5 Sep 2023

Proceedings from the US Army Corps of Engineers (USACE) 2021 Beneficial Use of Dredged Material Virtual Workshop

Abstract: On 13–15 July 2021, 58 representatives from Headquarters, US Army Corps of Engineers (USACE), 2 USACE Divisions, 14 USACE districts, and US Army Engineer Research and Development Center’s (ERDC) Environmental (EL) and Coastal Hydraulics (CHL) Laboratories came together and participated in a virtual workshop on the beneficial use (BU) of dredged material. The overall goal was to organize the BU community across USACE and develop a path forward to increase BU practices. Talks and discussions focused on the current status of BU across USACE, including success stories on innovative BU projects, challenges related to regulatory issues, state and federal policies, technical logistics, and stakeholder engagement, as well opportunities for expanding current practices to include more regular and innovative applications. The workshop was cohosted by Dr. Amanda Tritinger (CHL) and Dr. Kelsey Fall (CHL) on behalf of the Engineering With Nature®, Coastal Inlets Research Program, Dredging Operations and Environmental Research, and Regional Sediment Management research programs. The workshop concluded by introducing and awarding the first annual Timothy L. Welp Award for Advancing Beneficial Use of Dredged Sediments to recognize teams (with members across and outside of USACE) that have advanced progress on BU through collaboration, partnering, and innovation.

24 Aug 2023

Houston Ship Channel Numerical Model Update and Validation

Abstract: The Houston Ship Channel (HSC) is one of the busiest deep-draft navigation channels in the United States and must be able to accommodate increasing vessel sizes. The US Army Corps of Engineers, Galveston District (SWG), requested the US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, update and revalidate a previously developed three-dimensional Adaptive Hydraulics (AdH) hydrodynamic and sediment model of the HSC, Galveston, and Trinity Bays. The model is necessary for analyzing potential impacts on salinity, sediment, and hydrodynamics due to alternatives designed to reduce shoaling in the HSC. SWG requested an updated validation of the previously developed AdH model of this area to calendar years 2010 and 2017, utilizing newly collected sediment data. Updated model inputs were supplied for riverine suspended sediment loads as well as for the ocean tidal boundary condition. The updated model shows good agreement to field data in most conditions but also indicates potential issues with freshwater flow inputs as well as the ocean salinity boundary condition.

24 Aug 2023

3D Measurements of Water Surface Elevation Using a Flash Lidar Camera

Abstract: This Coastal and Hydraulics Engineering technical note (CHETN) presents preliminary results from a series of tests conducted at the US Army Engineer Research and Development Center (ERDC), Coastal and Hydraulics Laboratory (CHL), Field Research Facility (FRF), in Duck, North Carolina, to explore the capabilities and limitations of the GSFL16K Flash Lidar Camera in nearshore science and engineering applications. The document summarizes the spatial coverage and density of data collected in three deployment scenarios and with a range of tuning parameters and provides guidance for future deployments and data-collection efforts.

24 Aug 2023

Measuring Maritime Connectivity to Puerto Rico and the Virgin Islands Using Automatic Identification System (AIS) Data

Abstract: The purpose of this Coastal and Hydraulics Engineering technical note (CHETN) is to summarize a portion of recently published work (Young, Kress, et al. 2022) that used archival Automatic Identification System (AIS) data to measure the commercial vessel traffic connected to Puerto Rican and US Virgin Island (USVI) port areas from January 2015 to June 2020. Vessel movement derived from AIS was aggregated to construct a network that measured the port-to-port connectivity for all ports in the network and the interconnectivity of traffic between those ports. AIS data provided a description of vessel movement and the identification of specific vessel classes. Metrics such as interconnectedness can be used in conjunction with standard US Army Corps of Engineers (USACE) metrics describing waterway utilization, which traditionally have included total tonnage and specific commodity tonnage. The ability to consider the self-selected vessel-type broadcast via AIS, as well as dominant commodity type and tonnage reported through statistical publications, provides a fuller and more accurate description of waterway capacity utilization. This knowledge, along with port-to-port interconnectedness, reveals potential redundancies between ports, robustness across supply chains, and the impacts of seasonality, thereby allowing the USACE to expand its understanding of maritime supply-chain resilience.

24 Aug 2023

Geomorphic Metrics Used in FluvialGeomorph

Abstract: FluvialGeomorph (FG) is a geographic information system-based geomorphic analysis toolkit that analyzes high-resolution terrain data to provide river-reach assessments for watershed studies. This report demonstrates the utility of FG to identify physical stream channel characteristics that are used to determine channel stability. The FG toolbox is a remote-sensing approach based on lidar data, designed to measure channel, floodplain, valley, and watershed metrics necessary for watershed assessments. Currently, channel slope and cross-sectional analysis and planform metrics are being evaluated with existing lidar data from different hydrophysiographic regions within the United States. Recent study areas include the Northwest, Southwest, South, Midwest, and upper Midwest of the United States.

10 Aug 2023

Sensitivity of Simulated Flaw-Height Estimates to Phased Array Scan Parameters

Abstract: Phased array ultrasonic testing (PAUT) is a nondestructive testing (NDT) technique for detecting and sizing flaws in welds. Estimates of flaw size are sensitive to a variety of PAUT scan parameters. In this study, estimates of flaw height are simulated using computer software. The sensitivity of these estimates to selected PAUT scan parameters is analyzed to identify those that have the greatest influence on estimates of flaw height. Understanding how varying different parameters within a phased array instrument affects the accuracy of flaw-height estimates helps to validate PAUT scan procedures and improve flaw-height estimates. For this research, a series of permutations on selected flaws were performed to see how certain parameters affect the accuracy in sizing flaw height. In addition, an analysis on how beam spread leads to flaw sizing inaccuracies was also conducted as part of this work.

8 Aug 2023

Evaluation of Structural and Operational Alternatives to Optimize the Distribution of Water and Sediment in the Passes of the Mississippi River

Abstract: Mississippi River shoaling and dredging processes in the vicinity of Head of Passes and in Southwest Pass were investigated. Existing rates of deposition and dredging were determined using near-daily eHydro bathymetric surveys, National Dredging Quality Management dredge operating data, and geospatial processing steps developed for this study. These surveys provide a means to characterize the highly dynamic and variable sedimentation patterns observed in the navigation channel. The HEC-6T one-dimensional numerical sedimentation model was used to evaluate possible modifications to the distribution of water and sediment in the Mississippi River near Head of Passes in an attempt to reduce shoaling in the navigation channel. The model was used to evaluate the effects of partial closures of several distributaries downstream from Venice and to evaluate the effects of channel widening and channel deepening adjacent to the Hopper Dredge Disposal Area at Head of Passes. In this study, various structural alternatives were compared to a base test that represented existing conditions. Sedimentation and dredging effects were projected 50 years into the future.

7 Aug 2023

Acoustic Doppler Current Profiler Study of Water and Sediment Movement through a Deep Scour Hole in the Lower Mississippi River

Abstract: A series of acoustic Doppler current profiler (ADCP) transects were collected through a deep scour hole at the bend near River Mile 60 on the Lower Mississippi River. The measurements were collected during both a low and a high flow. The ADCP results show a 3D flow field through the deep bend. The backscatter intensity of the ADCP measurements indicates the majority of the sediment remains close to the inside of the bed and high in the water column, with minimal concentrations at the bottom of the bend. These findings have implications for numerical sediment transport models, which tend to deposit material at the bottom of deep scour holes like the one in this study

7 Aug 2023

Soil-Moisture Estimation of Root Zone through Vegetation-Index-Based Evapotranspiration-Fraction and Soil-Properties (SERVES) User’s Manual Version 1.0

Purpose: The purpose of this user’s guide is to provide background methods and implementation guidance on the Soil-moisture Estimation of Root Zone through Vegetation-Index-Based Evapotranspiration-Fraction and Soil-Properties (SERVES) model (Pradhan 2019).

2 Aug 2023

Sustainable bank and channel stabilization techniques in arid southwest streams

Abstract: Channel stabilization and enhancement approaches take many different forms and are implemented using varying construction methods, materials, and techniques. The purpose of this study is to provide a comprehensive evaluation of sustainable streambank stabilization measures that are typically applied in arid southwest (SW) streams. This study was conducted at the request of the US Army Corps of Engineers (USACE), Albuquerque District (SPA), and USACE Headquarters. The document also provides rationale for evaluating bank and bed stabilization measures.