23 Mar 2026

Assessment of Aluminum-Based Drinking Water Treatment Residuals from Multiple Utilities in the United States as Green Sorbents for PFAS

Abstract: Per- and polyfluoroalkyl substances are persistent environmental contaminants causing human health concerns. In this study, five aluminum-based drinking water treatment residuals were evaluated as green adsorbents for the removal of perfluorooctanoic acid and perfluorooctanesulfonic acid from water. Al-WTRs are nonhazardous solid wastes generated during the coagulation process of water treatment using aluminum salts or polymers. Although high PFAS adsorption capacity of Al-WTRs generated in one facility in the US has been reported, no study exists assessing PFAS adsorption capabilities of WTRs generated in multiple facilities using various types of aluminum coagulants. Batch adsorption experiments of PFOA and PFOS on Al-WTRs showed removal efficiencies exceeding 70 % for PFOA and 94 % for PFOS across all Al-WTRs. Maximum adsorption capacities for PFOS were significantly higher than those for PFOA, indicating the stronger affinity of the Al-WTRs for PFOS. Low desorption rates for both PFOA and PFOS suggested irreversible adsorption. Correlation analysis revealed that oxalate-extractable Al, Fe, and organic matter primarily contributed to PFOA adsorption, while pore size, oxalate-extractable Al, Fe, and total calcium primarily contributed to PFOS adsorption. These easily measurable parameters could be used as predictors when utilizing Al-WTRs as sustainable sorbents for PFAS removal. This study not only establishes the comparative and predictive performance of Al-WTRs from multiple utilities for PFAS sorption but also demonstrates their recycling potential within a circular-economy framework.

23 Mar 2026

Seamless Nearshore Topo-Bathymetry Reconstruction from Lidar Scanners: A Proof-of-Concept Based on a Dedicated Field Experiment at Duck, NC

Abstract: Accurate observations of the nearshore bathymetry, including within the breaking wave region, are critical for the prediction of coastal hazards, and improved understanding of sandy beach morphological response to storms. We implement the recent Boussinesq theory-based depth inversion methodology of Martins et al. (2023) to single- and multibeam lidar datasets collected during a dedicated field experiment on a sandy Atlantic Ocean beach near Duck, North Carolina. Compared with common approaches based on passive remote sensing technology, lidar scanners present several key advantages, including the capacity to directly measure the beach topography, waveforms and the cross-shore variations in mean water levels due to wave action, leading to the seamless reconstruction of a vertically-referenced beach topo-bathymetry. Given the potentially gappy nature of lidar data, particular attention is paid to the robust computation of surface elevation spectral and bispectral quantities, which are at the base of the proposed non-linear depth inversion methodology. Promising results on the final topo/bathymetry are obtained under contrasting wave conditions in terms of non-linearity and peak period, with an overall root-mean square error below 0.3 m obtained along a cross-shore transect covering both shoaling and breaking wave conditions. The accuracy of the final bathymetry in the shoaling and outer surf regions is generally found to be excellent, with similar skills as previously obtained in laboratory settings. Under the most energetic conditions, an underestimation of the wave phase velocity spectra is observed within the surf zone with all theoretical frameworks, potentially owing to surf zone vortical motions not yet accounted for in the present methodology. This underestimation of the wave phase velocities results in a relatively large overestimation of the mean water depth, between 30% to 100% depending on the theoretical framework. With the methodology described herein, lidars bring new perspectives for seamlessly mapping the nearshore topo/bathymetry, and its temporal evolution across a wide range of scales. Although currently limited to a single cross-shore transect, we believe that opportunities exist to integrate multiple remote sensors, which could address individual sensor limitations, such as coverage or the incapacity to directly measure waveforms.

19 Mar 2026

Compressed Snow Blocks: A Proof-of-Concept Study for Adapting Earth Block Technology for Cold Regions

Abstract: Snow construction plays a crucial role in military operations in cold regions, providing tactical fortifications, thermal insulation, and emergency infrastructure in environments where conventional building materials are scarce or require extensive infrastructure to support. Research into optimized snow compaction techniques has informed the design of snow-based protective structures, runways, and shelters. This study tested whether a conventional compressed earth block (CEB) machine could be used to produce compressed snow blocks (CSBs) suitable for construction applications in cold environments. The machine successfully formed CSBs with relatively consistent dimensions (i.e., block height), demonstrating feasibility and reliability in shaping snow for structural purposes. Density measurements of the snow blocks were more consistent with ice, indicating potential viability in load-bearing applications, but suggesting that the pressure applied during production may not be necessary to reach sufficient block strength depending on its intended end-use. While mechanical strength was not assessed, these initial findings support further investigation into optimizing this new snow compaction technique, the material properties, and block durability under environmental stressors (e.g., temperature fluctuations). Additional testing and development are required to refine this approach for faster, more efficient snow compaction for sustainable construction in cold regions.

19 Mar 2026

Arctic and Subarctic Zonal Characterization and Operational Thresholding (AZCOT)

Abstract: The US military develops and updates environmental parameters specified for the sustainment of operations throughout the world. These requirements are generally based on environmental data providing a baseline of temperature, wind, and precipitation expectations for each location. Observational data for Arctic regions is limited because of the remote and sparsely occupied geographical conditions. To address the need for updating these requirements, a 30-year analysis of meteorological conditions was conducted using a European Centre for Medium-Range Weather Forecasts (ECMWF) global reanalysis dataset over the Arctic and Subarctic region, defined by latitude 60°–90° North for this project. Raw hourly datasets were acquired, and the minimum temperatures, maximum wind speeds, maximum snow depths, and averages were determined over the period 1991–2020 between the months of October and March for each parameter. These were then visualized with geospatial analysis, producing a variety of maps designed to assist with the classification of parameters in Arctic zones of operation across a range of temporal resolutions. Finally, a review of operational limits for military equipment was conducted to match northern zones of operation with suitable capabilities dependent on environmental conditions.

18 Mar 2026

An Updated Irwin Sensor for Measurement of Surface Shear Velocity

Abstract: Accurate and efficient collection of field data related to aeolian processes is critical for improving wind erosion predictions and related management decisions. The Irwin sensor has been used in numerous wind tunnel and field studies to indicate surface shear velocity. However, the sensitivity of the sensor makes them difficult to maintain in a range of environmental conditions. This study presents a new generation of Irwin sensor incorporating updated electronics, battery operation, wireless data transmission, and streamlined field deployment and removal. A total of 20 sensors were manufactured and calibrated in a wind tunnel at the Engineer Research and Development Center. A subset of the sensors was calibrated using a PI-SWERL, which confirmed the two calibration methods converge on similar values for flat smooth test surfaces. The updated sensors were installed around a mesquite shrub at the Jornada Experimental Range, New Mexico, USA from February to July 2023. We found that initial data from the sensors accurately captured spatial patterns of surface shear velocity surrounding the shrub. The improvements to the sensor reduced workload for both deployment and maintenance, and reduced disturbance at the field site. We discuss potential opportunities to use the improved sensor network in a range of geomorphological research areas including quantifying aeolian sediment transport, building and parameterizing wind erosion models that incorporate spatial dependencies, and improving predictive tools for landform change.

17 Mar 2026

Estimating the Value of Virtual Aids to Navigation (VATONs) Deployed by the USACE LOMA Program near Lake Providence, Louisiana

Abstract: The purpose of this US Army Engineer Research and Development Center (ERDC) technical note (TN) is to estimate the value of a Virtual Aid to Navigation (VATON) as deployed from a mobile trailer by the Lock Operations Management Application (LOMA) program, operated through the ERDC Coastal and Hydraulics Laboratory (CHL). Estimates are developed based on the observed vessel traffic that transited the waterway during VATON deployment, historical information about vessel cargo movements and cargo value, and a mobile trailer cost estimate of $50,000.

13 Mar 2026

John H. Overton Lock and Dam, Red River: Lower Navigation Approach Physical Model

Abstract: The US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory (ERDC-CHL) conducted a physical model study of the John H. Overton Lock and Dam to optimize the navigation conditions in the lower lock approach. ERDC built a 1:100 Froude scale model to evaluate the navigation conditions for tows entering and exiting the lower lock approach. The final design consisted of two submerged rock dikes implemented approximately 1,500 and 3,000 ft downstream of the dam’s crest. The larger submerged rock dike was parallel to the channel, located in a scoured area at the downstream end of the riprap channel bed, and contained a crest elevation of approximately 15 ft, North American Vertical Datum of 1988 (NAVD 88). The smaller submerged rock dike extended from the most upstream end of the first rock dike, diagonally crossing the channel to the right-descending bank, and contained a crest elevation of approximately 30 ft, NAVD 88. The model provided data regarding tow tracks, current direction, and velocity information for various possible optimizations to the dam’s lower lock approach.

3 Mar 2026

Enhanced Spatial Resolution of Landsat Imagery Through Systematic Sensor Offset Exploitation: A Blended Pansharpening Approach

Purpose: This technical note presents a novel blended pansharpening methodology that exploits the systematic 7.5-meter (m) geometric offset between Landsat multispectral (MS) and panchromatic (pan) sensors to achieve selective spatial enhancement beyond conventional 15 m resolution limits. The approach creates a variable resolution product with an effective resolution of approximately 11.25 m and demonstrates superior spatial detail preservation in urban infrastructure while maintaining perfect spectral integrity.

3 Mar 2026

Overview of PFAS in Aquatic Environments

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.

25 Feb 2026

AIS Analysis of Waterway Utilization Based on Vessel Type and Class

Abstract: The purpose of this technical note (TN) is to provide an overview of a method used to classify waterway segments based on remotely-sensed vessel traffic on those waterway segments. Vessel traffic was evaluated using data from Automatic Identification System (AIS) broadcasts, which originate at transceivers onboard vessels and can be received by terrestrial shore sites or satellites. AIS is used by most ocean-going commercial vessels, while use by inland vessels varies according to domestic regulations.