Development of a Trace Element Signature Library Across a Large Watershed for Assessing Large-Scale Fish Movement Patterns

Press Operations — Fri, 08 May 2026 20:30:00 GMT

Abstract: Using trace element or stable isotope analysis has proven to be an effective means to characterize early life history and large-scale movement patterns in fishes. Target species are assessed for analyte concentrations occurring in calcified hard structures and compared to signatures noted from associated watersheds. However, this approach assumes analyte absorption occurs in proportion to their availability, and success relies heavily on the ability to identify unique water chemistry signatures between neighboring watersheds within a defined study area. Our objective was to establish a trace element signature profile for major tributaries occurring within the Mississippi River Valley (MRV). Water samples were obtained from 49 stations and evaluated for the presence and relative concentration of Ba, Sr, Ca, Fe, and Li. Analyte concentrations (milligrams per liter) varied across the sampled stations, although Li occurred at only four stations, primarily in the upper reaches of the MRV, and provided little discriminatory use. Concentrations of Fe and Ca depicted an inverse relationship, with Ca having higher concentrations in the upper third of the MRV while Fe typically had higher concentrations in the lower third. Ratios of Ba:Ca and Sr:Ca (millimole per mole) exhibited the greatest utility for delineating river-specific or reach-specific signatures.

Little Rock District USACE breaks ground on $74 million F-35 academic training center at Ebbing Air National Guard Base

Tomas Rofkahr — Fri, 08 May 2026 20:15:55 GMT

The U.S. Army Corps of Engineers Little Rock District broke ground May 6 on a $74 million academic training center at Ebbing Air National Guard Base, advancing the base's transformation into a one-of-a-kind international F-35 pilot training facility.

James W. Trimble Lock and Dam: More than 50 years supporting navigation

Erin Jimenez — Fri, 08 May 2026 19:52:31 GMT

The James W. Trimble Lock and Dam is one of 18 navigation locks and dams that make up the McClellan-Kerr Arkansas River Navigation System. Authorized by Congress through the River and Harbor Act of 1946, the MKARNS was built to make the Arkansas River commercially navigable from the Mississippi River to the Port of Catoosa near Tulsa, Oklahoma.

U.S. Army Corps of Engineers to begin Ocean City dredging ahead of tourist season

Press Operations — Fri, 08 May 2026 19:07:00 GMT

The U.S. Army Corps of Engineers (USACE), Baltimore District, is scheduled to remove approximately 15,000 cubic yards of dredged material from the Ocean City Inlet beginning Friday, May 8, 2026.

USACE terminates Chickamauga Lock Chamber Contract

Press Operations — Fri, 08 May 2026 18:11:00 GMT

NASHVILLE, Tenn. (May 8, 2026) – The U.S. Army Corps of Engineers (USACE) Nashville District terminated the lock chamber contract with Shimmick Construction Company, Inc. (SCCI), at the Chickamauga Lock Replacement Project on the Tennessee River in Chattanooga, Tennessee, effective today. This decisive action is necessary to get the project back on track and protect taxpayer dollars.

Supporting the shores: How the U.S. Army Corps of Engineers partners with communities during high-water events

Avery Schneider — Fri, 08 May 2026 14:54:16 GMT

As spring brings rain and melting snow to the Great Lakes region, communities along Lake Ontario are once again navigating the challenges of rising water levels. During these high-water events, local municipalities, county emergency responders and state agencies are always the first line of defense, working tirelessly to protect neighborhoods and critical infrastructure. Behind the scenes, the U.S. Army Corps of Engineers serves as a vital federal partner. While the Corps of Engineers does not lead the initial emergency response, it stands ready to supplement the capabilities of local and state governments with specialized engineering expertise, historical data and critical flood-fighting supplies when the situation demands it.

USACE to demolish former French Quarter clubhouse to reach suspected contamination

Press Operations — Fri, 08 May 2026 14:00:00 GMT

The U.S. Army Corps of Engineers, St. Louis District, plans to demolish the former clubhouse at the closed French Quarter apartment complex in Hazelwood as part of ongoing cleanup efforts under the Formerly Utilized Sites Remedial Action Program (FUSRAP). USACE determined demolition is necessary to safely access and remediate contaminated material located directly beneath the structure and below the ground surface near the structure.

Road Closure over Red Rock Dam May 12-14

Press Operations — Thu, 07 May 2026 20:26:16 GMT

The U.S. Army Corps of Engineers, Rock Island District, announces a full road closure to Highway T15 across the Red Rock Dam May 12-14. The closure is necessary for the ongoing rehabilitation project on the Red Rock Dam gates.

Mobile District strengthens hurricane readiness through exercise

Pentagon News — Thu, 07 May 2026 19:04:09 GMT

With hurricane season approaching, the U.S. Army Corps of Engineers, Mobile District, is continuing to strengthen its hurricane preparedness efforts through a planned tabletop exercise designed to bring personnel and partners together ahead of the 2026 season.

Robust Error State Sage-Husa Adaptive Kalman Filter for UWB Localization

Press Operations — Thu, 07 May 2026 17:07:00 GMT

Abstract: Given the sensors’ path and interference mitigation capabilities, ultra-wideband (UWB)-based positioning systems have demonstrated high accuracy and reliability. This work aims to improve the Sage-Husa fuzzy adaptive filter (SHFAF) proposed in previous works by modifying the motion model to a 3-D ground-based differential drive robot using IMU and wheel encoder kinematic fused control inputs. In addition to the changed motion model kinematics, this article improved the positive definite constraint on P and R during dynamic estimations, thus making the filter more robust to outliers. An improvement to the computation and derivation of the fuzzy logic system for the SHFAF based on the adaptive neuro-fuzzy inference system (ANFIS) structure was developed, and training the fuzzy system using gradient descent was applied to improve the system’s accuracy. Experimental validation was conducted using real-world data from a Clearpath Jackal robot equipped with Qorvo UWB sensors and static nodes. Regarding localization accuracy, the proposed velocity-based SHFAF (VelSHFAF) system outperformed the previous SHFAF implementation by approximately 30%–25% across two test courses, demonstrating its enhanced performance and reliability.

Surface Oxide Removal in Preparation for Controlled Liquid Metal Embrittlement

Press Operations — Thu, 07 May 2026 17:05:00 GMT

Abstract: During liquid metal embrittlement a liquid metal inﬁltrates grain boundaries of a compatible solid metal, interrupting the inter-grain bonds and weakening the metal. Ongoing research has proposed that this effect may be used to perform additive/subtractive hybrid machining to fabricate replacement components, using relatively simple equipment and low material and instrument costs. The gallium/aluminum pairing is of particular interest due to the usage of aluminum in a wide variety of structural and aerospace applications coupled with gallium’s nontoxicity and melting point just above room temperature, which facilitates storage and transport. To activate aluminum to gallium inﬁltration, the surface oxide formed on aluminum in atmosphere must ﬁrst be removed simultaneously with a signiﬁcant amount of bulk metal to promote ﬂow control of the liquid metal. Three targeted techniques for oxide removal were tested and compared, speciﬁcally mechanical abrasion, chemical etching, and laser ablation. Mechanical abrasion is simple to implement but lower precision. Chemical etching requires signiﬁcant prep work and cleanup but could operate on entire sheets of substrate simultaneously with proper masking. Although laser ablation requires the most complex instrumentation, it requires minimal prep work and provides the greatest precision, making it ideal for the manufacturing application under development here.

Self Excited Hoisting Chain Tension Measurements for Dam Spillway Gates and Identification of Uneven Hoisting

Press Operations — Thu, 07 May 2026 17:01:00 GMT

Abstract: Tainter gates are critical components of inland navigation systems, as they regulate the flow of water through dams, enabling a navigable depth of waterway. A critical issue with Tainter gates arises when the gates are raised or lowered in a skewed, uneven fashion, which can cause redistribution of stresses and exacerbate fatigue damage. This uneven hoisting of the gate manifests itself as unequal tension in the chains that raise the gate. An opportunity to indirectly measure the tension in hoisting chains arose during field testing of a Tainter gate, where accelerometers were placed on easily accessible locations on the Tainter gate with the goal to perform a modal analysis of the gate. During operation, the hoisting chains of the tested gate would audibly pop, which was clearly identifiable in acceleration records and expected to be the response of the chains themselves, rather than the modal vibrations of the Tainter gate. To support the notion that the recorded vibrations represent the response of the chains, this paper explores the dynamics of the chains to develop the relationship between chain frequency and tension. The developed relationship is validated in a laboratory experiment of a chain cut from a Tainter gate where the natural frequency of the chain is measured for varying tension in the chain. The results of the study show that this approach can be used as a quick and inexpensive method to monitor for uneven hoisting on Tainter gates from easily accessible locations on the gate and with inexpensive sensors.

Quantifying the Role of Vegetation on Urban Heat over Bengaluru, India

Press Operations — Thu, 07 May 2026 16:59:00 GMT

Abstract: The urban heat island (UHI) effect refers to how cities tend to be warmer than their non-urban surroundings, which increases the risk for heat-related illnesses and amplifies energy demands. Therefore, developing UHI mitigation strategies is crucial. Bengaluru, India has been rapidly urbanizing, but has yet to receive attention regarding potential UHI mitigation strategies. This work uses the Weather Research and Forecasting model with the single-layer urban canopy model to determine how UHI intensity changes in Bengaluru with perturbations of −10%, + 10%, + 20%, and + 30% in vegetation amount since recent work has shown that vegetation amount is the leading control of urban heat in Bengaluru. These perturbations illustrate how much the UHI could be amplified by near-depletion of vegetation or mitigated via realistic increases in vegetation. The simulations were investigated diurnally and during the dry and wet seasons. Results show that increases in vegetation were associated with a decrease in urban land surface temperature, an increase in the latent heat flux, and decreases in the sensible heat flux, and vice versa for a decrease in vegetation. Significant changes in UHI intensity usually occurred only when vegetation was increased by 20% or more. However, for the dry season nighttime, which exhibited the highest UHI intensity in the control run (1.70oC), the 10% increase in vegetation produced a significant decrease of − 0.19oC in UHI intensity, likely due to a shallow planetary boundary layer height. These results could have implications for mitigating urban heat, and reducing energy demands and public health risk in Bengaluru.

Tribological Properties of Synthetic and Biosourced Lubricants Enhanced by Graphene and Its Derivatives: A Review

Press Operations — Thu, 07 May 2026 16:57:00 GMT

Abstract: This review explores the tribological properties of biosourced lubricants (biolubricants) enhanced by graphene (Gr) and its derivatives and hybrids. Friction and wear at mechanical interfaces are the primary causes of energy loss and machinery degradation, necessitating effective lubrication strategies. Traditional lubricants derived from mineral oils present environmental challenges, leading to an increased interest in biolubricants derived from plant oils and animal fats. Biolubricants offer high biodegradability, renewability, and low toxicity, positioning them as ecofriendly alternatives. This work extensively reviews the role of Gr-based nanoadditives in enhancing the lubrication properties of biolubricants. Gr with its exceptional physicomechanical properties has shown promise in reducing friction and wear. The review covers various Gr derivatives, including Gr oxide (GO) and reduced Gr oxide (r-GO), and their performance as lubrication additives. The discussion extends to Gr hybrids with metals, polymers, and other 2D materials, highlighting their synergistic effects on the tribological performance. The mechanisms through which these additives enhance lubrication, such as the formation of protective films and improved interactions between lubricants and tribopairs, are examined. Emphasis is placed on the environmental benefits and potential performance improvements of Gr-based biolubricants. Finally, by analyzing current research and technological trends, the paper outlines future prospects for optimizing lubricant formulations with Gr-based nanoadditives, aiming for more sustainable and efficient tribological applications.

An All-Hazards Return on Investment (ROI) Model to Evaluate U.S. Army Installation Resilient Strategies

Press Operations — Thu, 07 May 2026 16:55:00 GMT

Abstract: The paper describes our project to develop, verify, and deploy an All-Hazards Return of Investment (ROI) model for the U.S. Army Engineer Research and Development Center (ERDC) to provide army installations with a decision support tool for evaluating strategies to make existing installation facilities more resilient. The need for increased resilience to extreme weather caused by climate change was required by U.S. code and DoD guidance, as well as an army strategic plan that stipulated an ROI model to evaluate relevant resilient strategies. During the project, the ERDC integrated the University of Arkansas designed model into a new army installation planning tool and expanded the scope to evaluate resilient options from climate to all hazards. Our methodology included research on policy, data sources, resilient options, and analytical techniques, along with stakeholder interviews and weekly meetings with installation planning tool developers. The ROI model uses standard risk analysis and engineering economics terms and analyzes potential installation hazards and resilient strategies using data in the installation planning tool. The ROI model calculates the expected net present cost without the resilient strategy, the expected net present cost with the resilient strategy, and ROI for each resilient strategy. The minimum viable product ROI model was formulated mathematically, coded in Python, verified using hazard scenarios, and provided to the ERDC for implementation.

USACE Jacksonville awards contract for Venice Beach Shore Protection Project

Press Operations — Thu, 07 May 2026 15:34:17 GMT

The U.S. Army Corps of Engineers (USACE) Jacksonville District awarded a contract on April 13, 2026, to Weeks Marine of Covington, Louisiana, for the third periodic renourishment of the Venice Beach Hurricane and Storm Damage Reduction Project.

Corps of Engineers and city of Northfield, Minn., to sign agreement marking the beginning of an environmental water tower project

Press Operations — Thu, 07 May 2026 14:51:54 GMT

The U.S. Army Corps of Engineers, St. Paul District, and the city of Northfield, Minnesota, will sign a project partnership agreement for the design and construction of a new city water tower during a brief ceremony May 15.

MSG Carlos Espada completes 60-day SkillBridge internship with the Europe District

Hannah Mitchell — Thu, 07 May 2026 09:33:00 GMT

Contrary to popular belief, internships are not just for college students. The U.S. Army Corps of Engineers, Europe District recently hosted Master Sgt. Carlos Espada for a 60-day SkillBridge internship as a Contract Specialist. This is the latest of several SkillBridge interns the district has hosted over the years.

CNMI residents asked to sort storm-related debris for safe, efficient pickup

Press Operations — Thu, 07 May 2026 08:00:00 GMT

The U.S. Army Corps of Engineers (USACE), in coordination with FEMA and local CNMI partners, will

Water managers to hold meeting as Rogue River Basin faces historically dry year

Press Operations — Wed, 06 May 2026 18:41:00 GMT

Water managers will hold two public information sessions May 18 to discuss historically low water levels in the Rogue River Basin. The experts from the U.S. Army Corps of Engineers (USACE) said the basin is currently on track for one of its worst years on record for water scarcity. Low rainfall and snowpack have created drought conditions for Lost Creek and Applegate lakes, creating challenges for refilling the basin’s two reservoirs ahead of the summer recreation season.