21 May 2026

Evaluation of Shore Protection Alternatives at Crescent Beach, Indiana

Abstract: This report documents a numerical modeling investigation of shore protection alternatives at Crescent Beach, Indiana. The integrated flow, wave, sediment transport, and morphology change Coastal Modeling System (CMS) and the long-term shoreline evolution model, GenCade, were applied to evaluate alternatives. Sediment, elevation, and hydrodynamic data were collected nearby to improve model calibration and validation. Eight alternatives were evaluated, with coastal structures in four, beach nourishments in three, and one with both. Structures other than the continuous rubble ridge (Alternative 4) had minimal or negative influences on sediment transport. Stone sizes and costs were estimated for Alternative 4 using StormSim and extremal forcing from the Coastal Hazards System (CHS) Great Lakes Study, but CMS does not predict impacts that justify rubble ridge construction costs. CMS and GenCade were applied to beach nourishments across a range of volume and sediment grain size distributions. Model evaluations indicate that beach nourishment is the most effective shoreline protection technique, using coarse sand mixed with small stones to achieve a median grain size (d50) of 1.80 millimeters successfully extends the beach nourishment lifecycle, and increasing nourishment volume to 87,455 cubic meters to span in front of Mount Baldy substantially increases downdrift benefits.

18 May 2026

Workflow to Build Space-Time Cubes in ArcGIS Pro with High-Resolution Elevation Data

Abstract: This Coastal and Hydraulics Engineering Technical Note (CHETN) presents a workflow to build space-time cubes (STCs) using high-resolution digital elevation models (DEMs). The workflow leverages ArcGIS Pro’s mosaic dataset architecture and multidimensional tools to analyze temporal changes across elevation datasets. This workflow is intended to (1) guide users who may not be familiar with STCs through a step-by-step workflow, (2) share a set of best practices, and (3) highlight considerations when using remotely sensed elevation datasets. This CHETN is a part of a larger effort to develop the next generation of volume change tools for application in the coastal environment.

15 May 2026

Application of Rapid Response Reporting Tools to Improve Harmful Algal Bloom Management: US Army Corps of Engineers (USACE)–Omaha District

Abstract: Harmful algal blooms (HABs) pose significant threats to critical water resources, including potable water supply, fish and wildlife propagation, recreation, and overall water quality, managed by the US Army Corps of Engineers (USACE). To address these challenges, USACE needs innovative technologies that can enhance monitoring and management across the diverse portfolio of inland waterbodies they oversee. This technical report presents a case study from the Omaha District in which open-source software (R), satellite imagery, and traditional water quality parameters were integrated to produce near-real-time reports to improve HAB monitoring and management. The approach enabled timely identification of the areas most susceptible to HABs and provided actionable data to inform management strategies, such as hypolimnetic withdrawal, and other management actions. The findings demonstrate that combining remote sensing with open-source analytics can serve as a proof of concept for improving the efficiency of HAB monitoring programs. Ultimately, these tools facilitate more responsive decision-making by reducing resource demands and establishing a foundation for broader adoption of open-source tools in HAB management across USACE districts.

14 May 2026

Engineering With Nature® Proving Grounds Innovation Handbook

Abstract: The Engineering With Nature® Proving Grounds Innovation Handbook provides a comprehensive framework for integrating innovative natural and nature-based features and sediment management strategies to address climate-driven hazards and increase resilience in coastal and fluvial environments. Developed through collaboration between engineers, scientist, landscape architects, and U.S. Army Corps of Engineers districts and divisions, the EWN Handbook showcases a diverse collection of projects within the four coasts of the United States and offers the wide range of approaches available to achieve multiple benefits (economic, ecological, and social) through the application of traditional engineering with natural infrastructure solutions. The document aims to offer practitioners ideas on how to incorporate EWN concepts and strategies in all phases to build more resilient, multifunctional projects that protect communities and ecosystems against future natural hazards.

13 May 2026

Processing and Optimization of Global Land Ice Measurements from Space (GLIMS) Glacier Polygon Shapefiles for Army Geospatial Data Model Integration

Abstract: This technical note documents the methodology used to prepare glacier polygon datasets from the Global Land Ice Measurements from Space (GLIMS) database for integration into Army geospatial workflows. The Army Geospatial Data Model contains a feature class within the GGDM (Ground-Warfighter Geospatial Data Model) for permanent snow, defined operationally as snow persisting on the ground for more than two years. However, in cryospheric science, snow that persists across multiple accumulation seasons transitions into firn and ultimately becomes glacial ice. Thus, most “permanent snow” surfaces are more accurately classified as permanent ice, and GGDM does not currently contain a dedicated feature class representing this land-surface category. The GLIMS database provides authoritative, globally maintained glacier and perennial ice extents, making it ideally suited to fill this structural gap in the GGDM schema. The purpose of this work is to (1) transform raw GLIMS glacier polygons into a clean, nonoverlapping, attribute-free dataset; (2) standardize the geometry for compatibility with GGDM; and (3) establish a US Army Engineer Research and Development Center (ERDC)–compliant workflow for maintaining a credible representation of global permanent ice surfaces.

13 May 2026

Geospatial AI (GeoAI) Agent Stack: Router-Based Orchestration and Design Rationale

Abstract: This report summarizes the current state of a router-based, multiagent Geospatial AI (GeoAI) system designed to reliably execute geospatial workflows while retaining the flexibility of large language model (LLM) reasoning. The architecture is intentionally both language-model agnostic and orchestration-framework agnostic to support organizational controls and mandates, and it is designed to operate in air-gapped environments. It uses a domain router to scope tools before the model is invoked; a microrouter to decide whether the system should execute tools, retrieve knowledge, or produce a direct response; and a bounded cycle of execution and validation that supports multistep tool use. The design emphasizes determinism after the model makes decisions, strict boundaries around what the model can “see,” and modularity that keeps core business logic largely independent from orchestration and tool-protocol frameworks. The remainder of this report describes the architecture as implemented today, explains the design rationale, and outlines anticipated future work.

13 May 2026

Beach-fx Version 3.0 User’s Manual

Abstract: The need to strengthen the linkages between engineering analyses (project performance and evolution) and planning functions (alternative analysis and economic justification) with respect to coastal storm damage reduction projects within the US Army Corps of Engineers led to the development of the life-cycle simulation model Beach-fx. Beach-fx provides a comprehensive analytical framework for evaluating the physical performance and economic benefits and costs of shore protection projects, particularly beach nourishment along sandy shores. The model has been implemented as an event-based Monte Carlo life-cycle simulation tool that is run on desktop computers. This report describes the components, purpose, and operational function of the Beach-fx graphical user interface, including navigation within the interface and the organization and specification of all model input and output data.

12 May 2026

A Scalable Algorithm for Dynamic Vector Model Representation Utilizing Time-Series Reduction

Abstract: This document follows a technical report published by the US Army Engineer Research and Development Center–Geospatial Research Laboratory (ERDC-GRL), Time-Series Reduction for Dynamic Vector Model Attribute Representation in a Geographic Information System (ERDC/GRL TR-24-2, Drouillard and Lewis 2024). In that publication, we described the theoretical basis for extracting and modeling raster-format spatiotemporal phenomena for inclusion as a vector model attribute and provided a preliminary Python code example that was unsuitable for large-scale application. This report details the algorithm we subsequently developed to enable global-scale application of the time-series reduction method in service of the Intelligent Environmental Battlefield Awareness (IEBA) project.

12 May 2026

Barge Arrest System for Dams on Inland Waterways: Design Criteria

Abstract: The US Army Engineer Research and Development Center (ERDC), through the Navigation Systems Research Program, has begun developing a barge arrest system to reduce the damage and recovery costs of allisions (impact events) at US Army Corps of Engineers (USACE) lock and dam (L&D) sites. This development effort addresses a need for a mitigation strategy to address allisions from uncontrolled, breakaway barges following accidents that occur on a relatively frequent basis near USACE L&D sites summarized in the USACE Statement of Need 1974. These allisions have caused millions of dollars in recovery and repair costs to both the L&D structure and to navigation industry property (USACE 2005). In extreme situations, barge impacts to multiple gates have inhibited USACE’s ability to regulate water levels. This Coastal and Hydraulics Engineering Technical Note (CHETN) describes the general problem and findings from an initial design charette conducted with USACE subject matter experts (SMEs) across various technical disciplines. This initial design charette focused on the identification of design criteria for the prototype design and potential case study sites.

11 May 2026

Hydrologic Mechanisms for 2022 Yellowstone River Flood and Comparisons to Recent Historic Floods

Abstract: In June 2022, a historic flood event occurred in the headwaters of the Yellowstone River Basin. The flood resulted in millions of dollars in damages and substantial interruptions to Yellowstone National Park. The 2022 flood event was substantially higher in magnitude than other high- peak flow events over the last 30 years. The high discharge was primarily due to the combination of hydrologic mechanisms initiated by rain-on-snow, including a high- elevation snowpack that peaked later than average. However, the contributions of each hydrologic driver, rain and snow, have not been quantified and could be important for understanding future flood events in the region. The contribution of snowmelt to the total terrestrial water input (TWI) varied throughout the area, yet was concentrated in the headwaters of the Yellowstone, Stillwater, and Boulder rivers, along with the headwaters of Rock Creek in Wyoming and Montana. The primary atmospheric contributions to the TWI during the 2022 event were precipitation from moisture transported from the Pacific Ocean that converged over the Greater Yellowstone Area (GYA) and snowmelt from residual snowpack in the northeast part of Yellowstone National Park.