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Full-Text Articles in Engineering

Development And Evaluation Of Seasonal, Continental-Scale Streamflow Forecasts, Elissa Marie Yeates May 2022

Development And Evaluation Of Seasonal, Continental-Scale Streamflow Forecasts, Elissa Marie Yeates

Theses and Dissertations

Methods of forecasting streamflow using atmospheric ensembles and hydrologic routing have greatly improved over the past decades. These forecasts anticipate the timing and magnitude of streamflow peaks, enabling early warning of floods. Recent advances in atmospheric modeling have enabled production of forecasts months ahead, which are less precise but give a useful sense of trends.

The purpose of this study is to produce and evaluate a seasonal streamflow forecast model using a Muskingum routing hydrologic model coupled with runoff from a land surface model, and atmospheric input from a medium-term atmospheric and precipitation model. To evaluate the skill of the …


A Citizen-Science Approach For Urban Flood Risk Analysis Using Data Science And Machine Learning, Candace Agonafir Jan 2022

A Citizen-Science Approach For Urban Flood Risk Analysis Using Data Science And Machine Learning, Candace Agonafir

Dissertations and Theses

Street flooding is problematic in urban areas, where impervious surfaces, such as concrete, brick, and asphalt prevail, impeding the infiltration of water into the ground. During rain events, water ponds and rise to levels that cause considerable economic damage and physical harm. The main goal of this dissertation is to develop novel approaches toward the comprehension of urban flood risk using data science techniques on crowd-sourced data. This is accomplished by developing a series of data-driven models to identify flood factors of significance and localized areas of flood vulnerability in New York City (NYC). First, the infrastructural (catch basin clogs, …


Modeling Watershed Sensitivity To Climate Change In Systems Affected By Discharge Of Mine Tailings, Johnette C. Shockley Dec 2021

Modeling Watershed Sensitivity To Climate Change In Systems Affected By Discharge Of Mine Tailings, Johnette C. Shockley

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

For more than a century, a large volume of gold-mining tailings was deposited in Whitewood Creek and the Belle Fourche River, tributaries to the Cheyenne River in western South Dakota. Much of it still remains, and field and historical evidence indicates continued remobilization of tailings-containing alluvium in these bedrock-dominated channels. Both long-term, natural fluctuations in climate and anthropogenically driven changes can impact regional precipitation, temperature, hydrologic patterns, and ecosystem functions. Such changes have the potential to affect both the transport and distribution of arsenic-laden sediments and mechanical erosion that can undermine the stability of channel-bed and overbank material.

This study …


Effects Of Historical Land-Use Change On Surface Runoff And Flooding In The Amite River Basin, Louisiana, Usa Using Coupled 1d/2d Hec-Ras–Hec-Hms Hydrological Modeling, Alexandre G. H. Cowles Apr 2021

Effects Of Historical Land-Use Change On Surface Runoff And Flooding In The Amite River Basin, Louisiana, Usa Using Coupled 1d/2d Hec-Ras–Hec-Hms Hydrological Modeling, Alexandre G. H. Cowles

LSU Master's Theses

The Amite River Basin is a largely rural watershed spanning parts of four counties in southern Mississippi and seven parishes in southeast Louisiana, with basinwide imperviousness increasing from 0.82% in 1938 to 3.85% in 2016. The Basin has been the subject of significant research interest since catastrophic flooding in 2016 caused 13 deaths and widespread damages. Rapid development in recent decades has led to an expansion of impervious surfaces in Baton Rouge and surrounding areas, encroaching on floodplains and wetlands. At the basin scale, differences in flooding due to impervious cover changes were found to be somewhat limited, particularly along …


Pooling Data Improves Multimodel Idf Estimates Over Median-Based Idf Estimates: Analysis Over The Susquehanna And Florida, Abhishekh Kumar Srivastava, Richard Grotjahn, Paul Aaron Ullrich, Mojtaba Sadegh Apr 2021

Pooling Data Improves Multimodel Idf Estimates Over Median-Based Idf Estimates: Analysis Over The Susquehanna And Florida, Abhishekh Kumar Srivastava, Richard Grotjahn, Paul Aaron Ullrich, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

Traditional multimodel methods for estimating future changes in precipitation intensity, duration, and frequency (IDF) curves rely on mean or median of models’ IDF estimates. Such multimodel estimates are impaired by large estimation uncertainty, shadowing their efficacy in planning efforts. Here, assuming that each climate model is one representation of the underlying data generating process, i.e., the Earth system, we propose a novel extension of current methods through pooling model data: (i) evaluate performance of climate models in simulating the spatial and temporal variability of the observed annual maximum precipitation (AMP), (ii) bias-correct and pool historical and future AMP data of …


Understanding The Effect Of Climate And Hydrometeorological Extremes On Natural And Human-Induced Hydrosystems, Jeongwoo Hwang Jan 2021

Understanding The Effect Of Climate And Hydrometeorological Extremes On Natural And Human-Induced Hydrosystems, Jeongwoo Hwang

Dissertations and Theses

The contemporary hydrosystems of the United States involve a complex combination of natural and modified basins in the presence of changing climate and anthropogenic impacts. An enhanced understanding of the interdependence between climate forcings, human-induced interventions, and water balance in both natural and modified basins are essential for developing reliable and resilient hydrosystems and for better water resources management. In response, this dissertation focuses on investigating the hydroclimatology of natural and modified basins across the contiguous United States. It has three research objectives: (1) to explain flow alterations due to anthropogenic activities, especially dam operations, in modified basins and understand …


River & Estuary Observation Network: Refinement Of Stage Height Sensor Subsystem For Low Cost And High Reliability, W. D. Kirkey, C. B. Fuller, P. O'Brien, P. J. Kirkey, Ahmed Mahmoud, Andrew Ernest, Javier Guerrero Dec 2020

River & Estuary Observation Network: Refinement Of Stage Height Sensor Subsystem For Low Cost And High Reliability, W. D. Kirkey, C. B. Fuller, P. O'Brien, P. J. Kirkey, Ahmed Mahmoud, Andrew Ernest, Javier Guerrero

Civil Engineering Faculty Publications and Presentations

A system comprised of software and on-site measurements is presented for accurately obtaining water stage data from vented or non-vented submersible pressure sensors installed at autonomous stream gauging stations. The system accounts for pressure sensor offset errors, water density, and local gravitational acceleration to produce a stage height reading which is accurate to either ±0.01 ft (±3 mm) or to the accuracy limit of the sensor, whichever is greater. A 2nd order polynomial expression for determination of water density from temperature and salinity is developed and found to be sufficiently accurate for this purpose. Simulated stage measurements performed in the …


Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen Apr 2020

Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen

LSU Doctoral Dissertations

The Mississippi River Delta is threatened by a growing pressure to support large human populations in the United States both with food production, navigation systems, and urban development in the Mississippi River Basin. Nitrate-nitrogen load in the Mississippi River, up to 100 Tg N yr-1 from agricultural and urban runoff, leads to phytoplankton blooms and hypoxia across the Louisiana continental shelf, creating dead zones of low dissolved oxygen threatening a significant commercial fishery. Along the coast and river corridors, floodplain ecosystems have the capacity to retain and remove nitrate. This dissertation explores the role of productive, actively growing coastal …


Probabilistic Approach To Water, Sediment, And Nutrient Connectivity For Advancing Watershed Modelling, David Tyler Mahoney Jan 2020

Probabilistic Approach To Water, Sediment, And Nutrient Connectivity For Advancing Watershed Modelling, David Tyler Mahoney

Theses and Dissertations--Civil Engineering

The goal of this dissertation is to represent the spatial and temporal domains of water, sediment, and nutrient flux and pathways within fluvial and watershed settings. To complete this goal, we integrate connectivity theory into watershed model structures to simulate water, sediment, and nutrient movement at the fundamental unit they occur. Fluvial-based sediment and nutrient flux is an important driver of global sediment and nutrient budgets, and the quantification of which serves as an ongoing challenge to limnologists, engineers, and watershed managers. Watershed models have been richly developed over the past century, but are currently restrained by problems related to …


Civil Engineering Research In Ireland 2020: Conference Proceedings, Kieran Ruane, Vesna Jaksic, Bidisha Ghosh, Magdalena Hajdukiewicz, Ciaran Hanley, Niall Holmes, Jennifer Keenahan, Zili Li, Patrick Mcgetrick, Ted Mckenna, Mary Moloney, Vikram Pakrashi, Niamh Power Jan 2020

Civil Engineering Research In Ireland 2020: Conference Proceedings, Kieran Ruane, Vesna Jaksic, Bidisha Ghosh, Magdalena Hajdukiewicz, Ciaran Hanley, Niall Holmes, Jennifer Keenahan, Zili Li, Patrick Mcgetrick, Ted Mckenna, Mary Moloney, Vikram Pakrashi, Niamh Power

Books

Civil Engineering Research in Ireland 2020: Conference Proceedings.


Assessing Simulated Transmissivity In Numerical Flow Models Of Complex Hydrogeology, Afan Tarar May 2019

Assessing Simulated Transmissivity In Numerical Flow Models Of Complex Hydrogeology, Afan Tarar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Accurately extracting a meaningful transmissivity, a target value within one order of magnitude of field estimates, in numerical models poses a significant challenge when modeling complex groundwater systems. Aquifer transmissivity is directly proportional to the aquifer thickness and the estimated aquifer hydraulic conductivity. In complex geologic conditions (especially in fractured systems) with multiple heterogeneous and anisotropic hydrogeologic units, transmissivity can vary over several orders of magnitude.

To extract a meaningful value of transmissivity from a numerical model, a simple five-layer MODFLOW model was constructed. Each layer in the model was assigned a fixed hydraulic conductivity and thickness. The model simulates …


Assessing Data Availability And Research Reproducibility In Hydrology And Water Resources, James H. Stagge, David E. Rosenberg, Adel M. Abdallah, Hadia Akbar, Nour A. Atallah, Ryan James Feb 2019

Assessing Data Availability And Research Reproducibility In Hydrology And Water Resources, James H. Stagge, David E. Rosenberg, Adel M. Abdallah, Hadia Akbar, Nour A. Atallah, Ryan James

Civil and Environmental Engineering Faculty Publications

There is broad interest to improve the reproducibility of published research. We developed a survey tool to assess the availability of digital research artifacts published alongside peer-reviewed journal articles (e.g. data, models, code, directions for use) and reproducibility of article results. We used the tool to assess 360 of the 1,989 articles published by six hydrology and water resources journals in 2017. Like studies from other fields, we reproduced results for only a small fraction of articles (1.6% of tested articles) using their available artifacts. We estimated, with 95% confidence, that results might be reproduced for only 0.6% to 6.8% …


Hydroclimate Drivers And Atmospheric Dynamics Of Floods, Nasser Najibi Jan 2019

Hydroclimate Drivers And Atmospheric Dynamics Of Floods, Nasser Najibi

Dissertations and Theses

Our preliminary survey showed that most of the recent flood-related studies did not formally explain the physical mechanisms of long-duration and large-peak flood events that can evoke substantial damages to properties and infrastructure systems. These studies also fell short of fully assessing the interactions of coupled ocean-atmosphere and land dynamics which are capable of forcing substantial changes to the flood attributes by governing the exceeding surface flow regimes and moisture source-sink relationships at the spatiotemporal scales important for risk management. This dissertation advances the understanding of the variability in flood duration, peak, volume, and timing at the regional to the …


Prediction Of Flood Hydrograph In Small River Catchments Using System Modelling Approach, Ahmed Nasr, Zeinab Bedri, Loreta Ramanauske Aug 2018

Prediction Of Flood Hydrograph In Small River Catchments Using System Modelling Approach, Ahmed Nasr, Zeinab Bedri, Loreta Ramanauske

Conference papers

Floods remain to be one of the natural catastrophic disasters with serious adverse social and economic implications on individuals and communities all around the world. In Ireland, frequency of flood events have increased dramatically during the last forty years and is expected to continue to rise primarily due to changes in rainfall and temperature patterns as a result of the global climate change. Small river catchments are usually vulnerable to different types of flooding particularly those associated with “monster” rainfall events, which are characterised by short durations and high intensities. Therefore accurate prediction of flood hydrographs resulting from these rainfall …


The Soil Moisture Velocity Equation, Fred L. Ogden, Myron B. Allen, Wencong Lai, Jianting Zhu, Mookwon Seo, Craig C. Douglas, Cary A. Talbot Jun 2017

The Soil Moisture Velocity Equation, Fred L. Ogden, Myron B. Allen, Wencong Lai, Jianting Zhu, Mookwon Seo, Craig C. Douglas, Cary A. Talbot

Publications

Numerical solution of the one-dimensional Richards' equation is the recommended method for coupling groundwater to the atmosphere through the vadose zone in hyperresolution Earth system models, but requires fine spatial discretization, is computationally expensive, and may not converge due to mathematical degeneracy or when sharp wetting fronts occur. We transformed the one-dimensional Richards' equation into a new equation that describes the velocity of moisture content values in an unsaturated soil under the actions of capillarity and gravity. We call this new equation the Soil Moisture Velocity Equation (SMVE). The SMVE consists of two terms: an advection-like term that accounts for …


Impact Of Using Spatially Distributed Soils Information On Flood Hydrograph Simulation With Hec-Hms, Matthew J. Nelson May 2017

Impact Of Using Spatially Distributed Soils Information On Flood Hydrograph Simulation With Hec-Hms, Matthew J. Nelson

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Hydrologic rainfall-runoff models employ numerical equations to simulate the soil absorption of rainfall and resulting runoff. A number of methods have been developed to model these processes, but the parameters used to define these methods can be difficult to directly measure due to the variable nature of soil properties. They often rely on estimation of hydraulic and hydrologic parameters and calibration to produce accurate results.

A challenge with runoff method parameterization is the need for oversimplification using a lumped modeling approach. While distributed hydrologic modeling techniques are now available, distributed runoff methods are limited in use due to the tradition …


Laboratory Exercise – Calculating Runoff Over Land Parcels, Wade Bozeman, Steven Evans, Ryan Selee Jan 2017

Laboratory Exercise – Calculating Runoff Over Land Parcels, Wade Bozeman, Steven Evans, Ryan Selee

Engineering Applications of GIS - Laboratory Exercises

When developing land, most municipalities will require that all runoff from the site be retained on site or flow into a storm water conveyance system. In the near future, new regulation will require that all runoff be retained on site. For this reason, it is important to know how much runoff can be expected to flow over a potential development site. In this lab, you will use ArcMap ModelBuilder to predict the amount of flow which can be expected over a land parcel in a storm event.


Laboratory Exercise: Calculating Hobble Creek 100 Year Flow Using Arcmap, Micklane Farmer, Saul Ramirez, Riley Vane Jan 2017

Laboratory Exercise: Calculating Hobble Creek 100 Year Flow Using Arcmap, Micklane Farmer, Saul Ramirez, Riley Vane

Engineering Applications of GIS - Laboratory Exercises

GIS is used extensively in watershed analysis. In previous labs, students have determined a watershed from DEM data. Calculating flow can be very useful in many engineering aspects. With the correct data, GIS can be used to develop a hydrologic model to calculate the flow from a watershed. The purpose of this lab is to develop a model to calculate the flow for the Hobble Creek 100 year event.


Case Study For Guided Project In Stochastic Hydrology, Meghna Babbar-Sebens Jan 2017

Case Study For Guided Project In Stochastic Hydrology, Meghna Babbar-Sebens

All ECSTATIC Materials

Attached are two guided project activities for hydrology and climate data of Eagle Creek Watershed, Indiana, USA. The zip files have flow and precipitation datasets at daily, monthly, and annual time scales.


Using An Object And Pattern Oriented Approach To Hydrological Modelling Teaching And Research, R.W. Vervoort, J.H.A. Guillaume, T.F.A Bishop, D. Kundu, F.F. Van Ogtrop Jul 2016

Using An Object And Pattern Oriented Approach To Hydrological Modelling Teaching And Research, R.W. Vervoort, J.H.A. Guillaume, T.F.A Bishop, D. Kundu, F.F. Van Ogtrop

International Congress on Environmental Modelling and Software

Introducing hydrological modelling in undergraduate teaching is challenging, and some of this is related to the decline in STEM knowledge in students. Enabling students to confidently work with a range of hydrological models remains difficult, particularly if the goal is to make students understand the modelling process and model structures. The limited literature points to a number of educational tools that have been developed, falling into three classes: magical box fully developed GUIs with little insight into model operation; highly theoretical command line linear reservoir and unit hydrograph tools; and model tools focusing on one single model structure. Given the …


Evaluation Of Low-Cost Low Impact Development Practices In Southwest Florida For The Control Of Urban Runoff, Laura Kathren Rankin Nov 2015

Evaluation Of Low-Cost Low Impact Development Practices In Southwest Florida For The Control Of Urban Runoff, Laura Kathren Rankin

USF Tampa Graduate Theses and Dissertations

Stormwater management is required due to development and alteration of the natural environment. It is heavily regulated in Florida and at the national level. Over the last two decades, Low Impact Development (LID) has been promoted as a sustainable and environmentally friendly method of controlling urban runoff. Case studies, provided in Chapter 2, show that LIDs can restore watershed hydrology by balancing the water budget. The difference in runoff between pre-development and post-development appears to increase with soil perviousness. However, the potential for mitigating the impacts of urbanization through runoff reduction is also greater for pervious, sandy soils that dominate …


Essays On The Quantification And Propagation Of Uncertainty In Climate Change Impact Assessments For Water Resource Systems, Scott Steinschneider Aug 2014

Essays On The Quantification And Propagation Of Uncertainty In Climate Change Impact Assessments For Water Resource Systems, Scott Steinschneider

Doctoral Dissertations

Sustainable water resources planning and management under climate change requires a proper treatment of uncertainties that emerge in an impacts analysis. A primary source of this uncertainty originates from the difficulties in projecting how anthropogenic greenhouse gas emissions will evolve over time and influence the climate system at regional and local scales. However, other sources of uncertainty, such as errors in modeling hydrologic response to climate and the influences of internal climate variability, compound the effects of climate change uncertainty and further obscure our understanding of water resources performance under future climate conditions. This work presents an approach to quantify …


Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou Jul 2014

Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou

Open Access Theses

Understanding the hydrologic controls that regulate outflow from free and managed subsurface drainage systems during drainage events can offer improved insight on the overall functioning and effectiveness of the systems so that they can be better managed or retrofitted to increase their environmental benefits. This study used drainage, precipitation, water table, and soil moisture data from a monitoring site located in east central Indiana to investigate the event hydrology of 22 drainage events in free and managed subsurface drainage systems. Relationships between event drainage volume, drain flow hydrograph metrics, column soil moisture, water table depth, and precipitation characteristics were explored …


Apex-Cute: An Auto-Calibration And Uncertainty Analysis Tool For The Apex Model, Xiuying Wang, Haw Yen Jun 2014

Apex-Cute: An Auto-Calibration And Uncertainty Analysis Tool For The Apex Model, Xiuying Wang, Haw Yen

International Congress on Environmental Modelling and Software

The Agricultural Policy Environmental eXtender - auto-Calibration and UncerTainty Estimator (APEX-CUTE) was developed as an open-source tool which enhances the accessibility for APEX users to conduct potentially tedious calibration work on the APEX model. The role of uncertainty analysis should be taken as an independent supporting package to extend the capability in further analytical purposes. This version of APEX-CUTE incorporates relevant functions of uncertainty analysis flexibly. Users have options to include designated uncertainty sources such as input and/or measurement errors during the calibration process. APEX-CUTE is not only the comprehensive package in performing model calibration on APEX, but it can …


The Data Processing Inequality And Environmental Model Prediction, Steven V. Weijs Jun 2014

The Data Processing Inequality And Environmental Model Prediction, Steven V. Weijs

International Congress on Environmental Modelling and Software

Prediction in environmental systems, such as hydrological streamflow prediction, is a challenging task. Although on a small scale, many of the physical processes are well described, accurate predictions of macroscopical (e.g. catchment scale) behavior with a bottom-up mechanistic approach often remains elusive. On the other hand, conceptual or purely statistical models fitted to data often perform surprisingly well for prediction. The data processing inequality, from the field of information theory, says that processing data with statistical procedures can only decrease, and not increase the information content of the data. This seems to contradict the intuition that our knowledge of physical …


Long-Term Evaluation Of Norris Reservoir Operation Under Climate Change, Joseph Patton Rungee Ii May 2014

Long-Term Evaluation Of Norris Reservoir Operation Under Climate Change, Joseph Patton Rungee Ii

Masters Theses

This study aimed to address the potential long-term effects of future climate change on the Tennessee Valley Authority’s (TVA’s) operation policy for Norris Reservoir. The Community Earth System Model 1.0 (CESM1.0), a general circulation model (GCM) accessible through the Intergovernmental Panel on Climate Change’s (IPCC’s) Coupled Model Intercomparison Project Phase 5 (CMIP5), with the Representative Concentration Pathway 4.5 (RCP4.5) was used to obtain projected precipitation and temperature data for three future climate scenarios, 2030’s, 2050’s, and 2070’s. Three hydrologic models were individually calibrated on 30 years of observed runoff data and combined utilizing linear programming to consider the strengths of …


Water At The Centre Of Environmental Issues – Research At The Ucd Dooge Centre For Water Resources Research, Zeinab Bedri, Eva M. Mockler, Michael Bruen, Yaqian Zhao, Pj Purcell, John O'Sullivan, M. Alsaji, Aisling Corkery, Liam Doherty, M. Dzakpasu, M. Martins, A. Rymszewicz, L. Willuwet Apr 2014

Water At The Centre Of Environmental Issues – Research At The Ucd Dooge Centre For Water Resources Research, Zeinab Bedri, Eva M. Mockler, Michael Bruen, Yaqian Zhao, Pj Purcell, John O'Sullivan, M. Alsaji, Aisling Corkery, Liam Doherty, M. Dzakpasu, M. Martins, A. Rymszewicz, L. Willuwet

Conference papers

Since 1988, the UCD Dooge Centre for Water Resources Research has been conducting research in a wide range of water topics including hydraulics, hydrology, coastal dynamics and wastewater with an emphasis on multi-disciplinary collaboration. This paper presents an overview of this research, both past and present, and provides an outlook to the future research directions of the Centre.


An Investigation Into The Water Budget And The Management Of The Snake River System, John Whitney Hildreth Dec 2013

An Investigation Into The Water Budget And The Management Of The Snake River System, John Whitney Hildreth

Boise State University Theses and Dissertations

Future climate change poses a major conceptual challenge to the availability of water resources due to the uncertainty involved with changes to the hydrologic cycle. Over the past decades, observed warming temperatures across the Western United Sates have shown significant impacts on river basin scale hydrology. This research uses physically based modeling tools to assess the hydrologic impacts of climate change in the Snake River Basin. Physically based hydrologic modeling studies of future climate do not typically take into account interactions between groundwater and surface water. To account for these interactions, the Variable Infiltration Capacity model is coupled with the …


Water Resources Planning And Management - Michigan Technological University, Houghton, David Watkins Oct 2013

Water Resources Planning And Management - Michigan Technological University, Houghton, David Watkins

All ECSTATIC Materials

Graduate course in water resources planning and management offered at Michigan Technological University, Houghton in Fall 2013.


Hydraulic Impact Of Porosity Distribution And Hydrologic Characterization Of Porous Pavements, William Martin Aug 2013

Hydraulic Impact Of Porosity Distribution And Hydrologic Characterization Of Porous Pavements, William Martin

All Dissertations

This research focused on the hydrologic characterization of porous pavement and pavement properties that can affect its hydraulic behavior. The first of these properties investigated was the presence of a vertical porosity distribution which can significantly impact the infiltration rate. A method utilizing image analysis was tested and experimentally verified. The representative elemental area (REA) was needed for this imaging method and was found to be 83.9 cm2 (13 in2). To convert the porosity distribution into a permeability distribution the relationship between porosity and permeability was found using homogenous samples. From the resulting permeability distribution an effective permeability was found …