Contents

• Introduction
• Overview of USACE Supplemental Appropriations
• Funded Activities
• Emergency Action and Repairs
• Construction to Support Recovery and Mitigation
• Varied Purposes
• Legislative Direction
• Eligible Activities
• Differences from Annual Appropriations
• Statutory and Policy Exemptions
• Subsequent Acts Providing Further Direction
• USACE Implementation
• Project Selection
• Implementation Guidance
• Spend Plans
• Reporting

Summary

Congress has passed supplemental appropriations to fund the U.S. Army Corps of Engineers (USACE) in the Department of Defense to carry out authorized emergency disaster-related activities, to construct flood risk reduction projects to mitigate future disasters, to invest in civil works infrastructure, and for other purposes. From FY1990 to FY2025, Congress provided approximately $100.9 billion to USACE in FY2024 dollars. These appropriations were in addition to annual regular appropriations to USACE for its civil works responsibilities, which consist largely of developing and maintaining navigable waterways, flood and storm risk reduction projects, and aquatic ecosystem restoration. In some fiscal years, supplemental appropriations amounts for USACE approached or exceeded the levels of annual appropriations. For example, from FY2016 to FY2025, Congress provided supplemental appropriations of $53.3 billion to USACE, compared with annual appropriations of $83.6 billion (all in FY2024 dollars). Supplemental appropriations deliberations by Congress regularly involve funding for USACE civil works accounts. Congressional approaches at appropriating funds in past supplementals have varied and may inform how Congress chooses to approach future supplementals.

Funded Activities

Since the 1940s, Congress has authorized USACE to perform emergency flood fighting activities (e.g., sandbagging, temporary levee construction) and to repair certain nonfederal flood control works damaged by floods. Congress appropriates funds to the agency's Flood Control and Coastal Emergencies account for these activities. Congress also appropriates funds to the Operation and Maintenance account for post-flood repairs of USACE-operated projects. Congress typically funds both accounts in regular appropriations but often has supported these accounts with supplemental funding. As part of post-disaster recovery efforts since the mid-2000s, Congress also has provided USACE with supplemental appropriations to study and construct flood control projects through the Investigations, Construction, and Mississippi River and Tributaries accounts. Supplemental appropriations enacted in response to flooding events since FY2013 often have directed that USACE supplemental funds be used to study and construct new or ongoing USACE flood risk reduction projects in states and territories affected by specified disasters or for disasters that occurred during a specified time period. Congress also has provided USACE with supplemental funding unrelated to flood events, such as for investing in infrastructure, promoting economic development, responding to the Coronavirus Disease 2019 pandemic, and assisting drinking water facility infrastructure.

Legislative Direction

Congress generally has tailored supplemental appropriations acts to reflect specific characteristics of recent disasters or economic, infrastructure, or security concerns. Congress generally has prescribed specifications that determine eligibility for projects and activities that may receive supplemental funding provided to USACE accounts. Supplemental appropriations acts often have differed from regular appropriations acts in various ways. For example, in supplemental appropriations acts, Congress often has not limited the initiation of new USACE studies and construction projects. Supplemental appropriations also have included exemptions to requirements and policies that typically apply to USACE studies and projects, such as nonfederal cost-share waivers.

USACE Implementation

For some supplemental appropriations acts, USACE has developed implementation guidance for allocating supplemental funding. Although this information is sometimes not publicly available, USACE recently published implementation guidance for allocating funding for numerous supplemental appropriation acts. For most of these acts, USACE also has published spend plans, often at Congress's direction, identifying studies and projects anticipated to receive the majority of allocated funding. These spend plans typically have included a topline study or project allocation figure and, in some cases, a brief description of the anticipated work. Congress often has required in supplemental appropriations acts monthly reporting from USACE to the House and Senate Appropriations Committees on the allocation, obligation, and expenditure of supplemental funds. These monthly reports typically are not publicly available.

Introduction

The U.S. Army Corps of Engineers (USACE) is a Department of Defense agency with civil works responsibilities; its primary responsibilities include building and operating water resources projects to maintain navigable channels, reduce flood and storm risk, and restore aquatic ecosystems.¹ USACE also undertakes flood fighting and other disaster response activities.² Congress has enacted supplemental appropriations to fund authorized disaster-related activities. In addition, Congress has provided supplemental appropriations to USACE to invest in infrastructure and economic development, respond to the Coronavirus Disease 2019 pandemic, and provide assistance to drinking water facilities. These appropriations are in addition to regular annual appropriations provided in Energy and Water Development Acts.³

This report provides an overview of USACE supplemental appropriations and discusses how Congress has directed and USACE has implemented such funding in the past.⁴ In the future, Congress may adopt or borrow aspects from these approaches, or Congress could break from the funding and direction provided by supplemental appropriations acts described in this report.

Overview of USACE Supplemental Appropriations

From FY1990 to FY2025, Congress provided approximately $81.2 billion in nominal dollars ($100.9 billion in FY2024 dollars; Figure 1; Table A-1) to USACE through supplemental appropriations acts. Of this total, Congress provided $47.6 billion in nominal dollars ($53.3 billion in FY2024 dollars) in the last 10 fiscal years (i.e., FY2016 through FY2025). This figure compares to the agency's regular (i.e., non-supplemental) annual appropriations of approximately $75.3 billion in nominal dollars ($83.6 billion in FY2024 dollars) over that period. Table 1 lists supplemental appropriations acts from FY2013 through FY2025 that provided funding to USACE and the appropriations amounts (in nominal dollars) provided to USACE budget accounts.

Figure 1. USACE Supplemental Funds: FY1990-FY2025 (in billions of constant FY2024 dollars)

Source: Congressional Research Service, using appropriations acts providing U.S. Army Corps of Engineers (USACE) supplemental funding. Amounts adjusted to FY2024 dollars using U.S. Bureau of Economic Analysis, "Table 3.9.4. Price Indexes for Government Consumption Expenditures and Gross Investment," accessed April 2025. FY2025 figures are not adjusted. Notes: Fiscal year represents the first fiscal year for which the supplemental appropriations were provided. (Some acts provide advance appropriations, meaning the appropriations are first available in future fiscal years.) Amounts do not include rescissions, transfers, or other reductions. Supplemental funding labeled as natural disaster-related is based on the respective act specifying that the funding is in response to natural disasters or is to support activities such as emergency situations, repair of projects impacted by natural disasters, and development of flood control projects. Supplemental funding for other purposes is labeled as other.

Funded Activities

Emergency Action and Repairs

Since the 1940s, Congress has authorized USACE to perform emergency flood fighting activities (e.g., sandbagging, temporary levee construction) and to repair certain nonfederal flood control works damaged by floods.⁵ Congress funds these activities through the agency's Flood Control and Coastal Emergencies (FCCE) account.⁶ Annual appropriations for this account can be depleted in fiscal years with increased disaster work demand. Congress often has replenished funding for the FCCE account by subsequently enacting supplemental appropriations. Congress also directs appropriations for post-flood repairs of USACE-operated projects through the Operation and Maintenance (O&M) account, which it may support with supplemental funding in addition to providing regular appropriations.⁷

Construction to Support Recovery and Mitigation

As part of post-disaster recovery efforts since the mid-2000s, Congress has provided USACE with supplemental appropriations to study and construct flood control projects through the Investigations, Construction, and Mississippi River and Tributaries (MR&T) accounts.⁸ (For more information on USACE accounts for which Congress regularly has provided supplemental appropriations, see Appendix B.) Supplemental appropriations provided in response to flooding events from FY2013 and after often have directed that most or some of USACE supplemental funds be used to study and construct new or ongoing USACE flood risk reduction projects in states and territories affected by specified disasters or for disasters from a specified period. For example, the Bipartisan Budget Act of 2018 (BBA 2018; P.L. 115-123) provided $17.4 billion in supplemental appropriations; of this total, $135 million was provided to the Investigations account for flood and storm damage reduction studies, and $15.0 billion went to the Construction account and $400 million to the MR&T account to construct flood and storm damage reduction projects.⁹

Varied Purposes

Congress also has provided USACE with funding unrelated to flood events. Congress provided the agency with $4.6 billion as part of the American Recovery and Reinvestment Act of 2009 (ARRA; P.L. 111-5) and $17.1 billion as part of the Infrastructure Investment and Jobs Act (IIJA; P.L. 117-58). These acts included appropriations for other USACE accounts beyond those previously mentioned, such as the Regulatory Program and Expenses accounts. The Coronavirus Aid, Relief, and Economic Security Act (P.L. 116-136) provided funds for USACE coronavirus prevention and response, and the Continuing Appropriations and Ukraine Supplemental Appropriations Act, 2023 (P.L. 117-180), designated USACE Construction funds for environmental infrastructure assistance, which went to the 2022 Jackson, MS, water crisis response.¹⁰ Although the Disaster Relief Supplemental Appropriations Act, 2023 (Division N, Title IV, of P.L. 117-328), provided supplemental appropriations to USACE budget accounts to address flood impacts and mitigation, the act also provided Construction and O&M supplemental funding for USACE to allocate in its work plans to authorized projects regardless of flood impacts.¹¹

Legislative Direction

Eligible Activities

Congress generally has tailored supplemental appropriations acts to reflect specific characteristics of recent disasters or economic, infrastructure, or security concerns. At times, Congress has specified in law certain projects to receive funding.¹² Starting in the 111^th Congress, supplemental appropriations acts have not identified specific studies and projects to receive such funding; instead, Congress has prescribed eligibility specifications for projects and activities to receive supplemental funding provided to USACE accounts. For example, supplemental funding may apply to USACE activities and projects of a specific type (e.g., flood and storm risk reduction, navigation dredging), affected by or in response to certain events (e.g., natural disasters, coronavirus), and/or in certain localities (e.g., states with multiple major disasters in certain fiscal years).

Differences from Annual Appropriations

Enacted appropriations language directing supplemental appropriations acts for USACE has, in many cases, differed from language in regular appropriations acts. As mentioned, supplemental appropriations acts since the 111^th Congress have not specified individual studies and projects to receive funding, whereas annual appropriations to USACE have included directed funding for studies and projects in explanatory statements.¹³ In supplemental appropriations acts that have provided USACE Investigations, Construction, and MR&T account funding, Congress often has not limited the initiation of new USACE studies and construction projects; by contrast, annual appropriations for USACE generally limit new study and construction starts. Frequently, supplemental appropriations acts have designated funding in USACE accounts as an emergency requirement, effectively exempting these appropriations from enforcement under applicable budgetary rules that typically are applied to regular annual appropriations.¹⁴

Statutory and Policy Exemptions

Supplemental appropriations also have included exemptions to statutory requirements and policies that typically apply to USACE studies and projects. These exemptions have included waiving requirements that limit USACE's ability to proceed with projects that exceed their authorization of appropriations and waiving nonfederal cost sharing.¹⁵ In some supplemental appropriations acts, Congress has allowed USACE to proceed from a feasibility study for a project to construction with approval of the Assistant Secretary of the Army for Civil Works (ASACW) rather than requiring project-specific congressional construction authorization. Some supplemental appropriations acts also have required the studies and projects to be completed with the supplemental funding provided in order to apply exemptions. Table 2 summarizes the approach to various statutory requirements and policies in selected recent supplemental appropriations acts.

Subsequent Acts Providing Further Direction

Some appropriations acts have included provisions related to studies and projects retaining or taking on the terms and conditions of previous supplemental funding. For instance, Title IV of the Disaster Relief Supplemental Appropriations Act, 2025 (Division B of P.L. 118-158), provided Construction funding for projects that were previously funded with certain supplemental appropriations acts.¹⁶ The act directed that the additional funding have the same terms and conditions as provided by the supplemental appropriations that previously funded the project. The BBA 2018 directed USACE to transfer $279 million of unobligated FCCE and O&M funding from Title I of the Disaster Relief Appropriations Act, 2013 (Division A of P.L. 113-2), to the Construction account to rehabilitate, repair, and construct USACE projects related to consequences of Hurricane Sandy. In another instance, Title I of the Energy and Water Development and Related Agencies Appropriations Act, 2024 (Division D of P.L. 118-42), directed the use of $1.4 billion from unobligated and unallocated prior-year IIJA Construction appropriations to fund projects listed in the explanatory statement and specified that projects receiving these IIJA funds would be subject to the terms and conditions of IIJA funding. The act also included more provisions regarding the treatment of studies and projects in relation to supplemental appropriations (see text box, "Legislative Direction in the Energy and Water Development and Related Agencies Appropriations Act, 2024").

USACE Implementation

Project Selection

After the enactment of supplemental appropriations, USACE has selected studies and projects that qualify based on the law to receive the funding. Some supplemental appropriations acts have specified that studies and projects in certain states and territories, such as those recently impacted by disasters, are eligible to receive funding. In those cases, eligibility has not guaranteed funding for studies and projects in those locations; for example, for BBA 2018 Construction appropriations, USACE funded projects in 14 of the 33 qualifying states and one of the three qualifying territories.¹⁷ Congress sometimes has stipulated what projects to prioritize for allocations. For example, Congress directed in the IIJA for the ASACW to prioritize for Construction funding projects that directly benefit economically disadvantaged communities and inland waterway projects included in USACE's Capital Investment Strategy.¹⁸

To determine which projects to fund, USACE has scored and ranked work packages of eligible construction projects to compile a list of proposed allocations.¹⁹ USACE has stated that eligibility for projects to receive supplemental appropriations has been narrow and targeted for some acts, and selection did not require extensive ranking among the finite and limited projects eligible for funding.²⁰

Implementation Guidance

For some laws, USACE has developed implementation guidance for allocating supplemental funding. Although publicly available information has varied, USACE published implementation guidance for numerous acts providing supplemental funding to USACE, most recently including P.L. 115-123, P.L. 116-20, P.L. 117-43, P.L. 117-58, and P.L. 117-328.²¹ Prior to the BBA 2018, USACE did not publish implementation guidance; however, after enactment of ARRA in 2009, President Obama issued a presidential memorandum directing agencies to develop transparent, merit-based selection criteria to guide their discretion in committing, obligating, or expending funds under the law.²² USACE subsequently published an agency-wide Recovery Act Plan.²³

Spend Plans

For most of the acts providing USACE with supplemental appropriations since FY2018, USACE has published spend plans identifying studies and projects anticipated to receive the majority of the funding.²⁴ Often Congress has directed USACE to develop and deliver spend plans to the Appropriations Committees by a specified number of days after enactment. In some instances, USACE has published spend plans for short-term repair work separately from long-term work.

Spend plans generally have not provided detailed information on how funding will be used for project activities. For instance, usually spend plans have included a topline study or project allocation figure and possibly a brief description of the anticipated work. USACE also has designated a portion of supplemental funding from some acts as part of a risk management and future investment reserve.²⁵ Some spend plans have included expected obligations of funding over several fiscal years. For instance, USACE's initial list of ARRA-funded projects included approximately 830 ARRA projects with projected expenditures out to FY2011,²⁶ and spend plans for Investigations and Construction funding from the Disaster Relief Supplemental Appropriations Act, 2025, provide estimated obligations through FY2027 for some activities.²⁷ USACE also has released amendments to some of its spend plans, which have reflected changes such as cancelation of projects, reprogramming of funds, updates of anticipated obligations, and adjustments in scope of work for a project.²⁸

Reporting

Congress has directed USACE to regularly provide it with reports detailing estimates of damages to USACE projects and funds expended for repairs of nonfederal flood control works.²⁹ Congress often has required in supplemental appropriations acts monthly reporting from USACE to the Appropriations Committees of the House and the Senate on the allocation, obligation, and expenditure of supplemental funds.³⁰ In some acts, Congress has required USACE to provide updates on implementing newly funded activities. For example, the IIJA required USACE to brief the Appropriations Committees on implementation of a newly authorized pilot program for flood risk reduction studies in economically disadvantaged communities,³¹ and Title I of the Disaster Relief Appropriations Act, 2013 (Division A of P.L. 113-2), directed USACE to report on progress and the results of a comprehensive study to address the flood risk areas impacted by Hurricane Sandy.³² USACE recently launched a geospatial Supplemental Projects Viewer with information on the latest milestone and completion schedule for the majority of projects funded by the BBA 2018; Additional Supplemental Appropriations for Disaster Relief Act, 2019 (P.L. 116-20); IIJA; DRSAA 2022; and DRSAA 2023;³³ however, for these laws and others, USACE has rarely provided publicly available information on the rate of obligation and expenditures of supplemental funding or detailed descriptions of project work.³⁴

Appendix A. Supplemental Appropriations for USACE from FY1990 Through FY2025

From FY1990 to FY2025, Congress provided approximately $81.2 billion in nominal dollars ($100.9 billion in FY2024 dollars) to the U.S. Army Corps of Engineers (USACE) through supplemental appropriations. Table A-1 lists supplemental appropriations acts during this time period that provided funding to USACE and the appropriations, in nominal dollars, provided to USACE budget accounts. Although the majority of funding was for the Flood Control and Coastal Emergencies (FCCE) and Operation and Maintenance (O&M) accounts through FY2007, many subsequent appropriations acts provided the majority of their funding to accounts supporting project study and construction: the Investigations, Construction, and MR&T accounts.

Appendix B. Description of USACE Supplemental Funding for Selected Accounts

The majority of supplemental appropriations generally have provided funding to the following USACE accounts. Below are summaries of these accounts and the types of activities conducted, particularly related to disaster activities, with supplemental funding provided to them.³⁵ The appendix begins with describing the accounts funded by most supplemental appropriations acts, the Flood Control and Coastal Emergencies (FCCE) and Operation and Maintenance (O&M) accounts, and then describes the accounts that have increasingly received funds for activities related to project study and construction.

Flood Control and Coastal Emergencies Account

The FCCE account is the primary account through which the USACE funds disaster-related activities. The primary activities funded under FCCE are flood fighting (e.g., sandbagging), emergency preparedness and response, and repair of damaged nonfederal flood and hurricane protection projects.³⁶ Congress authorized USACE in the Flood Control Act of 1941 (33 U.S.C. §701n) to assist in flood fighting and flood response. USACE can assist in flood fighting at the discretion of its Chief of Engineers to protect life and property, principally when state resources are overwhelmed. Congress also authorized USACE to operate the Rehabilitation and Inspection Program (RIP, also known as the P.L. 84-99 program) to fund the repair of participating nonfederal flood control works (e.g., levees, dams, dunes) damaged by natural events.³⁷ In supplemental appropriations acts, Congress often has directed USACE, using such FCCE funds, to restore the full project profile of coastal storm risk management at full federal expense.³⁸

The FCCE account could receive appropriations in anticipation of natural disasters, but annual discretionary funding for the account for the most part has been for preparedness activities.³⁹ Congress has given the Secretary of the Army (generally delegated to the Assistant Secretary of the Army for Civil Works [ASACW]) discretion to transfer from existing appropriations the monies necessary for the emergency work referenced above, until funds become available in the applicable account through supplemental appropriations or other avenues.⁴⁰ Congress often has specified that FCCE funding, in addition to other USACE supplemental funding, is to be distributed for the highest priority dredging and repairs based on risks and consequences.

Operation and Maintenance Account

The O&M account funds activities related to existing USACE projects that the agency operates and maintains, including upkeep of physical infrastructure and other activities (e.g., dredging of ports and waterways). Common disaster activities funded under this account include repair of damaged federally operated flood and hurricane protection projects (e.g., dams, levees, floodwalls) and dredging of authorized federal navigation channels. Some of these funded activities have been more short term, whereas other O&M funded activities have funded more long-term activities. Sometimes, Congress has directed USACE to fund Harbor Maintenance Trust Fund-eligible activities with Treasury funds instead of through the trust fund.

Investigations Account

The Investigation account provides funds for USACE studies and related activities. Studies include feasibility studies that may lead to recommendation for construction of a new USACE project or to modification of an authorized project. Generally, these studies were authorized in law or by committee resolution.⁴¹ Some supplemental funding for the Investigations account also has supported comprehensive studies and watershed studies, which focused predominantly on flood and storm damage reductions.⁴² Preconstruction, engineering, and design activities for USACE projects prior to construction authorization also have been eligible for some USACE supplemental funding from the Investigations account.

Construction Account

The Construction account generally funds new project construction and major upgrades to existing projects (e.g., significant dam repairs). For example, supplemental Construction funding has been used to improve existing USACE coastal and riverine flood-risk reduction projects and for new USACE construction projects to reduce flood risks in certain geographic locations. Although USACE projects usually must be authorized in order to receive Construction appropriations, some supplemental appropriations acts did not require prior authorization; instead, some acts allowed for authorization of the project after enactment or for ASACW approval of a project that was studied using Investigations funding from the same supplemental appropriations act.⁴³ Some supplemental appropriations acts have specified that a certain amount of Construction funding is to support projects under identified Continuing Authorities Programs.⁴⁴ Supplemental appropriations acts also have provided Construction funds for emergency situations at USACE projects, such as emergency dredging of shoaled material, and to rehabilitate and repair damage caused by natural disasters to USACE projects.

Mississippi River and Tributaries Account

The Mississippi River and Tributaries (MR&T) account supports specific flood control and navigation projects for the lower Mississippi River Valley. Subaccounts include Investigations, Construction, and O&M for such projects. Supplemental expenditures under this account typically have consisted of repairing damaged MR&T levees, floodways, and other project features and addressing emergency situations. For some supplemental appropriations acts, the account also has funded long-term activities similar to those funded by the Investigations and Construction accounts.

Footnotes