Engineer Research and Development Center News Releases

The Use of Nitrocellulose Production Waste for Energy Generation

Press Operations — Tue, 03 Mar 2026 21:18:00 GMT

Abstract: The US Army Engineer Research and Development Center investigated the use of nitrocellulose (NC) fines, an ammunition waste, for energy generation. NC is a natural high polymer obtained from treating cotton or wool with nitric and sulfuric acid. It is widely used in the industry, with military applications being the largest use currently. Since military applications range from bullet propellants to missiles for tube munitions, large quantities must be produced to meet the demand. However, large NC production batches result in large quantities of NC fines waste, generated in the form of insoluble fibers in suspension in wastewater after manufacturing. Hence, a method to reuse this generated waste and convert it into energy was tested. This study evaluated the potential of creating energy from NC waste through hydrothermal liquefaction and gasification of NC, yielding methane (CH4) as the final product. Results demonstrated that the CH4 concentrations increased as the temperature, reaction time, and catalyst addition were increased, yielding a maximum concentration of 2,000 ppm (6,400 peak area of the chromatograph). The homogenous catalyst performed better than the heterogenous catalyst, since it increased the CH4 yield up to 6 times the concentration obtained with no catalyst added.

Overview of PFAS in Aquatic Environments

Press Operations — Tue, 03 Mar 2026 21:16:00 GMT

Abstract: PFAS are highly stable fluorinated compounds with unique properties and are used in a broad array of industrial processes and commercial products. PFAS are extremely recalcitrant and are widespread in the environment, with measurable concentrations in soils, sediments, groundwater, surface water, and rainwater, even at sites far removed from known sources or releases. Select PFAS (especially longer-chain perfluorinated carboxylic and sulfonic acids) are known to bioaccumulate in aquatic food webs, presenting potential risk to higher trophic species, including hu-mans. Evidence suggests sediment serves as a repository and potential ongoing source for many of these long-chain PFAS. The global presence and persistence of PFAS pose a fundamental challenge to addressing potential effects on environmental quality and health. The public and policymakers are increasingly concerned about the potential presence and effects of PFAS in water and sediments. This concern includes knowledge gaps for dredged material management, posing challenges to execution of the US Army Corps of Engineers Civil Works navigation program. This document provides a comprehensive review of PFAS in the aquatic environment based on published studies and includes overviews of chemical classifications, regulatory considerations, historical uses and sources, environmental distribution, fate and transport pathways, and uptake and effects in aquatic organisms.

Demonstration Validation of Industrial Supercritical Water Oxidation (iSCWO) PFAS Destruction Technology: Aqueous Film-Forming Foam Treatment by General Atomics (GA) iSCWO System

Press Operations — Fri, 20 Feb 2026 21:45:00 GMT

Abstract: The Department of Defense (DoD) is confronted with a pressing environmental challenge concerning legacy aqueous film-forming foam (AFFF) concentrate, historically used in firefighting activities. Legacy AFFF contains PFAS, which are identified as persistent environmental contaminants associated with adverse health effects. Considering increasing environmental regulations and concerns regarding human health impacts, the DoD needs to properly destroy legacy AFFF. The US Army Engineer Research and Development Center (ERDC) led a project focused on the demonstration and validation of technologies for the destruction of PFAS in AFFF. Results are presented for the treatment of 100 gal. of AFFF using the General Atomics industrial Supercritical Water Oxidation system. The demonstration showed destruction removal efficiencies (DREs) for total PFAS analyzed via total oxidizable precursor (TOP) assay (S24 PFAS), ranging from 98.5% to 99.9991%. No volatile fluorinated compounds were detected in the stack emissions as analyzed via Other Test Method 50; however, up to 6,000 ppt S51 PFAS as analyzed via TOP assay was detected in demister effluent. The energy consumed per cubic meter of AFFF and order of magnitude S24 PFAS destroyed ranged from 2 to 24 MWh, while the energy consumed per gram of S24 PFAS destroyed ranged from 0.046 to 48 MWh.

Infection Risk Assessment for Socially Structured Population Using Stochastic Microexposure Model

Press Operations — Wed, 18 Feb 2026 21:53:00 GMT

Abstract: Predicting infection outbreak dynamics within local microenvironments is a challenging task. Some methods assume smaller population pools and often lack the statistical power of inferences. Others are designed for larger population pools and cannot be downscaled to accommodate the details of microenvironments. Practicable infection risk assessment models should account for population size, geometry and occupancy of public places, behavioral and professional patterns of daily routines, and societal structure. This study is based on the stochastic microexposure model, which has been generalized to describe clustered populations. The methodology is demonstrated for a community of several thousand students on campus. The results indicate the social structure has the ﬁrst order effect on the spread of the infection. Depending on the number, size, and degree of inner- and outer-cluster connections, the outbreak exhibits distinct durations, power, and multiple peaks of infection. Moreover, the contribution of different microenvironments to infection risk evolves during the course of the outbreak. Social structure plays a major role in infection spread and should be accounted for in risk prediction tools. The stochastic microexposure model accounts for the social structure of a population at multiple scales and can predict the dynamic contributions of different microenvironments to infection spread risks.

Civil Works Megaprojects: Cognitive Biases and Lessons for Effective Risk Mitigation

Press Operations — Wed, 18 Feb 2026 13:52:00 GMT

Abstract: U.S. Army Corps of Engineers (USACE) megaprojects are critical infrastructure investments that often experience cost overruns, schedule delays, and performance issues, with over 35 % of USACE dam structures rated in poor condition. This paper presents the ﬁrst quantitative case study of past USACE Lock and Dam megaprojects—including the Charleroi, Chickamauga, Olmsted, Soo, and Montgomery projects —to identify patterns of risk mismanagement that contribute to these challenges. Using Bayesian methods and quantitative analysis on the risk registers of these projects, the study demonstrates that over-optimism in initial risk assessments, particularly the underestimation of risk likelihoods, can diminish the effectiveness of subsequent mitigation efforts by 25 % on average. The analysis also ﬁnds that risk managers tend to prioritize mitigation for risks where their conﬁdence in assessment is highest, leaving higher-uncertainty risks less addressed. Based on these ﬁndings, the paper offers evidence-based recommendations for implementing structured risk governance frameworks, such as reference-class forecasting and external risk validation. This study advances project management knowledge by providing the ﬁrst quantitative evidence of cognitive biases shaping risk register practices in civil works megaprojects. Incorporating such insights into future risk assessment and decision support methods can support critical infrastructure management and performance.

Evaluating Freshwater Mussel Sampling Methodologies Using a Simulation Model

Press Operations — Fri, 13 Feb 2026 19:35:00 GMT

Abstract: Field surveys form the basis of many research efforts and are the foundation for estimates of population size and density that inform conservation and management practices for imperiled species. As a result, evaluating the performance of different survey methods across a range of conditions that may be encountered in the ﬁeld can increase understanding of the time and effort that may be required to ensure that survey results are sufﬁciently accurate and reliable for conservation goals. We used a spatially explicit agent-based model to simulate four commonly used freshwater mussel ﬁeld survey methodologies: simple random sampling (SRS), transect random sampling (TRS), adaptive cluster sampling (ACS), and qualitative timed searches (QTS) to investigate the inﬂuence of sampling method, spatial distribution, and mussel density on the performance (i.e., accuracy, precision, and detection rate) of survey techniques. Our analysis suggests that mussel density, spatial distribution, and sampling effort inﬂuence sampling accuracy, precision, and species detection for all sampling methods. QTS produces highly variable catch-per-unit-effort (CPUE) metrics when mussels are dense and/or clustered, indicating the technique may be unreliable as a proxy for density. Quantitative methods like SRS and TRS may be well-suited for estimating population characteristics, but a high level of effort may be needed to obtain reasonable accuracy when mussels occur at low densities. ACS may be more efﬁcient for mussels at low densities, but it can be challenging to plan for the level of effort required to complete an ACS protocol. Designing an ecological survey requires careful consideration of research objectives and available resources. Future research may consider the performance of qualitative and quantitative surveys in combination as a means of overcoming some of the practical challenges of applying individual survey methods.

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)

Press Operations — Thu, 12 Feb 2026 19:50:00 GMT

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.

Growth Patterns of Three Hydrilla Verticillata Biotypes in the United States

Press Operations — Thu, 12 Feb 2026 17:33:00 GMT

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.

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

Press Operations — Wed, 11 Feb 2026 17:30:00 GMT

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.

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

Press Operations — Wed, 11 Feb 2026 17:26:00 GMT

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.

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

Press Operations — Tue, 10 Feb 2026 13:48:00 GMT

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).

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

Press Operations — Tue, 10 Feb 2026 13:45:00 GMT

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.

Optimization of Refueling Infrastructure Locations for Freight Vehicles

Press Operations — Mon, 09 Feb 2026 15:14:00 GMT

Abstract: In both the public and private sectors, there is a drive to implement zero-emission solutions in traditionally polluting industries to limit their damaging environmental impact. The state of California, in particular, has implemented new legislation requiring higher percentages of freight trucks and commercial ﬂeets to be zero- emission vehicles starting in 2024. However, the lack of medium- and heavy-duty refueling stations across California hinders the transition to zero-emission freight. Selecting the locations for such future stations must balance demand distribution, monetary costs, land resources, stakeholder feedback, and the potential for disruptions from natural disasters, cyber interference and socio-economic shocks and stressors. We solve this logistics problem near-optimally by minimizing travel time while accounting for additional variables using a generalized inexact k-medoids method. This approach is relatively fast and scales computationally such that it can be applied on a statewide scale. We propose a near-optimized network of zero-emission stations across the state of California. Our network establishes a mean travel time from a location where a driver is expending fuel to a refueling station of six minutes and minimizes diversions from existing freight routes. In this way, our facility location model can hasten the conversion from a traditional to a clean freight industry in California and can be scaled up to a national level. While facilitating the reduction of emissions from freight infrastructure, our methodology also has the ﬂexibility to incorporate a variety of stakeholder values.

Upscaling Nature-Based Solutions for Reducing Risk from Natural Hazards: From Process to Practice

Press Operations — Thu, 05 Feb 2026 20:51:00 GMT

Abstract: Nature-based solutions (NbS) offer an innovative approach to reducing risks from natural hazards, aligning ecological processes with engineering objectives. However, successfully scaling NbS from site-speciﬁc interventions to systems-level applications remains a challenge. This paper examines an Engineering With Nature® (EWN®) case study to explore how NbS can be integrated into broader, systems-based engineering practices, demonstrating the transition from conceptual design to wide-scale, regional implementation. One such case study is Deer Island, located off the coast of Mississippi, USA, where EWN approaches stabilized shorelines and restored critical habitats. The project utilized natural sediment transport processes to rebuild marsh and dune systems, enhancing the island’s resilience to storm surges and erosion. Through careful integration of natural and engineered systems, Deer Island serves as a model for how NbS can mitigate risks at both local and regional scales, increasing the ability to recover from a natural disaster and overall ecological health. In particular, the case study highlights the beneﬁt of designing for multiple integrated ecosystem components to deliver a diverse array of ecological functions, goods, and services. The paper further underscores the importance of interdisciplinary collaboration, highlighting the role of landscape architects in creating multifunctional designs that incorporate natural features and processes. These designs enhance ecosystem services while addressing societal needs, providing a blueprint for how when combined landscape architecture, science, and engineering can synergize in NbS projects. By synthesizing lessons from the EWN and emphasizing the need for cross-sector collaboration, this paper outlines pathways to scale NbS from localized efforts to comprehensive strategies that reduce coastal storm risk.

A Systematic Review of Literature Utilizing Residential Smart Meter Data

Press Operations — Tue, 03 Feb 2026 19:31:00 GMT

Abstract: The global transition from traditional to advanced metering infrastructure (AMI) has led to an exponential increase in residential electricity consumption data collected through smart meters. Research themes and methodologies developed to analyze these data are driven largely by characteristics of smart meter datasets, such as the temporal resolution of data, the spatial and temporal extent of the dataset, and number of households included. However, these trends in the smart meter literature have not been comprehensively reviewed. Here, we present a systematic review of 268 studies analyzing smart meter data, published up to May 1, 2024, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework. Our findings reveal that cur-rent research is heavily reliant on a few open datasets, predominantly from high-income countries (e.g., the Customer Behavior Trials in Ireland and Low Carbon London in the UK), with approximately 90 % of studies utilizing data from developed countries. Although existing research highlights the potential of smart meter data to support a more sustainable and reliable electricity grid, especially in the face of rising demand and climate change, limited access to diverse data sources has constrained the inclusion of different geographic, climatic, and cultural contexts. Broader access to smart meter datasets is essential to expand research scope and generate insights applicable across different geographic and socio-economic settings; however, wider access also needs to be accompanied by well-designed privacy protections.

Estimating Component Probability of Failure at USACE Civil Works Facilities for Asset Management

Press Operations — Fri, 30 Jan 2026 21:44:00 GMT

Abstract: Infrastructure components are the building blocks of US Army Corps of Engineers (USACE) facilities such as navigation locks and dams. Estimates of component probability of failure are needed to support risk-informed decisions about managing and maintaining these systems and their components. At Inland Navigation (INAV) facilities, the models and methods currently in use are based on an expert elicitation. There is a need for more objective estimates of component probability of failure derived from data using statistical models and methods. This report demonstrates these models and methods and describes what kinds of data would be needed to put them into practice. The major impediment to putting these models and methods into practice is a lack of data on the age, performance, and other characteristics of in-service components. It will take time to develop these data. In the meantime, this report describes how these statistical methods and models can be adapted for use with operational condition assessment (OCA) ratings, which USACE maintains in an existing database at the enterprise scale. Finally, this report describes an analytical approach to criticality assessment, which is a systematic process for identifying which components, if failed, would lead to significant operational disruptions.

Guideposts and Guardrails for Biodiversity Accounting in the 21st Century

Press Operations — Thu, 22 Jan 2026 16:55:00 GMT

Abstract: The new Kunming-Montreal Post-2020 Global Biodiversity Framework (GBF) calls for transformative change to integrate biodiversity and conservation goals into decision-making across public and private sectors. As a result, biodiversity accounting approaches, which reduce the multifaceted complexity of nature to quantitative metrics for practical applications, are proliferating rapidly. These approaches will be essential for implementing growing practices like nature-based solutions, corporate biodiversity stewardship, no net loss policies, and sustainable infrastructure development. In this perspectives article, we identify ten considerations for biodiversity accounting to ground ongoing discourse in sound ecological science and to better integrate biodiversity into societal decision-making. These considerations pertain to three processes within biodiversity accounting: (1) selecting biodiversity targets, facets, indicators, and metrics, (2) tool and framework design, and (3) implementation. For each consideration, we highlight desirable attributes or practices, which we call “guideposts”, and cautionary notes demarcating problems to be avoided, or “guardrails”. These help to delineate the safe design space for creators and users of biodiversity accounting systems to avoid unintended consequences and reduce risks of failing to achieve conservation objectives via misuse or ineffective approaches. Major considerations include the need for careful disclosure of effort and statistical uncertainty, interoperability and ﬂexibility of frameworks, careful justiﬁcation and explanation of selected facets, metrics, and indicators, and attention to local social and ecological context. Consideration of these guideposts and guardrails could help avoid unintended consequences like accelerated biodiversity loss and exacerbated environmental injustice while providing a practical basis for achieving the sustainable futures envisioned in the GBF.

Assessing Longer-Term Effectiveness of Forest Management Guidelines on Breeding Habitat for Cerulean Warblers

Press Operations — Thu, 22 Jan 2026 16:42:00 GMT

Abstract: Widespread clear-cutting in the late 19th and early 20th centuries and subsequent regrowth has resulted in homogenous, closed-canopy forest structure across much of eastern deciduous forests in temperate North America. Forest management prescriptions designed to diversify stand structure have been increasingly applied with the goal of improving breeding habitat for declining species that require heterogenous forest structure, including Cerulean Warblers (“ceruleans”; Setophaga cerulea). Although a few studies have documented positive short-term (1–4 years post-treatment) responses of ceruleans to forest management prescriptions in the Appalachian Mountains region, longer-term responses have yet to be assessed. In 2019–2020, we followed the same spot-mapping methods as used previously (2005–2006 pre-harvest and 2007–2010 post-harvest) and compared territory density with previous estimates at each of 4 treatment levels (reduced basal area and overstory canopy by 0–75 %) across four forest stands on study sites in Tennessee, Kentucky and Ohio (n = 12 stands total) that had exhibited short-term positive density responses. Ceruleans did not exhibit consistently positive longer-term responses compared with pre-treatment densities when all stands were analyzed together. Compared with pre- treatment surveys, after 13–14 years post-harvest we documented density decreases of 1.0–3.1 territories per 10 ha at 5/9 stands, and positive responses of 1.8–2.2 territories per 10 ha at 3/9 treated stands. Over this period, midstory cover changed signiﬁcantly (increased) during the 10 years since these stands were last surveyed. Thus, sustaining the short-term (1–4 year) positive response of cerulean warbler territory density to timber harvest may require periodic follow-up treatments that reduce the development of a dense midstory; we recommend that this hypothesis, along with the methods to achieve these conditions, should be tested.

Exopolysaccharides from Rhizobium Tropici Modiﬁed the Surface Characteristics of a Mississippi River Levee Soil Clay and its Bulk Soil Properties

Press Operations — Thu, 22 Jan 2026 16:22:00 GMT

Abstract: Global climate change has led to the increased frequency of extreme ﬂooding events and heightened the vulnerability of river levees to ﬂood related damage. One promising approach to enhancing the sustainability of levee stabilization is the use of eco-friendly, biologically produced soil additives as alternatives to conventional materials for erosion control. This study investigates the effects of exopolysaccharides (EPS) produced by Rhizobium tropici on the physical and engineering properties of clayey soil from a Mississippi River levee. Speciﬁcally, the study examines how EPS affects particle size, surface charge, surface area, and key bulk soil properties, including Atterberg limits, compaction behavior, and hydraulic conductivity. Soil samples were collected from a levee embankment located in south of Vidalia LA, an area historically prone to slough slides due to highly plastic nature of its ﬂoodplain clay soils. X-ray Power Diffraction was used to characterize the mineralogy of soil clay, EPS and EPS-clay composites. Particle size distribution and Zeta potentials measurements were performed on EPS and EPS-amended clays. Engineering test included Atterberg limit determinations (liquid and plastic limits) and standard compaction tests. The addition of EPS signiﬁcantly increased the aggregate particle sizes of the levee clay through formation of EPS-clay composites. A strong correlation was observed between mean particle sizes and zeta potential in the composites. EPS also increased the liquid limit and plasticity of the soil while signiﬁcantly reducing its hydraulic conductivity. Overall, EPS-amended soil demonstrated improved resistance to seepage and erosion, indicating that EPS has the potential to enhance levee soil stability and contribute to more sustainable ﬂood control infrastructure.

Supporting Urban Sustainability Through Resilient Rail Transit Systems

Press Operations — Wed, 21 Jan 2026 18:59:00 GMT

Abstract: Urban rail transit is vital to supporting urban sustainability across environmental, economic, and social pillars. However, recent extreme weather events, particular ﬂooding, have increasingly disrupted its operations, high-lighting the urgent need to strengthen system resilience. Developing comprehensive resilience assessment methods with results of practical relevance is essential for evaluating the system’s capacity to withstand and recover from such disruptions, using quantiﬁable impacts across physical, operational, social, and economic dimensions. While resilience and sustainability are often discussed together in the context of climate change, methodologies for integrating sustainability considerations into resilience assessments to develop informed adaptation strategies remain underdeveloped. Drawing on the UN Sustainable Development Goals, this commentary examines the relationship between resilience and sustainability in the urban rail transit sector under disruptions related to natural disasters and climate change. Following this, it proposes a three-tier network modelling roadmap for assessing the resilience of urban rail transit, illustrating how sustainability concerns can be incorporated into resilience planning. This roadmap progresses from current mainstream topology-based approaches to a state-of-the-art performance-oriented method, and ultimately to a forward-looking vision that integrates socio-demographic considerations and prioritises equity. Positioned at the infrastructure-disaster- society nexus, this commentary advocates embedding a systemic view in transport network modelling to yield actionable resilience strategies that address extreme weather events while promoting urban sustainability.