Engineer Research and Development Center News Releases

Simulation of Dredged Material Placement in the San Francisco Bay Using a Multi-Dimensional Hydrodynamics and Sediment Transport Model

Press Operations — Thu, 11 Jun 2026 17:55:00 GMT

Abstract: The US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, has developed an Adaptive Hydraulics (AdH) 2D, hydrodynamic and sediment transport model for San Francisco Bay. This model supports the US Army Corps of Engineers, San Francisco District, in informing navigation and sediment management decisions as part of the Regional Dredged Material Management Plan (RDMMP), which evaluates dredging methods and placement alternatives over a 20-year planning horizon. There is a need to assess the long-term fate of dredged material placed at in-bay sites to better understand associated benefits and potential impacts. This report documents the development, calibration, and validation of the AdH 2D model for conditions in 2022. The model was applied to simulate the multimonth dispersion and transport of dredged material from four sites. Model results demonstrate that sediment transport patterns are influenced by seasonal hydrodynamic forcing and grain-size composition, with coarser material forming stable deposits that persist over time. The findings of this study inform sediment management strategies under the San Francisco Bay RDMMP and support efforts to reduce navigation risks and enhance beneficial use opportunities. The study recommends field data collection to improve sediment characterization at placement sites and strengthen predictive modeling and planning efforts.

Proceedings from the Great Lakes Engineering With Nature® Natural and Nature-Based Features Playbook Workshop

Press Operations — Thu, 11 Jun 2026 17:53:00 GMT

Abstract: Communities in the Great Lakes are experiencing increased frequency in coastal flooding and erosion, causing property damage, putting lives at risk, and disrupting local economies. To address these challenges, two workshops were conducted (18 February 2025 [virtual] and 26–27 February 2025 [in person]) to collect knowledge, insights, and feedback from community members, policymakers, and Tribal Nations representatives to inform the development of the Engineering With Nature® Great Lakes Playbook. This report documents the workshop outcomes. The playbook is being designed to advance coastal resilience efforts in the region by identifying natural and nature-based features and multiple lines of resilience strategies that address unique natural hazard-related challenges of the Great Lakes. During the workshops, sustainable, resilient, adaptable, and cost-effective solutions were explored and construction and implementation feasibility were discussed along with regulatory and community challenges that are applicable to coastal risks and opportunities around the Great Lakes. By providing location-appropriate examples and clear guidance on how these nature-based and engineered solutions can be implemented, the playbook will enhance understanding of their potential performance in the region and build confidence among federal, state, and local agencies and Tribal Nations in planning, designing, and implementing these sustainable, adaptable, and cost-effective solutions.

Geofencing for Standardized Navigation Lock Cycle Time Analysis

Press Operations — Thu, 11 Jun 2026 17:51:00 GMT

Abstract: The purpose of this US Army Engineer Research and Development Center (ERDC) technical note (TN) is to describe the motivation for, and development of, a set of geospatial boundaries (geofences) at standard intervals around navigation lock structures owned or operated by the US Army Corps of Engineers (USACE). These geofences will be used for automated time-stamp generation in conjunction with Automatic Identification System (AIS) broadcasts from vessels.

Multisource Knowledge Graph Architecture for Air-Gapped AI Systems: Design Patterns and a Geospatial Reference Implementation

Press Operations — Wed, 10 Jun 2026 12:53:00 GMT

Purpose: This technical note presents a reference architecture for constructing multisource knowledge graphs in air-gapped, domain-specific AI systems. The architecture addresses recurring problems in military, intelligence, and secure-enterprise environments: integrating heterogeneous authoritative data sources while preserving source schema fidelity, enabling deterministic semantic resolution, and operating without external network dependencies. While this is a geospatial implementation, the architectural principles in the core design are transferable. The implementation is organized around four separable layers—schema registry, domain ontology, reasoning patterns, and relationship vocabulary—and adopts a canonical-with-aliasing integration strategy that supports cross-schema reasoning without forcing premature schema con-vergence. These patterns are validated through a geospatial intelligence implementation supporting US Army operations and demonstrate how abstract design principles translate into an operationally relevant system. This knowledge graph is designed to serve as the semantic substrate for router-based AI systems. A companion technical note (Drouillard and Lewis 2026) describes the geospatial AI (GeoAI) agent stack, which is a router-based orchestration architecture that coordinates multiple retrieval backends and reasoning tools. Within that architecture, the knowledge graph functions as a specialized retrieval backend that runs alongside document retrieval and vector search, serving queries that require structured entity-relationship reasoning, provenance tracking, or deterministic semantic resolution. The router directs spatial relationship queries (e.g., “which roads cross this river”), multihop dependency queries (e.g., “what infrastructure depends on this power station”), and schema-resolution queries (e.g., “find all transportation features in Multinational Geospatial Co-production Program [MGCP] format”) to the knowledge graph while routing conceptual or analytical questions to document retrieval. This technical note focuses exclusively on the knowledge graph architecture; the broader orchestration patterns and routing logic are detailed in the companion paper. While the examples presented are geospatial, the architectural principles, validation strategies, and design tradeoffs documented here have broader applicability where deterministic semantic integration is required under air-gapped constraints. The geospatial instantiation serves as a concrete demonstration of abstract patterns that may inform future knowledge graph efforts in other US Army Engineer Research and Development Center (ERDC) research domains.

Considerations for Potential Use of an Agent-Based Model in a Petri Network Framework to Model Roost Tree Dynamics of Bats

Press Operations — Tue, 09 Jun 2026 20:36:00 GMT

Purpose: The US Army Corps of Engineers (USACE) is responsible for numerous projects that involve altering or removing wildlife habitat, including habitat of species listed as threatened, endangered, or sensitive (TES). Before initiating a project that may affect TES species, USACE must determine the project’s impact to these species. Understanding the degree of impact, both positive and negative, allows USACE to compare alternatives to reduce negative effects. Because of this, USACE planners need tools to provide accurate assessments of project impacts. Conservation efforts for bats have focused on protecting habitat, especially diurnal roosting trees. Roost trees serve not only as daytime shelter for bats but also for rearing pups until they are able to fly (Barbour and Davis 1969). Determining the impact of habitat change by empirically testing the response of bats to habitat modification has proved difficult because of the effects it may have on TES bats as well as its cost. Simulating the effects of habitat change using computer models provides an excellent data alternative for USACE planners. This technical note explains how agent-based models within a petri network framework can provide USACE planners with information on how habitat modification will affect bat presence or absence.

Considerations for Potential Use of an Agent-Based Model in a Petri Network Framework to Model Roost Tree Dynamics of Bats

Press Operations — Tue, 09 Jun 2026 12:51:00 GMT

Metabarcoding Stem Residue as a Novel Environmental DNA (eDNA) Tool to Identify Spread of Phragmites australis Biological Control Agents

Press Operations — Mon, 08 Jun 2026 20:46:00 GMT

Abstract: Detection and monitoring of biological control agents are critical for evaluating their establishment and spread yet remain challenging when species are cryptic, and densities are low. We assessed whether environmental DNA (eDNA) metabarcoding of stem residues could be used to detect and distinguish the stem-boring noctuid moths Archanara neurica and Lenisa geminipuncta, biological control agents of introduced Phragmites australis released in Ontario, Canada. Using 16S rDNA metabarcoding supplemented with newly generated reference sequences, we analyzed stem residue samples spanning a gradient of quality, including laboratory culture stems (in which agent larvae were present at the time of sampling), conﬁrmed Canadian release sites, and degraded stems from un-managed Phragmites stands in western New York, USA. Target species were consistently detected in laboratory samples, where they comprised 76.7–100% (L. geminipuncta) and 79.2–100% (A. neurica) of Lepidoptera reads. At Canadian release sites, A. neurica was detected in 5 of 11 samples and L. geminipuncta in all 10 samples, with relative read abundances ranging from trace levels to > 90%. Among 27 damaged stems collected in the United States, A. neurica and L. geminipuncta DNA was detected in three samples at very low abundances (0.003–0.12% of total reads), representing the ﬁrst molecular evidence consistent with trans-border dispersal of these agents. Although detections were rare and do not conﬁrm population establishment, results demonstrate that stem-residue eDNA metabarcoding provides a sensitive, non-invasive tool for early detection and post-release monitoring of biological control agents for invasive plants.

Evaluating Migratory Fish Passage at Partial Migration Barriers in a Social-Ecological Riverscape

Press Operations — Mon, 08 Jun 2026 19:53:00 GMT

Abstract: Anthropogenic partial barriers, such as low-head locks and dams, fragment social-ecological riverscapes and limit migratory ﬁsh access to historical spawning habitats, creating trade-offs between ecological conservation and human needs. Fish passage mitigation strategies at three low-head locks and dams on the Cape Fear River, North Carolina, across two contrasting mitigation regimes included (i) a nature-like ﬁshway at LD1, (ii) conservation locking at LD2 and LD3, and (iii) environmental ﬂow prescriptions when locks were inoperable. We evaluated passage of American shad and striped bass using acoustic telemetry and multistate models within a Bayesian framework to estimate upstream passage probabilities under varying ﬂow conditions and management regimes. Passage probabilities for both species were higher in 2013–2015 when conservation locking was conducted. In contrast, passage declined when locks were inoperable and only e-ﬂows allowed passage during dam submergence events in 2022–2023. Flow positively inﬂuenced passage, with strongest effects for striped bass; however, the nature-like ﬁshway exhibited consistently low passage probability, and modiﬁcations did not improve passage probabilities. Given low passage probabilities during the recent mitigation period, improving longitudinal connectivity for diadromous ﬁsh in this river necessitates ﬂexible, integrated operational, structural, and ﬂow-based strategies. Possible future mitigation actions to improve ﬁsh passage could include resuming conservation locking, structural interventions such as bypass channel construction and dam height lowering that extends dam submergence, and continued use of e-ﬂows.

Emulation of Peak Storm Surge Across Extended Spatial Domains Using Separable Gaussian Process Techniques

Press Operations — Mon, 08 Jun 2026 19:51:00 GMT

Abstract: Data-driven emulation of peak storm surge has emerged as a popular strategy for overcoming limitations arising from the computational burden of high-ﬁdelity hydrodynamic numerical models used within coastal risk assessment applications. The surrogate models used for this emulation are developed using suites of synthetic storm simulations, and once calibrated, can replace the original high-ﬁdelity model to establish predictions for new storms. These predictions pertain to the geographic domain, and therefore nodal locations, covered by the original high-ﬁdelity simulation suite. This creates a two-dimensional space for the peak surge predictions, with one corresponding to the storm features and the other to the spatial domain. Gaussian Process techniques have emerged as a widely popular surrogate modeling technique for peak surge emulation. In all GP implementations so far, the spatial variability has been incorporated in the analysis through the metamodel output, considering a multi-output GP implementation. This approach fails to explicitly model spatial dependencies for the peak surge. To address this shortcoming, this study examines an alternative implementation that considers spatial and storm feature variability as part of the metamodel input, establishing a surrogate model that simultaneously predicts the peak storm surge across both the spatial domain and the storm features. For computational tractability, a separable covariance function is considered for the GP, establishing separate kernels for the spatial and storm feature spaces. Particularly for the spatial domain, an adaptive covariance tapering formulation, which infuses sparsity in the corresponding covariance matrix, is adopted to support applications with a large number of nodal locations. A simultaneous calibration approach for the hyperparameters of the separate kernels is further proposed to improve emulation accuracy. Comparisons of computational efﬁciency and accuracy of the alternative GP implementations are established utilizing the Coastal Hazards System–North Atlantic database, with those employing the adaptive covariance tapering formulation evaluated under varying sparsity levels. The case study demonstrates that the simultaneous hyperparameter calibration is beneﬁcial for the separable GP's predictive accuracy, particularly as it relates to the worst-performing nodes in the domain, and that the imposed sparsity level impacts the separable GP's ability to model non-stationary spatial trends in the domain.

MoistViT: A Vision Transformer Model for Moisture Content Prediction of Wood Chips

Press Operations — Mon, 08 Jun 2026 19:49:00 GMT

Abstract: Moisture content in wood chips is a critical parameter for industries such as pelleting mills, bio-refineries, paper mills, and renewable energy production. The moisture level significantly influences both the quality of the final product and the efficiency of the production process. Consequently, accurate knowledge of moisture content is of substantial importance to wood chip-reliant industries. However, current methods for determining moisture content are either time-consuming or require costly equipment and specialized setups. Therefore, developing a quick and reliable method for assessing wood chip moisture content is imperative. To address this need, we evaluate fourteen Vision Transformer (ViT) architectures and introduce an optimized model, MoistViT, developed using Bayesian Optimization Hyperband (BOHB) for efficient hyperparameter tuning. Experiments on two wood chip image datasets (1600 total images) show that MoistViT achieves 91% accuracy and 92% F1-score on Source 1 and 93% accuracy and 93% F1-score on Source 2, outperforming all baseline models. Subsequently, a thorough analysis of failure cases has been carried out, including the identification of the most challenging groups of moisture levels. These analyses provide valuable insights into the complex task of determining moisture content from inherently heterogeneous wood chips. The proposed MoistViT demonstrates significant potential for real-time applications in relevant industries, which could ultimately lead to a streamlined production process.

Environmental DNA Metabarcoding Elucidates Freshwater Mussel Diversity and Occupancy to Facilitate Improved Management and Conservation

Press Operations — Fri, 05 Jun 2026 15:35:00 GMT

Abstract: Freshwater mussels are considered among the most at-risk taxa in the world. As such, comprehensive monitoring assessments of what abiotic and biotic factors influence mussel occupancy will be vital for guiding effective conservation. Here, we analysed vertebrate and mussel environmental DNA metabarcoding data to explore the influence of biotic and abiotic factors on freshwater mussel populations. This study utilised water samples and tactile survey data collected from streams throughout Fort Johnson, Louisiana. Methods: We first evaluated the effectiveness of eDNA metabarcoding for characterising freshwater communities based on previous conventional tactile surveys. Next, we used eDNA metabarcoding analysis for freshwater mussels and vertebrate species alongside GIS-derived satellite remote sensing data to assess how various biotic and abiotic variables impact freshwater mussel eDNA occupancy. Our eDNA metabarcoding survey largely agreed with both historical and contemporary surveys on Fort Johnson, while uniquely detecting Louisiana pigtoe, a proposed threatened species under the US Endangered Species Act. We also found that eDNA detections and occupancy had strong seasonal variation, with increased read abundance and diversity in the spring. Vertebrate, fish, and predator diversity were strongly predictive of mussel occupancy, supporting the concept of land managers focusing on the entire ecosystem for mussel conservation. Lastly, we found that percent forest cover and drainage basin size influenced mussel eDNA occupancy, informing habitat associations for mussel species of interest. Our results demonstrate that combining eDNA metabarcoding of target and non- target species with occupancy modelling can provide insights into the ecology of freshwater mussels and is a useful tool to improve their conservation and management.

Multitemporal Change Detection in the Coastal Zone: Literature Review

Press Operations — Fri, 05 Jun 2026 15:33:00 GMT

Abstract: Beach volume change is a primary metric for quantifying coastal change due to physical and anthropogenic forces. Volumes provide key inputs for the creation and maintenance of regional sediment budgets that inform engineering decisions and ensure the effective management of sediment. This special report provides a comprehensive literature review of the state of the art for developing beach volume change metrics, including methods, software and tools, and common sources of error. The reviewed literature indicates that common proxy-based methods for developing volumes (e.g., shoreline change analysis and beach profile change analysis) are limited in their applicability for study areas with alongshore geomorphic variability. A digital elevation model (DEM) of difference method used with high-resolution (e.g., 1 m DEM) datasets captures volumes over spatially variable geomorphologies more accurately; however, the literature notes limitations related to elevation dataset coverage and geometries used for aggregating volume quantities. Space-time cube methods enable cell-by-cell comparisons of volumes over multiple time periods within defined neighborhoods and provide additional insights, efficiencies, and flexibilities to afore-mentioned methods. A new beach volume framework is required to address limitations related to geomorphic variability, aggregation units, and dataset coverage.

Brief Overview and Guide to Developing Monitoring and Adaptive Management Plans

Press Operations — Thu, 04 Jun 2026 15:31:00 GMT

Purpose: The purpose of this technical note is to summarizes key points on monitoring and adaptive management from the more detailed US Army Corps of Engineers (USACE) report ERDC/EL SR-19-9, “A Systems Approach to Ecosystem Adaptive Management: A USACE Technical Guide” and to provide a quick guide to developing monitoring and adaptive management plans (MAMPs) relevant to ecosystem restoration and mitigation projects. Although this report was written specifically for USACE projects, it is applicable to most restoration and mitigation projects. This guide does not supersede current or future USACE policy or guidance, nor is it applicable to private mitigation projects regulated by USACE.

PFAS Interactions with ASTM Fat Clay and ASTM Ottawa Sand: Implications for Contamination from High-Concentration PFAS Sources Using Fourier Transform Infrared (FTIR) Spectroscopy

Press Operations — Thu, 04 Jun 2026 15:29:00 GMT

Purpose: This technical note seeks to understand the impact of high per- and polyfluoroalkyl substances (PFAS) concentrations on soils, specifically fat clay and Ottawa F-65 sand. This technical note also aims to understand the absorption and retention behaviors of PFAS in these two soil types and how the behaviors may vary because of the soil’s distinct properties.

Efficacy of UVC Treatment on Hydrilla verticillata and Trapa spp.

Press Operations — Thu, 04 Jun 2026 15:27:00 GMT

Abstract: Hydrilla verticillata and Trapa spp. are invasive aquatic plants that pose serious challenges to freshwater ecosystems. In search of a nonchemical method to eradicate H. verticillata and Trapa spp., this study explores the application of UVC light to target the adult plant forms and the dormant turions of H. verticillata as well as the seedlings of Trapa spp. Contrary to our expectations, the experimental results demonstrated that UVC exposure had no significant effect on reducing the viability of either adult hydrilla plants or their turions. Despite treatment with a range of UVC doses, the plants remained viable and the turions were able to germinate successfully. UVC exposure did, however, cause a significant reduction in biomass for both Trapa species tested. These findings suggest that UVC light, at least under the conditions tested, is not an effective standalone strategy for controlling hydrilla but may be a useful nonchemical tool for controlling Trapa spp. Further research is required to explore alternative nonchemical methods or to refine the application parameters of UVC if it is to be further considered for eradication of these two invasive aquatic plants

Operational Analysis of Composting for Military Installation Resilience

Press Operations — Mon, 01 Jun 2026 19:57:00 GMT

Abstract: On military installations, food waste is the heaviest portion of solid waste. At a single installation, food waste and its management can contribute up to $1.5 million lost annually. Additionally, Army installations pay over $100 million annually in disposal fees. Army policy calls for source reduction and composting as preferred methods of waste management over landfilling. As of 2025, 11 states and Washing-ton, DC, have laws that restrict food waste from being landfilled, with some laws more stringent than others. Composting is one way to align with both Army policy and local laws. Several installations have on-post composting operations, and others send food waste to nearby commercial compost facilities, where those are available. In FY 2024, 33 installations reported food recycling, which includes composting, anaerobic digestion, and other food-waste diversion. If composting on-post, a suitable location, equipment, and labor are needed. Multiple methods of composting for an installation must be considered. But composting can be worthwhile and may be more economical than landfilling. When installations are deciding how to manage food waste, they should consider their resources, organic waste generation tonnage, labor availability, and potential for cost savings. Depending on their location, on-post and off-post commercial options may be possible.

Encouraging USACE Implementation of Engineering Critical Assessment (ECA): A Pre-ECA Screening Tool and Fracture-Resistance Screening Tool

Press Operations — Thu, 28 May 2026 19:35:00 GMT

Abstract: The US Army Corps of Engineers (USACE) manages a large inventory of hydraulic steel structures (HSS). These HSS are aging, and upon inspection, many show signs of damage including large discontinuities in their members, which threaten the HSS operation. Simply repairing every discontinuity will ensure continued HSS operation but may be unnecessarily expensive. Therefore, USACE seeks to balance its constrained budget with safe, reliable HSS operation. One balancing method is the concept of fitness for service. A discontinuity is evaluated using an acceptance criteria based on the principles of structural analysis and fracture mechanics called an engineering condition assessment (ECA) that decides whether it is fit for service. If a discontinuity is fit for service, the HSS will continue regular operations; if it is not fit for service, the discontinuity will be considered a defect and repaired. However, USACE has not widely adopted ECA. Because of resource constraints, engineers often choose to conservatively repair without considering ECA. This study seeks to alleviate the difficulty in committing resources to an ECA in two ways: (1) by providing logical justification for performing an ECA and (2) by reducing the resources necessary for analysis by providing a fracture-resistance screening tool.

Multi-Temporal Geomorphic Change and Application of the Coastal Engineering Resilience Index Along the Mississippi Mainland Beaches and Dunes

Press Operations — Wed, 27 May 2026 18:43:00 GMT

Abstract: This report addresses the Mobile District’s request for a representative resilient beach and dune profile for the Mississippi mainland beach and dune project. The report summarizes a workflow that uses a custom ArcGIS Pro toolbox and 10 lidar datasets spanning a 22-year period of analysis. The workflow involves (1) lidar data compilation; (2) the extraction of geomorphic features, such as shorelines and dune toes and crests, on over 5,800 profiles along the Mississippi mainland coast; (3) the calculation of Coastal Engineering Resilience Index values for each transect for each lidar dataset; (4) selection of representative resilient profiles for various datasets; (5) development of synthetic profiles and Coastal Engineering Resilience Index (CERI) calculations on those profiles; and (6) data delivery and the development of a Web service hosting the project outcomes. The results of these analyses indicate that the protective width (i.e., from the shoreline to the seawall along the coast) is a major contributor to the resilience of a given section of beach. However, the resilience of these estuarine beaches can also be enhanced by increasing protective elevation. Overall, the work demonstrates the value of applying these workflows and toolboxes during the engineering planning and design phase.

Financing Natural Infrastructure: Hunter’s Point South, Queens, New York

Press Operations — Tue, 26 May 2026 19:50:00 GMT

Purpose: Greater application of natural infrastructure (NI) approaches calls for more widely accessible information about leveraging resources and opportunities to design, construct, monitor, and adaptively manage projects that incorporate natural features. Because NI techniques vary widely by location, purpose, and scale, no standard process currently exists for securing funds and establishing financing mechanisms. This document is part of a series sharing lessons learned and showcasing successful examples of developing and implementing NI projects through innovative partnerships, funding, and financing strategies. The series is intended for federal and nonfederal practitioners who play a role in the planning and management of NI projects worldwide. This technical note describes the development and funding process for the Hunter’s Point South waterfront park development, a community-driven initiative that transformed an abandoned postindustrial site into a multipurpose recreational space with enhanced coastal flood protection and affordable housing. Hunter’s Point South achieves a long-standing vision for Long Island City’s waterfront and serves as a model for accessible, climate-resilient design. This research effort is a collaboration between the Engineering With Nature® (EWN®) and Systems Approach to Geomorphic Engineering (SAGE) programs of the US Army Corps of Engineers (USACE).

Evaluation of Shore Protection Alternatives at Crescent Beach, Indiana

Press Operations — Thu, 21 May 2026 14:05:00 GMT

Abstract: This report documents a numerical modeling investigation of shore protection alternatives at Crescent Beach, Indiana. The integrated flow, wave, sediment transport, and morphology change Coastal Modeling System (CMS) and the long-term shoreline evolution model, GenCade, were applied to evaluate alternatives. Sediment, elevation, and hydrodynamic data were collected nearby to improve model calibration and validation. Eight alternatives were evaluated, with coastal structures in four, beach nourishments in three, and one with both. Structures other than the continuous rubble ridge (Alternative 4) had minimal or negative influences on sediment transport. Stone sizes and costs were estimated for Alternative 4 using StormSim and extremal forcing from the Coastal Hazards System (CHS) Great Lakes Study, but CMS does not predict impacts that justify rubble ridge construction costs. CMS and GenCade were applied to beach nourishments across a range of volume and sediment grain size distributions. Model evaluations indicate that beach nourishment is the most effective shoreline protection technique, using coarse sand mixed with small stones to achieve a median grain size (d50) of 1.80 millimeters successfully extends the beach nourishment lifecycle, and increasing nourishment volume to 87,455 cubic meters to span in front of Mount Baldy substantially increases downdrift benefits.