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Coast Guard: Improved Reporting on Domestic Icebreaking Performance Could Clarify Resource Needs and Tradeoffs

GAO-24-106619 Published: Jan 16, 2024. Publicly Released: Jan 16, 2024.
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Fast Facts

The U.S. Coast Guard uses icebreaking vessels to keep waterways open and safe for commercial ships during winter in certain domestic areas, including the Great Lakes.

This Q&A report looks at the economic impact of ice in the Great Lakes and the Coast Guard's assessment of what it needs to continue keeping waterways open. The Coast Guard is currently able to break ice with its vessels but identified an aging fleet as a risk for future efforts.

The Coast Guard provides Congress with information about its icebreaking efforts, but the reports lack data that could better communicate the resources it needs.

Our recommendation addresses this issue.

A heavy icebreaker vessel used in the Great Lakes

An image of a U.S. Coast Guard icebreaking vessel in the Great Lakes.

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What GAO Found

Great Lakes vessel-based commerce declines during the winter, primarily due to lock closures and weather conditions. GAO found, by conducting a regression analysis, that the amount of ice coverage on the Great Lakes was generally not associated with selected economic indicators, such as regional unemployment rates and unfilled orders for iron and steel production. Some industry stakeholders told GAO they take steps in their operational planning to mitigate the effects of delays due to ice. For example, two Great Lakes steel producers said they stockpile several months of iron ore inventory as the ice season begins.

The Coast Guard operates a fleet of 33 vessels comprised of heavy, medium, and light domestic icebreakers as well as two types of ice-capable buoy tender vessels to conduct its domestic icebreaking mission. The Coast Guard generally meets its domestic icebreaking goals using available vessels; however, it identified challenges with its aging fleet and the need for additional heavy and medium capabilities as risks to its ability to conduct its icebreaking mission in the future. To address these risks, the Coast Guard determined that it would need more than $3 billion to recapitalize its medium and light domestic icebreaking fleet and procure a second heavy icebreaker, plus funds for related port infrastructure.

The Coast Guard reports some information on its domestic icebreaking performance, but it collects additional information it could use to improve the transparency of its icebreaking performance and articulate resource needs and tradeoffs. For example, the Coast Guard projects its future mission needs by conducting a fleet mix analysis to determine the type and number of assets needed to meet forecasted demands. However, this analysis does not reflect the full scope of the assets required to fulfill the mission, as it excludes the ice-capable buoy tenders that serve as a stop-gap for the aging icebreaking vessels when they are not available due to maintenance. By more transparently communicating its performance, including the actual extent of vessel utilization and resource-based prioritization, the Coast Guard could provide stakeholders with better information on operational gaps, risks, as well as resource needs and tradeoffs.

The James M. Inhofe National Defense Authorization Act (NDAA) for Fiscal Year 2023 introduces proposed domestic icebreaking performance standards for the Coast Guard specific to the Great Lakes. According to Coast Guard officials, the proposed standards will not change how the Coast Guard conducts its icebreaking operations, but could lead to improved data collection and performance reporting. However, new data collection requirements could increase operating costs as both the Coast Guard and industry may need additional equipment or procedures to collect new or more detailed data.

Why GAO Did This Study

The U.S. Coast Guard operates and maintains icebreaking vessels to promote safety in U.S. waters, along with its other missions. The Coast Guard breaks ice to help keep channels and harbors open to navigation to facilitate "the reasonable demands of commerce." This assistance includes establishing and maintaining open tracks in critical waterways, assisting and escorting vessels stuck in ice, and removing hazards created by ice. In 2020, industries shipped over 100 million tons of iron ore, limestone, coal, and other commodities through the Great Lakes. Some industry stakeholders who rely on shipping channels in the Great Lakes raised concerns that the Coast Guard does not have adequate resources available to facilitate the reasonable demands of commerce.

The NDAA for Fiscal Year 2023 includes a provision for GAO to review Coast Guard icebreaking operations in the Great Lakes. This report describes the economic impacts of ice coverage on the Great Lakes by examining associations between ice coverage and effects on certain economic indicators; the Coast Guard's determinations of its icebreaking resource needs; and the potential effects of the proposed standards on the Coast Guard's icebreaking efforts.

To conduct this work, GAO reviewed relevant laws and Coast Guard policies, guidance, and analyses. GAO conducted regression analyses to examine the relationship between the average monthly Great Lakes ice coverage using data from the U.S. National Oceanic and Atmospheric Administration and a variety of relevant regional and industry-specific economic indicators. GAO also interviewed Coast Guard officials to understand domestic icebreaking operations and priorities, as well as industry stakeholders who operate or rely on the Great Lakes.


GAO is recommending that the Coast Guard, using data it already collects, report more complete performance information to Congress on its domestic icebreaking operations to better articulate resource needs and tradeoffs.

Recommendations for Executive Action

Agency Affected Recommendation Status
United States Coast Guard The Commandant of the Coast Guard should, using data the Coast Guard already collects, report more complete performance information to Congress on its domestic icebreaking operations to better articulate resource needs and tradeoffs. (Recommendation 1)
The Coast Guard concurred with this recommendation and noted in December 2023 that it intends to update its current performance measures and formalize new ones, as applicable, using data it already collects. In June 2024, the Coast Guard stated that its initial data collection efforts for the 2023-2024 ice season were completed but light winter and ice conditions prevented full evaluation of the new efforts. The Coast Guard plans to issue a report with the proposed performance measures in August 2024 and the proposed performance measures will be implemented and evaluated for the 2024-2025 ice season. The Coast Guard plans to codify the results through an update of the Commandant Instruction 16151.1D. by June 30, 2025. We will continue to monitor the Coast Guard's efforts as it develops, evaluates, and codifies its new domestic icebreaking performance measures.

Full Report

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CommerceData collectionDefense budgetsEconomic indicatorsHarborsHomeland securityIcebreakersInland waterwaysInternal controlsLakesMilitary vesselsPerformance measurementProgram transparencyWaterways