11 Jun 2025

A Bellwether for Microplastic in Wetland Catchments in the Great Lakes Region

Abstract: This study is intended as a bellwether for the occurrence of microplastics (MPs) in Great Lakes wetlands. In 2020, sediment, surface water, and atmospheric deposition samples were collected from wetland catchments in or near five National Wildlife Refuges (NWRs) in the Great Lakes region: Horicon-WI, Seney-MI, Shiawassee-MI, Ottawa- OH, and Montezuma-NY. Sediment and surface water samples were taken from river, stream, and canal inflows and outflows to and from wetland areas. Atmospheric deposition samples were collected in carboys placed near established rain gauges. These sample sites were chosen as indicators of MP deposition into and out of the region’s wetland systems. MPs were extracted from each sample, enumerated, and categorized by particle morphology and polymer type. Average MP particle abundances in the sediment and surface water samples ranged from 344 to 538 particles kg⁻¹ (dry weight) and 2–68 particles m⁻³, respectively. Atmospheric MP deposition ranged from 5.8 to 22.6 particles m⁻² d⁻¹. Fibers were the most abundant MP particle type found in each sample type (sediment, surface water, and atmospheric deposition), followed by fragments. These results suggest that input and retention of MPs are pervasive in the Great Lakes region and surrounding wetland areas.

9 Jun 2025

Review of Remote-Sensing Methods for Mapping Riparian and Submerged Aquatic Vegetation: Support for Ecosystem Restoration Monitoring and Flood Risk Management

Abstract: Riparian vegetation, defined as multilayered herbaceous and woody plant communities along river margins or bank edges, and freshwater submerged aquatic vegetation (SAV), described as rooted aquatic plants in shallow rivers, lakes, and estuaries, are key factors influencing the connection between river and floodplain systems. These vegetation types are often used as indicators of riparian health. Current data on riparian vegetation and SAV are essential for addressing future water resource needs, particularly for restoration monitoring and flood risk management. The US Army Corps of Engineers (USACE), as the federal government’s largest water resources development and management agency, requires updated monitoring and assessment methods to support the development, utilization, and conservation of water and related resources. Assessing large riparian corridors involves characterizing baseline conditions, habitat extents, vegetation patterns, and health. Vegetation and habitat data are critical for evaluating the effects of project operations, resource management, and restoration outcomes downstream from USACE dams. However, obtaining such data across large, dynamic, and inaccessible river reaches is challenging. Integrating field-based techniques with remote-sensing technology offers opportunities to map larger areas comprehensively and adapt to future water resource needs. This report reviews re-mote sensing methods for mapping riparian and SAV habitats with emphasis on vegetation characteristics.

5 Jun 2025

Incorporating Natural and Nature-Based Features in an Urban California Creek Through Application of Engineering With Nature® Principles

Purpose: Since its launch in 2021, the Engineering With Nature® (EWN®) program has funded research focused in a variety of environments, particularly along marine and freshwater coasts and fluvial (riverine) systems. Until recently, there has been less focus on applying EWN principles in urban landscapes and watersheds to help manage flood risk, a main civil works mission of the US Army Corps of Engineers (USACE). Natural hazard challenges, including intense rainfall events, are contributing to flooding and prompting the need for more sustainable infrastructure to reduce flood risks in urban areas. This is especially relevant when such nature-based solutions (NBS) are desired by stakeholders who stand to benefit from the project. This technical note documents a USACE Chicago District (LRC) project that supports USACE Los Angeles District (SPL) to incorporate EWN principles in an urban ephemeral creek to reduce flood risk while providing other environmental, social, and economic benefits.

4 Jun 2025

Floridan Aquifer System (FAS) Aquifer Material Collection and Screening: Investigating Arsenic Fate and Transport Under Lab-Simulated Aquifer Storage and Recovery (ASR) Conditions in the FAS—Task A Report

Abstract: The US Army Engineer Research Development Center is leading a laboratory study to quantify arsenic release that could occur during large-scale aquifer storage and recovery (ASR) operations in the anoxic Floridan Aquifer System (FAS). FAS materials containing arsenic must be collected and preserved under anoxic conditions to complete the laboratory study. This report describes collection, preservation, and initial characterization results of FAS material collected. Analysis of water surrounding the FAS material during storage detected some arsenic, suggesting arsenic presence in the solids. In-depth characterization of a single sample confirmed storage conditions were anoxic; no arsenic was detected in surface scrapings collected from the sample solids. Initial characterization results suggested FAS materials collected were suitable for use in the planned laboratory study and that storage methods were suitable for preserving collected materials.

4 Jun 2025

Comprehensive Marsh Model Demonstration—Seven Mile Island Innovation Laboratory: Integrating Hydrodynamic, Morphodynamic, and Vegetation Modeling Components Using the Landlab Toolkit

Abstract: Marshes are highly dynamic landscapes that are shaped through feedbacks between hydrodynamic, morphodynamic, and ecological processes. Future marsh resilience is therefore dependent on the interaction between these different drivers rather than any individual piece. Marshes face a variety of threats, both natural and anthropogenic, resulting in a need for restoration actions that increase survivability. Because many of these threats are unprecedented or acting at unprecedented rates, statistical models do not adequately represent future conditions and require process-based models to better capture the complex interactions between both physical and ecological processes. This report demonstrates how to develop a comprehensive marsh model that integrates tidal flow, morphodynamics, and vegetation growth using the Python based Landlab toolkit. The model was applied to a site within the Seven Mile Island Innovation Laboratory complex in coastal New Jersey.

4 Jun 2025

Developing an Ecosystem Goods and Services Assessment Framework: Products and Resources

Purpose: The Environmental Research Area Review Group has long recognized a need to understand the role of Ecosystem Goods and Services (EGS) in US Army Corps of Engineers (USACE) civil works planning. An EGS Work Unit, funded by the Ecosystem Management and Restoration Research Program (EMRRP), has collaborated for more than a decade to develop many products and resources useful to USACE planners and policy makers. This technical note reviews the body of work produced by this large, diverse, and dedicated team.

20 May 2025

Guidance for Managers of USACE Waterbodies: Deploying the ERDC CyanoSTUN™ for Suppression of Cyanobacterial Harmful Algal Blooms

Purpose: The purpose of this document is to guide US Army Corps of Engineers (USACE) district personnel in using the US Army Engineer Research and Development Center’s (ERDC) CyanoSTUN™ (Cyanobacterial Suppression Through Ultraviolet-Light-C Neutralization) vessel for suppression of cyanobacterial harmful algal blooms (cyanoHABs). This document describes CyanoSTUN’s capabilities and components, intended operating conditions, and instructions for safe and effective operation of the vessel.

9 May 2025

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

Abstract: The paper describes our project to develop, verify, and deploy an All-Hazards Return of Investment model for the U.S. Army Engineer Research and Development Center 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 was required by U.S. code and DoD guidance, as well as an army strategic plan stipulating an ROI model to evaluate relevant resilient strategies. 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 model calculates the expected net present cost without the resilient strategy, with the resilient strategy, and ROI for each. The minimum viable product ROI model was formulated mathematically, coded in Python, verified using hazard scenarios, and provided to the ERDC for implementation.

6 May 2025

Technical Recommendations for the Identification and Management of Potential Acid Sulfate Soils in an Ecological Restoration Context

Abstract: Restoration projects are being implemented to address natural and anthropogenic threats to coastal wetlands, including increased inundation and historic land use alterations. The US Army Corps of Engineers (USACE) and other organizations introduce dredged sediments into coastal environments to increase elevation and stabilize marsh platforms. However, some dredged sediments either contain iron sulfide compounds (i.e., iron monosulfide [FeS] and pyrite [FeS₂]) or form them after application. Under aerobic conditions, FeS and FeS₂ can rapidly oxidize, which generates acidity that can dramatically lower the soil pH, impacts plant establishment, and threatens the success of wetland restoration projects. Recommendations are needed to properly manage iron sulfide containing materials through project design, screening, monitoring, and adaptive management. Tools and techniques exist to evaluate dredged sediments for the presence of FeS and FeS₂ prior to and following marsh sediment applications, and project design and construction approaches can minimize associated acidification risks. This report provides a framework for properly identifying and managing sediments containing iron sulfide minerals during wetland restoration projects. These technical recommendations provide dredged sediment beneficial use practitioners a decision support tool for the successful management of iron sulfide containing dredged sediments to increase the ecological function and sustainability of coastal wetlands.

1 May 2025

Resilience: Directions for an Uncertain Future Following the COVID-19 Pandemic

Abstract: The concept of resilience is multi-faceted. This commentary builds upon the analytical distinctions of resilience provided by Urquiza et al. (2021, https://doi.org/10.1029/2020EF001508). In response to this article, we emphasize several distinctions between resilience and other systems concepts. These include distinctions between resilience, risk, and vulnerability, the tradeoff between resilience and efficiency, resilience contrasted with robustness, the relationship between resilience and sustainability, and finally methods for building resilience-by-design or resilience-by-intervention. Improving understanding of these concepts will enable planners to select resilience strategies that best support their system goals. We use examples from the 2020–2021 coronavirus pandemic to illustrate the concepts and the juxtapositions between them.