California Water Views

Federal regulation under the Clean Water Act (CWA) continues to evolve rapidly, creating ongoing uncertainty for project planning and permitting. Recent actions—from new executive directives aimed at expediting permits to updated guidance following the Supreme Court’s Sackett v. EPA decision—are reshaping how the meaning of “Waters of the United States” (WOTUS) is defined and regulated. At the same time, court decisions are narrowing federal authority in some areas while introducing new complexities in others, including changes to CWA National Pollutant Discharge Elimination System (NPDES) permitting requirements and Section 401 water quality certifications.

The regulatory landscape is further complicated by a patchwork of WOTUS definitions across states as a result of prior federal court decisions, ongoing litigation and revisions to nationwide permitting programs that many projects rely on for streamlined approvals. Legal developments involving Endangered Species Act and National Environmental Policy Act compliance and state-level permitting authority are also influencing how projects are reviewed and approved, particularly as agencies adapt to the changing scope of federal jurisdiction.

Looking ahead, additional rulemaking and court challenges are expected to keep the regulatory environment in flux. For project proponents, this uncertainty underscores the importance of proactive permitting strategies, careful planning and close coordination with legal and technical experts to stay abreast of and comply with the ever-evolving state of federal natural resource laws.

In an article for California Water Views – 2026 Outlook, we provide a comprehensive overview of recent WOTUS developments and what they mean for projects.