Defense Primer: Department of Defense Pre-Positioned Materiel

As part of its global posture, the Department of Defense (DOD) maintains stocks of mission-essential equipment, supplies, and munitions deemed sufficient to attain and sustain strategic objectives in contingency plans. To facilitate rapid deployment of U.S. forces during the initial phases of operations, some of this materiel is pre-positioned at or near points of planned use in specialized facilities (i.e., ashore) and dedicated ships (i.e., afloat).

Why does DOD pre-position materiel?

Pre-positioned war reserve materiel (PWRM) reduces demand for strategic airlift and sealift assets by locating heavy and bulky materiel closer to the theater of operations. It sustains warfighters while supply lines are established and the industrial base surges production. PWRM may also be used to signal U.S. intentions. Materiel stored overseas may demonstrate commitment to allies and partners or enhance the deterrence of potential adversaries. As stated in the Army Operations Field Manual (FM 3-0), a robust PWRM inventory is essential to providing credible support to partner forces during a crisis. Accordingly, enhanced pre- positioning of equipment, munitions, fuel, and materiel is a core focus of both the European Deterrence Initiative (EDI) and Pacific Deterrence Initiative (PDI). During Operation Desert Shield in 1990-1991, PWRM enabled the delivery of Marine Corps armored units to the Persian Gulf one month before the arrival of other armored units shipped from the United States, according to the Congressional Budget Office. In 2022, DOD PWRM equipped U.S. forces supporting the NATO Response Force following Russia’s invasion of Ukraine. The effectiveness of large PWRM stocks, however, also makes them potential priority targets for adversary long- range weapons in conflict scenarios. Responding to such challenges, DOD’s Joint Concept for Logistics envisions a “comprehensive array” of large and small PWRM stocks that can be selectively accessed and quickly shifted between theaters of operations, even in contested environments. In 2023, DOD officials began referencing the incorporation of prepositioned stocks into a “Global Positioning Network” to enable persistent campaigning in the Indo-Pacific.

Responsibilities and Management

The Under Secretary of Defense for Acquisition and Sustainment establishes and maintains a DOD-wide strategic policy for WRM and PWRM. Combatant Commanders (CCDRs) determine PWRM operational requirements in accordance with strategic guidance; the Joint Staff then reviews and validates these requirements. Each military service (hereinafter “service”) maintains and administers PWRM to satisfy such requirements and meet the needs of CCDRs. The services rely upon the Defense

Logistics Agency and contractor support to maintain PWRM, but may seek host nation support for some items. Several sections of Title 10, U.S. Code (U.S.C.) govern PWRM, including the following: • 10 U.S.C. §2229. Requires the Secretary of Defense to

maintain a strategic policy on pre-positioned materiel and to certify annually that current PWRM “meet all operations plans, in both fill and readiness.”

• 10 U.S.C. §2390. Authorizes sale of PWRM to non-

DOD entities during declared international crisis. Requires prompt replenishment of stocks.

• 10 U.S.C. §118b. The FY2021 National Defense

Authorization Act, as amended, requires DOD to submit a classified report to Congress following publication of a new National Defense Strategy detailing PWRM requirements 5, 10, and 25 years into the future.

Funding

As with many other military functions for which DOD is both a customer and key supplier, successful management of DOD pre-positioned materiel involves both appropriated funds from Congress and defense working capital funds that purchase and manage inventories to stabilize item supplies and prices. Two defense appropriations primarily fund PWRM: Operations and Maintenance (O&M) and Procurement. Services use O&M funds for both the pre-positioned materiel itself and the necessary expenses required to operate humidity-controlled ashore facilities and ships carrying afloat assets throughout the year. O&M PWRM requirements are categorized as either mobilization or operating forces requirements in DOD budget justifications. Procurement budgets integrate PWRM requirements within agency-wide requirements for a given weapon system. For example, upgrades to a combat vehicle may include procurements sufficient for “one Army Prepositioned Stock [APS] brigade” along with four (non-PWRM) Armor Brigade Combat Teams. EDI and PDI budget exhibits summarize relevant DOD PWRM activities. For FY2025, DOD requested $713 million for enhanced prepositioning for EDI.

Selected PWRM Programs

Army Pre-Positioned Stocks (APS) The Army considers APS materiel “a cornerstone of the Army’s ability to rapidly project power.” Army Materiel Command (AMC) manages APS, while Army Sustainment Command and other AMC subordinate commands maintain the stocks through regional Army Field Support Brigades and Battalions (see Figure 1). APS contain several categories of materiel:

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• Unit Equipment Sets contain combat equipment and

supplies to support the Army’s force projection strategy. Unit sets mirror Army force structure unit equipment (i.e., brigade combat team or sustainment brigade equipment sets).

• Operational Project Stocks (OPROJ) contain

equipment above normal allowances to provide strategic capabilities essential to the Army’s strategic deployment strategy.

• Army War Reserve Sustainment Stocks contain

materiel (including vehicles and equipment) to sustain military operations by replacing combat losses and consumed supplies.

APS also includes War Reserve Stocks for Allies (WRSA)—which are stocks owned and funded by the United States to be released to supported allied forces under the Foreign Assistance Act (22 U.S.C. §2331h). DOD calculates WRSA requirements alongside PWRM requirements in joint scenario planning.

U.S. Navy and Marine Corps Pre-Positioning The Navy and Marine Corps rely on the afloat Maritime Prepositioning Force (MPF) and ashore Marine Corps Prepositioning Program-Norway (MCPP-N) to expedite deployment of Marine Air-Ground Task Forces (MAGTFs). The Marines’ Blount Island Command, a subordinate of Marine Corps Logistics Command, maintains the MPF and MCPP-N. The MPF consists of two Maritime Prepositioning Ship Squadrons (MPSRONs), operated by the Navy’s Military Sealift Command (MSC). Each MPSRON carries unit equipment and 30 days of supply for one brigade-sized MAGTF when combined with an echelon of personnel, light equipment, and combat aircraft. Each squadron is capable of discharging its cargo pierside, ship-to-ship, ship- to-shore, or by air. MCPP-N consists of ground equipment, munitions, and aviation support equipment to supply a Marine Expeditionary Brigade for 30 days. The Marine Corps’ FY2025 budget request reported plans for additional pre-positioning sites in the Indo-Pacific.

Key U.S. Air Force PWRM The Air Force’s PWRM is managed by Air Force Materiel Command and consists of dispersed ashore and afloat assets containing equipment and resources deemed necessary to initiate expeditionary operations. Afloat stocks are stored aboard two MSC vessels that are under the tactical control of the relevant geographic CCDR. The Air Force pre- positions consumable items such as food and fuel, and sets of equipment designed to provide expeditionary operational support, fuel support, damage recovery, force protection, and medical capabilities. Air Force PWRM consists of three major categories of materiel: • Common Support Equipment (CSE) sets provide

aerospace ground equipment, vehicles, and munitions support equipment to support initial combat operations.

• Fuels Support Equipment (FSE) sets provide ground

and aircraft fuels support.

• Basic Expeditionary Airfield Resources (BEAR) sets

provide personnel support, infrastructure, and flight line support at forward operating sites.

Figure 1. Selected PWRM Locations and Contents

Source: Created by CRS. MCPP-N and MPSRON information from Joint Publication 4-01, The Defense Transportation System (July 2017). APS and USAF PWRM information from U.S. Army G-4 and U.S. Air Force A-4 respectively.

Considerations for Congress

• PWRM for distributed operations. Recent changes to

service operational concepts and battle doctrine emphasize the need to sustain military operations across wider geographical areas than in previous decades. As a result, CCDRs may require more widely distributed and resilient networks of PWRM assets, both ashore and afloat. Congress may wish to evaluate DOD assessments of long-term PWRM requirements, such as those associated with the National Defense Sustainment and Logistics Review (10 U.S.C. §118b).

• Improved Oversight of PWRM. In 2024, the DOD

Office of the Inspector General (OIG) reported inadequate oversight of maintenance of certain items at APS-5. OIG in 2023 reported maintenance concerns with PWRM designated for Ukraine. Congress may assess maintenance of other PWRM assets, PWRM inventory levels, and replenishment rates in light of total requirements for strategic and contingency plans.

Defense Primer: Department of Defense Pre-Positioned Materiel

https://crsreports.congress.gov | IF11699 · VERSION 8 · UPDATED

Cameron M. Keys, Analyst in Defense Logistics and Resource Management Policy

IF11699

Disclaimer

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