If there were an Olympic event for regulatory whiplash, the phrase “waters of the United States”, or WOTUS, would already have a gold medal, a sponsorship deal, and probably its own documentary. Few phrases in environmental law have caused more confusion for farmers, builders, manufacturers, landowners, conservationists, and government staff. Now the U.S. Environmental Protection Agency and the Department of the Army are trying once again to redraw the line.
In late 2025, the agencies proposed a new rule to revise the definition of waters of the United States under the Clean Water Act. The stated goal is straightforward enough: fully implement the Supreme Court’s 2023 decision in Sackett v. EPA, reduce confusion, and create a definition that regulators and the regulated public can actually use without needing a philosophy seminar and a wetland consultant every Tuesday. The bigger question is whether the proposal truly delivers clarity, or simply narrows federal jurisdiction so much that major streams and wetlands are left to a patchwork of state rules.
This proposed WOTUS rewrite matters because the definition determines where federal Clean Water Act protections apply. It affects permits for dredging and filling wetlands, discharges to surface waters, project timelines, compliance costs, and the reach of environmental enforcement. It also affects how much responsibility shifts to states and tribes. Supporters say the proposal is a long-overdue correction that follows the law and respects property rights. Critics say it could leave more waters vulnerable to pollution and destruction. Both sides, for once, agree on one thing: the stakes are huge.
What “Waters of the United States” Actually Means
WOTUS is the legal gateway to federal jurisdiction under the Clean Water Act. If a river, stream, lake, wetland, or similar water feature counts as a water of the United States, then certain federal permitting and pollution-control requirements kick in. If it does not, federal jurisdiction may disappear, even though state or tribal law may still apply.
That line matters in the real world. A developer planning a subdivision, a farmer cleaning a ditch, a mining company expanding operations, a pipeline builder crossing a wet area, or a municipality upgrading drainage infrastructure may all need to know whether a particular feature is federally protected. If the answer is yes, permitting can take longer and cost more. If the answer is no, the project may move faster, but environmental safeguards may depend more heavily on state, tribal, or local rules.
The trouble is that Congress used broad language in the Clean Water Act, and the courts have spent decades arguing about what that language covers. Wetlands next to streams, intermittent tributaries, ditches, isolated waters, and interstate features have all become part of the legal tug-of-war. WOTUS has been revised multiple times across administrations, challenged in court repeatedly, and interpreted differently depending on where you live. That is not a recipe for confidence. It is a recipe for migraines.
Why EPA and the Army Are Rewriting the Rule Again
The immediate driver is the Supreme Court’s decision in Sackett v. EPA. In that case, the Court rejected the broader “significant nexus” test and held that the Clean Water Act extends only to wetlands that are, as a practical matter, indistinguishable from covered waters because they have a continuous surface connection to those waters. Put less like a judicial opinion and more like plain English: if the wetland does not really touch the covered water in a way that makes the boundary hard to see, federal jurisdiction becomes much harder to claim.
After Sackett, EPA and the Army issued a 2023 conforming rule and then a 2025 guidance memo on how to interpret “continuous surface connection.” But that did not end the drama. Ongoing litigation left the agencies applying different regulatory regimes in different states. In some states, the amended 2023 rule still applies. In others, the agencies are using the pre-2015 regime combined with Sackett. That means the same wet feature could be analyzed under different approaches depending on the map, the courthouse, and your luck. The 2025 proposed rule is supposed to replace that split-screen legal universe with one uniform national standard.
EPA and the Army also say the proposal is intended to provide more predictability, reduce permitting burdens, and better reflect the limits of federal power under the Clean Water Act. That sounds tidy on paper. In practice, the proposal makes several major revisions that would narrow federal reach in important areas.
The Biggest Proposed Changes to the WOTUS Definition
1. Interstate waters would no longer be a standalone category
One of the most notable revisions is the proposal to remove interstate waters as an independent basis for federal jurisdiction. Crossing a state line would no longer be enough by itself. Instead, an interstate water would have to fit another jurisdictional category, such as being a traditional navigable water or a qualifying tributary. The agencies say this change better aligns the rule with Sackett and the text of the Clean Water Act.
Supporters view this as common sense. Critics see it as a quiet but meaningful contraction of federal oversight, especially in places where waters cross borders but may not satisfy the newer, narrower tests.
2. “Relatively permanent” gets a tighter definition
The proposal would define relatively permanent waters as standing or continuously flowing bodies of surface water that are year-round or flow at least during the wet season. Ephemeral features, meaning waters that appear only in direct response to rainfall, would generally not count. That sounds simple until you remember the United States has deserts, mountains, snowmelt systems, monsoonal patterns, coastal marshes, and every kind of hydrologic mood swing imaginable.
The wet-season concept is meant to account for regional differences, but it also introduces a new layer of technical analysis. Regulators may need precipitation patterns, imagery, stream data, and historical records to decide whether a feature qualifies. So yes, the proposal aims for clarity, but it may still leave plenty of room for argument in places where water shows up seasonally, inconsistently, or just often enough to be annoying.
3. Tributaries must connect through relatively permanent flow
The proposed rule would require a tributary to have relatively permanent flow and connect to downstream traditional navigable waters through waters or features that also convey relatively permanent flow. If the connection runs through a non-jurisdictional break such as a culvert, debris field, or non-relatively permanent feature, federal jurisdiction upstream may be severed. This is a big deal in arid and semi-arid regions, where channels can shift between flowing, trickling, and looking like nature forgot them for a season.
That may reduce federal jurisdiction over some upstream reaches that used to be argued into coverage. Industry groups tend to like that. Environmental advocates do not send it valentines.
4. Adjacent wetlands would need to touch and hold surface water during the wet season
For adjacent wetlands, the proposal leans heavily into the agencies’ 2025 guidance. A wetland would need a continuous surface connection to a jurisdictional water, and the agencies interpret that to mean two things: the wetland must abut, or physically touch, the water, and it must have surface water at least during the wet season.
This is one of the most consequential parts of the proposal. It narrows the universe of federally protected wetlands by excluding many features that may be hydrologically important but are not visibly connected in the right way for the required duration. The agencies say this follows Sackett. Critics argue it ignores how wetlands function on the landscape and how water actually moves beyond neat legal categories.
5. Certain ditches would be excluded more clearly
Ditches have long been one of WOTUS’s greatest hits in the category of “things everyone fights about.” The proposal would exclude ditches, including roadside ditches, that are constructed or excavated entirely in dry land. It also proposes a clearer definition of “ditch” as a constructed or excavated channel used to convey water.
For farmers, local governments, stormwater agencies, and transportation departments, this could be one of the most practical changes in the rule. The agencies are trying to reduce the old mess where some ditches were obviously out, some were maybe in, and some lived in a bureaucratic gray zone where nobody wanted to be the first person to make a wrong call.
6. Prior converted cropland gets a friendlier treatment
The proposal would return to an approach that gives more clarity for prior converted cropland. It adopts an abandonment-style concept rather than a simpler change-in-use approach. In general, this is meant to make it easier for agricultural landowners to understand when converted cropland stays excluded and when wetlands may be recaptured into Clean Water Act jurisdiction if the land is abandoned and wetland conditions return.
Agricultural groups have pushed for more certainty here for years. From their perspective, land that was lawfully altered and long used for farming should not suddenly become a federal permitting trap because a map changed or a rule got rewritten again.
7. Groundwater would be expressly excluded
Groundwater has not historically been treated as WOTUS, but the proposal would make that explicit by adding a groundwater exclusion, including groundwater drained through subsurface drainage systems such as tile drains. The agencies note that surface expressions of groundwater can still matter if they emerge and become part of a qualifying surface water, but groundwater itself would remain outside the definition.
That may sound technical, but it matters a lot in agriculture and land development, where subsurface drainage can be central to how property is used and regulated.
8. Waste treatment systems would be clarified
The proposal would continue excluding waste treatment systems while clarifying what counts as part of such a system. That includes lagoons and treatment ponds designed to convey, retain, settle, or remove pollutants before discharge. This revision is aimed at clarity rather than a dramatic shift, but for regulated facilities, clarity can be worth its weight in consultants.
Why Supporters Like the Proposal
Supporters say the rule finally aligns federal regulation with the Supreme Court’s direction. From that viewpoint, the agencies are not gutting the Clean Water Act; they are acknowledging that federal power has legal limits and that Sackett drew a narrower line. Small business groups, agriculture interests, homebuilders, landowners, and many Republican officials have praised the proposal for promising lower compliance costs, fewer permits, less delay, and less uncertainty.
There is also a federalism argument behind the support. EPA and the Army emphasize that states and tribes can regulate waters more broadly under their own laws. In other words, supporters say the sky is not falling; responsibility is simply shifting closer to local decision-makers who know local conditions better. To them, that is not deregulation so much as a reset.
Why Critics Are Alarmed
Critics respond that this is not merely a tidy legal cleanup. They argue it is a substantial narrowing of federal protections for wetlands and streams, especially seasonal waters and wetlands that are ecologically significant but do not meet the proposal’s stricter tests. Environmental groups warn that reduced federal jurisdiction could mean more filling, dredging, pollution, and habitat loss, with uneven protections depending on the state.
Another concern is administrative burden. If federal jurisdiction recedes, states and tribes may be expected to fill the gap, but not all have the same laws, funding, staffing, or political appetite. That could create a map of protection where one state acts aggressively and the next one shrugs while a wetland quietly disappears beneath a parking lot.
Even some practitioners who favor a narrower rule say implementation could still be messy. Terms like “wet season,” “relatively permanent,” and “abutting” may be clearer than older standards, but they still invite field judgment, data disputes, and case-by-case fights. In regulatory law, “clearer” does not always mean “clear.” Sometimes it just means the argument moved to a different paragraph.
Real-World Examples of What This Could Mean
Example one: A roadside ditch excavated entirely in dry land is more likely to be excluded under the proposal, which could simplify maintenance work for local governments.
Example two: A seasonal wetland near a stream may no longer be federally protected if it does not physically touch the jurisdictional water and hold surface water for the required duration during the wet season.
Example three: A farm field with tile drainage may benefit from the explicit groundwater exclusion, reducing uncertainty about whether subsurface drainage features pull federal jurisdiction onto land that is otherwise outside WOTUS.
Example four: An interstate stream crossing state lines would not be federally regulated just because it crosses the border. It would need to qualify under another category.
Example five: A treatment lagoon designed to manage wastewater before discharge would likely remain excluded if it fits within the clarified waste treatment system language.
What Happens Next?
The proposal was published in the Federal Register in November 2025, and the public comment period closed in early January 2026. EPA and the Army also held listening sessions and collected extensive feedback from states, tribes, local governments, industry, agriculture groups, environmental organizations, and the public. As of now, the rule remains a proposal, not the final word. That means the current patchwork created by litigation and prior rules still matters until a final rule is issued and survives whatever lawsuits come next. And yes, everyone expects lawsuits. It would be more surprising if WOTUS suddenly became boring.
The agencies say they want a durable final definition. The challenge is that durability in WOTUS-land is a little like permanent marker on a whiteboard: impressive for a while, but rarely forever.
Bottom Line
The EPA and Army proposal represents a major effort to narrow and clarify the federal definition of waters of the United States after Sackett. It would tighten the tests for tributaries and adjacent wetlands, remove interstate waters as a standalone category, clearly exclude more ditches and groundwater, and give agriculture and regulated industries more predictable exclusions in several areas.
Whether that sounds like a victory or a warning siren depends on where you sit. For landowners, developers, and many businesses, the proposal may mean fewer permits, faster project planning, and clearer boundaries. For environmental advocates and some regulators, it may mean fewer wetlands and streams protected under federal law and more pressure on states and tribes to fill the gap. The safest conclusion is this: if you work anywhere near land, water, permits, or infrastructure, WOTUS still matters enormously, and this latest rewrite could change the compliance map in very real ways.
Experiences Related to “EPA, Army Propose Revisions to Waters of the United States Defini”
One of the most revealing things about the WOTUS debate is how different the experience feels depending on who is standing in the mud. A consultant hired by a developer may see the proposed revisions as relief from years of unpredictable jurisdictional calls. That consultant might remember projects where clients spent months and serious money trying to determine whether a feature was a regulated wetland, only to end up with a conclusion that felt more like legal astrology than scientific certainty. For that crowd, a narrower rule is not just policy; it is the difference between a project moving in one season or sitting in limbo through two fiscal years.
Farmers and ranchers often describe the issue in even more personal terms. For them, a ditch is not a law school exam. It is something that either drains a field, floods a field, or ruins a weekend. Many agricultural landowners have long said they need a rule they can understand without hiring a team of specialists every time they clean out a drainage feature or evaluate acreage that was converted decades ago. The proposed treatment of ditches, tile drainage, and prior converted cropland will likely feel, to many of them, like overdue recognition that agriculture works on seasonal realities, not tidy legal abstractions.
On the other side, environmental advocates, watershed groups, and many local residents have their own lived experience. They know what happens when a wetland gets filled, a stream gets channelized, or a seasonal water is treated as disposable because it is not flowing on the exact day someone takes a picture. They talk about neighborhoods that flood more often, drinking water sources that become dirtier, and wildlife habitat that disappears in increments so small each time that nobody notices until the whole system is weaker. To them, the proposed rule does not feel like clarity. It feels like one more step away from a national floor of protection.
State and tribal officials often have the most complicated experience of all. They are the ones asked to manage the practical fallout when federal rules change, court injunctions split the map, and stakeholders demand fast answers. Some welcome stronger state authority. Others worry about inheriting more responsibility without matching money, staff, or political support. In many places, the real experience of WOTUS is not ideological at all. It is a constant scramble to answer basic questions from landowners, permit applicants, and local governments while the legal definition keeps moving.
That is why this proposal matters beyond the Federal Register. It is not just about words in a regulation. It is about whether people on the ground experience the Clean Water Act as understandable and workable, or as a rolling national argument with mud on its boots. In truth, both things can be real at once. The proposal may indeed make some jurisdictional calls easier. It may also leave more waters outside federal protection. And that tension is exactly why the WOTUS fight never really stays inside Washington. It always ends up back in a field, at a construction site, beside a creek, or in a community asking a simple question with a very expensive answer: does this water count?
