15 Sep 2023

Real-Time Forecasting Model Development Work Plan

Abstract: The objective of the Lowermost Mississippi River Management Program is to move the nation toward more holistic management of the lower reaches of the Mississippi River through the development and use of a science-based decision-making framework. There has been substantial investment in the last decade to develop multidimensional numerical models to evaluate the Lowermost Mississippi River (LMMR) hydrodynamics, sediment transport, and salinity dynamics. The focus of this work plan is to leverage the existing scientific knowledge and models to improve holistic management of the LMMR. Specifically, this work plan proposes the development of a real-time forecasting (RTF) system for water, sediment, and selected nutrients in the LMMR. The RTF system will help inform and guide the decision-making process for operating flood-control and sediment-diversion structures. This work plan describes the primary components of the RTF system and their interactions. The work plan includes descriptions of the existing tools and numerical models that could be leveraged to develop this system together with a brief inventory of existing real-time data that could be used to validate the RTF system. A description of the tasks that would be required to develop and set up the RTF system is included together with an associated timeline.

18 Aug 2021

Houston Ship Channel Expansion Channel Improvement Project (ECIP) Numerical Modeling Report: BABUS Cell and Bird Island Analysis

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 Engineer District, Galveston (SWG), requested the Engineer Research and Development Center, Coastal and Hydraulics Laboratory, perform hydrodynamic and sediment modeling of proposed modifications in Galveston and Trinity Bays and along the HSC. The modeling results are necessary to provide data for hydrodynamic, salinity, and sediment transport analysis. SWG provided three project alternatives that include closing Rollover Pass, Bay Aquatic Beneficial Use System cells, Bird Islands, and HSC modifications. These alternatives and a Base (existing condition) will be simulated for present (2029) and future (2079) conditions. The results of these alternatives/conditions as compared to the Base are presented in this report. The model shows that the mean salinity varies by 2–3 ppt due to the HSC channel modifications and by approximately 5 ppt in the area of East Bay due to the closure of Rollover Pass. The tidal prism increases by 2.5% to 5% in the alternatives. The tidal amplitudes change by less than 0.01 m. The residual velocity vectors vary in and around areas where project modifications are made.

25 Aug 2020

PUBLICATION NOTICE: New York/New Jersey Harbor Sedimentation Study: Numerical Modeling of Hydrodynamics and Sediment Transport

Abstract: The New York/New Jersey Harbor (NYNJH) is a vital economic resource for both the local economy and the entire US economy due to the vast quantity of imports and exports handled by the numerous ports in this waterway. As with most ports, there is a significant, recurring expense associated with dredging the navigation channels to the authorized depths. In an effort to determine the impact of channel enlargements (“the project”) on dredging volumes, a numerical model study was performed. The advantage of a numerical model study is the ability to isolate individual system modifications and associated impacts in terms of dredging volumes. Five years (1985, 1995, 1996, 2011, and 2012) were simulated for both the with- and without-project conditions to determine the impact of the channel deepening on the dredging requirements for a wide range of meteorological conditions including storm events. The numerical model results were analyzed to provide insight into which locations will experience increased/decreased deposition and quantify the amount of increase/decrease for a given channel reach. The model results indicate a relatively minor increase in the total dredge volumes for the NYNJH with the increase being insignificant in comparison to the natural variability in dredge volumes across years.

28 Apr 2020

PUBLICATION NOTICE: Baldcypress (Taxodium distichum) at the Wallisville Lake Project: A Review of Applicable Literature and Management Considerations

Abstract: Changing hydropatterns within the Wallisville Lake Project, near the mouth of the Trinity River in Chambers and Liberty Counties, Texas, have the potential to alter baldcypress forest resiliency. Increasing water levels support saltwater barrier operations while maintaining navigation and recreational access. However, potential impacts of increased water levels on the baldcypress forests are of particular concern because these ecosystems provide unique ecological value and wildlife habitat. The maintenance, succession, and resiliency of baldcypress under various flooding, salinity, and inundation regimes remain poorly defined and pose challenges to resource managers. This report reviews available literature pertaining to salinity and inundation impacts to baldcypress forests. Specific emphasis is placed on the ecological effects of water quality and quantity on the health and persistence of baldcypress. The information gathered in this report is intended to supplement material in the Wallisville Lake Project Water Control Manual to improve management of baldcypress forest conditions and avoid negative ecological impacts. Additionally, this report provides management considerations designed to maintain or enhance baldcypress forests within the Wallisville Lake Project.