Engineer Research and Development Center

Adaptive Covariance Tapering for Large Datasets and Application to Spatial Interpolation of Storm Surge

Press Operations — Tue, 11 Aug 2026 20:40:00 GMT

Abstract: Covariance tapering is a popular approach for accommodating computational efﬁciency for the application of Gaussian process -based spatial interpolation for large datasets. This is accomplished by introducing sparsity in the GP covariance matrix, through the introduction of a compactly supported taper function. The support of the taper function around each spatial node is deﬁned through the taper range variable. The latter is selected to achieve the desired degree of global sparsity in the covariance matrix, and deﬁnes the number of connected neighbors around each node. For problems with irregular nodal density, adaptive covariance tapering can be used to improve accuracy for the taper implementation. In this case, the taper ranges of the taper function have spatial variability, allowing uniform local sparsity to be achieved despite the data irregularities. The optimization of the taper ranges to accomplish this objective has a computational burden that is dependent on the size of the database, prohibiting its application to very large datasets. This paper formally considers the adoption of adaptive covariance tapers for such datasets. Though algorithmic developments are general, the problem is discussed for a speciﬁc application, the spatial interpolation of storm surge. For establishing computational efﬁciency in the optimization of the taper ranges we propose to utilize only a small subset of nodes, termed inducing points. An adaptive, iterative formulation is further developed to support the selection of the inducing points, shown to be critical for achieving the desired local sparsity for the remaining points. At each iteration, the taper range selection is performed using the current subset of inducing points, the achieved sparsity across all nodes is estimated, and then new inducing points are added within the sub-regions for which the discrepancy from the target local sparsity is the largest. The latter points are considered to have the highest expected utility as inducing points. Adding inducing points in close proximity is avoided through the inclusion of a clustering step. The implementation is demonstrated for interpolation of peak storm surge along the New Jersey coast, using two different domains, one with 64,379 nodes and one with 271,669 nodes.

Eight Recommendations to Enhance Biodiversity Outcomes of Nature-Based Solutions at Multiple Scales

Press Operations — Tue, 11 Aug 2026 20:38:00 GMT

Abstract: Ambitions to mainstream Nature-based Solutions (NbS) and achieve global implementation are hampered by the lack of transdisciplinary integration across disciplines and practice. Ecological knowledge, including an under-standing of how biodiversity can support, and be supported by, NbS design and implementation remains an under-studied component of the NbS concept despite its critical importance. Starting with a brief primer on the major roles that biodiversity plays in NbS performance, we present eight recommendations for enhancing biodiversity in NbS planning and implementation. This narrative expert synthesis draws from an interdisciplinary literature search and decades of experience across landscape ecology, environmental engineering, urban planning, wildlife management, ecological restoration, and conservation science. Recommendations emphasize the importance of considering the ecological mechanisms that support biodiversity (i.e., viable populations of coexisting species) and understanding the role of organismal life history, species interactions, habitat preferences, and metapopulation dynamics in determining NbS features’ ecological resilience and contributions to biodiversity enhancement (i.e., IUCN Global Standard Criterion 3). We also emphasize the importance of assessing biodiversity across spatial scales and dimensions (e.g., functional, phylogenetic) and monitoring and ecological management for anticipating and adapting to unexpected outcomes, invasive species, and ecosystem dis-services. This review is intended to increase connections between ecological science, conservation biology, and NbS implementation to support more biodiverse projects with more robust, resilient, and multifunctional performance and greater contributions to global conservation.

Continental-scale mapping of forest tree density in North America using remote sensing and deep learning with uncertainty quantification

Press Operations — Tue, 11 Aug 2026 15:57:00 GMT

Abstract: Accurate, spatially consistent estimates of tree density remain elusive at continental scales, limiting our ability to assess forest structure, carbon stocks, and biodiversity. Existing global assessments have relied on simpliﬁed statistical models and sparse, heterogeneous ground data that are insufﬁcient to capture nonlinear ecological interactions and spatial variability. To address these limitations, we integrated more than 600,000 harmonized ground-based forest inventory plots with satellite-derived vegetation indices, climate surfaces, soil properties, and topographic covariates to develop a deep learning framework for high-resolution mapping of tree density across North America. We evaluated four modeling approaches—generalized linear models, ridge regression, random forest, and a feedforward neural network. Among all models tested, the FFNN achieved the highest predictive accuracy, and was used to produce a wall-to-wall tree density map at 3 km resolution for the continent. We estimated that the total number of forest trees with diameter at breast height ≥ 10 cm across North America ranges from 339 to 514 billion, substantially lower than the widely cited estimate of 603 billion trees reported by Crowther et al. (2015). When smaller stems were included, totals more than doubled, reaching 738 billion to 1.12 trillion trees. We quantiﬁed uncertainty using Monte Carlo Dropout, generating pixel-level error estimates and conﬁdence intervals. Spatial patterns reveal high tree densities in boreal and temperate forests, intermediate densities in mixed broadleaf regions, and relatively low densities in deserts, Mediterranean systems, and tundra. Compared to the global GLM-based benchmark by Crowther et al. (2015), our deep learning framework achieves markedly higher predictive accuracy, aligns more closely with national forest inventory statistics, and provides explicit uncertainty quantiﬁcation, supporting applications in carbon accounting, biodiversity modeling, and ecosystem monitoring at scales through region speciﬁc calibration and validation.

AFM Analysis of Rejuvenated Graphene Nanoplatelets for Nanoscale Reinforcement and Microwave-Induced Healing in Asphalt Binders

Press Operations — Tue, 11 Aug 2026 15:54:00 GMT

Abstract: Understanding nanoscale mechanisms governing reinforcement and healing in asphalt binders is essential for developing durable pavements. This study investigates graphene nanoplatelets (GnP) and rejuvenator-infused graphene (GnP-Rej) in a PG 67–22 binder using PF-QNM atomic force microscopy under unaged, PAV-aged, and microwave-treated conditions. GnP reﬁned binder morphology, reducing surface roughness from ~2.1 nm to ~1.44 nm at 0.24 wt% and increasing stiffness through molecular conﬁnement, with saturation beyond ~0.1 wt% due to agglomeration. Aging increased peri- and para-phase modulus by ~68% and ~61%, respectively, while GnP and GnP-Rej mitigated these effects. GnP-Rej exhibited dual-function behavior, enhancing local compliance and interfacial mobility. Microwave activation increased adhesion by up to ~51% without signiﬁcant modulus change. The adhesion-based healing index conﬁrmed consistent nanoscale recovery, with maximum healing observed at 0.24 wt% GnP-Rej. These results indicate that healing is governed by adhesion-controlled nanoscale recovery and provide mechanistic insight into the relationship between nanoscale behavior and improved asphalt performance.

Geotechnical evaluation of overwash chenier beach deposits

Press Operations — Tue, 11 Aug 2026 15:52:00 GMT

Abstract: This study evaluates the long-term geotechnical effects of segmented breakwaters on shell-rich chenier deposits in southwestern Louisiana. The analysis integrates in-situ lightweight dynamic cone penetrometer (PANDA DCPT) proﬁles with multi-scale laboratory tests to compare a breakwater-protected (Hybrid) transect against an exposed (Natural) shoreline. Results indicate that the peak friction angle and maximum dilatancy of shell-hash occur at a site-speciﬁc optimal median grain size (D50) of approximately 1.0 mm, which geometrically coincides with the minimum void ratio. Shear strength inversely correlates with the coefﬁcient of uniformity (Cu). In ﬁner sediments with wider gradations (D50 < 1.0 mm), excess void ﬁllers act as a lubricant that facilitates particle rearrangement and lowers shear strength. Conversely, in coarser mixtures (D50 > 1.0 mm), strength is reduced not by lubrication, but due to a loose, highly porous skeleton lacking sufﬁcient contact points. At the ﬁeld scale, PANDA DCPT proﬁles revealed distinct differences between the two sites. The protected transect retained a thinner, geotechnically weaker shell layer, ranging from 0.2 to 0.8 m thick. In contrast, the exposed shoreline maintained a robust thickness of 0.4 to 1.0 m. Although breakwaters effectively attenuate incoming wave energy, they disrupt natural winnowing processes and trap poorly sorted ﬁner sediments. This hydrodynamic alteration shifts the soil fabric and introduces a coastal management trade-off. While breakwaters successfully limit short- term retreat, they produce a geotechnically weaker substrate that is susceptible to remobilization during future extreme wave events. Consequently, predictive morphodynamic models must dynamically refresh these coupled physical parameters to accurately assess the long-term resilience of engineered shorelines.

Establishing Native Submersed Aquatic Vegetation at Times Beach, Buffalo, New York

Press Operations — Tue, 11 Aug 2026 15:38:00 GMT

Purpose: Establishing native submersed aquatic vegetation (SAV) in reservoirs, lakes, and ponds involves several considerations, including sources and types of transplant propagules, fluctuating water levels, and herbivory (Smart et al. 1998). Over the past 20 years, US Army Engineer Research and Development Center (ERDC) Environmental Lab researchers have developed methods for establishing native SAV that address these issues. While consistently and successfully applied in the southern United States (Dick et al. 2005), their applicability to northern waterbodies remains untested. This two-part demonstration study evaluated several SAV establishment techniques in a constructed wetland adjacent to Lake Erie, Buffalo, New York.

Simulation now a fixture to optimize USACE navigation projects

By Tim Reeves, U.S. Army Engineer Research and Development Center — Wed, 05 Aug 2026 15:09:17 GMT

For years, the U.S. Army Watercraft and Ship Simulator — located at the U.S. Army Engineer Research and Development Center (ERDC) in Vicksburg, Mississippi — has served as an important resource for district engineers. Whether planning new inland waterways, designing deep-draft coastal channels, or enhancing existing structures, districts could leverage the simulator and its team.

ERDC-EL researchers join USACE New Orleans District-led Maurepas Swamp Project

Justus Reed, Public Affairs Specialist — Tue, 04 Aug 2026 19:27:52 GMT

A team of experts from ERDC-EL are supporting the New Orleans District in their River Reintroduction into Maurepas Swamp Project, an initiative that will divert freshwater from the Mississippi River back into the swamp through a 5.5-mile controlled-flow diversion and extend the swamp’s lifespan and habitat, providing benefit to approximately 45,000 acres within the swamp. The project aims to improve the cypress-tupelo swamp’s health by adding vital nutrients and flushing stagnant, low-oxygen water.

Tacoma Harbor Navigation Improvement Project: Ship Simulation Study

Press Operations — Tue, 04 Aug 2026 18:24:00 GMT

Abstract: The US Army Engineer Research and Development Center (ERDC), in collaboration with the US Army Corps of Engineers Seattle District, conducted a preengineering design (PED)–level ship simulation study. The study aimed to validate and finalize proposed modifications to the federally maintained waterways in the Blair Waterway in the Port of Tacoma, Washington, and to assess the potential effects of such modifications on navigation. The proposed designs incorporate recommendations from feasibility-level ship simulations that ERDC con-ducted by in 2019. The proposed modifications to the Port of Tacoma include channel deepening, realignment, widening, and enlargement of the Blair Waterway turning basin. Additionally, the study evaluated the potential effects of a beneficial use of dredged material site, referred to as East Commencement Habitat Opportunity (ECHO), which would be located near the entrance to the Hylebos Waterway.

Modeling Evaluation of a Bird Island Design in Hampton Roads, Virginia

Press Operations — Tue, 04 Aug 2026 18:22:00 GMT

Abstract: This report documents a numerical modeling investigation on the sediment transport and morphology changes surrounding designed marine habitats for seabirds in Hampton Roads, Virginia. It assembles and analyzes historical and newly collected wave and hydrodynamic data from the study area. The datasets are used to calibrate and validate coastal wave, hydrodynamic, and sediment transport models. It describes developments of model alternatives that correspond to different bird island designs. It evaluates current and sediment transport fields and seabed volume changes around the island under a representative normal year (2020) and under a storm simulation condition for a 50 yr return synthetic storm with corresponding sea level rise. Model simulations show weak current and sediment transport fields prior to the island construction. With alternative designs of the island, model results show significant changes in magnitudes and spatial distributions of current and sediment transport rate. Analysis of model bed volume changes demonstrates different erosion and deposition trends under the normal environment and under the storm simulation condition. The island design and configuration, including island orientation, island slopes, and material coverage, respond differently to the impact of physical forcing applied in the modeling.

Environmental Data Intelligence Ecosystem (EDIE):Software Requirements Specification (SRS) v1.0

Press Operations — Mon, 03 Aug 2026 18:11:00 GMT

Abstract: The objective of this report is to evaluate the software requirements necessary to define the minimal viable product supporting the Environmental Data Intelligence Ecosystem (EDIE) software suite. The EDIE is designed to aid alignment of Defense State Memorandum of Agreement systems with Formerly Used Defense Sites systems and any future Environmental Division software packages into one common environment. Further the EDIE application will consolidate access and authentication, at the system level, to align with necessary Single Sign On requirements. The EDIE systems will serve as a hub for common communication and information dissemination among Environmental tools and systems.

Customer Support Ticketing Analysis and Comparisons

Press Operations — Mon, 03 Aug 2026 18:09:00 GMT

Abstract: This report evaluates existing tools capable of satisfying the needs of our customer, whilst also identifying the possibilities of creating our own solution from scratch. As a vast majority of businesses use some form of information technology service management, many options already exist to solve this problem. We identify core values important to our customer and evaluate three different solutions and how they will support those values.

Mississippi Coastal Improvements Program (MsCIP) Barrier Island Restoration Long-Term Directional Wave, Circulation, and Water Level Analysis

Press Operations — Mon, 03 Aug 2026 18:06:00 GMT

Abstract: The Mississippi Sound barrier islands, including Ship Island, protect the Mississippi coast from wave-induced erosion during storms. Hurricane Camille (1969) breached Ship Island, and Hurricane Katrina (2005) widened the Camille Cut, increasing the mainland coast’s exposure to waves. To protect the coast, the US Army Corps of Engineers filled the cut with sand and restored Ship Island to its pre-Camille condition in 2020. To evaluate changes in wave height and potential changes in tides and residual currents, field observations via moorings and roving surveys were conducted pre- (2014–2016) and postrestoration (2022–2024). The tidal range and currents were found to be similar pre- and postrestoration, with slight decreases behind Ship Island. Behind and in front of Ship Is-land, the tidal ellipses shifted to being more shore parallel. The residual currents were primarily wind driven and showed little change in magnitude and direction around Ship Island during both summer and winter conditions. Waves passing through the Camille Cut were reduced, and the ratio of significant wave height behind to in front of Ship Island decreased from 0.40 to 0.25 following restoration. The Ship Island restoration reduced wave heights without significantly changing the tidal and residual currents in the Mississippi Sound.

An Innovative Approach of Vibration Testing of Concrete Structure Using Performance Based Evaluation Techniques

Press Operations — Mon, 03 Aug 2026 18:04:00 GMT

Abstract: Many of our nation’s critical water resource infrastructures have already surpassed their intended design lives. Therefore, there is a critical need to develop assessment procedures that will transform dam operations and stabilization mechanisms that can extend the service life of these vital structures. These actions are crucial for ensuring safe and secure public services. Performance-based testing using a cold gas thruster (CGT) is a new and innovative nondestructive testing technique that is being implemented to better assess critical infrastructure. The CGT is an instrument that delivers a high-magnitude, short-duration impulse load that produces an impulse response in the structure. Using these dynamic responses, the structure’s behavioral response and key performance indicators can be determined. Furthermore, a high-fidelity numerical model that accurately predicts behaviors can be developed with the use of these dynamic responses.

ERDC Concrete Expertise Helps Advance Montgomery Locks and Dam Modernization

Kaley Webb, public affairs specialist — Sat, 01 Aug 2026 20:53:18 GMT

The U.S. Army Engineer Research and Development Center (ERDC) recently supported a major step toward modernizing one of the Ohio River’s oldest navigation structures, successfully validating specialized mass and underwater concrete mixtures needed to construct a new 110-foot by 600-foot lock chamber at Montgomery Locks and Dam.

ERDC summer interns dive into research, community

Annette Kirklin, public affairs specialist — Thu, 30 Jul 2026 20:19:29 GMT

This summer, nearly 150 high-school, undergraduate and graduate students are working in Vicksburg, Mississippi, as interns at the U.S. Army Engineer Research and Development Center (ERDC).

Collaboration key to accelerating mission delivery across USACE environmental portfolios

Justus Reed, Public Affairs Specialist — Wed, 29 Jul 2026 14:39:23 GMT

The U.S. Army Engineer Research and Development Center (ERDC) is helping transform how the U.S. Army Corps of Engineers (USACE) approaches environmental cleanup. By delivering advanced science, technology, and engineering solutions, ERDC is actively working to accelerate remediation, reduce risk, and return contaminated sites to productive use.

ERDC-EL Director Dr. Edmond Russo retires after 30+ years of service

Justus Reed, Public Affairs Specialist — Mon, 27 Jul 2026 19:41:50 GMT

After more than three decades of service to the U.S. Army Corps of Engineers (USACE), Dr. Edmond Russo, director of the U.S. Army Engineer Research and Development Center’s (ERDC) Environmental Laboratory (EL), closed the book on his storied career.

Size, Weight, Power, and Cost (SWaP-C) Evaluation for Global Navigation Satellite System (GNSS) Receivers and Antennas

Press Operations — Mon, 27 Jul 2026 13:34:00 GMT

Abstract: The purpose of this technical note is to provide a brief assessment of Global Navigation Satellite System (GNSS) receivers and antennas, focused specifically on vertical positioning. The work compares multiple GNSS receivers at various cost points and antennas of different types during static testing against a known benchmark. Results show that high-cost GNSS receivers do provide better results than low-cost GNSS receivers, but there are likely use cases that the low-cost receiver should provide adequate results. The geodetic-survey GNSS-type antenna provide better results than the helical-style antennas, but similarly, there are use cases that justify usage of the smaller and lighter helical-style antennas.

Feasibility of a Photothermal Noncontact Dry Film Thickness Measurement Device for Automated Inspection of Department of Defense Coating Systems on Steel Substrates

Press Operations — Fri, 24 Jul 2026 13:32:00 GMT

Abstract: The quality and reliability of coatings for steel structures are critical to the longevity of the Department of Defense’s infrastructure. Coatings are the first line of defense against the environmental degradation of steel and require inspection. Nondestructive techniques (NDT) are commonly employed to assess a coating’s condition and inform maintenance decisions. This study sought to examine a photothermal (PT) noncontact NDT method to measure coating dry film thickness, with potential for robotic vehicle attachment. The performance of the noncontact method was com-pared to a trusted contact nondestructive method within a laboratory environment. This study evaluated the method’s accuracy, consistency, repeatability, and limitations. Results demonstrated the noncontact NDT method’s capabilities and limitations. The research highlights the challenges associated with implementing noncontact NDT for complex coating systems and informs future development efforts.