Summary

ORIGINS OF THE STUDY

Through its Civil Works program, the U.S. Army Corps of Engineers (USACE) is responsible for planning, building, maintaining, and operating much of the nation’s water resources infrastructure for navigation and flood risk management. In particular, the maintenance, repair, rehabilitation, and modernization of water resource assets present demanding and costly challenges for USACE. The infrastructure assets and their components can be unique, built and manufactured at different periods for certain site-specific needs and conditions. In addition, these assets are subject to the stresses of water environments and to mechanical damage from vessels. Most of the navigation and flood risk management structures were built during the middle decades of the 20th century, meaning that a large majority of them have exceeded or will soon exceed their estimated design service lives of 60 to 75 years.

In the Water Resources and Development Act of 2016, Congress called for a study by an expert committee of the National Academies of Sciences, Engineering, and Medicine to consider the key demands and challenges facing USACE related to the condition and performance of its navigation and flood risk management assets; examine how innovative materials can support capabilities critical to meeting these demands and challenges; and make recommendations to inform strategies that USACE can pursue to further the development, demonstration, and deployment of promising materials in new and existing infrastructure.

The requested study, the results of which are documented in this report, was commissioned by the U.S. Army Engineer Research and Development Center (ERDC), which is USACE’s primary internal resource for research and development of innovative materials. ERDC maintains state-of-the-art knowledge of innovative materials and is actively working to get these materials into practice with the help of USACE’s Institute for Water Resources and Inland Navigation Design Center. ERDC identifies research needs through consultation with USACE’s 39 districts that manage civil works within the United States and its territories. Districts have significant autonomy in managing their infrastructure as they operate on the front lines, delivering projects and maintaining and operating the infrastructure in partnership with local communities and other stakeholders.

INFRASTRUCTURE FOCUS AREAS

The dams, locks, and levees that make up USACE’s inland navigation and flood risk management infrastructure are vital to commerce and the safety of communities. These aging assets contain thousands of individual components, which also reach and exceed their design lifespans along with the overall facility. Moreover, many components are unique to their specific lock or dam. Because the nation’s water resources infrastructure is essentially built out, with few new facilities being added and replacement projects being the focus of most new construction, maintenance, repair, and rehabilitation present many opportunities to use innovative materials to make the navigation and flood risk management systems more efficient and resilient. Thus, when considering USACE water resources activities that are most likely to accrue large and early benefits from the application of innovative materials, the study committee recognized the significance of the maintenance, repair, and rehabilitation of the nation’s aging inland navigation and flood risk management infrastructure.

USACE agreed with this assessment and the committee’s determination that the dams, locks, and levees that make up the inland navigation and flood risk management systems are most in need of strategic investments in innovative materials for their maintenance, repair, and rehabilitation. Moreover, the development of projects and allocations of the operations and maintenance (O&M) budgets that fund most maintenance, repair, and rehabilitation work have far more input from the districts when compared with capital funds budgeted for new and replacement construction, which must be authorized by Congress and executed according to specific plans and timelines. Accordingly, more opportunities exist for innovative materials to be introduced in O&M projects.

Innovative Materials Focus

Having considered the range and status of innovative materials that are currently or potentially useful in water resources infrastructure, the committee decided to provide a more in-depth review of the following three material types:

• Fiber-reinforced polymer (FRP) composite materials,
• High-strength concrete (HSC) and ultra-high-performance concrete (UHPC), and
• 3D-printed materials.

The committee learned from discussions with USACE and review of ERDC reports that these three material types in particular have the potential to confer benefits for USACE navigation and flood risk management infrastructure if utilized more often. The committee also observed that all three material types are already of high interest to USACE and have been the subject of significant laboratory and, in some cases, demonstration and pilot testing. Each is also supported by a substantial amount of research and implementation evidence from both the public and private sectors in water resources infrastructure and other domains. The first two materials listed are mentioned specifically in the Statement of Task. While the committee examined the three material types listed above in depth, opportunities for and experience with deployment of a number of other innovative materials were also explored, including coatings, lubricants, anchorages, and biogeotechnical materials.

THE DECISION-MAKING ENVIRONMENT

Districts submit infrastructure repair and maintenance needs as part of O&M budget requests, and once funded, they decide how to execute the projects. Therefore, any strategy to promote the use of innovative materials must include the districts and consider their decision-making environment, including budgeting. Because federal budget allocations for USACE Civil Works O&M are routinely substantially less than needed—work-deferred maintenance and repair exceeded $5 billion in fiscal year 2024—USACE’s budget process leads districts to spread funding to as many proposed projects as possible. For innovative materials that may require higher initial budgetary outlays but promise future budgetary savings from lower life-cycle costs, this dynamic can put their use at a disadvantage. Moreover, when districts are unfamiliar with an innovative material, they may not want to risk its use and may choose a conventional material whose performance characteristics are better known. Although USACE provides guidance that

encourages consideration of life-cycle performance and cost, there is no formal method for conducting such analyses for repair and maintenance alternatives.

Under these circumstances, the myriad small components of water resources infrastructure, such as floor and walkway grating panels, handrails, and electrical boxes, provide low-consequence opportunities for early applications of innovative materials to demonstrate performance. Discussions with USACE made clear that applications of innovative materials in small components will raise fewer concerns about unanticipated performance shortcomings than applications in larger and more expensive components such as gates, valves, and pumps. Spending on smaller components, as a first step for trial of innovative materials, may also be able to take advantage of the O&M budget process for “specific work not commonly performed.” For these O&M projects that are not routine and require only modest outlays, districts are afforded more decision-making latitude.

The O&M budget presents other challenges and opportunities for expanding the use of innovative materials. An important element of the budgeting process is USACE’s asset management system, which contains detailed inventories of assets and components and assessments of their condition. The system also contains assessments of the potential consequences of an asset failing or underperforming. The condition and consequence assessments are used to develop risk rankings of the O&M projects that are proposed for budget allocations. Assets and components that are in poor condition and subject to high consequences if this condition causes them to fail will receive the highest risk ranking.

Budget prioritizations using the risk ratings can work against the introduction of innovative materials because the engineering preference expressed in discussions with USACE is to demonstrate performance first in applications that are likely to have low consequences from failure, which are the very projects that are likely to rank low for funding priority. At the same time, however, the same risk rankings, if viewed differently, can identify candidate O&M projects for demonstrating the performance of an innovative material—that is, projects targeted to assets that are in poor condition and that do not have the potential for high consequence if the material underperforms.

Innovations in Materials and Material Technologies

USACE’s water resources infrastructure presents multiple opportunities to use FRP composite materials, HSC and UHPC, and 3D-printed materials for the maintenance and repair of infrastructure components. For these materials as well as for additional innovative materials explored by the committee, there are opportunities for further research and development

aimed at testing performance and formulating the protocols, specifications, and guidance to facilitate their application. USACE is furthest along in developing such guidance for FRP composite materials. For all materials and applications, long-term monitoring of performance is needed.

Although USACE has investigated and applied FRP composite materials for decades, their use remains limited. FRP has properties and performance characteristics that warrant investigations into more widespread applications. Potential benefits include being lighter weight and more corrosion resistant. FRP can be tailored to specific requirements and, as supported through examples in Chapter 4, holds the potential to reduce initial and life-cycle costs and shorten construction time. The U.S. Navy has significant experience with FRP composite materials in marine environments, from which USACE can learn. USACE has taken important steps toward its wider application for hydraulic components in the development of its Composite Material Applications and Research Roadmap (ERDC SR-24-3) and its Engineering and Construction Bulletin 2024-08, which provides interim policy and guidance that requires its engineers to consider FRP.

HSC and UHPC have demonstrated benefits including high strength, durability, impact and abrasion resistance, and crack control, which may lead to initial and life-cycle cost savings from their use in water resources infrastructure. Although ERDC has conducted extensive research on HSC and UHPC, knowledge transfer to and applications by the districts have been limited. The numerous applications of HSC and UHPC in other domains, such as transportation infrastructure and buildings, suggest that a body of knowledge exists that could be applied to water resources infrastructure.

Technologies for the 3D printing of metals and of concrete have advanced rapidly over recent decades. In the aerospace, automotive, and energy domains, metal 3D printing is used extensively. ERDC has also investigated the use of 3D-printed metal for the replacement of infrastructure components and has collaborated with districts on trial implementations for water resources infrastructure. ERDC’s work on 3D-printed concrete has been limited to military applications. To date, there have been no applications of 3D-printed concrete to water resources infrastructure, and questions surrounding the long-term performance and durability of printed concrete materials and structures remain largely unanswered.

For uses of other innovative materials in water resources infrastructure, ERDC has long stayed abreast of developments in coatings critical to the longevity of metals and other materials and has been investigating and deploying environmentally acceptable lubricants and self-lubricated materials. However, there are numerous other opportunities for innovative materials in water resources infrastructure. For example, there is a need for alternatives to carbon steel anchors. Although recent developments in ceramic anchors hold promise, long-term performance still needs to be

studied. As another example, biogeotechnology offers the potential for enhancing the performance of earthen structures and foundations. USACE has been a leader in deploying biopolymers to strengthen erosion resistance of earthen embankments, and additional biogeotechnology advances are on the horizon.

Barriers to and Drivers of the Use of Innovative Materials

Barriers to the adoption of innovative materials in USACE water resources infrastructure include an emphasis on minimizing initial budgetary outlays; limited awareness among district personnel of institutional experience with innovative materials; inadequate workforce technical knowledge and skills about innovative materials; and procurement constraints. Being the first to test an innovative material requires district personnel to use their limited resources on something that is viewed as not yet being tried and true. An aversion to taking such risks can hinder the adoption of innovative materials, and overcoming this aversion requires implementing measures that encourage district personnel to be more willing to innovate.

There are various drivers of USACE actions that can be leveraged to advance use of innovative materials. Congressional and USACE Headquarters mandates, directives, and guidance can influence the use of innovative materials. The USACE policy directives and guidance concerning life-cycle cost considerations, for example, can help counter the emphasis that is often placed on project initial cost. In addition, programs and other mechanisms that foster learning, disseminate best practices, and capture institutional knowledge can stimulate the use of innovative materials. USACE’s Communities of Practice and Centers of Expertise provide opportunities for advancing knowledge about use of innovative materials. USACE’s training programs for the use of FRP composite materials have been successful and may be models for other innovative materials. However, the USACE Proponent-Sponsored Engineer Corps Training program does not specifically include innovative materials. Opportunities also exist to leverage guidance and standards for the use of innovative materials from other domains, including in marine environments.

Demonstration programs for innovative materials, if designed appropriately, can address many of the barriers to the widespread adoption of innovative materials. Demonstration programs can reveal and document a material’s benefits, increase the confidence of potential users, provide data for qualifications and acceptance, and familiarize districts with the material and its implementation process. Demonstration programs have been used successfully in other domains, including in the highway industry and in the Department of Defense.

RECOMMENDATIONS

Findings and conclusions from the committee investigations led to a series of recommendations targeted at the applications of innovative materials for O&M projects, as these present opportunities at relatively small scale, cost, and risk, and with relatively rapid implementation. However, the focus on O&M does not preclude the use of innovative materials in future capital investment projects, and indeed will build experience for major rehabilitation projects and new construction. The recommendations are organized by theme, and are intended to support multiprong efforts for inducing systemic changes through both short- and long-term actions. Recommendations are directed to USACE, the study sponsor, and in some cases to the U.S. Congress, who requested the study. Recommendations directed generally to USACE refer to the USACE innovation ecosystem, an interconnected network of units, groups, and individuals at the district, division, and headquarters levels, and within ERDC, Communities of Practice, and Centers of Expertise. Action can be initiated individually or collaboratively within the USACE innovation ecosystem.

Prioritize, Facilitate, and Incentivize

Several study findings indicate that USACE should prioritize the evaluation of innovative materials for maintaining and repairing water resources infrastructure, and take deliberate, coordinated actions to promote and incentivize their use when benefits are identified. To support the goals of prioritizing, facilitating, and incentivizing the use of innovative materials, the committee recommends several key actions. Chief among them are appointing an advocate for innovative materials at USACE Headquarters, establishing dedicated funding for demonstration projects, and creating mechanisms to ensure that district personnel who make well-justified decisions to use such materials are recognized and supported.

Recommendation 1: USACE should designate a Headquarters (HQ) unit to coordinate and champion the use of innovative materials in the civil works infrastructure. Key functions would be to inventory, review, and report on the uses of innovative materials in the Civil Works program and to develop a roadmap to facilitate their use by the districts, including for water resources infrastructure. The roadmap should include plans for filling key research gaps by the U.S. Army Engineer Research and Development Center and others, conducting demonstrations and related evaluations to transition the materials more broadly in the water resources infrastructure. Indeed, this recommended HQ unit could play a key role in spearheading and supporting many of the additional recommendations in this report.

Recommendation 2: To counter aversion to risk, USACE Headquarters should explore ways for assuring district personnel that if they use an innovative material based on sound justification but nevertheless experience unsatisfactory performance, they will not be held at fault and will be provided the resources needed to rectify problems.

Recommendation 3: A district’s interest in maximizing the number of worthy projects funded through a fixed annual budget can lead to an undue emphasis on reducing each project’s annual budgetary allocation rather than over its lifespan. Therefore, USACE should consider requiring districts to develop budget models that compare the life-cycle budgetary impacts of conventional and innovative materials.

Recommendation 4: USACE should be open to the use of innovative materials for low-risk (i.e., low-consequence) maintenance projects that are not recurring or routine and where there are fewer established methods, such as for activities that fall under the operations and maintenance budgeting category “specific work not commonly performed.”

Recommendation 5: As it did for fiber-reinforced polymer by requiring the explicit and documented consideration of this material as an alternative to steel for new and replacement hydraulic structures (i.e., Headquarters Engineering and Construction Bulletin 2024-08), USACE should consider where policy guidance and direction could motivate the formal consideration of applications for other innovative materials. The myriad of water resource small components, such as floor and walkway grating panels, handrails, and electrical boxes, may be particularly suited for such policy guidance.

Recommendation 6: To motivate interest in innovative materials, USACE should make a point of recognizing and rewarding Civil Works personnel who have championed the beneficial use of innovative materials, perhaps by adding nominations guidance to the Incentive Award Program.

Monitor, Evaluate, and Demonstrate

Findings and conclusions of the study suggest the importance of long-term monitoring and evaluation of the condition and performance of water resources assets that use innovative materials as well as formal demonstration programs that have evaluation and verification phases as well as educational and promotional aims. Steps that USACE should take to further these interests are recommended.

Recommendation 7: USACE should establish a program dedicated to funding demonstration projects for the use of innovative materials in water resources infrastructure, seeking resources from Congress as necessary to fund the program as a special supplement to the annual operations and maintenance appropriation.

Recommendation 8: USACE should establish inspection protocols and reporting systems for projects that deploy innovative materials. Water resources infrastructure assets and components that use innovative materials should be subject to regular and long-term condition and performance monitoring and evaluation.

Recommendation 9: USACE should include in its asset management databases fields for recording the use of innovative materials in an asset or component, including details on the type of material and application. In addition, USACE should identify and gauge the condition and performance of assets and components that have previously used innovative materials.

Recommendation 10: USACE should leverage the data in its asset management system to identify candidate applications for demonstrating the use of innovative materials, including the system’s severity rating of the consequences of individual assets failing or underperforming. The ratings may be particularly helpful for identifying low-consequence applications that would otherwise go unfunded and where the demonstration of an innovative material with limited field experience would present minimal risk to the proposer.

Recommendation 11: USACE should ensure that all projects that are intended to demonstrate the use of innovative materials, including projects funded under the recommended dedicated program, are planned and designed with long-term condition and performance monitoring, evaluation, and reporting (as recommended above). USACE should develop processes to use data from the demonstration projects (and leverage data from other domains in similar environments when possible) to facilitate certification of innovative materials where needed.

Guide, Inform, Educate, and Train

Study findings and conclusions suggest that USACE should focus more attention on providing sufficient guidance and information on the uses of innovative materials in water resources infrastructure, as well as relevant

education and training opportunities for USACE personnel. Recommendations focus on leveraging and supporting existing mechanisms for these purposes.

Recommendation 12: USACE should harmonize and orient the existing body of standards, requirements, and guidance documents applicable to the use, qualification, and acceptance of innovative materials in water resources infrastructure. An early focus should be on materials that are supported by an existing body of standards and guidance such as for fiber-reinforced polymer application in hydraulic and marine structures and components by the U.S. Navy.

Recommendation 13: To foster learning, disseminate best practices, and capture institutional knowledge about the use of innovative materials, USACE should encourage participation by district and other USACE personnel in voluntary Communities of Practice. USACE’s Centers of Expertise should be assigned roles with appropriate budgets to steward and grow the base of knowledge on innovative materials.

Recommendation 14: USACE should offer a selection of technical and professional courses supportive of the use of innovative materials in water resources infrastructure through its Learning Center and Proponent-Sponsored Engineer Corps Training program. USACE should also encourage attendance at workshops, professional conferences, and college-level courses that focus on innovative materials. USACE Headquarters should encourage district leadership to promote and facilitate participation by district personnel in these activities.

Recommendation 15: USACE should support opportunities for USACE personnel knowledgeable in the use of innovative materials to provide technology transfer to external constituents through avenues such as workshops at professional conferences or lectures at universities.