Through its ATON mission, the Coast Guard promotes safe waterways and an efficient Marine Transportation System. The Coast Guard has statutory responsibility to operate and maintain a system of maritime aids to facilitate navigation and to prevent disasters, collisions, and wrecks. To fulfill this mission, the Coast Guard operates and maintains ATON that are placed along coasts and navigable waterways as guides to mark safe water and to assist mariners in determining their position in relation to land and hidden dangers. As mentioned earlier, this report focuses on two categories of ATON: fixed ATON that include lighthouses, towers, and other structures that are directly affixed to the ground or seabed; and floating ATON that include buoys and markers anchored to the sea bed by a concrete or metal sinker connected by a metal chain or mooring. See figures 1 and 2 for examples of fixed and floating ATON. The Coast Guard uses several types of vessels to place and service fixed and floating ATON. These ATON vessels include buoy tenders, construction tenders, and boats. As of October 2019, the Coast Guard had a fleet of 79 ATON cutters and 190 ATON boats—which varied in size from a 240-foot Great Lakes Icebreaker to 16-foot ATON boats. (See appendix I for additional details on the Coast Guard’s fleet of ATON vessels.) The Coast Guard’s ATON program consists of several offices and units that work together to carry out the ATON mission: Office of Navigation Systems: Based at Coast Guard headquarters in Washington, D.C., the primary ATON-related roles and responsibilities of Office of Navigation Systems officials include providing oversight and approval for ATON operations and policy. Specifically, the Aids to Navigation and Positioning, Navigation, and Timing Division within the Office of Navigation Systems is responsible for establishing requirements and policy; providing program level guidance; and coordinating processes, platforms, and personnel necessary to establish, maintain, and operate the U.S. ATON system. Office of Civil Engineering: Based at Coast Guard headquarters in Washington, D.C., the primary ATON-related roles and responsibilities of Office of Civil Engineering officials include providing oversight and approval for ATON engineering and logistics policy, including supervision of the Shore Infrastructure Logistics Center. Shore Infrastructure Logistics Center (SILC): Based in Norfolk, VA, SILC supervises the Civil Engineering Units that execute fixed ATON depot-level maintenance and recapitalization projects; as well as the Waterways Operations Product Line. Waterways Operations Product Line (WOPL): A division of the Coast Guard’s Shore Infrastructure Logistics Center, WOPL was established by the Coast Guard in 2016 with the goal of serving as the focal point for implementing engineering and logistics solutions for ATON in order to enhance the mission while reducing costs. To do this, WOPL is to support the ATON mission by providing centralized guidance and oversight covering such issues as ATON acquisition, ATON configuration management (the proper mix of ATON) across the Coast Guard’s nine districts, ATON production and delivery, and ATON logistics and maintenance for the Coast Guard-wide inventory of ATON equipment and systems. WOPL’s support encompasses the entire lifecycle of ATON equipment and systems, from acquisition through disposal. Coast Guard Districts and Sectors: The Coast Guard has nine districts, which have overall responsibility for administration of the ATON within their district. Each district oversees the coordination of operations at the sectors and individual ATON units, which includes cutters, boats, and Aids to Navigation Teams. Figure 3 shows a map of the Coast Guard’s nine districts and the numbers of fixed and floating ATON in each district as of November 2019. The ATON units are responsible for the servicing and maintenance of ATON by conducting both routine servicing based on the last-service dates of the ATON and non-routine servicing of ATON within their area of responsibility. The non-routine servicing process includes responding to and addressing discrepant ATON, which are aids that are not functioning properly due to, for example, a weather-related event such as a hurricane, or an equipment failure. Timely response to and correction of discrepant ATON is a high-priority task for the Coast Guard. According to internal guidance, the Coast Guard has a tiered approach to address ATON discrepancies that accounts for the importance of the ATON relative to the waterway and the nature of the discrepancy. In particular, according to Coast Guard guidance, the servicing unit response ranges from immediately after notification up to 72 hours or as soon thereafter as weather and resources permit. In some cases, the determining factors do not require responding within 72 hours and the servicing unit is to advise the district of future plans to correct the discrepancy. Coast Guard guidance states that during the routine servicing process for floating ATON (buoys), the primary purpose of the ATON units is to check the buoys’ positions, their condition, and ensure the correct operation of the buoys’ signal hardware. As part of this process, the Coast Guard may extract the buoys from the water and bring them onboard an ATON vessel to check the condition of their mooring chain, hull, and lighting equipment. If necessary, the mooring chains are cleaned and repaired and non-functioning lanterns (lights) are replaced. After the planned repairs are made, the buoys are placed back in their assigned position in the water. See figure 4 for an example of the process used by an ATON unit to service a steel buoy. When ATON units conduct routine or non-routine servicing of fixed and floating ATON, they also collect data on the condition of the ATON. These data provide a “snapshot” of the ATON’s condition at the time of servicing and include the aid’s geographic position; the last date that the ATON was serviced; the next-scheduled service date; and other detailed information about the aid, such as an assessment of the physical integrity of the ATON. If warranted, ATON units can initiate action for repair or replacement of ATON if necessary. The information gathered by ATON units during their servicing activities is entered into a Coast Guard database—the Integrated ATON Information System (I-ATONIS)—that is used to track and monitor fixed and floating ATON. A hardcopy record containing detailed information about each aid is subsequently generated from I-ATONIS and stored in local unit files to track and schedule future fixed and floating ATON servicing dates. According to Coast Guard officials, based on the multi-mission nature of its assets and workforce, the Coast Guard does not budget for, request, or receive funding organized by specific missions or program activities. In addition, Coast Guard financial systems are not structured to collect accounting data by specific missions or program activities, and the Coast Guard does not report expenditures by mission. Rather, the ATON mission receives funding through various sources within the Coast Guard’s annual budget. Specific to repairs and recapitalization of fixed ATON, in fiscal year 2018, $300,000 was allocated from Procurement, Construction, and Improvement funding while $10 million was allocated from the Coast Guard’s Operations and Support funds for depot-level ATON maintenance. We previously reported on the Coast Guard’s management and maintenance of its shore infrastructure, which—in addition to fixed and floating ATON—encompasses over 20,000 shore facilities such as piers, docks, boat stations, air facilities, and housing units at more than 2,700 locations. In July 2018, we found that the Coast Guard had not been able to address many shore infrastructure projects, primarily due to lack of funding, longstanding acquisition management challenges, and that previous Coast Guard leadership prioritized the acquisition of new operational assets to replace aging vessels and aircraft over maintaining and repairing shore infrastructure. We recommended, among other things, that the Coast Guard’s annual Capital Investment Plans reflect acquisition trade-off decisions and their effects. The Coast Guard agreed with this recommendation, and estimated implementing actions by March 2020. In February 2019, we found that almost half of the Coast Guard’s shore infrastructure is beyond its service life, and its current backlogs of maintenance projects, as of 2018, will cost at least $2.6 billion to address. We found that the Coast Guard’s process to manage its shore infrastructure recapitalization and deferred maintenance backlogs did not fully meet 6 of 9 leading practices we previously identified for managing public sector maintenance backlogs. We recommended, among other things, that the Coast Guard establish shore infrastructure performance goals, measures, and baselines to track the effectiveness of maintenance and repair investments and provide feedback on progress made; develop and implement a process to routinely align Coast Guard’s shore infrastructure portfolio with mission needs, including by disposing of all unneeded assets; and employ models for its asset lines for predicting the outcome of investments, analyzing trade-offs, and optimizing decisions among competing investments. The Coast Guard agreed with our recommendations and is taking steps to implement them. The condition of fixed and floating ATON Coast Guard-wide declined slightly from fiscal years 2014 through 2018, as determined by the Coast Guard’s key ATON condition metric. In particular, according to data provided by the Coast Guard, the aid availability rate—the percentage of time ATON are functioning correctly—declined from 98.0 percent in fiscal year 2014 to slightly below the Coast Guard’s performance target percentage of 97.5 percent in fiscal years 2017 (97.4 percent) and 2018 (97.1 percent), as shown in figure 5. While the aid availability rate metric indicates that the condition of fixed and floating ATON Coast Guard-wide declined slightly from fiscal year 2014 through fiscal year 2018, other factors—such as the age of many ATON—have contributed to more significant declines in the condition of ATON for some locations. For example, an internal Coast Guard report states that, as of 2018, nearly a quarter (24 percent) of all floating ATON and over half (59 percent) of all fixed ATON are operating past their designed service lives. On a district level, the conditions of fixed and floating ATON differ from one geographical area to the next, and varying weather conditions often have an impact on the physical condition of ATON. For example, the frigid weather conditions of the Great Lakes in certain months frequently erode the condition of both fixed and floating ATON. Coast Guard officials stated that ATON with large steel hulls many times cannot withstand the pressure and weight of ice that can form on them in the winter months. They also stated that the icy waters delay routine servicing trips for personnel to adequately address ATON, which can contribute to the deterioration of the aids. In District 8’s area of responsibility, which includes much of the Gulf of Mexico, Coast Guard officials said that severe storms and hurricanes can adversely impact the condition of fixed and floating ATON and delay servicing trips for safety reasons. Extended periods of exposure to saltwater is another factor that contributes to the degraded condition of ATON in District 8 and elsewhere, as water salinity often corrodes the hulls of steel buoys. In addition to weather, geographic factors can affect the condition of ATON as well. Coast Guard officials in District 1 (headquartered in Boston) stated that the hard, rocky coast in their district makes it difficult to secure fixed ATON structures to the seabed. As a result, this district requires a higher percentage of floating ATON to mark the location of these hazards and these floating ATON are often damaged by the rocks. See figure 6 for examples of the deteriorating condition of some fixed and floating ATON. Our analysis of Coast Guard data shows that the Coast Guard’s overall repair and recapitalization expenditures for fixed and floating ATON increased during fiscal years 2014 through 2018. Specifically, our analysis of Coast Guard data shows that total ATON repair and recapitalization costs increased from about $12 million in fiscal year 2014 to about $20 million in fiscal year 2018. As shown in figure 7, the majority of the costs for fixed ATON were spent on repairs whereas the majority of the costs for floating ATON were spent on recapitalizations. According to Coast Guard documents, data, and officials, the Coast Guard has faced a variety of challenges in managing its fixed and floating ATON. The reported challenges include the availability of ATON vessels, difficulty in conducting routine ATON servicing in a timely manner, and capacity limits at ATON major repair and refurbishment facilities. Our analyses of Coast Guard data on maintenance required of ATON cutters and boats during fiscal years 2014 through 2018 show that ATON cutter and boat availability varied by type and across classes. As described below, our data analyses showed that 10 of the 12 ATON cutter classes consistently met availability targets, whereas 4 of the 7 classes of ATON boats consistently met availability targets. The Coast Guard determines the condition of its ATON cutters and boats using the following measures—planned and unplanned maintenance days, maintenance hours, and achieved material availability rate. Specifically, Planned maintenance days are the number of days that a vessel is not mission capable due to scheduled maintenance. This measure is applicable to cutters. Unplanned maintenance days are the number of days that a vessel is not mission capable due to unforeseen maintenance issues and associated repair efforts. This measure is applicable to cutters. Maintenance hours are the total number of hours that a vessel spent in maintenance, including both planned and unplanned maintenance. This measure is applicable to boats. Achieved material availability rate is calculated based on a vessel’s availability and performance. For cutters, the target availability rate range is between 53 percent and 65 percent. For boats, the target availability rate target is 80 percent. According to our analysis of Coast Guard data, the number of maintenance days for ATON cutters generally decreased during fiscal years 2014 through 2018, as shown in Figure 8. In addition, our analysis shows that the biggest decrease was with planned maintenance days. The Coast Guard has established a target range for the achieved material availability rate for ATON cutters that includes a minimum rate of 53 percent to a maximum rate of 65 percent. According to our analyses of Coast Guard data, the achieved material availability rate for the ATON cutters varied by cutter class during fiscal years 2016 through 2018, with 10 of the 12 cutter classes having met or exceeded the minimum target material availability rate for all 3 years and the remaining 2 ATON cutter classes having met or exceeded the minimum target material availability rate for 2 of the 3 years analyzed. While most of the ATON cutters met Coast Guard availability rate targets during fiscal years 2016 through 2018, officials in 7 of the 9 districts noted that maintaining some older ATON cutters can take longer to repair because of old and obsolete equipment and the lack of available parts, which decreases their availability to conduct missions. Figure 9 shows the achieved material availability rate for ATON cutters for fiscal years 2016 through 2018. According to our analysis of Coast Guard data, we found that the total number of maintenance hours for ATON boats generally decreased during fiscal years 2014 through 2018, although there was an increase from fiscal year 2017 to 2018. Figure 10 shows the total maintenance hours for ATON boats during fiscal years 2014 through 2018. In comparison to ATON cutters, which have a target range for the achieved material availability rate, ATON boats have a material availability threshold of 80 percent. According to our analyses of Coast Guard data, 4 of the 7 classes of ATON boats consistently achieved the 80 percent availability threshold during fiscal years 2014 through 2018. In particular, we found that the four smaller classes of ATON boats—those 16 to 26 feet in length—consistently achieved the 80 percent availability threshold during fiscal years 2014 through 2018, whereas the three larger classes of ATON boats—those 49-feet in length and longer—failed to consistently meet the 80 percent availability threshold during this 5-year period. In addition to the data on achieved material availability rates, Coast Guard officials from 3 of the 9 districts noted they experienced challenges with the availability of ATON boats. Figure 11 shows the achieved material availability rate for seven classes of ATON boats. The Coast Guard has taken positive steps to manage the ATON program, including issuing strategic plans and directions, creating a unit to provide a Coast Guard-wide perspective in managing ATON, and developing various initiatives to improve management of fixed and floating ATON. However, we found that some ATON-related initiatives to be implemented Coast Guard-wide, such as the foam buoy implementation initiative, do not contain certain elements that can provide better assurance that they will be effectively implemented, such as milestones and completion dates, and desired outcomes to be achieved. The Coast Guard has developed strategic plans and directions that provide guidance for addressing challenges faced in managing fixed and floating ATON. In June 2007, the Coast Guard issued the Maritime Short Range Aids to Navigation Strategic Plan to coordinate and standardize a number of ATON mission activities. According a Coast Guard official, at the time this strategic plan was issued, ATON units within the Coast Guard’s nine districts were operating largely independently in terms of planning and conducting ATON missions and activities. The 2007 plan changed this by developing a strategic approach to ATON management and it identified a number of initiatives to improve ATON program management, including reducing ATON lifecycle costs and maintenance needs, increasing efficiency and service intervals, and improving the performance and reliability of fixed and floating ATON. More recently, the Coast Guard issued the Navigation Systems Strategic Voyage Plan for Fiscal Years 2017-2022, which updates and expands on the 2007 strategic plan by identifying priorities that impact ATON program management broadly and the management of fixed and floating ATON in particular. The plan specifically identifies initiatives, including the use of non-steel floating ATON, development of year-round floating ice ATON, increased use of LED lighting, and the increased use of less expensive fixed ATON alternatives in lieu of lighthouses. In addition to the 2007 and 2017 strategic plans, the Coast Guard also issues annual Strategic Planning Directions. These annual directions outline the Coast Guard’s strategic commitments and are the primary mechanism for apportioning resources and providing guidance to field units on initiatives and actions to improve mission operations, including the ATON mission. For example, the Coast Guard has emphasized continuing to leverage electronic ATON technology where appropriate in an effort to reduce seasonal ATON workload, such as in districts with ATON in waters that are subject to freezing during a part of the year. In addition to developing a strategic approach to management of fixed and floating ATON through its strategic plans, the Coast Guard also created a new unit to provide a Coast Guard-wide, centralized perspective in managing fixed and floating ATON engineering and logistics. In particular, in 2016, the Coast Guard created the Waterways Operations Product Line (WOPL) to centrally manage the distribution, repair, and replacement of fixed and floating ATON and parts; as well as to formulate requests for ATON resources and funding. Since its creation, WOPL has coordinated and helped to implement various Coast Guard- wide initiatives to improve the management of fixed and floating ATON. These initiatives include centralized funding for ATON inspection and major repair services, changes in cost limits for floating ATON refurbishments, and expansion of commercial depot-level maintenance contracts to supplement the Coast Guard’s ATON major repair and refurbishment capacity. WOPL has also analyzed and recommended the transition from steel to foam buoys, where appropriate, to increase life cycle cost savings and reduce servicing times. In addition, WOPL has initiated changes to better manage and sustain the duration of floating ATON, including extending time in the water between major refurbishments from 6 to 9 years for some buoys and increasing the allowance for selected steel buoy hull repair weld hours. The Coast Guard has developed and is implementing a variety of initiatives to address specific ATON management challenges that were discussed earlier in this report. These initiatives include the following: Improving the Availability of ATON Cutters and Boats: The Coast Guard has ongoing initiatives to extend the service lives and to recapitalize certain ATON cutters and boats to improve their availability rates. For example, in fiscal year 2019, the Coast Guard continued the major maintenance availability efforts on the 225-foot Seagoing Buoy Tender fleet. In addition, from 2006 to 2016, a portion of the Coast Guard’s ATON fleet (River Tenders, Buoy Tenders, and Construction Tenders) underwent a limited maintenance program to act as a bridging strategy until replacement assets could be acquired. Our 2018 report on Coast Guard acquisitions noted that the designed service life for each of these tenders is 30 years, but as of the time of the report, their average age was 53 years. In 2018, we reported that the Department of Homeland Security approved the Waterways Commerce Cutter Program to replace aging River Tenders, Buoy Tenders, and Construction Tenders. While the acquisitions have been approved, it will likely be years before the new cutters are built and deployed. The Coast Guard has also had an ongoing initiative since 2007 that has recapitalized the boat fleet by 290 boats. Conducting Routine ATON Servicing in a Timely Manner: The Coast Guard has issued guidance to its districts to look for opportunities to reduce the number of ATON that do not significantly increase navigational risk and explore and leverage new technologies, such as the use of electronic ATON, where feasible. Collectively, these efforts should help to ease the servicing burden. In addition, the Coast Guard has also introduced initiatives focused on improving ATON servicing time. For example, officials in one district told us that they require their ATON units to send in monthly reports on ATON servicing due dates and plans. District officials review this information and may shift ATON servicing work to another unit when the primary servicing vessel or unit is not available to provide the needed service in a timely manner. Another ongoing initiative the Coast Guard is exploring is the use of year-round buoys for ice prone areas to reduce servicing requirements. The Coast Guard has received positive feedback in two of the three districts where such buoys have been in service. Improving Capacity Limits at ATON Major Repair and Refurbishment Facilities: According to a Coast Guard official, the Coast Guard has had commercial contracts in District 9 (the Great Lakes region) and District 13 (the Pacific Northwest) going back decades to provide floating ATON major repair and refurbishment services. Then, in March 2019, WOPL awarded four regional commercial contracts to provide increased capacity for ATON major repairs and refurbishments in an effort to help reduce the Coast Guard’s floating ATON major repair and refurbishment backlog. Specifically, the Coast Guard (1) renewed the contract in District 13; (2) awarded a contract covering California (part of District 11); (3) awarded a contract for a zone covering New England and the Mid-Atlantic (Districts 1 and 5); and (4) awarded a contract covering Guam (part of District 14). According to Coast Guard officials, the addition or renewal of these four regional contracts has resulted in greater capacity and flexibility to reduce the floating ATON major repair and refurbishment backlog. While the Coast Guard has developed various initiatives to improve management of fixed and floating ATON, these initiatives do not contain certain elements, which limit assurance that the initiatives will be effectively implemented. For example, we found that many initiatives we evaluated do not contain milestone and completion dates for Coast Guard-wide implementation, which are elements that can guide decisions on the success of the initiatives. Under the foam buoy implementation initiative, the Coast Guard evaluated the use of foam buoys in lieu of steel buoys (which are more expensive to overhaul) and found that it was feasible to replace steel buoys with foam buoys in some locations but not in others. For example, the Coast Guard’s evaluations showed that foam buoys cannot stand up to ice conditions. On the basis of its evaluations, the Coast Guard plans to continue replacing certain classes of steel buoys with foam buoys where operationally feasible. However, the initiative does not contain milestone dates or desired outcomes for Coast Guard-wide implementation. According to guidance from the Program Management Institute, programs or projects—like the ATON-related initiatives being implemented by the Coast Guard—are to include specific, desired outcomes, along with the appropriate steps and time frames needed to achieve the final outcomes and results to implement the enhanced capabilities across the organization. In addition, our leading practices in capital decision- making state that such initiatives should include milestones and completion dates. According to Coast Guard officials, WOPL is a relatively new unit and is still developing ATON guidance and procedures for ATON-related initiatives and responsibilities to be performed by the districts. By updating its ATON-related initiatives to include the specific outcomes desired and timeframes for completing them, the Coast Guard would have better assurance that its initiatives to address ATON management challenges will be effectively implemented. Available Coast Guard data indicate that despite some slight declines in the condition of fixed and floating ATON, and increasing repair and recapitalization costs for floating ATON, the Coast Guard’s ability to meet its ATON mission did not show a marked decline during fiscal years 2014 through 2018. However, the future of the fixed and floating ATON and the vessels used to service them bears close watching given the challenges the Coast Guard faces in managing its fixed and floating ATON. The fact that many of the ATON have reached, or will soon be reaching, the end of their designed service lives could lead to an increase in the number of ATON requiring major repairs or replacement in the near future. According to Coast Guard data, the Coast Guard’s ability to refurbish or replace its aging ATON is made more challenging by limited capacity for conducting major repairs and refurbishments of floating ATON. The Coast Guard has taken positive steps to develop strategic plans to guide the ATON program, and these plans have led to the development of various initiatives to improve management of fixed and floating ATON, but these initiatives would benefit from the inclusion of certain elements, such as desired outcomes to be achieved and associated milestone dates, to have better assurance that the initiatives will be effectively implemented. The Commandant of the Coast Guard should direct the Assistant Commandant for Engineering and Logistics and Assistant Commandant for Prevention Policy to update the Coast Guard’s ATON-related initiatives to include the specific outcomes to be achieved and associated time frames. (Recommendation 1) We provided a draft of this report to DHS for review and comment. In its comments, reproduced in appendix II, DHS concurred with our recommendation and stated that the Coast Guard plans to review and update ATON-related initiatives to include specific outcomes with associated implementation milestones by December 31, 2020. DHS also provided technical comments that we incorporated into the report, as appropriate. We are sending copies of this report to the appropriate congressional committee, the Secretary of Homeland Security, and other interested parties. In addition, the report is available at no charge on the GAO website at http://www.gao.gov. If you or your staff have any questions about this report, please contact me at (206) 287-4804 or AndersonN@gao.gov. Contact points for our Offices of Congressional Relations and Public Affairs may be found on the last page of this report. GAO staff who made key contributions to this report are listed in appendix III. Figure 14 provides information on the cutters and boats that comprise the Coast Guard’s fleet of aids to navigation (ATON) vessels. In addition to the contact name above, Christopher Conrad (Assistant Director), Hugh Paquette (Analyst in Charge), Chuck Bausell, Breanne Cave, Benjamin Crossley, Dorian Dunbar, Michele Fejfar, Tracey King, Joshua Lanier, and Adam Vogt made significant contributions to this report.

Summary: One of the Coast Guard's statutory missions is the care and maintenance of ATON. Much like drivers need signs and universal driving rules, mariners need equivalent nautical “rules of the road.” As of November 2019, the Coast Guard managed 45,664 federal fixed and floating ATON that are designed to assist those operating in the U.S. Marine Transportation System, which includes about 25,000 miles of waterways, 1,000 harbor channels, 300 ports, and 3,700 terminals. According to the Coast Guard, as of July 2018, these ATON had a collective replacement value of about $1.6 billion. The Coast Guard has faced an array of challenges in managing its ATON, such as deteriorating buoys, and questions have been raised regarding the extent to which the Coast Guard is addressing these challenges. This report (1) describes what is known about the condition and costs of maintaining the Coast Guard's ATON, and (2) examines challenges the Coast Guard has experienced in managing its ATON and how it is addressing them. To address these issues, GAO reviewed ATON regulations and guidance, analyzed data on ATON condition and cost measures, collected input from all nine Coast Guard districts on ATON challenges, accompanied ATON units on mission activities, assessed agency initiatives using leading program management practices, and interviewed headquarters and field unit officials. The condition of the Coast Guard's aids to navigation (ATON), both fixed (e.g., lighthouses) and floating (e.g., buoys), have declined slightly while the overall costs for repairing or replacing them increased in recent years. According to Coast Guard data, its key metric for ATON condition—the Aid Availability Rate, or percentage of time that ATON are functioning correctly—declined from 98.0 to 97.1 percent during fiscal years 2014 through 2018, dipping slightly below the 97.5 percent target rate in fiscal years 2017 and 2018. During this time period, the overall costs to repair and replace ATON increased from about $12 million in fiscal year 2014 to about $20 million in fiscal year 2018. According to Coast Guard data, the majority of the costs for fixed ATON were spent on repairs whereas the majority of the costs for floating ATON were spent on replacements. The Coast Guard faces challenges in managing its fixed and floating ATON and has developed plans and initiatives to address them, but it has limited assurance that the plans and initiatives will be effectively implemented. According to Coast Guard officials, the challenges include decreased availability of vessels to service ATON, reduced ability to provide routine ATON servicing in a timely manner due to severe weather, among other factors, and limited capacity at ATON major repair and refurbishment facilities. The Coast Guard has developed plans to guide the ATON program, and these plans have led to the development and implementation of various initiatives at the headquarters and field unit levels to address these challenges. However, GAO found that the initiatives do not contain certain elements that help ensure effective implementation—such as desired outcomes and schedule milestones and completion dates—as recommended by leading program management practices. According to Coast Guard officials, they are still developing guidance and procedures for ATON-related initiatives that are to be implemented by the districts. By updating these initiatives to include certain elements, such as the specific outcomes desired and timeframes for completing them, the Coast Guard would have better assurance that its initiatives to address ATON management challenges will be effectively implemented. GAO recommends that the Coast Guard update its ATON initiatives by including the specific outcomes to be achieved and associated time frames. The Department of Homeland Security concurred with the recommendation.