risk in its hazard mitigation planning guidance.¹⁹ The National Flood Insurance Program, which underwrites flood insurance in communities across the country, does not incorporate wetland coverage into its rate-setting methodology. This means that the flood risk created by wetland destruction is socialized through the insurance program rather than internalized by the parties responsible for the destruction.

The prior baseline

The Sackett decision did not initiate wetland loss in the United States. It accelerated a process that has been underway for more than two centuries.

The contiguous United States contained an estimated 221 million acres of wetlands in the 1780s.²⁰ By the 1980s, when the first comprehensive national wetland inventory was completed, approximately 53 percent of those wetlands had been destroyed, primarily through agricultural drainage and urban development. The loss rate peaked in the mid-20th century, when federal policy actively promoted wetland destruction through agricultural subsidies that incentivized drainage of “swampland” for crop production.

The Clean Water Act, beginning in the 1970s, slowed the rate of wetland loss. The Section 404 program, however imperfect, imposed a permitting requirement that forced developers and landowners to at least seek approval before filling wetlands. The “no net loss” policy, adopted by the George H.W. Bush administration in 1989 and maintained by subsequent administrations of both parties, established a goal (though not a legal requirement) of offsetting any permitted wetland destruction through the creation or restoration of equivalent wetland area.²¹

These measures stabilized the rate of loss. They did not reverse it. Net wetland loss continued, though at slower rates than the pre-CWA period. The remaining wetlands, roughly 110 million acres in the contiguous United States, represented the surviving fraction of an ecosystem that had already been reduced by more than half.

Sackett removed approximately half of that remainder from federal protection. The arithmetic is straightforward: the United States lost 53 percent of its wetlands before the Clean Water Act, and the Sackett decision removed federal protection from roughly 50 percent of what remained. The cumulative effect is that approximately three-quarters of the original wetland endowment is either already destroyed or now unprotected by federal law.

The Kavanaugh concurrence

Justice Kavanaugh’s concurrence in Sackett is notable for several reasons. It represents a conservative justice criticizing a conservative majority on environmental grounds. It is written in plain language, without the technical hedging common in concurrences. And it identifies, with specificity, the practical consequences of the majority’s approach.

Kavanaugh wrote that the majority’s continuous surface connection test would exclude from federal protection “a substantial number of wetlands that the Clean Water Act has covered for the last 45 years.”⁴ He noted that the test was inconsistent with the statutory text, which covers “adjacent” wetlands, a term that, as Kavanaugh observed, has always meant “nearby” rather than “touching.” A wetland on one side of a road is adjacent to the river on the other side of the road, even if the road prevents a continuous surface connection.

The concurrence also identified the practical problem with the majority’s test: it ignores how water actually works. Water moves underground. A wetland separated from a river by 50 feet of dry ground may be continuously connected to that river through shallow groundwater. The wetland filters the water that reaches the river. It absorbs the floodwater that would otherwise reach downstream communities. It stores the carbon that would otherwise enter the atmosphere. The fact that the connection is invisible from the surface does not make it less real.

Kavanaugh described the majority’s test as “an overly narrow reading of the Clean Water Act” that would leave “significant gaps in the regulation of wetlands,” gaps that “will not be filled by state regulation.”⁴ He was, by the time of writing, already being proved correct.

What remains

The Clean Water Act has not been repealed. It continues to protect wetlands that have continuous surface connections to navigable waters: the riverine swamps, lakeside marshes, and coastal wetlands that satisfy the majority’s test. For these wetlands, Section 404 permitting remains in effect, and the Army Corps of Engineers retains jurisdiction.

But the wetlands most in need of protection, the geographically isolated, seasonally connected, groundwater-fed systems that perform critical ecological functions without the convenience of a visible surface link to a navigable river, are now protected only if the state where they happen to be located has chosen to protect them. Most have not.

The decision cannot be reversed by executive action. It is a statutory interpretation by the Supreme Court. Changing it requires either a new Supreme Court decision (unlikely in the near term, given the composition of the Court) or an act of Congress amending the Clean Water Act to override the Court’s interpretation. Legislation to do so has been introduced. It has not advanced.

In the meantime, the wetlands remain. They continue to filter water, absorb floods, store carbon, and support the species that depend on them. They do these things regardless of whether federal law recognizes them. The difference is that their destruction, previously subject to federal permitting requirements, can now proceed in much of the country without any regulatory review at all.

The Sacketts wanted to build a house. The Supreme Court let them. In the process, it redrew the boundary of federal environmental protection in a way that will shape water quality, flood risk, biodiversity, and carbon emissions for decades to come.

The case was about a residential lot near a lake in Idaho. Its consequences extend to every watershed in the country.