Water Jurisdiction Reset:
Unlocking Operational Advantages in a Battlespace of State Ire

Introduction

The federal government has clarified the regulatory battlespace, but state‑level friction is already mobilizing, and installations that understand this terrain will hold the operational advantage. For decades, the definition of “Waters of the United States” (WoTUS) has been one of the most unstable areas of environmental law, directly affecting military construction, range operations, stormwater management, and natural resource compliance. On November 20, 2025, the Environmental Protection Agency (EPA) and the Department of the Army published the proposed rule Updated Definition of “Waters of the United States,” intended to realign federal jurisdiction with the Supreme Court’s decision in Sackett v. EPA, and restore predictability across Clean Water Act (CWA) programs.[1] The 2025 Proposed Rule seeks to restore predictability by aligning federal regulations with Sackett, which limits jurisdiction to relatively permanent waters and wetlands with a continuous surface connection. This reset narrows federal authority, reduces regulatory ambiguity, and sets the stage for states to expand their own water protections. Installations that prepare now will be best positioned to leverage its advantages while mitigating the turbulence ahead.

Understanding how this battlespace is shifting begins with grasping what the new rule actually changes and why those changes matter on the ground. The 2025 Proposed Rule represents a major recalibration in federal clean water jurisdiction, narrowing federal authority to relatively permanent waters and wetlands with a continuous surface connection, removing interstate waters as an independent jurisdictional category and clarifying longstanding exclusions. These changes significantly reduce the number of aquatic features subject to CWA permitting, particularly in arid regions where Air Force installations frequently encounter ephemeral washes, isolated wetlands, and man‑made drainage systems. For the Air Force, the proposal offers greater regulatory certainty, fewer permitting delays, and improved predictability for construction and operations.

Public comments on the rule reveal a sharply divided response. Supporters, including agricultural groups, small‑business advocates, and economic development organizations, praised the proposal for eliminating the significant nexus test, reducing regulatory ambiguity, and aligning federal jurisdiction with statutory and judicial limits. Opponents, including states, tribes, and environmental organizations, warned that the rule may leave large portions of the nation’s wetlands and headwaters unprotected, increasing pollution risks and shifting regulatory burdens to states and local communities. For Air Force attorneys, this landscape underscores the need to monitor state‑level regulatory developments, anticipate litigation, and ensure installation planning and environmental compliance remain aligned with both federal and applicable state requirements.

As the rule moves toward finalization, its narrower jurisdiction and clearer definitions will reshape how installations assess water features, plan projects, and avoid unnecessary permitting. Installations that proactively evaluate their aquatic resources and track emerging state responses will be best positioned to maintain compliance while advancing mission priorities. Although the rule remains in proposed form, its core structure aligns with established case law, particularly Sackett, which is already controlling law. The proposal primarily serves to align EPA’s regulations with that precedent. Installations should continue applying Sackett’s relatively permanent and continuous surface‑connection framework while monitoring JAOE updates and the rulemaking process for procedural or implementation changes.

Judicial Foundations of Federal Water Jurisdiction

CWA Framework

The CWA prohibits the discharge of pollutants into “navigable waters,” defined as WoTUS.[2] Congress did not elaborate further, leaving the interpretation to the EPA, the Army Corps of Engineers, and the courts. The statutory framework reflects a “careful balance between Federal authority and State responsibilities over waters,” consistent with the Act’s cooperative federalism design.[3] Historically, federal jurisdiction extended only to waters “navigable in fact,” those waters used or capable of being used as “highways for commerce.”[4]

Key Supreme Court Decisions Shaping WoTUS

Modern WoTUS doctrine is shaped by three Supreme Court decisions: SWANCC, Rapanos, and Sackett.[5] Together, they limit federal jurisdiction to relatively permanent waters and wetlands with a continuous surface connection, a standard the agencies state the 2025 Proposed Rule is intended to implement faithfully.[6] This trilogy now defines the threshold for when Air Force projects require federal permitting.

Overview of the 2025 Proposed Rule

Building on the Supreme Court’s direction in Sackett, the agencies describe the 2025 Proposed Rule as a targeted effort to restore clarity and predictability across CWA programs without restructuring the entire regulatory framework.[7] The rule focuses on jurisdictional categories that Sackett placed in doubt and clarifies several longstanding exclusions.

Elimination of “Interstate Waters” as an Independent Category

One of the most consequential revisions is the removal of “interstate waters” as a standalone jurisdictional basis under 40 C.F.R. Part 120(a)(1)(iii).[8] Historically, interstate waters were regulated even if they lacked a direct connection to traditional navigable waters. The agencies now explain that Sackett requires jurisdiction to be tied to navigability rather than state boundaries, and, therefore, interstate waters cannot serve as an independent basis for federal regulation.[9] This revision narrows federal authority and shifts more responsibility to states for managing waters that cross state lines but lack a continuous surface connection to navigable waters.

Definition of “Relatively Permanent” Waters

For the first time, the agencies propose a regulatory definition of “relatively permanent,” aligning the rule with Sackett’s requirement that jurisdiction extends only to “relatively permanent, standing, or continuously flowing bodies of water.”[10] The proposal clarifies that ephemeral features, common across western Air Force installations, are not subject to CWA jurisdiction.[11] This definition is central to the rule’s structure because it establishes the threshold for determining which tributaries and channels remain federally regulated.

Definition of “Continuous Surface Connection”

The proposal also defines “continuous surface connection,” the second prong of the Sackett test. The agencies provide criteria for evaluating whether wetlands are “indistinguishable” from adjacent relatively permanent waters, including the presence of physical barriers, hydrologic flow, and surface continuity.[12] This definition is intended to reduce ambiguity in wetland determinations and provide clearer boundaries between federal and state jurisdiction.

Revised Exclusions

The 2025 Proposed Rule revises or clarifies several longstanding exclusions from the definition of WoTUS, including those for waste treatment systems, prior converted cropland, ditches, and groundwater. These exclusions reflect the Supreme Court’s repeated insistence that the CWA does not federalize all waters or land features and that Congress preserved substantial state authority over water resources.[13] For Air Force installations, these exclusions are particularly relevant for stormwater systems, wastewater lagoons, and legacy agricultural lands.

While the 2025 Proposed Rule provides a clearer and more constrained framework for determining federal jurisdiction, the administrative record reflects significant disagreement over whether the proposal appropriately implements Sackett and preserves the balance between federal and state authority. These competing perspectives are captured in the public comments submitted to EPA and the Army.

Public Comments on the Proposed Rule

Because the agencies must respond to significant comments, these submissions preview the arguments likely to shape the final rule and subsequent litigation. The proposed WoTUS definition generated substantial public engagement, with commenters sharply divided on whether the rule appropriately implements Sackett and balances federal and state authority. The administrative record reflects both strong support for the proposal’s narrowing of federal jurisdiction and equally strong opposition from states, environmental organizations, and water resource managers concerned about the loss of federal protections.

Comments Supporting the Proposed WoTUS Rule

Several commenters expressed support for the proposed definition, emphasizing regulatory clarity, predictability, and reduced permitting burdens. The U.S. Cattlemen’s Association stated that the proposal “is a necessary step to align with the Supreme Court’s Sackett decision and focus jurisdiction on relatively permanent, truly connected waters.”[14] Supportive commenters also highlighted the value of eliminating the significant nexus test, noting that the new approach “will help end years of speculation about what might be regulated.”[15]

Small‑entity representatives echoed these themes. The Small Business Administration Office of Advocacy explained that the proposed definition “takes meaningful steps toward reducing both the regulatory confusion and unnecessary costs that overbroad [CWA] regulations can impose on small entities.”[16] Economic development organizations similarly welcomed the effort to align the rule with Sackett. Greater New Orleans, Inc. wrote that the proposal would “provide regulatory certainty, reduce litigation risk, and protect the appropriate balance of federal and state authority.”[17]

Collectively, supportive commenters emphasized that clearer jurisdictional boundaries would streamline permitting, reduce delays, and improve long‑term planning, benefits particularly relevant to large infrastructure projects and multi‑jurisdictional development.

Comments Opposing the Proposed WoTUS Rule

Other commenters opposed the proposed definition, arguing that it would significantly narrow CWA protections and undermine water quality, hydrologic integrity, and downstream resilience. Waterkeepers Chesapeake warned that the rule “would move in the exact opposite direction, narrowing federal jurisdiction far further than Sackett demands, at grave expense to people, communities, aquatic ecosystems, and the economy.”[18]

State agencies raised similar concerns. The Colorado Department of Public Health and Environment noted that the proposed “wet season” test could result in “approximately 97% of Colorado’s mapped wetlands” losing federal protection.[19] The New Mexico Environment Department cautioned that the rule “does not reflect the hydrology of arid systems” and that defaulting to non‑jurisdictional status when data are limited “should not be the outcome.”[20] These concerns stem from the proposal’s reliance on a “wet season” assessment window for determining relative permanence, which assumes predictable seasonal hydrology that many arid and semiarid systems lack. States argue that this approach may misclassify wetlands that are ecologically significant but lack consistent seasonal flow.

Conservation groups stressed downstream impacts. The Kentucky Waterways Alliance wrote that the proposal “would remove protections for many of Kentucky’s waterways in significant ways,” including headwaters that supply drinking water to millions.[21] Opposing commenters generally argued that the rule would increase pollution risks, reduce natural flood mitigation, and shift regulatory and financial burdens to states and local communities.

Implications for Air Force Installations

The proposed rule carries significant operational implications for Air Force installations. Because the rule narrows federal jurisdiction and clarifies several ambiguous categories, installations may experience reduced permitting burdens. At the same time, the narrowed federal role is prompting many states to consider expanding their own water programs. However, even in states with delegated CWA authority, that delegation extends only to administering the federal program; it does not authorize states to impose state‑only permitting requirements on federal facilities or to expand federal jurisdiction. As a result, installations should anticipate aggressive state‑level initiatives, policy proposals, and attempts to influence or pressure federal projects, even though such efforts do not create enforceable regulatory authority over federal lands.

Reduced Federal Jurisdiction in Arid Regions

Installations in arid and semi‑arid regions, such as Luke AFB, Nellis AFB, Holloman AFB, and Davis Monthan AFB, stand to see the most immediate impact. These bases contain numerous ephemeral washes and dry channels that previously required case‑by‑case analysis under the significant nexus test. Under the proposed rule, these features are categorically non‑jurisdictional, reducing the need for § 404 permitting and, in some instances, narrowing when § 402 stormwater permitting programs are required. This shift may accelerate military construction timelines and reduce administrative burdens for range improvements and infrastructure projects.

Although these features are non-jurisdictional for purposes of CWA §§ 404 and 301, installations should remember that stormwater programs under § 402 regulate discharges rather than the jurisdictional status of the receiving water, and that other federal statutes—such as the National Environmental Policy Act (NEPA), Endangered Species Act (ESA), and National Historic Preservation Act (NHPA), as well as state water laws may still apply to activities affecting ephemeral channels.

Greater Clarity for Wetlands Near Airfields

The proposed definition of “continuous surface connection” provides clearer guidance for wetlands located near airfields, where runways, taxiways, perimeter roads, and flood‑control structures often interrupt hydrologic flow. Wetlands separated from relatively permanent waters by such features are likely non‑jurisdictional under the proposed rule. This clarity reduces uncertainty for airfield maintenance, safety‑related grading, and drainage projects that previously required extensive coordination with the Corps.

State Policy Responses: Sources and Consequences of Friction

Although the proposed rule narrows federal jurisdiction, it does not prevent states from adopting broader protections for state waters under their own laws. However, states cannot regulate federal facilities under the CWA unless EPA has delegated authority, and even then only to the extent of the federal program, meaning they may regulate discharges into WoTUS but cannot enforce state‑only permitting requirements against federal agencies, even if the state defines ‘waters of the state’ more broadly. As states move to fill perceived regulatory gaps left by the narrowed federal definition, installations should anticipate increased state-level rulemaking activity and, in some jurisdictions, attempts to extend state permitting requirements to federal lands. States with expansive wetland or surface water programs, such as California, New York, New Jersey, Colorado, and New Mexico, are particularly likely to test the limits of their authority, creating potential permitting disputes and compliance uncertainty. Installation legal offices must remain attentive to these developments, ensuring that project planning accounts for federal requirements while also preparing to assess, and, when necessary, contest, state programs that claim applicability to federal facilities.

These jurisdictional changes do not alter other federal or state environmental obligations. Requirements under NEPA, ESA, NHPA, and CWA § 401 remain fully applicable. Likewise, state‑administered stormwater programs under § 402 continue to regulate discharges regardless of whether the receiving feature is jurisdictional under the revised WoTUS definition.

Conclusion

The 2025 Proposed Rule marks a significant recalibration of federal clean water jurisdiction, driven by the Supreme Court’s directive in Sackett and the agencies’ goal of restoring clarity and predictability to CWA implementation. By narrowing WoTUS to relatively permanent waters and wetlands with a continuous surface connection, the proposal substantially reduces the number of features subject to federal permitting, particularly in arid and semi‑arid regions where Air Force installations frequently encounter ephemeral washes, isolated wetlands, and man‑made drainage systems.

For the Air Force, these changes carry meaningful operational benefits. Installations may see fewer § 404 permitting requirements, reduced mitigation obligations, and greater flexibility in planning and executing military construction, airfield improvements, and range operations. Clearer definitions of ditches, waste treatment systems, and artificial conveyances also reduce uncertainty for stormwater management and infrastructure maintenance, supporting more predictable project timelines and mission readiness.

At the same time, the administrative record reflects deep disagreement over the rule’s scope. Supporters view the proposal as a necessary realignment with Sackett that reduces ambiguity and regulatory burden.[22] Opponents warn that the narrowed definition may leave extensive wetlands and headwaters unprotected, particularly in states with limited surface-water programs for large expanses of ephemeral systems.[23] These concerns signal likely litigation and the potential for divergent state regulatory responses, complicating compliance for installations operating across multiple jurisdictions.

Ultimately, the 2025 Proposed Rule presents both opportunities and challenges. While it narrows federal jurisdiction in ways that may streamline Air Force project delivery, it also shifts greater responsibility to states, heightening the importance of understanding local regulatory landscapes. Air Force attorneys should monitor the rulemaking closely, anticipate potential judicial review, and prepare for updated guidance from the Corps and EPA. As the definition of WoTUS continues to evolve, proactive legal engagement will remain essential to sustaining mission execution while ensuring compliance across federal and state water‑resource regimes. Although states may attempt to expand their programs in response to the narrowed federal role, federal facilities remain subject only to federal requirements.

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Practical Steps

Understand Your Installation’s Aquatic Landscape. Installations should maintain an up‑to‑date understanding of the aquatic features present on the installation, including relatively permanent waters, wetlands, ephemeral channels, artificial conveyances, and stormwater infrastructure. Accurate mapping and hydrologic characterization are essential for planning, project review, and early identification of activities that may implicate CWA requirements.

Conduct Internal Jurisdictional Determinations. Under DAFMAN 32‑7003, “[s]ite level jurisdictional delineations of WoTUS are mandatory for proposed development activities that may affect wetlands, streams, and water bodies, and are the responsibility of the proponent as part of project costs.”[24] To that end, “[t]he proponent of any activity that may affect known or suspected WoTUS should conduct a jurisdictional delineation utilizing the criteria approved by the [EPA] and affirmed by the U.S. Army Corps of Engineers (USACE).”[25] This framework enables installations, working with Civil Engineer and Air Force Civil Engineer Center (AFCEC)—to make internal jurisdictional assessments for most routine or low‑risk activities, avoiding the need to request an official jurisdictional determination (JD) from the Army Corps and the project delays associated with Corps engagement.

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Integrate WoTUS Changes into Installation Planning

1. Update Environmental Baseline Surveys, NEPA analyses, and project‑level environmental reviews to reflect the revised WoTUS definitions. These efforts can include updates to maps, hydrologic descriptions, and impact analyses.
2. Review military construction (MC), facilities sustainment, restoration and modernization (FSRM), and range projects early. Projects that might have required a CWA permit under the previous WoTUS framework may no longer require a permit in the post-Sackett environment.
3. Coordinate with CE, AFCEC, and Project Managers. Legal offices should ensure that planners and engineers understand the current scope of CWA jurisdiction and the mechanisms to request a JD from the USACE, if necessary.

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Prepare for Increased State Engagement

AFCEC’s Legislative and Regulatory Engagement Division (AFCEC/CZP) monitors state legislative and regulatory developments that have the potential to impact the Department of the Air Force (DAF) mission. These state developments include proposals to expand wetland protections, administer new permitting programs, and extend the enforcement of clean water laws to so-called “waters of the state.” JAOE’s Eastern Regional Counsel Office and Western Regional Counsel Office are embedded within AFCEC/CZP and are a resource to installation legal offices for any issues relating to the emergence of new state environmental laws and their application to federal installations.

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Strengthen Documentation and Recordkeeping

Installations should maintain a central repository of JDs and other hydrologic data for installation aquatic features. This documentation will prove critical in the event of regulator engagement, enforcement action, or litigation under the CWA.

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Anticipate Litigation and Regulatory Uncertainty

Legal offices should anticipate a period of regulatory uncertainty as state and federal regulators test the bounds of recently narrowed CWA jurisdiction. Legal offices should proactively advise commanders on evolving permitting requirements and potential impacts to construction projects and installation infrastructure that have historically relied on CWA permits. Installation legal offices are encouraged to reach out to JAOE’s Regional Counsel Offices for assistance engaging with regulators on matters of CWA compliance and enforcement.

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Provide Training and Outreach

1. Train CE, Environmental, and Project Management Personnel
2. Develop Quick‑Reference Tools
3. Engage Paralegals

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For commanders, the key operational takeaway is that the proposed rule may reduce federal permitting delays for many projects, particularly in arid regions, but it also increases the importance of monitoring state regulatory developments and maintaining strong documentation of aquatic features. Early coordination with CE, AFCEC, and legal offices will be essential to avoid project delays and ensure compliance during this period of regulatory transition.

About the Authors

Ms. India S. Nicholson, USAF

(B.A., University of West Florida, Pensacola, Florida; M.A., University of West Florida, Pensacola, Florida; J.D., Ohio Northern University, Ada, Ohio; M.S., Air University, Maxwell Air Force Base, Alabama) is the Senior Attorney for Water Issues, Environmental Law Field Support Center, Operations and International Law Directorate, Joint Base San Antonio-Lackland, Texas.

Major Stephen D. Tomasek, USAF

(B.A., University of California, Berkeley, California; J.D., Georgetown University Law Center, Washington, D.C.; LL.M., The George Washington University, Washington, D.C.) is the Regional Counsel at AF/JAOE’s Western Regional Counsel Office, Travis AFB, California.

Technical Sergeant Jaqlynn M. Bieu, USAF

(A.A., Criminal Justice, Community College of the Armed Forces, A.A., Paralegal Studies, Community College of the Armed Forces) is the Noncommissioned Officer in Charge of the Environmental Law Field Support Center, Environmental Law Field Support Center, Operations and International Law Directorate, Joint Base San Antonio-Lackland, Texas.

Endnotes