U.S. Army Corps of Engineers Proposes to Reissue and Modify Nationwide Permits

On June 18, the U.S. Army Corps of Engineers (Corps) published a Notice of Proposed Rulemaking that would reissue 56 of its existing Nationwide Permits (NWPs), introduce one new NWP, and make targeted modifications to the scope of certain NWPs and their terms. Key updates include a new NWP for fish passage improvements and changes to reflect recent litigation outcomes — including rescinding Florida’s program authorization and the NWPs for finfish and (in part) shellfish mariculture activities — as well as clarifying the trigger for state water quality certification under Section 401. The Corps also proposes, among other changes, an express prohibition on combining acreage limits when using more than one NWP to purportedly authorize a greater impact, and requiring restoration of areas affected by construction mats.

Background

Nationwide Permits are a form of general permit issued under Section 404 of the Clean Water Act and Section 10 of the Rivers and Harbors Act of 1899 to authorize categories of activities that discharge to waters of the United States, but result in only minimal individual and cumulative adverse environmental effects. NWPs are typically reissued every five years, and the NWPs currently in effect would expire in March 2026.

The following summarizes key changes for which stakeholders may be interested in submitting comments to the Corps.

Proposed New and Rescinded NWPs

• New NWP A (Fish Passage Improvement): The proposed new NWP A would authorize activities aimed at improving the passage of fish and other aquatic organisms, including culvert replacements, the installation of both technical and nature-like fishways, construction of bypass channels, fish screens, and modifications to tidal gates. The permit is limited to projects resulting in the loss of no more than one acre of waters of the United States, and requires a pre-construction notification (PCN) if the proposed activity would impact more than 1/10-acre. This change may reduce permitting time for in-stream retrofits or passage improvements required by state or federal agencies (e.g., Endangered Species Act compliance).
• Rescind NWP 56 (Finfish Mariculture Activities) and Partially Rescind NWP 48 (Commercial Shellfish Mariculture Activities): In response to litigation in Don’t Cage Our Oceans v. U.S. Army Corps of Engineers, the Corps is proposing not to reissue NWP 56. The outcome of that case and the Corps’ proposed change requires standard (individual) permits for finfish mariculture facilities. Also, NWP 48, which authorizes commercial shellfish mariculture activities, would be revised to exclude its use in Washington State as a result of federal court decisions in The Coalition to Protect Puget Sound v. U.S. Army Corps of Engineers, vacating the permit’s application in Washington State. These changes underscore the risks of recent litigation challenges brought by local environmental organizations related to the issuance and use of general permits.

NWPs with Significant Revisions

• NWP 24 (State Programs): NWP 24 has been revised to remove Florida from the list of states with assumed Section 404 permitting authority under the Clean Water Act, following a court decision that vacated the U.S. Environmental Protection Agency’s (EPA) approval of Florida’s program. Activities in Florida that previously fell under state administration now require Corps authorization.
• NWP 27 (Aquatic Ecosystem Restoration, Enhancement, and Establishment): Proposed revisions to NWP 27 include changing its title — and focus — from “habitat” to “ecosystem” restoration, intended to more accurately capture a focus on enhancing ecological functions and services. The rule broadens the definition of acceptable ecological references to include cultural ecosystems and indigenous or local ecological knowledge. It also removes the previous prohibition on converting streams or wetlands to other aquatic types, allowing for more dynamic, process-based restoration approaches. However, the permit still excludes stream channelization. A report will now be required for all activities under NWP 27 (regardless of preconstruction notification).
• NWP 43 (Stormwater Facilities): The Corps proposes to expand NWP 43 to explicitly include a wider range of nature-based stormwater best management practices (BMPs), such as rain gardens, bioretention systems, and regenerative stormwater conveyances. A similar change is proposed to NWP 13 allowing for permissive use of habitat integrated bank stabilization.
• Utility line NWPs (including NWPs 12, 52, 55, 57, and 58): These revisions recommend — but do not require — that project proponents submit as-built drawings to NOAA’s National Ocean Service for inclusion on nautical charts, particularly where authorized structures may affect navigable waters.

Key Revisions to General Conditions

• GC 11 (Equipment and Matting): The revisions would require areas affected by the use of mats to be restored, including the restoration of pre-construction elevations and addressing soil decompaction and revegetation. This change is highly relevant for access roads, laydown yards, and trenching corridors in remote or soft-soil areas and could increase post-construction costs.
• GC 25 (Water Quality): The Corps is proposing a clarification to specify that Section 401 water quality certification is required only for a “proposed activity which may result in any discharge from a point source into waters of the United States.” The Corps states that this revision is intended to align the NWP program more closely with the EPA’s current interpretation of Section 401 under the Clean Water Act, and to reduce uncertainty around activities that trigger the certification requirement.
• GC 28 (Use of Multiple NWPs): The revised language would explicitly prohibit combining acreage limits across multiple NWPs. For example, limits provided under separate NWPs may not be stacked to authorize a greater total impact.

Next Steps for Stakeholders

Businesses should assess the full impact of the proposed changes and determine whether to submit comments to the agency. Among other topics, the Corps is actively soliciting comments on several legal and policy issues, including:

• Clarification on NWP 23: Whether NWP 23 (typically used for activities with minimal environmental impact that have been previously approved by another federal agency) should be documented via a Regulatory Guidance Letter (RGL) or published in the Federal Register. This provides an opportunity to comment on streamlining Corps processes and increasing the availability and transparency of information for regulated parties.
• Use of Baseline Mapping in NWP 27: Consideration of whether baseline mapping used for identifying aquatic resources can substitute for on-site delineations under NWP 27 (Aquatic Habitat Restoration, Establishment, and Enhancement Activities), and the potential impact on permit accuracy and review efficiency.
• PCN/Reporting Structures and ESA/NEPA Compliance: Evaluation of whether the PCN and reporting structures under the new NWP framework adequately support compliance with the Endangered Species Act (ESA) and National Environmental Policy Act (NEPA), particularly in terms of early consultation and impact assessment.
• Policy Consistency on Mitigation and Costs: Ensuring consistency in mitigation policy and associated costs, particularly regarding streambed losses, where there may be regional variability in expectations and enforcement that affects both applicants and aquatic resource protection goals.

Interested parties have until July 18, 2025 to submit feedback to the Corps as provided in the Notice. The Federal Register docket number is COE-2025-0002 and RIN 0710-AB56.

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