Ben R. Hodges

• Ph.D.
• University of Texas at Austin

Urban expansion and the increasing frequency and intensity of extreme precipitation events bring new challenges to stormwater collection systems. One underrecognized issue is the occurence of transient flow conditions that lead to adverse multiphase flow interactions (AMFI): essentially, the formation, collapse, and uncontrolled release of air pock...

The EPA's Storm Water Management Model (SWMM) has been applied across the globe for citywide stormwater modeling due to its robustness and versatility. Recent research indicated that SWMM, with proper setup, can be applied in the description of more dynamic flow conditions, such as rapid inflow conditions. However, stormwater systems often have geo...

The SWMM5+ project began with the observation that the EPA SWMM hydraulic solver: (i) is the primary consumer of computational time, (ii) is the source of model instability/mass non-conservation, (iii) limits parallelization, and (iv) cannot support mass-conservative Advection-Diffusion-Reaction (ADR) transport modeling. The new SWMM5+ solver provi...

Intense rain events and sprawling urbanization have contributed to more frequent flash flooding in cities, often due to the pressurization of drainage systems. Stormwater collection networks (SCNs) can become pressurized if their conveyance capacity is exceeded, leading to on-street flooding through backflow out of curb inlets. Due to the complexit...

A new formulation of the Preissmann Slot for modeling surcharged (pressurized) one-dimensional (1D) pipe flow is presented. The Dynamic Preissmann Slot (DPS) is derived in a nondimensional form where the slot is treated as transient storage, which is a function of slot cross-sectional area rather than width. The use of transient storage area remove...

This manual provides the fundamentals for using the SWMM5+ hydraulics engine coupled to the the US Environmental Protection Agency's Storm Water Management Model (EPA SWMM). SWMM5+ provides a finite-volume solution for the dynamic wave equation (Saint-Venant equations) that replaces the link-node finite-difference approach in EPA SWMM. The principa...

This manual documents the methods and code for the SWMM5+ hydraulics engine. This code is a companion to the US Environmental Protection Agency's Storm Water Management Model (EPA SWMM). The SWMM5+ hydraulics engine introduces a finite-volume solution for the dynamic wave equation (Saint-Venant equations) that replaces the link-node finite-differen...

This guide provides installation instructions for v1.0 of the SWMM5+ hydraulics engine. This engine is a companion code to the US Environmental Protection Agency's Storm Water Management Model (EPA SWMM). The SWMM5+ code is linked with EPA SWMM code during compilation to simulate a coupled hydrology/hydraulic system.

Modeling transient flow in water transport networks is characterized by hyperbolic partial differential equations. Existing commercial and open-source software for transient modeling in water transport networks (WTNs) have limitations, such as lack of scalability and compatibility with high-performance computers, difficulty to systematically execut...

System partitioning for effective simulation of civil infrastructure flow networks on parallel processors is a non-trivial problem. Arbitrary partitioning focused only on balancing processor workload can lead to a large inter-processor communication burden that limits parallel speedup. Thus, there is a need for intelligent partitioning algorithms t...

div>System partitioning for effective simulation of civil infrastructure flow networks on parallel processors is a nontrivial problem. Arbitrary partitioning focused only on balancing processor workload can lead to a large interprocessor communication burden that limits parallel speedup. Thus, there is a need for intelligent partitioning algorithms...

div>System partitioning for effective simulation of civil infrastructure flow networks on parallel processors is a nontrivial problem. Arbitrary partitioning focused only on balancing processor workload can lead to a large interprocessor communication burden that limits parallel speedup. Thus, there is a need for intelligent partitioning algorithms...

A new sweep-search algorithm (SSA) is developed and tested to identify the channel geometry transitions responsible for numerical convergence failure in a Saint-Venant equation (SVE) simulation of a large-scale open-channel network. Numerical instabilities are known to occur at “sharp” transitions in discrete geometry, but the identification of pro...

The response of the Maroon reservoir in southwest Iran is modeled to evaluate possible impacts of 21st century climate change. Projections of 3 CMIP5 General Circulation Models (GCMs) were investigated using 2 Representative Concentration Pathways (RCP4.5 and RCP8.5), which respectively represent low/medium and high greenhouse gas emission scenario...

Total dissolved gas supersaturation (TDGS) produced by flood flows over a high dam has negative consequences on downstream fish. Reducing the total dissolved gas (TDG) levels and/or providing adequate low‐TDGS fish shelter areas remains a challenge. The presence of a low‐TDG‐saturation (LTS) zone at river confluences can protect the fish from harmf...

Modeling transient flow in networked dynamical systems characterized by hyperbolic partial differential equations (PDEs) is essential to engineering applications. Solutions of hyperbolic PDEs are commonly found using the method of characteristics (MOC), particularly when modeling the water hammer phenomenon in water distribution systems (WDSs), whi...

A new high-performance numerical model (Frehg) is developed to simulate water flow in shallow coastal wetlands. Frehg solves the 2D depth-integrated, hydrostatic, Navier–Stokes equations (i.e., shallow-water equations) in the surface domain and the 3D variably-saturated Richards equation in the subsurface domain. The two domains are asynchronously...

The solution stability of river models using the one-dimensional (1D) Saint-Venant equations can be easily undermined when source terms in the discrete equations do not satisfy the Lipschitz smoothness condition for partial differential equations. Although instability issues have been previously noted, they are typically treated as model implementa...

Piping systems (e.g., storm sewers) that transition between free-surface flow and surcharged flow are challenging to model in one-dimensional (1D) networks as the continuity equation changes from hyperbolic to elliptic as the water surface reaches the pipe ceiling. Previous network models are known to have poor mass conservation or unpredictable co...

One of the challenges for hydropower dam operation is the occurrence of supersaturated total dissolved gas (TDG) levels that can cause gas bubble disease in downstream fish. Supersaturated TDG is generated when water discharged from a dam entrains air and temporarily encounters higher pressures (e.g. in a plunge pool) where TDG saturation occurs at...

In this study, effects of basin morphology are shown to affect density current hydrodynamics of a large reservoir using a three-dimensional (3D) hydrodynamic model that is validated (but not calibrated) with in situ observational data. The AEM3D hydrodynamic model was applied for 5-month simulations during winter and spring flooding for the Maroon...

Tidal freshwater zones (TFZs) are transitional environments between terrestrial and coastal waters. TFZs have freshwater chemistry and tidal physics, and yet are neither river nor estuary based on classic definitions. Such zones have been occasionally discussed in the literature but lack a consistent nomenclature and framework for study. This work...

Abstract. The solution stability of river models using the one-dimensional (1D) Saint–Venant equations can be easily undermined when source terms in the discrete equations do not satisfy the Lipschitz smoothness condition for partial differential equations. Although instability issues have been previously noted, they are typically treated as model...

This work introduces WUDESIM, an open-source C/C++ toolkit for modeling water quality in the dead-end branches of drinking water distribution networks. WUDESIM is linked to the programmers’ toolkit of EPANET, a widely-used public-domain water network analysis model. In place of the advection-based water quality module in EPANET, WUDESIM allows the...

This work presents a vision of future water resources hydrodynamics codes that can fully utilize the strengths of modern high-performance computing. The advances to computing power, formerly driven by the improvement of central processing unit processors, now focus on parallel computing and, in particular, the use of graphics processing units (GPUs...

Oil spills caused by ship collisions and offshore oil wells are an ongoing risk for estuaries in the northern Gulf of Mexico. The fate and transport of the oil spill across the interface between a bar-built estuary and the adjacent coast are influenced by multi-scale forcing mechanisms and their corresponding interactions. Of primary interest are t...

Empirically quantifying tidally-influenced river discharge is typically laborious, expensive, and subject to more uncertainty than estimation of upstream river discharge. The tidal stage-discharge relationship is not monotonic nor necessarily single-valued, so conventional stage-based river rating curves fail in the tidal zone. Herein, we propose a...

A new finite-volume numerical method for the one-dimensional (1D) Saint-Venant equations for unsteady open-channel flow is developed and tested. The model uses a recently-developed conservative finite-volume formulation that is inherently well-balanced for natural channels. A new timescale interpolation approach provides transition between 1st-orde...

Porosity-based subgrid topography models often fail to capture the effects of subgrid-scale topographic features in the interior of coarse grid cells. Existing approaches that modify bottom roughness or a drag coefficient are inadequate for macro-structures (large emergent or submerged obstacles) in subgrid-scale narrow twisted channels. Such struc...

Reduced freshwater inflow into a coastal marsh can result in environmental stress through episodic hypersalinity. Hydrodynamic models can be used to evaluate salinity-control strategies when freshwater supplies are constrained by climate or increasing urban demands. However, there remain significant scientific, engineering, and technical barriers t...

In this paper, we present the results of numerical simulations matched to laboratory experiments of tidal, starting-jet vortices forming at idealized, barotropic inlets. The laboratory experiments are for sinusoidally varying inflow/outflow along a wide, flat basin. Inlet configurations include simple inlets with negligible channel length as well a...

The next generation of the public domain Storm Water Management Model (SWMM) code needs to be able to effectively use parallelization of 1000+ threads for high-resolution simulation of large urban drainage systems. We propose a new explicit solution technique using a “no-neighbour” finite-volume algorithm. A no-neighbour algorithm is strictly limit...

Reliable and rapid real-time prediction of likely oil transport paths is critical for decision-making from emergency response managers and timely clean-up after a spill. As high-resolution hydrodynamic models are slow, operational oil spill systems generally rely on relatively coarse-grid models to provide quick estimates of the near-future surface...

A new finite-volume numerical method for the one-dimensional (1D) Saint-Venant equations for unsteady open-channel flow is developed and tested. The model uses a recently-developed conservative finite-volume formulation that is inherently well-balanced for natural channels. A new timescale interpolation approach provides transition between 1st-orde...

This poster presents preliminary efforts from the NCIMM group at UT Austin to improve the computing speed of an explicit-solving version of the SWMM engine through the use of intelligent partitioning. The outline for a novel heuristic partitioning scheme is included.

A 2D depth-integrated subgrid hydrodynamic model (FrehdC)is designed to simulate effects of subgrid-scale topography on flow and scalar transport in shallow coastal marshes using computationally-efficient grid cells that are coarser than many of the channelized paths through the marsh. The subgrid-scale topography is parametrized into four depth-de...

New integral, finite-volume forms of the Saint-Venant equations for one-dimensional (1-D) open-channel flow are derived. The new equations are in the flux-gradient conservation form and transfer portions of both the hydrostatic pressure force and the gravitational force from the source term to the conservative flux term. This approach prevents irre...

In operational oil spill modeling, hydrodynamic models often employ a coarse-resolution grid for computational efficiency. However, this practical grid resolution poorly resolves small-scale flow features, such as starting jet vortices (tidal eddies) that are common at the inlet of bar-built estuaries with narrow inlet channels, particularly where...

Total dissolved gas supersaturation (TDGS) downstream caused by spill discharge from high dams can easily cause fish to suffer from gas bubble disease (GBD). One potential approach to mitigate the impact of TDGS is at the confluence of a downstream tributary, where the introduction of low-TDG water might provide refuge space for fish. In this study...

This work describes the development of a plugin in the new SWMM-EPANET User Interface (UI) environment. The plugin package solves the well-studied least-cost design problem of water distribution systems, implementing genetic algorithms as the optimization approach. Simulation of water distribution systems is crucial for the technical planning and m...

New finite-volume forms of the Saint-Venant equations for one-dimensional (1D) open-channel flow are derived. The new equations are in the flux-gradient conservation form and serve to transfer portions of both the hydrostatic pressure force and the gravitational force from the source term to the conservative flux term. The derivation introduces an...

Flow directions are important because they may be used to derive flow paths. These parameters are requisite in terrain-based flood mapping methods. Prior algorithms of flow direction generation are based in digital elevation models alone. Implicit in these methods is the assumption that elevation is the sole determinant in flow directions; however,...

This work introduces the Locally Filtered Transport (LFT) method for numerical transport models. Locally turning off the transport computation in areas of nearly uniform concentration is proposed as a new approach for reducing computational cost in ecosystem models that require transport of tens to hundreds of constituent concentrations. The propos...

The exposure time is a water transport time scale defined as the cumulative amount of time a water parcel spends in the domain of interest regardless of the number of excursions from the domain. Transport time scales are often used to characterize the nutrient removal potential of aquatic systems, but exposure time distribution estimates are scarce...

Avalanches and subaqueous debris flows are two cases of a wide range of natural hazards that have been previously modeled with non-Newtonian fluid mechanics approximating the interplay of forces associated with gravity flows of granular and solid–liquid mixtures. The complex behaviors of such flows at unsteady flow initiation (i.e., destruction of...

Initial conditions for flows and depths (cross-sectional areas) throughout a river network are required for any time-marching (unsteady) solution of the one-dimensional (1-D) hydrodynamic Saint-Venant equations. For a river network modeled with several Strahler orders of tributaries, comprehensive and consistent synoptic data are typically lacking...

Debris flows such as avalanches and landslides are heterogeneous mixtures of solids and liquids but are often simulated as homogeneous non-Newtonian fluids using a Herschel-Bulkley model. By representing the heterogeneous debris as a homogeneous non-Newtonian fluid, it is possible to use standard numerical approaches for the Navier-Stokes equations...

Defining surface water systems as lentic or lotic is an important first step in linking hydrology and ecology. Existing approaches for classifying surface water as lentic (reservoir-like) or lotic (river-like) use qualitative observations, solitary snapshot measurements in time and space, or ecologic metrics that are not broadly repeatable. This st...

Initial conditions for flows and depths (cross-sectional areas) throughout a river network are required for any time-marching (unsteady) solution of the one-dimensional (1D) hydrodynamic Saint-Venant equations. For a river network modeled with several Strahler orders of tributaries, comprehensive and consistent synoptic data are typically lacking a...

As oil transport increasing in the Texas bays, greater risks of ship collisions will become a challenge, yielding oil spill accidents as a consequence. To minimize the ecological damage and optimize rapid response, emergency managers need to be informed with how fast and where oil will spread as soon as possible after a spill. The state-of-the-art...

Recent work with full-scale experiments indicates that there are fundamental problems with standard curb inlet design equations when applied to depressed curb inlets of 10 ft (3 m) or longer. A full-scale laboratory experiment showed that the latter part of a long inlet does not have a simple linear water surface profile at 100% interception, which...

Total dissolved gas (TDG) supersaturation downstream has a negative environmental effect on fishes. It is caused by discharge from high dams and increases the incidence of gas bubble disease and fish mortality. Downstream of a high dam, there is an area with low TDG saturation due to the gradual mass exchange of gases between the separation zone an...

NOTE: There are two versions of this. The most recent (2016) is what I will send you if you request a copy. Let me know if you actually want the older version (2000).

Eutrophication in lakes and reservoirs plays a key role in aquatic environments and water quality management by affecting oxygen and nutrient cycles, especially in deep and large impoundments. Prior to reservoir construction, understanding the potential for eutrophication would provide valuable information to water resources planners on the critica...

Estimation of the mass transfer rate at the air and water interface is critical for the accurate prediction of mass transfer in many fields. Supersaturation of the total dissolved gas (TDG) may occur during spillway discharging, causing a sudden increase in water temperature and extra photosynthesis of aquatic plants. The dissipation process of sup...

Schizothorax prenanti (S. prenanti) is a second-class provincial protected endemic fish within the upper reaches of the Min River. The spawning season of S. prenanti extends from March to April. Habitat alteration and the construction of multistage dams have resulted in a rapid decline of the S. prenanti population. To assess the potential effects...

Total dissolved gas (TDG) supersaturation can cause potentially fatal Gas Bubble Disease (GBD) in fish and is recognized for its severe environmental impact for high-dam operation conditions. The generation of supersaturated TDG in high-head hydropower project is substantially different from middle- or low-head projects that have been previously st...

Total dissolved gas (TDG) supersaturation on the upper Yangtze River basin is becoming increasingly serious because of the intense construction of high dams, posing a threat to resident fish. The tolerance and behavior characteristics of Rock Carp Procypris rabaudi preexposed to TDG-supersaturated water were evaluated by placing juveniles (weight 6...

A vessel-mounted acoustic Doppler current profiler study focusing on channel-scale flow patterns in Galveston Bay near the Houston Shipping Channel and the artificial (dredge spoil) Mid-Bay Island is described. Winds of 5-7 m/s at 215-230° from N were present during data collection, which was conducted both in the deep channel (15 m) and along the...

Turbidity currents move through the thalweg and seriously impact the whole lake ecosystem in the reservoirs with narrow-deep morphology. Controlling and minimizing the effects of increasing turbidity on the light penetration and aquatic ecosystem is of great importance in reservoir management. In this study a 3D hydrodynamic model coupled with a pa...

The Hydrodynamic and oil spill modeling system for Python (HyosPy) is presented as an example of a multi-model wrapper that ties together existing models, web access to forecast data and visualization techniques as part of an adaptable operational forecast system. The system is designed to automatically run a continual sequence of hindcast/forecast...

Moraine dam collapse is one of the causes of glacial lake outburst floods. Available models seek to predict both moraine breach formation and lake outflow. The models depend on hydraulic, erosion, and geotechnical parameters that are mostly unknown or uncertain. This paper estimates the outflow hydrograph caused by a potential erosive collapse of t...

New automated methods are developed for identifying narrow landscape features that cause hydrodynamic blocking and might have critical impacts for management models of river flooding, coastal inundation, climate change, or extreme event analysis. Lidar data processed into a fine-resolution raster (1 m × 1 m) can resolve narrow blocking features in...

Quantifying uncertainties in real-time operational oil spill forecasts remains an outstanding problem, but one that should be solvable with present science and technology. Uncertainties arise from the salient characteristics of oil spill models, hydrodynamic models, and wind forecast systems, which are affected by choices of modelling parameters. P...

New automated methods are developed for identifying narrow landscape features that cause hydrodynamic blocking and might have critical impacts for management models of river flooding, coastal inundation, climate change, or extreme event analysis. Lidar data processed into a fine-resolution raster (1 m × 1m) can resolve narrow blocking features in t...

Hydrodynamic models are tools for quantifying flow and transport through inland waters. Although such models can be visually quite stunning, their accuracy and believability depends on careful model selection, setup, validation, and analysis. This article examines general model types, capabilities and limitations. The focus is on underlying issues...

Moraine dam collapse is one of the causes of Glacier Lake Outburst Floods. Available models seek to predict both moraine breach formation and lake outflow. The models depend on hydraulic, erosion, and geotechnical parameters that are mostly unknown or uncertain. This paper estimates the outflow hydrograph caused by a potential collapse of the morai...

An automated method for visualizing oil spill forecasts using Google Maps and Google Earth has been integrated into a Hydrodynamic and Oil Spill Python (HyosPy) modeling system. HyosPy downloads wind and tide observations and forecasts, runs a hydrodynamic model (the Semi-Implicit Eulerian Lagrangian Finite Element), links to an oil spill model (Ge...

A new method is presented to provide automatic sequencing of multiple hydrodynamic models and automated analysis of model forecast uncertainty on a Linux based multi-processor workstation. A Hydrodynamic and oil spill model Python (HyosPy) wrapper was developed to run a sequence of hydrodynamic models, link with an oil spill model, and visualize re...

A new scalar transport method is proposed to reduce computational time when a large number of scalars are transported in coupled hydrodynamic-ecosystem models. The new Local Mass Transport (LMT) method confines subtime transport computations to regions where the local Courant-Freidrichs-Lewy (CFL) number exceeds a given numerical stability criteria...

This paper describes the Simulation Program for River Networks (SPRINT) that is proposed as a tool for studying Continental River Dynamics (CRD), the solution of physics-based equations for large-scale river networks. Existing coupled hydrologic/hydraulic models have been unable to solve the full Saint-Venant equations for river networks larger tha...

Electric circuits and river networks share similarities in both their network structure and derivation from conservation principals. However, the disciplines have evolved separately and developed methods and models. This paper presents the foundations for network analysis for both disciplines and shows how numerical methods developed for circuit si...

Electric circuits and river networks share similarities in both their network structure and derivation from conservation principals. However, the disciplines have evolved separately and developed widely different methods and models. Rivers and Electric Networks: Crossing Disciplines in Modeling and Simulation presents the foundations for network an...

Continental River Dynamics (CRD) is herein defined as modelling the flow dynamics in all channels of a continental-scale river basin using the physics-based Saint-Venant equations. At the boundary of hydraulics and hydrology, CRD requires significant collaborative efforts to make new progress. Six constraints and seven challenges are identified in...

A new method is presented to provide automatic sequencing of multiple hydrodynamic models and automated analysis of model forecast uncertainty. A Hydrodynamic and oil spill model Python (HyosPy) wrapper was developed to run the hydrodynamic model, link with the oil spill, and visualize results. The HyosPy wrapper completes the following steps autom...

Mixing processes in lakes are key factors controlling light availability for phytoplankton growth, but understanding the contribution of mixing is often confounded by other factors such as nutrient availability and species dynamics. Our study examined this problem in a low pH, geothermally heated lake dominated by one phytoplankton genus and lackin...

Elevated levels of total dissolved gas (TDG) may occur downstream of dams, leading to increased incidence of gas bubble disease in fish. Accelerating the dissipation of supersaturated TDG in the downstream river can mitigate this problem; however, data useful for modeling the dissipation of supersaturated TDG through the free surface in natural riv...

A short field reconnaissance of the bayous at the head of Mission Lake and Guadalupe Bay was conducted by Ben R. Hodges, Center for Research in Water Resources, The University of Texas at Austin, with the assistance of Mr. Jack Campbell on January 10, 2013. The photograph provides an overview of the waypoints and their relationships to the main fea...

Fully dynamic modeling of large scale river networks is still a challenge. In this paper we describe SPRINT, an interdisciplinary collaborative effort between computer engineering and hydroscience to address the computational aspect of this challenge. Although algorithmic details differ, SPRINT draws many design considerations from SPICE, one of th...

The central Texas corridor is one of the most flash flood-prone regions in the United States. Over the years, flash floods have resulted in hundreds of flood fatalities and billions of dollars in property damage. In order to mitigate risk to residents and infrastructure during flood events, both citizens and emergency responders need to exhibit pro...

This report presents a new method for coupling different hydrodynamic models with an oil spill transport model. The hydrodynamic models used are the two-dimensional (2D) TxBLEND model and the three-dimensional (3D) SELFE model. The oil spill transport model is the General NOAA Operational Modeling Environment (GNOME) developed and maintained by the...

A user's guide to the Nueces Delta hydrodynamic model v1.0 (NDHM) is discussed. The NDHM is a customized implementation of the Predictor-Corrector 2nd order hydrodynamic code (PC2) developed at the Center for Research in Water Resources at the University of Texas at Austin from 2005 to 2008. The PC2 code is written in Matlab, which allows rapid mod...

Municipal and regional water use has reduced freshwater inflows to the Nueces Delta. The flow reductions have lead to increased salinities that impair the marsh ecosystem’s functionality. As part of a United States Army Corps of Engineers multi-agency collaboration to restore the Nueces River and its tributaries, we have developed a hydrodynamic mo...

A new method for automatically integrating the results of hydrodynamic models of currents in Texas bays and estuaries with the National Oceanic and Atmospheric Administration’s (NOAA) General NOAA Oil Modeling Environment (GNOME) is presented, along with a system of validation requirements for the integrated models. This work prepares the way for f...

Measurements of stratification and dissolved oxygen (DO) illustrate a hypersaline gravity current with salt loads similar to a desalination plant brine discharge. Over a 48-h sampling period in August 2005, alternating cycles of high-and low-temperature hypersaline water were observed along the bottom of Corpus Christi Bay in Texas, coincident with...

The west campus of Texas A&M University is located in the White Creek watershed and has experienced increases in urbanization in recent years. This urbanization has dramatically impacted White Creek, including bank erosion from higher runoff volumes and peak flows. This study uses HEC-HMS and SWMM models to evaluate the effectiveness of low impact...

Municipal and regional water use has reduced freshwater inflows to the Nueces Delta. The flow reductions have lead to increased salinities that impair the marsh ecosystem's functionality. As part of a United States Army Corps of Engineers multi-agency collaboration to restore the Nueces River and its tributaries, we have developed a hydrodynamic mo...

Hypersaline gravity plumes, such as resulting from desalination discharge into the ocean, an estuary, or coastal embayment, may cause development of hypoxic (low dissolved oxygen, DO) or anoxic (zero DO) regions that are detrimental to the environment. Previously, desalination discharge mixing has been classified by near and far-field zones, with m...

Basin-scale internal waves are inherently nonhydrostatic; however, they are frequently resolved features in three-dimensional hydrostatic lake and coastal ocean models. Comparison of hydrostatic and nonhydrostatic formulations of the Centre for Water Research Estuary and Lake Computer Model provides insight into the similarities and differences bet...

Hypoxia is a common environmental problem that affects many coastal water bodies in the United States. Hypoxia is related to density stratification in the water column which imposes an energy barrier against the transfer of oxygen from the top to the bottom section of the column. In southeast Corpus Christi Bay, strong southeasterly winds force hyp...

Hypoxia is the depletion of dissolved oxygen to levels harmful to aquatic organisms. It is a common environmental problem that affects many coastal water bodies in the United States. A major cause of hypoxia is density stratification in the water column - which imposes an energy barrier against the transfer of oxygen from the top to the bottom of t...

Hydrostatic and non-hydrostatic models were used to simulate the generation of internal surges and associated soliton-like trailing waves from the non-linear steepening of low-frequency basin-scale waves. Results confirmed that the process cannot be modelled using the hydrostatic approximation. A grid-switching strategy was developed to reduce the...