12 Feb 2026

Numerical Study of Submergence-Induced Forces on a Maintenance Bridge

Abstract: The US Army Engineer Research and Development Center–Coastal and Hydraulics Laboratory conducted a numerical study for a proposed maintenance bridge over the Trinity River in downtown Fort Worth, Texas, that will be submerged in flood conditions. The purpose of this study was to determine the hydrodynamic loads on the structure. The study found that, due to a combination of peak velocities and water depth, a return period of 500 yr generates the largest drag forces, while the higher depth and discharge of the standard project flood generate larger lift forces. Two flow structures were observed with shallow submergence: The first resulted in a jet parallel to the deck with a recirculation extending from railing to railing and the second resulted in a plunging jet over the deck with smaller but stronger recirculation. These patterns resulted in significantly different loads on the structure. The study analyzed the bridge’s deck slope to the flow as a possible variable affecting the loads. Observed changes related mostly to the flow pattern predicted for different flow configurations. Finally, it was observed that an open railing provides the best possible conditions in terms of loading; therefore, minimizing the frontal area of the railing is recommended.

12 Feb 2026

Investigation of Graphene Nanoplatelets for Adsorptive Removal of Aqueous Munitions Compounds 2,4,6-Trinitrotoluene (TNT) and Hexahydro-1,3,5-Trinitro-S-Triazine (RDX)

Abstract: Graphene nanoplatelets (GnPs) were evaluated against munitions compounds 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-s-triazine (RDX) in aqueous solutions for adsorptive removal performance. Fourier transform infrared and Raman spectroscopy were employed to characterize samples and inform adsorption mechanisms. Adsorption kinetics and isotherm studies were conducted in deionized water and compared with granular activated carbon (GAC). Evaluations were conducted with varying pH levels, ionic strengths, and temperatures and with surface water solutions to assess the impact of environmental factors on performance and further inform adsorption mechanisms. This study demonstrated that GnPs exhibited more rapid adsorption than GAC. Furthermore, TNT was adsorbed with greater capacity by GnPs compared to GAC, while GnPs removed RDX in greater capacity only when results were normalized for surface area. The more planar structure of GnPs may have contributed to performance enhancements relative to GAC. Adsorption was not impacted by variations in pH or ionic strength, indicating stable performance in different environments. Thermodynamic analysis indicated that removal was more favorable at higher temperatures. Furthermore, π-π interactions likely facilitated TNT removal by GnPs, while RDX was removed through physisorption by van der Waals forces. This study advanced understanding of environmental management of munitions compounds, as the adsorptive performance of GnPs for munitions compounds in solutions within a natural environmental matrix were evaluated, and key mechanisms supporting adsorptive removal of these compounds were informed. Overall, this study demonstrated the effectiveness of GnPs in treating water contaminated with TNT or RDX, particularly when rapid adsorption is preferred.

12 Feb 2026

Mechanical Properties and Microstructure of Annealed Ni/CrC-NiCr Metal Matrix Composite Prepared by Cold Sprayed Deposition

Abstract: This study investigates the effects of low (700 ◦C) and high (1000 ◦C) temperature annealing on the micro-structure and mechanical properties of two metal matrix composites consisting of Ni and two separate compositions of CrC-NiCr cold-sprayed onto A-514 structure steel. The mechanical properties, including tensile strength, ductility, interface shear strength, and microhardness, were evaluated after heat treatments. Additionally, scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), and transmission electron microscopy (TEM) were used to characterize the microstructure of the annealed deposits. The results showed that annealing significantly enhanced the inter-splat bonding quality between the matrix (nickel) particles. However, higher temperature annealing led to an increase in voids surrounding the cermet particle due to enhanced elemental diffusion. Furthermore, the interparticle bonding between the nickel particles in the matrix and the cermet particle was also improved after annealing. Depending on the composition, the ultimate tensile strength increased by a minimum of 32 %, and the adhesion shear strength improved by over 77 % following annealing at 1000 ◦C. Recrystallization and reduction of the dislocation density in the nickel matrix occurred within the splats during annealing, resulting in increased ductility from less than 0.2 % in the as sprayed condition to more than 6.5 % after annealing. However, a general reduction in hardness was observed after annealing. The interplay between the annealing temperature, microstructural evolution, and mechanical performance demonstrates that the improved bonding directly influenced the mechanical properties, resulting in increased tensile strength, greater ductility, and a shift from brittle to ductile fracture behavior as the micro-structure evolved.

12 Feb 2026

The Acoustic-Doppler Current Profiler (ADCP): A Comprehensive Tool for River Hydromorphodynamics Monitoring

Abstract: This paper introduces the use of acoustic Doppler current profiler (ADCP) measurements as input for the Acoustic Mapping Velocimetry (AMV) method, a technique for characterizing the dynamics of riverine bedforms. The performance of this new approach, ADCP-AMV, is compared with input from a multibeam echosounder through a field study conducted on the Mississippi River (USA). A virtual ADCP tool has been created to support the ADCP-AMV measurements with optimal data density predictions. To the authors’ knowledge, this is the first time ADCP measurements have been used in conjunction with the AMV dune-tracking method. Subsequently, the paper discusses the coupling of ADCP-AMV measurements with ancillary data extracted from the ADCP. These ancillary data are processed using previously developed protocols to characterize hydrodynamics and the suspended sediment distribution in the water column. This paper emphasizes the capability of ADCPs to characterize open-channel river hydromorphodynamic parameters with high spatiotemporal resolution. Recommendations to accurately and efficiently acquire these multi-variable measurements and derived datasets are discussed.

12 Feb 2026

Growth Patterns of Three Hydrilla Verticillata Biotypes in the United States

Abstract: Hydrilla [Hydrilla verticillata (L.f. Royle)] is an invasive submersed plant first documented in the United States (US) in the 1950s. Until recently, only two distinct strains of hydrilla, hereafter referred to as biotypes, were recorded in the US with both belonging to the same clade and characterized as either ‘monoecious’ or ‘dioecious’. In 2016, a third genetically distinct biotype (‘clade C’) was identified in the lower Connecticut River, Connecticut. Trials were conducted at two geographically unique locations within North Carolina to compare growth and reproduction of hydrilla biotypes by climatic conditions. Nominal differences were observed in peak aboveground biomass, relative growth rate, or occurrence of these metrics among the three hydrilla biotypes, although the predicted peak biomass for dioecious hydrilla did not occur during the study period. Monoecious hydrilla exhibited lower peak belowground biomass than dioecious and clade C hydrilla despite its abundant subterranean turion production. Monoecious hydrilla exhibited 1.8X greater aboveground biomass 180 days after planting (Julian day 304) than clade C hydrilla. Clade C hydrilla produced 74 axillary turions per plant on Julian day 304, which equates to a 2.3X increase over monoecious hydrilla and 61.5X increase over dioecious hydrilla. Conversely, subterranean turion production was 4.7 and 7.1X higher in monoecious hydrilla and dioecious hydrilla than clade C hydrilla, respectively. These studies suggest the clade C hydrilla displays many phenological similarities to the other two biotypes in the US, but its prodigious axillary turion production poses concerning implications for potential to spread and persistence following management.

11 Feb 2026

Assessing Relative Wetland Flood Risk Management Benefits Using COPE: An Exploration of Capacity, Opportunity, Payoff, and Efficacy

Abstract: Wetlands reduce flood risk, but measuring their performance and benefits is challenging due to the highly variable nature of the factors, including landscape features, land use, and climate, that shape flood response. An evidence-based index was developed to rapidly assess the potential flood risk management benefits of wetland restoration. These benefits are measured by combining the Capacity (C), Opportunity (O), Payoff (P), and Efficacy (E) indicators into a single index, called COPE. Capacity captures the internal wetland characteristics that alter flood peak attenuation potential. Opportunity reflects watershed characteristics that control the effectiveness of internal wetland capacities. Payoff quantifies the population exposed to high flood risk, and Efficacy reflects the ability of communities to respond to flooding. Literature evidence for the C and O indicators suggests that flood risk is reduced by increasing wetland storage in small basins with hillslopes or in moderate to large riverine basins. Literature evidence for the E index suggests that multiple indicators can capture the potential for disproportionate harm to vulnerable communities. A case study demonstrated that the P indicator strongly influences the relative-benefits score produced by COPE, but the C, O, and E indexes can alter the score substantially when values deviate from average conditions.

11 Feb 2026

Oyster Reef Ecosystem Recovery Monitoring: A Habitat Case Study for the US Army Corps of Engineers Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network

Abstract: Oyster reefs are native to oceanic coasts of the contiguous United States, are great contributors to secondary production in estuaries, and provide food and other services to humans. Unfortunately, oyster reefs have become functionally extinct throughout much of their historical range due to overharvesting, disease, poor water quality, and weather-related drivers. Restoration efforts are underway in response to these population collapses and seek to replenish oyster populations to a level sustainable for ecosystem services. To evaluate effectiveness of these restoration interventions and characterize oyster reef recovery status on large scales, coordinated monitoring is needed to facilitate long-term collection, storage, and dissemination of data. The US Army Corps of Engineers has proposed the development of the Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network, a monitoring system composed of nationwide restoration and reference sites, to generate high-quality, replicated datasets to address large-scale ecosystem restoration challenges. This report details a framework of recovery attributes and associated monitoring metrics and methods proposed to characterize oyster reef habitat recovery following ecosystem restoration interventions. Monitoring recommendations, as well as existing monitoring networks and communities of practice, are discussed as key potential facets and partners in the operationalization of ARMER.

10 Feb 2026

Improving Dredging and Beneficial Use Project Implementation: Review of Critical Data Needs, Technical, and Market Factors

Purpose: This technical note summarizes key results from an applied research study funded by the US Army Engineer Research and Development Center (ERDC) to advance US Army Corps of Engineers (USACE) dredging technology and dredged material placement practices. The focus is on beneficial use (BU) of dredged material (DM), hereafter BUDM, that results from USACE’s management of navigation channels and ports around the nation. The objective of the study was to identify the current challenges facing domestic dredging practices and develop ideas and specific steps to drive effective projects. Study themes included improving the efficiency, cost, and procurement practices of the dredging industry; driving technology modernization; and fostering greater competition to promote more innovative dredging operations. A companion technical note goes into further details of our study (Mohan et al. 2025).

10 Feb 2026

Sustainable Dredged Material Management on the Ohio and Kanawha Rivers to Achieve Multiple Benefits

Abstract: This technical report showcases the sustainable dredge material management practices by the US Army Corps of Engineers (USACE) on the Ohio and Kanawha Rivers. Over the years, USACE Huntington District (LRH) has continually adapted their navigation operations, dredge maintenance activities, and sediment beneficial use processes in response to changing local and regional hydrodynamic conditions, the results from monitoring, and proactive stakeholder engagement. This report highlights three project sites—Bonanza Bar and R. C. Byrd Locks and Dam on the Ohio River and Winfield Locks and Dam on the Kanawha River—that exemplify sustainable dredge practices consistent with Engineering With Nature® principles. By implementing these best practices, LRH has established a more sustainable dredging program that generates economic, environmental, and social benefits beyond the mere removal of sediment from the federal navigation channel. These innovative practices have successfully achieved multiple benefits while executing USACE’s navigation mission. The data and lessons learned from these projects can be applied to other riverine projects aiming to use sediment beneficially, enhance the development of USACE sustainable dredging practices, and inspire future projects.

9 Feb 2026

Ice-Resistant Breakwater Rock Sizing at Elim, Alaska

Abstract: The Elim Subsistence Harbor project requires breakwaters capable of withstanding wave action and sea ice forces in Norton Bay, Alaska. This study analyzed meteorological data, satellite imagery, and ice formation patterns to determine appropriate armor stone sizing based on ice forces for the proposed breakwaters. Analysis revealed that Elim experiences predominantly northerly winds during winter, with southwesterly components developing during the May–June breakup period. Offshore ice breakup occurs earlier at Elim (late March) than at Nome (late April). Using the Modified Stefan Equation calibrated with field measurements, end-of-season ice thickness near shore averages 1.4 m. Ice forces at Elim are expected to be less severe than at Nome because of wind patterns and directional constraints, with primary concerns limited to ice approaching from southwest directions during breakup. Using empirical evidence from Nome Harbor and physical model studies, we recommend a zoned armoring approach using 8-ton stone for toes and 4-ton stone on slopes in ice-exposed areas as minimum protection, or 8-ton stone throughout ice-exposed zones for enhanced durability. Relatively steep slopes (1.5H:1V to 2H:1V) should be maintained to encourage protective rubble ramp development during ice interactions.