EPA and Army Propose Update to the Definition of WOTUS

On November 17, 2025, the U.S. Environmental Protection Agency (“EPA”) and the U.S. Department of the Army (“the agencies”) released a proposed rule that updates the definition of “Waters of the United States” (“WOTUS”) under the Clean Water Act (“CWA”). The proposal aims to bring the regulations into compliance with the U.S. Supreme Court’s decision in Sackett v. EPA, 598 U.S. 651, 143 S. Ct. 1322 (2023).

This article summarizes the proposed changes and why they matter for landowners, developers, and regulated entities. For additional background, readers may want to explore earlier WOTUS analysis on this website, including discussions of the Sackett decision and the history of the “significant nexus” test.

---

Why the Agencies Are Updating the Definition of WOTUS

Before Sackett, agencies used the “significant nexus” test to determine federal jurisdiction. Under that test, waters could fall under the CWA if—alone or combined with similar waters—they significantly affected the integrity of traditionally navigable waters. This standard came from Rapanos v. United States, 547 U.S. 715, 719, 126 S. Ct. 2208, 2214 (2006) (Kennedy, J., concurring).

The Supreme Court rejected the significant nexus test in Sackett. The Court held that the CWA covers only those wetlands with a continuous surface connection to waters that are themselves WOTUS. The connection must make the wetlands “indistinguishable” from those waters. Sackett, 598 U.S. at 684.

To follow Sackett, the agencies now propose several key regulatory revisions.

---

Key Proposed Changes

1. New Definition of “Relatively Permanent”

The prior regulations used the phrase “relatively permanent” but did not define it. The proposed rule defines it as:

• Standing or continuously flowing bodies of surface water
• That exist year-round or at least during the wet season

This means seasonal waters can still qualify as WOTUS if they persist during the wet season.

---

2. Clarified Definition of “Continuous Surface Connection”

The agencies propose that a continuous surface connection exists when waters:

• Have surface water at least during the wet season, and
• Abut (touch) a jurisdictional water

The proposal emphasizes that the water body must directly touch the jurisdictional water. Any land feature between them breaks the surface connection.

---

3. Other Important Term Updates

The proposed rule also revises several additional terms:

Removal of “Intrastate”

• The term “intrastate” would be removed.
• This makes clear that a water body is not WOTUS solely because it crosses state lines if it does not otherwise meet the criteria.

Revised Exclusion for “Ditches”

• Only ditches constructed or excavated entirely on dry land qualify for exclusion from WOTUS.

Updated Exclusion for “Prior Converted Cropland”

• The agencies clarify when abandonment of prior converted cropland may allow reclassification as a wetland.

Expanded Definition of “Waste Treatment Systems”

• The proposal further explains which waste treatment systems fall outside the definition of WOTUS.

---

Purpose of the Proposed Changes

These revisions aim to help States, Tribes, and private parties understand which water bodies fall under the CWA after Sackett. Clearer definitions allow landowners and regulators to make informed land?use and water?use decisions with greater confidence.

---

What Happens Next?

The proposed rule has been submitted for publication in the Federal Register. A 45-day public comment period will begin once publication occurs. A final rule will be released after the agencies review and consider submitted comments.

Litigation over WOTUS is expected to continue, and this rulemaking will likely be part of that ongoing legal landscape.

For further context, readers can review other WOTUS?related analyses on water-law.com, which discuss both the long regulatory history leading to Sackett and the challenges that continue to shape federal jurisdiction over water resources.

In a significant decision, the United States Supreme Court has narrowed the scope of the National Environmental Policy Act (NEPA). This ruling came from the case Seven County Infrastructure Coalition v. Eagle County.

What is NEPA?

NEPA is a law that requires federal agencies to consider the environmental impact of their actions. For any major federal action that significantly affects the environment, an agency must draft an Environmental Impact Statement (EIS). This report ensures that the agency carefully considers the environmental impacts and makes this information available to the public.

The Case

The case involved the U.S. Surface Transportation Board (the Board), which oversees the construction of new railroad lines. The Board approved an 88-mile railroad line in Utah’s Uinta Basin to transport crude oil. However, a Colorado county and several environmental groups challenged this decision. They argued that the EIS did not adequately consider the environmental effects of increased oil drilling in the Uinta Basin or the greenhouse gas emissions from refining the oil.

The Court’s Decision

The U.S. Court of Appeals for the D.C. Circuit initially agreed with the challengers and vacated the EIS and the Board’s approval. However, the Supreme Court overturned this decision. Justice Kavanaugh, writing for the majority, emphasized that NEPA is a procedural statute. This means that as long as an agency prepares an adequate report, courts should defer to the agency’s decisions.

Justice Kavanaugh explained that agencies make many fact-dependent, context-specific, and policy-laden choices when assessing environmental effects. Courts should not micromanage these choices as long as they are reasonable. This effectively narrows the scope of NEPA.

Implications

The Supreme Court’s decision means that agencies do not need to consider the environmental effects of separate projects during the NEPA process. This ruling aims to prevent citizens from using NEPA to delay or block federal projects based on the environmental effects of unrelated projects.

Justice Sotomayor, joined by Justices Kagan and Jackson, agreed with the decision but wrote a separate opinion. They believed the case should have been decided on narrower grounds, focusing on the Board’s lack of authority to reject the project based on third-party actions.

Conclusion

This decision narrows the scope of review required under NEPA. It will be interesting to see how federal agencies conduct their NEPA analysis going forward.

The 2025 Nevada Legislative Session has begun. It’s looking like a busy session for water bills. Four bills caught my attention and we thought we should share them with you!

Assembly Bill 134

AB 134 proposes to amend NRS Chapter 533 to allow owners of a perfected water rights to submit water conservation plans to the State Engineer for approval. The goal of the bill is to “promote and encourage the conservation, development, augmentation and efficient use of the waters of this State through the use of practices for the voluntary conservation of water, including, without limitation, water conservation plans, crop rotation or conversion, improved irrigation practices and reductions in surface and seepage losses of water at the place of use of water.”

The main perk for those with approved conservation plans is that their water rights are not subject to abandonment pursuant to NRS 534.090.

Assembly Bill 104 and Senate Bill 36

AB 104 proposes to establish an Account for Retiring Water Rights and the Nevada Voluntary Water Rights Retirement Program (“Program”) to be administered by the Director of the State Department of Conservation and Natural Resources (“Director”).

The Program would allow the Director to accept applications for the purchase and retirement of water rights until June 30, 2035. Under this proposal, the State Engineer will retire the water rights that are purchased and the water will not be available for appropriation. SB 36 has nearly identical provisions but calls the Program the Nevada Water Buy-Back Initiative.

Also contained in AB 104 is a section proposing to change the name of temporary permits to revocable permits. There is also a section prohibiting domestic well drilling if the property is within 1,250 feet of a public entity service line.

Assembly Bill 265

            AB 265 proposes to amend NRS Chapter 533 to require the Nevada Division of Water Resources to notify water appropriation applicants if a committee is assigned to review the application. The bill places deadlines on the committee to complete the application review within 30 days after the protest deadline passes if no protests are timely filed, and within 60 days if a protest is received. The bill goes on to set deadlines for the State Engineer to act on other processes including reviewing applications for water use, extension of time applications, and confirming reports of conveyance to update water right ownership inforamation.

Lastly, under AB 265, the State Engineer will be required to notify a permit holder 30 days before the due date that a permit will be held in cancellation if a proof of completion of work or proof of application of water to beneficial use is not filed.

Take Aways from the 2025 Legislative Session

            These bills illustrate the increasing necessity to conserve water resources in Nevada while safeguarding senior priority water rights. Additionally, AB 265 addresses the increasing concern over the backlog in the State Engineer’s office. It sets deadlines to allow for the prompt administration of water rights. Now it will be up to the State Legislature and the Governor to decide if these bills will become law.

---

The McCarran Amendment

A current Ninth Circuit Case could upset pre-1952 water rights adjudications in certain circumstances!

Enacted by Congress in 1952, the McCarran Amendment, 43 U.S.C. § 666, waives the United States’ sovereign immunity in state court water rights adjudications. The Amendment acknowledges the power of a state to regulate ownership and use of the waters within its boundaries. This allows the federal government to be joined as a defendant in a suit to determine ownership and priority of water rights from a particular source.

But, what happens in the circumstance where vested water rights were adjudicated before the McCarran Amendment was enacted? If the federal government could have joined state adjudication proceedings in the past, and chose not to, can they still assert reserved water rights to the fully adjudicated water source?

The Challenge

That is precisely the issue that arose in the Nevada federal court case Backer Ranches, Inc. v. Haaland. In Baker Ranches, owners of decreed water rights to Baker and Lehman Creeks sued the United States for interfering with their water rights to the creeks.

The state court adjudication establishing the owner’s water rights to Baker and Lehman Creeks occurred in 1934, before the McCarran Amendment. Because the federal government had sovereign immunity to state court proceedings concerning water rights at the time, the federal government was not a party to the adjudication, though it was informed and provided with updates about the proceedings.

Years later, the federal government allegedly began to divert the flows of the creeks, interfering with the plaintiffs’ decreed water rights and triggering the lawsuit. The federal government moved to dismiss the case, claiming that it had reserved water rights superior to the plaintiffs and that the court lacked subject matter jurisdiction because the federal government was not a party to the 1934 adjudication and had sovereign immunity.

Plaintiffs argued that the McCarran Amendment waived federal sovereign immunity and that the state adjudication should control ownership and use of the water at issue. The court ultimately sided with the federal government, noting that the waiver of sovereign immunity found in the McCarran Act only applied to circumstances where the adjudication of water rights is comprehensive – i.e. when all parties asserting water rights are able to participate in the adjudication.

District Court Findings

The court found that the federal government’s reserved water rights were not part of the 1934 adjudication and that the federal government had not waived its sovereign immunity. Hence, the court dismissed the case, finding that it lacked subject matter jurisdiction. The court’s decision to dismiss the case is currently being appealed to the Ninth Circuit Court of Appeals.

If the court’s decision in Baker Ranches is upheld it has the potential to upset what has been considered settled priorities for water use throughout the arid western United States. If upheld, the federal government will have the ability to assert reserved water rights to a water source that has already been adjudicated in state court if the adjudication occurred before the passage of the McCarran Amendment and the federal government was not a party. In certain circumstances, the result could be as drastic as the complete loss of an individual’s water use.

Schroeder Law Offices is happy to review your circumstances with you.

In 2019, we previously posted a blog on the Public Trust Doctrine in Nevada which you can find here. Since then, the Nevada Supreme Court made its decision in Mineral Cty. v. Lyon Cty., 136 Nev. 503, 473 P.3d 418 (2020). We provide a brief recap of the Public Trust Doctrine and an update on the status of the doctrine in Nevada.

The Nevada Supreme Court formally recognized the Public Trust Doctrine in 2011 in Lawrence v. Clark County. However, the Court in Lawrence only recognized the doctrine in the context of navigable waters. In Mineral County, the Court later clarified that the doctrine applies to all waters within the state, whether navigable or non-navigable. The Court also adopted the position that the Public Trust Doctrine has been in place in Nevada since statehood, despite the doctrine not being formally acknowledged until Lawrence.

What is the Public Trust Doctrine?

The public trust doctrine “generally acts as a restraint on the state in alienating public trust resources.” Id. at 509. However, arguably the doctrine has broader implications than only the alienation of public resources by the State. The doctrine enshrines the principle that the public trust resources are owned by the State, and the State cannot use them for just any purpose. Rather, the State acts as a fiduciary. This means the State must use and maintain public trust resources for the benefit of the public. Therefore, because the State owns all the water of the State and holds those waters in trust for the public, the State has a duty to protect the water from misuse or contamination. As an acting fiduciary, the State’s protection is for the benefit of current and future residents of the State.

How does the decision in Mineral County affect your water rights?

The Court in Mineral County found that even though the Public Trust Doctrine “applies to all waters within the state, including those previously allocated under prior appropriation,” the doctrine does not allow for the reallocation of rights settled under the doctrine of prior appropriation. Id. at 506. The Court reasoned that the “state’s statutory water scheme [which is based on the doctrine of prior appropriation] is consistent with the public trust doctrine by requiring the State Engineer to consider the public interest when allocating and administering water rights.” Id. / The Court went on to explain, “in recognizing the significance of finality in water rights, our Legislature has expressly prohibited reallocating adjudicated water rights that have not been otherwise abandoned or forfeited in accordance with the state’s water statutes.” Id.

Due to the Mineral County decision, courts in Nevada will recognize the Public Trust Doctrine as it applies to the disposition of water rights by the State under the state’s statutory scheme. The Court in Mineral County cautioned “that rights holders must continually use water beneficially or lose those rights.” Id. at 518. If you need assistance ensuring your water is placed to beneficial use, research attorneys that can help you comply with State regulations.

Conjunctive management recognizes there may be a hydrological connection between groundwater and surface water within an area. This means, drawing down groundwater may affect the availability of surface water, and vice versa. In prior appropriation states like Nevada, where senior water rights have priority, surface water rights will generally trump groundwater right. In January 2024, the Nevada Supreme Court weighed in on Nevada’s conjunctive management law.

Points of Contention

With limited water availability in the arid west, it is increasingly necessary to manage both groundwater and surface water as a single management unit to protect senior water rights. However, there is an understandable reluctance on the part of some junior water rights holders to curtail water use that has gone unchecked for decades.

One point of contention is whether the best available science supports the curtailment of a junior water right– does the best available science support finding a specific groundwater use is depleting the source of a senior surface water right? How much can a junior water rights holder still use and not affect the senior water rights? The Nevada State Engineer will determine what constitutes “best available science.”  Is it a full-blown scientific model, or will something less suffice?

A second point of contention has been whether the State Engineer has the authority to manage the waters of the State conjunctively. We finally have the answer: In January 2024, the Nevada Supreme Court issued its decision in Sullivan v. Lincoln County Water District recognizing the power of the State Engineer to conjunctively manage surface waters and groundwater. Case Nos. 84739, 84741, 84742, 84809, 85137, 2024 Nev. LEXIS 4 (Jan. 25, 2024).

The Court’s Decision

In reaching their decision, the Court primarily relied on provisions of the Nevada Revised Statutes (NRS) (state.nv.us) prohibiting the impairment of vested/existing water rights, “regardless of the water source.” The Court noted that “[a]ll statutorily granted water rights in Nevada are given subject to existing rights” and “[b]ecause vested water rights by definition exist prior to the grant of statutorily granted water rights… no statutorily granted water right may impair vested water rights.” Id. (citations omitted). In sum, the Court found that no matter the source, ground or surface water, the State Engineer must not allow any impairment of vested water rights. Hence, the State Engineer must have the power to conjunctively manage both sources of water in Nevada.

The Court’s decision also recognizes the legislative policy declared at NRS 533.024 “which require the State Engineer to ‘consider the best available science in rendering decisions concerning the available surface and underground sources of water’ and ‘[t]o manage conjunctively the appropriation, use and administration of all waters.” As such, the Court notes these policy declarations support the finding that the State Engineer has power to conjunctively manage the waters of the State of Nevada, decisively settling years of litigation over the matter.

What’s Next?

For years the State Engineer attempted to conjunctively manage but was hamstrung by scientific uncertainty regarding the hydrological connection between groundwater and surface water sources, leading to exhaustive litigation concerning the State Engineer’s management orders. The new Model on the Humbold River, reportedly nearing completion, will be integrated into the State Engineer’s future orders that will likely be further tested in the courts. Likewise, submission of Scientific Reports in the Lower White River Flow system were presented to the Nevada Court that will now determine if these reports are sufficient substantial evidence to support the State Engineer’s regulation orders.  It will be interesting to follow the litigation to see what level of “best available science” will withstand the scrutiny of the courts.

You might be interested in this article about Nevada Water Law.