Army Corps of Engineers

On September 8, 2023, the Army Corps and EPA issued a final rule to conform the definition of “waters of the United States” to the 2023 Supreme Court decision in Sackett v. EPA. (88 Fed. Reg. 61964, Sept. 8, 2023) (See Sackett v. EPA in “Litigation” below).

The revised rule removes the “significant nexus standard” (discussed below), and redefines “adjacent” as used in the rule to mean “having a continuous surface connection.”

Biden Administration (2021-2025)

Regulation Conforming Regulatory Definition to Sackett v. EPA

On September 8, 2023, (88 Fed. Reg. 61964, Sept. 8, 2023), the Army Corps and EPA issued a final rule to conform the definition of “waters of the United States” to the 2023 Supreme Court decision in Sackett v. EPA. (See Sackett v. EPA in “Litigation” below).

The revised rule removes the “significant nexus standard” (discussed below), and redefines “adjacent” as used in the rule to mean “having a continuous surface connection.”

Revised Definition of “Waters of the United States”

On January 18, 2023, the Army Corps and EPA issued a final rule revising the regulatory definition of “waters of the United States.” (88 Fed. Reg. 3004, Jan. 18, 2023).

The updated rule provided the following definition for “waters of the United States”: 

• (1) traditional navigable waters, the territorial seas, and interstate waters; 
• (2) impoundments of “waters of the United States”; 
• (3) tributaries to traditional navigable waters, the territorial seas, interstate waters, or impoundments when the tributaries meet either the relatively permanent standard or the significant nexus standard; 
• (4) wetlands:
  • (a) adjacent to navigable waters waters; 
  • (b) adjacent to and with a continuous surface connection to relatively permanent impoundments or to tributaries that meet the relatively permanent standard; and 
  • (c) adjacent to paragraph impoundments or jurisdictional tributaries when the wetlands meet the significant nexus standard (“jurisdictional adjacent wetlands”); and 
• (5) intrastate lakes and ponds, streams, or wetlands not identified in the preceding sections that meet either the relatively permanent standard or the significant nexus standard.

The “relatively permanent standard” means relatively permanent, standing or continuously flowing waters connected to paragraph (a)(1) waters, and waters with a continuous surface connection to such relatively permanent waters or to paragraph (a)(1) waters. The “significant nexus standard” means waters that, either alone or in combination with similarly situated waters in the region, significantly affect the chemical, physical, or biological integrity of traditional navigable waters, the territorial seas, or interstate waters.

This regulation has been challenged in court. (See "Challenges to 2023 Rule" in “Litigation” below).

Executive Order on Protecting Public Health and the Environment and Restoring Science to Tackle the Climate Crisis

On January 20, 2021, President Biden signed Executive Order 13990 (Protecting Public Health and the Environment and Restoring Science to Tackle the Climate Crisis). In response to EO 13990, the Army Corps reviewed the 2020 Navigable Waters Protection Rule, and concluded that many elements of the rule hampered federal efforts to address the impacts of climate change on navigable waters, address environmental justice concerns, and more broadly meet the requirements of the Clean Water Act. (See 88 Fed. Reg. 3004, Jan. 18, 2023)

First Trump Administration (2017-2021)

Navigable Waters Protection Rule

On April 21, 2020, the Army Corps and EPA promulgated a new definition of “waters of the United States” in the “Navigable Waters Protection Rule.” (85 Fed. Reg. 22250, Apr. 21, 2020). This rule limited “waters of the United States” to include only four categories of waters: 

1. territorial seas and traditional navigable waters, 
2. perennial and intermittent tributaries, 
3. certain lakes, ponds, and impoundments, and 
4. wetlands that are adjacent to jurisdictional waters, with a continuous surface connection to them. Adjacent also includes certain “wetlands separated from other jurisdictional waters only by natural berms, banks, or dunes.”

Repeal of Clean Water Rule

On October 22, 2019, the Army Corps and EPA repealed the Obama Administration’s “Clean Water Rule,” and reinstated preexisting regulations. (84 Fed. Reg. 56626, Oct. 22, 2019). The agencies offered a variety of explanations for this repeal, but broadly argued that the Clean Water Rule had expanded agencies’ jurisdiction beyond Constitutional limits and Congressional intent.

Obama Administration (2009-2017)

Clean Water Rule: Definition of “Waters of the United States”

On June 29, 2015, the Army Corps and EPA promulgated the “Waters of the United States” rule, to clarify the definition of “waters of the United States” under the Clean Water Act. (80 Fed. Reg. 37054, June 29, 2015). This rulemaking responded to two Supreme Court decisions, Solid Waste Agency of Northern Cook County v. U.S. Army Corps of Engineers, 531 U.S. 159 (2001) and Rapanos v. United States, 547 U.S. 715 (2006), which each held that the Clean Water Act extended beyond purely navigable waters to waters with a “significant nexus” to navigable waters. 

In response, the Army Corps and EPA promulgated the “Clean Water Rule. The rule provided that “the term ‘waters of the United States’ means:

1. All waters which are currently used, were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide;
2. All interstate waters, including interstate wetlands;
3. The territorial seas;
4. All impoundments of waters otherwise identified as waters of the United States under this section;
5. All tributaries [of the preceding waters]
6. All waters adjacent to a water identified in [the preceding section], including wetlands, ponds, lakes, oxbows, impoundments, and similar waters;” and
7. A set of identified other water types which become jurisdictional only if a case-specific analysis reveals the requisite “significant nexus.”

The term “significant nexus” was defined to mean “that a water, including wetlands, either alone or in combination with other similarly situated waters in the region, significantly affects the chemical, physical, or biological integrity” of jurisdictional waters.

Litigation

Sackett v. EPA

In Sackett v. EPA, landowners who had engaged in construction near a lake challenged the Army Corps’ determination that their construction required a permit, because it involved dredging and filling an area of wetlands near navigable waters. The majority of the Court held that, to qualify as “waters of the United States” under the Clean Water Act, a wetland “must be indistinguishably part of a body of water that itself constitutes ‘waters’ under the [Clean Water Act].” Sackett v. Env't Prot. Agency, 598 U.S. 651, 676 (2023). The majority in Sackett held that the “waters of the United States” definition “extends to only those wetlands with a continuous surface connection to bodies that are ‘waters of the United States’ in their own right, so that they are indistinguishable from those waters.” Id. at 684 (internal quotations omitted).

Challenges to 2023 Rule - West Virginia v. EPA and Kentucky v. EPA

The final rule published in January 2023 was challenged in multiple courts. In West Virginia v. EPA, No. 23-cv-32 (D.N.D. filed 2023) the court granted the plaintiffs’ motion for a preliminary injunction, and the appeal was dismissed in West Virginia v. EPA, No. 23-2411 (8th Cir. filed 2023). In Kentucky v. EPA, No. 23-5345 (6th Cir. filed 2023), the litigation was stayed while the Supreme Court decided Sackett v. EPA. Since the Sackett decision came down, litigation has been ongoing. Most recently, EPA filed its appellee brief in February 2024.

On December 19, 2024, the Army Corps of Engineers issued a final rule establishing the Corps' ASPs to implement the PR&G. (89 Fed. Reg. 103992, Dec. 19, 2024) The ASPs provide a framework for the Corps to use in the planning process for projects, plans, and programs. Climate change is to be considered in much of the Corps’ planning processes. 

The final rule requires the Army Corps of Engineers to consider a wide range of climate change-related issues in assessing federal investments in water resources. For example, the Corps must identify and account for climate change, and its accompanying uncertainties, “in all stages of the planning process.” “Analysis of climate change impacts shall reflect the best available actionable science,” and must consider “impacts such as inland and coastal climate change impacts on flood and drought hazards using the most up-to-date science, policies, and tools available.” In addition, the final rule requires the Corps to “ensure climate resilience and adaptation are incorporated and considered throughout the planning process and across alternatives.” (33 C.F.R. § 234.7(f))

Biden Administration (2021-2025)

Specific Procedures To Implement the Principles, Requirements, and Guidelines for Federal Investments in Water Resources

On December 19, 2024, the Army Corps of Engineers issued a final rule establishing the Corps' ASPs to implement the PR&G. (89 Fed. Reg. 103992, Dec. 19, 2024) The ASPs provide a framework for the Corps to use in the planning process for projects, plans, and programs. Climate change is to be considered in much of the Corps’ planning processes. 

The final rule requires the Army Corps of Engineers to consider a wide range of climate change-related issues in assessing federal investments in water resources. For example, the Corps must identify and account for climate change, and its accompanying uncertainties, “in all stages of the planning process.” “Analysis of climate change impacts shall reflect the best available actionable science,” and must consider “impacts such as inland and coastal climate change impacts on flood and drought hazards using the most up-to-date science, policies, and tools available.” In addition, the final rule requires the Corps to “ensure climate resilience and adaptation are incorporated and considered throughout the planning process and across alternatives.” (33 C.F.R. § 234.7(f))

• Corrections to Final Rule (90 Fed. Reg. 3035, Jan. 14, 2025)
• Final Rule (89 Fed. Reg. 103992, Dec. 19, 2024)
• Proposed Rule (89 Fed. Reg. 12066, Feb. 15, 2024)

First Trump Administration (2017-2021)

N/A.