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Full-Text Articles in Engineering

Assessment Of Surface Soil Moisture Using High-Resolution Multi-Spectral Imagery And Artificial Neural Networks, Leila Hassan-Esfahani, Alfonso Torres-Rua, Austin Jensen, Mac Mckee Nov 2016

Assessment Of Surface Soil Moisture Using High-Resolution Multi-Spectral Imagery And Artificial Neural Networks, Leila Hassan-Esfahani, Alfonso Torres-Rua, Austin Jensen, Mac Mckee

Leila Hassan-Esfahani

Many crop production management decisions can be informed using data from high-resolution aerial images that provide information about crop health as influenced by soil fertility and moisture. Surface soil moisture is a key component of soil water balance, which addresses water and energy exchanges at the surface/atmosphere interface; however, high-resolution remotely sensed data is rarely used to acquire soil moisture values. In this study, an artificial neural network (ANN) model was developed to quantify the effectiveness of using spectral images to estimate surface soil moisture. The model produces acceptable estimations of surface soil moisture (root mean square error (RMSE) = …


The Impact Of Slit And Detention Dams On Debris Flow Control Using Gstars 3.0, Leila Hassan-Esfahani, Mohammad Ebrahim Banihabib Nov 2016

The Impact Of Slit And Detention Dams On Debris Flow Control Using Gstars 3.0, Leila Hassan-Esfahani, Mohammad Ebrahim Banihabib

Leila Hassan-Esfahani

Sedimentation, Modeling, GSTARS3.0, Debris flow, Slit dam, Detention dam


Assessment Of Surface Soil Moisture Using High-Resolution Multi-Spectral Imagery And Artificial Neural Networks, Leila Hassan-Esfahani, Alfonso Torres-Rua, Austin Jensen, Mac Mckee Nov 2016

Assessment Of Surface Soil Moisture Using High-Resolution Multi-Spectral Imagery And Artificial Neural Networks, Leila Hassan-Esfahani, Alfonso Torres-Rua, Austin Jensen, Mac Mckee

Leila Hassan-Esfahani

Many crop production management decisions can be informed using data from high-resolution aerial images that provide information about crop health as influenced by soil fertility and moisture. Surface soil moisture is a key component of soil water balance, which addresses water and energy exchanges at the surface/atmosphere interface; however, high-resolution remotely sensed data is rarely used to acquire soil moisture values. In this study, an artificial neural network (ANN) model was developed to quantify the effectiveness of using spectral images to estimate surface soil moisture. The model produces acceptable estimations of surface soil moisture (root mean square error (RMSE) = …


Differences In Nutrient And Metal Uptake Among Plant Species In Stormwater Bioretention Systems., M. R. Borecki, Ryan Dupont, Joan E. Mclean Mar 2016

Differences In Nutrient And Metal Uptake Among Plant Species In Stormwater Bioretention Systems., M. R. Borecki, Ryan Dupont, Joan E. Mclean

Civil and Environmental Engineering Faculty Publications

No abstract provided.


Bioenergy From Wastewater-Based Biomass, Ronald C. Sims, Sean K. Bedingfield, Reese Thompson, Judith L. Sims Jan 2016

Bioenergy From Wastewater-Based Biomass, Ronald C. Sims, Sean K. Bedingfield, Reese Thompson, Judith L. Sims

Biological Engineering Faculty Publications

The U.S. Department of Energy (DOE) has stated that biomass is the only renewable resource that can supplant petroleum-based liquid transportation fuels in the near term. Wastewater is beginning to be viewed as a potential resource that can be exploited for biomass production and conversion to bioenergy. We suggest that using wastewater from municipalities and industries as a resource for cultivating biomass and combining wastewater treatment with the production of biomass for bioenergy would provide benefits to both industries. Two waste-based biomass production systems that currently have large nationwide infrastructures include: (1) wastewater treatment systems that can be used to …


Dehalococcoides Abundance And Alternate Electron Acceptor Effects On Large, Flow-Through Trichloroethene Dechlorinating Columns, Babur S. Mirza, Darwin L. Sorensen, Ryan Dupont, Joan E. Mclean Nov 2015

Dehalococcoides Abundance And Alternate Electron Acceptor Effects On Large, Flow-Through Trichloroethene Dechlorinating Columns, Babur S. Mirza, Darwin L. Sorensen, Ryan Dupont, Joan E. Mclean

Civil and Environmental Engineering Faculty Publications

Trichloroethene (TCE) in groundwater is a major health concern and biostimulation/bioaugmentation-based strategies have been evaluated to achieve complete reductive dechlorination with varying success. Different carbon sources were hypothesized to stimulate different extents of TCE reductive dechlorination. Ecological conditions that developed different dechlorination stages were investigated by quantitating Dehalococcoides 16S rRNA (Dhc) and reductive dehalogenase gene abundance, and by describing biogeochemical properties of laboratory columns in response to this biostimulation. Eight large columns (183 cm × 15.2 cm), packed with aquifer material from Hill AFB, Utah, that were continuously fed TCE for 7.5 years. Duplicate columns were biostimulated with whey or …


Development Of A Decision-Making Methodology To Design A Water Quality Monitoring Network, J. Keum, Jagath J. Kaluarachchi Jun 2015

Development Of A Decision-Making Methodology To Design A Water Quality Monitoring Network, J. Keum, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

The number of water quality monitoring stations in the USA has decreased over the past few decades. Scarcity of observations can easily produce prediction uncertainty due to unreliable model calibration. An effective water quality monitoring network is important not only for model calibration and water quality prediction but also for resources management. Redundant or improperly located monitoring stations may cause increased monitoring costs without improvement to the understanding of water quality in watersheds. In this work, a decision-making methodology is proposed to design a water quality monitoring network by providing an adequate number of monitoring stations and their approximate locations …


Biostimulation And Bioaugmentation To Enhance Reductive Dechlorination Of Tce In A Long-Term Flow Through Column Study, Joan E. Mclean, Jared Ervin, Jing Zhou, Darwin L. Sorensen, Ryan Dupont May 2015

Biostimulation And Bioaugmentation To Enhance Reductive Dechlorination Of Tce In A Long-Term Flow Through Column Study, Joan E. Mclean, Jared Ervin, Jing Zhou, Darwin L. Sorensen, Ryan Dupont

Civil and Environmental Engineering Faculty Publications

Large laboratory columns (15.2 cm diameter, 183 cm long) were fed with groundwater containing trichloroethylene (TCE), were biostimulated and bioaugmented, and were monitored for over 7.5 years. The objective of the study was to observe how the selection of the carbon and energy source, i.e., whey, Newman Zone® standard surfactant emulsified oil and Newman Zone nonionic surfactant emulsified oil, affected the rate and extent of dechlorination. Column effluent was monitored for TCE and its degradation products, redox indicators (nitrate-N, Fe(II), sulfate), and changes in iron mineralogy. Total bacteria and Dehalococcoides mccartyi strains were quantified using q-PCR. Complete dechlorination was only …


Particulate-Matter Emission Estimates From Agricultural Spring-Tillage Operations Using Lidar And Inverse Modeling, Kori D. Moore, Michael D. Wojcik, Randy S. Martin, Christian C. Marchant, D. S. Jones, W. J. Bradford, G. E. Bingham, R L. Pfeiffer, J. H. Prueger, J. L. Hatfield Mar 2015

Particulate-Matter Emission Estimates From Agricultural Spring-Tillage Operations Using Lidar And Inverse Modeling, Kori D. Moore, Michael D. Wojcik, Randy S. Martin, Christian C. Marchant, D. S. Jones, W. J. Bradford, G. E. Bingham, R L. Pfeiffer, J. H. Prueger, J. L. Hatfield

Civil and Environmental Engineering Faculty Publications

Particulate-matter (PM) emissions from a typical spring agricultural tillage sequence and a strip–till conservation tillage sequence in California’s San Joaquin Valley were estimated to calculate the emissions control efficiency (ηη) of the strip–till conservation management practice (CMP). Filter-based PM samplers, PM-calibrated optical particle counters (OPCs), and a PM-calibrated light detection and ranging (LIDAR) system were used to monitored upwind and downwind PM concentrations during May and June 2008. Emission rates were estimated through inverse modeling coupled with the filter and OPC measurements and through applying a mass balance to the PM concentrations derived from LIDAR data. Sampling irregularities and errors …


Remediation Of Polycyclic Aromatic Hydrocarbons In Soil Using Hemoglobin-Catalytic Mechanism, Guyoung Kang, Kapsung Park, Jaechang Cho, David King Stevens, Namhyun Chung Jan 2015

Remediation Of Polycyclic Aromatic Hydrocarbons In Soil Using Hemoglobin-Catalytic Mechanism, Guyoung Kang, Kapsung Park, Jaechang Cho, David King Stevens, Namhyun Chung

Civil and Environmental Engineering Faculty Publications

It is suggested in this paper that recalcitrant organopollutants can be degraded efficiently by a hemoglobin-catalytic reaction in the presence of hydrogen peroxide (i.e., H2O2). The catalytic mechanism was studied with 5-aminosalicylic acid (5-ASA) as a compound for oxidation. Various evidence suggests that the catalytic mechanism is very similar to those of horseradish peroxidase and lignin peroxidase. The catalytic intermediates are known to oxidize various chemicals, indicating that the intermediates of hemoglobin can nonspecifically degrade many different types of organopollutants. To prove the hypothesis, an attempt was made to remediate polycyclic aromatic hydrocarbon (PAH)-contaminated field soil. The results showed that …


Can Suspended Fine Sediment Transport In Shallow Lakes Be Predicted Using Mvrvm With Limited Observations?, H. A. Batt Ph.D., David King Stevens Jan 2015

Can Suspended Fine Sediment Transport In Shallow Lakes Be Predicted Using Mvrvm With Limited Observations?, H. A. Batt Ph.D., David King Stevens

Civil and Environmental Engineering Faculty Publications

The study of sediment transport in water natural bodies is a challenging task. There have been several attempts to describe sediment mathematically using hydraulic characteristics of water bodies. Most researchers who developed empirical formulas to describe sediment transport performed laboratory experiments with assumptions that did not take into account variations of hydraulic parameters and the fine sediment sizes that are part of this phenomenon. Recently, new approaches for studying sediment transport have been developed involving the use of machine-learning algorithms that have proven accuracy and efficiency in predicting sediment transport. A novel machinelearning method, the Multivariate Relevance Vector Machine (MVRVM), …


Approaches For Studying Fish Production: Do River And Lake Researchers Have Different Perspectives?, Wayne A. Wurtsbaugh, Nicholas A. Heredia, Brian G. Laub, Christy S. Meredith, Harrison E. Mohn, Sarah E. Null, David A. Pluth, Brett B. Roper, W. Carl Saunders, David King Stevens, Richard H. Walker, Kit Wheeler Sep 2014

Approaches For Studying Fish Production: Do River And Lake Researchers Have Different Perspectives?, Wayne A. Wurtsbaugh, Nicholas A. Heredia, Brian G. Laub, Christy S. Meredith, Harrison E. Mohn, Sarah E. Null, David A. Pluth, Brett B. Roper, W. Carl Saunders, David King Stevens, Richard H. Walker, Kit Wheeler

Civil and Environmental Engineering Faculty Publications

Biased perspectives of fisheries researchers may hinder scientific progress and effective management if limiting factors controlling productivity go unrecognized. We investigated whether river and lake researchers used different approaches when studying salmonid production and whether any differences were ecologically supported. We assessed 564 peer-reviewed papers published between 1966 and 2012 that studied salmonid production or surrogate variables (e.g., abundance, growth, biomass, population) and classified them into five major predictor variable categories: physical habitat, fertility (i.e., nutrients, bottom-up), biotic, temperature, and pollution. The review demonstrated that river researchers primarily analyzed physical habitat (65% of studies) and lake researchers primarily analyzed fertility …


How To Utilize Relevance Vectors To Collect Required Data For Modeling Water Quality Constitu-Ents, And Fine Sediment In Natural Systems? Case Study: Mud Lake, Idaho, Hussein Aly Batt, David King Stevens Jun 2014

How To Utilize Relevance Vectors To Collect Required Data For Modeling Water Quality Constitu-Ents, And Fine Sediment In Natural Systems? Case Study: Mud Lake, Idaho, Hussein Aly Batt, David King Stevens

Civil and Environmental Engineering Faculty Publications

The development of monitoring programs for water quality and habitat assessment in surface waters is an ongoing challenge because of inherent difficulties in determining the effective spatial and temporal distribution of sites and trips. Recent advances in statistical learning theory, in which system characteristics are learned from data, point to the possibility of using the information content of data to shed light on monitoring results that provide sensitive and independent results. One of those techniques, multivariate relevance vector machines (MVRVM), creates as part of its algorithm subsets of a data set, called relevant vectors (RVs), that are most relevant for …


The Impact Of Slit And Detention Dams On Debris Flow Control Using Gstars 3.0, Leila Hassan-Esfahani, Mohammad Ebrahim Banihabib Jan 2014

The Impact Of Slit And Detention Dams On Debris Flow Control Using Gstars 3.0, Leila Hassan-Esfahani, Mohammad Ebrahim Banihabib

Civil and Environmental Engineering Faculty Publications

Sedimentation, Modeling, GSTARS3.0, Debris flow, Slit dam, Detention dam


Ozone Photochemistry In A Natural Gas Basin During Winter: Simulations Of Results From The 2012 Utah Basin Winter Ozone Study, P. M. Edwards, K. J. Akin, J. Degouw, W P. Dubé, J. Gillman, D. Helmig, J S. Holloway, B. Lener, R. Mclaren, D. D. Parrish, J. Peischl, J. M. Roberts, T. B. Ryerson, Randy S. Martin, C. Warneke, E. J. Williams, C. J. Young, S. S. Brown Sep 2013

Ozone Photochemistry In A Natural Gas Basin During Winter: Simulations Of Results From The 2012 Utah Basin Winter Ozone Study, P. M. Edwards, K. J. Akin, J. Degouw, W P. Dubé, J. Gillman, D. Helmig, J S. Holloway, B. Lener, R. Mclaren, D. D. Parrish, J. Peischl, J. M. Roberts, T. B. Ryerson, Randy S. Martin, C. Warneke, E. J. Williams, C. J. Young, S. S. Brown

Civil and Environmental Engineering Faculty Publications

The Uintah Basin in northeastern Utah, a region of intense oil and gas extraction, experienced ozone (O3) concentrations above levels harmful to human health for multiple days during the winters of 2009–2010 and 2010–2011. These wintertime O3 pollution episodes occur during cold, stable periods when the ground is snow-covered, and have been linked to emissions from the oil and gas extraction process. The Uintah Basin Winter Ozone Study (UBWOS) was a field intensive in early 2012, whose goal was to address current uncertainties in the chemical and physical processes that drive wintertime O3 production in regions of oil and gas …


Volatilization Of Trichloroethylene From Trees And Soil: Measurement And Scaling Approaches, William J. Doucette, H. Klein, J. Chard, Ryan Dupont, W. Plaehn, Bruce Bugbee Jun 2013

Volatilization Of Trichloroethylene From Trees And Soil: Measurement And Scaling Approaches, William J. Doucette, H. Klein, J. Chard, Ryan Dupont, W. Plaehn, Bruce Bugbee

Civil and Environmental Engineering Faculty Publications

Trichloroethylene (TCE) volatilization from leaves, trunk, and soil was measured to assess the significance of these pathways from phytoremediation sites at Travis and Fairchild Air Force Bases. Measurements were scaled temporally and spatially to estimate the annual volatilization of TCE at the Travis (0.82 ± 0.51 kg/yr) and Fairchild sites (0.014 ± 0.008 kg/yr). Volatilization was primarily through the leaf (0.34 ± 0.16 kg/yr at Travis and 0.01 ± 0.06 kg/yr at Fairchild) and soil (0.48 ± 0.36 kg/yr at Travis, 0.003 ± 0.002 kg/yr at Fairchild) pathways. The larger volatilization estimate at Travis was expected because of the site's …


Ammonia Measurements And Emissions From A California Dairy Using Point And Remote Sensors, Kori D. Moore, E. Young, C. Gurell, Michael D. Wojcik, Randy S. Martin, G. E. Bingham, R. L. Pfeiffer, J. H. Prueger, J. L. Hatfield Dec 2012

Ammonia Measurements And Emissions From A California Dairy Using Point And Remote Sensors, Kori D. Moore, E. Young, C. Gurell, Michael D. Wojcik, Randy S. Martin, G. E. Bingham, R. L. Pfeiffer, J. H. Prueger, J. L. Hatfield

Civil and Environmental Engineering Faculty Publications

Ammonia (NH3) is an important trace gas species in the atmosphere that can have negative impacts on human, animal, and ecosystem health. Agriculture has been identified as the largest source of NH3, specifically livestock operations. NH3 emissions from a commercial dairy in California were investigated during June 2008. Cattle were held in open-lot pens, except for young calves in hutches with shelters. Solid manure was stored in the open-lot pens. Liquid manure from feed lanes was passed through a solids settling basin and stored in a holding pond. Passive sensors and open-path Fourier transform infrared spectrometers (OP-FTIR) were deployed around …


A Comparison Of Traditional And Bayesian Statistical Models In Fluvial Sediment Transport, Mark L. Schmelter, David King Stevens Aug 2012

A Comparison Of Traditional And Bayesian Statistical Models In Fluvial Sediment Transport, Mark L. Schmelter, David King Stevens

Civil and Environmental Engineering Faculty Publications

The characterization of sediment transport is an important problem that has been actively studied for some time. Numerous approaches have been demonstrated in the literature, including mechanistic models, probabilistic arguments, machine learning algorithms, and empirical formulations. Most implementations of sediment transport relations are deterministic in nature and require the specification of model parameters. These parameters are traditionally assumed fixed (i.e., a single value), and subsequent predictions are not necessarily representative because of uncertainty because they are fixed (i.e., a line). In this paper, a Bayesian statistical sediment transport model is presented, and its ability to infer critical shear values from …


A Modeling Approach To Assessing The Effect Of Multiple Lakes In Sequence On Nutrient Transport, Dave M. Epstein, Bethany T. Neilson, Keli J. Goodman, David King Stevens, Wayne A. Wurtsbaugh Jun 2012

A Modeling Approach To Assessing The Effect Of Multiple Lakes In Sequence On Nutrient Transport, Dave M. Epstein, Bethany T. Neilson, Keli J. Goodman, David King Stevens, Wayne A. Wurtsbaugh

Civil and Environmental Engineering Faculty Publications

The effects of a single lake on downstream water chemistry may be compounded by the presence of additional lakes within the watershed, augmenting or negating the effects of the first lake. Multiple, linked lakes are a common feature of many watersheds and these resemble reactors in series often studied in engineering. The effects of multiple lakes in series on nutrient transport are largely unexplored. We populated and calibrated a simple lake model to investigate the role of a sub-alpine lake (Bull Trout Lake (BTL), Rocky Mountains, USA) on the transport of the macronutrients during the summer of 2008. Further, we …


Urban Particulate Matter Activates Akt In Human Lung Cells, T. L. Watterson, B. Hamilton, Randy S. Martin, R. A. Coloumb Jr. Jan 2012

Urban Particulate Matter Activates Akt In Human Lung Cells, T. L. Watterson, B. Hamilton, Randy S. Martin, R. A. Coloumb Jr.

Civil and Environmental Engineering Faculty Publications

The normally picturesque Cache Valley in northern Utah is frequently reported to have the worst particulate (PM) air pollution in the United States. Numerous epidemiological studies conducted elsewhere have associated PM exposure to a variety of cardiovascular diseases and early mortality. We have previously shown that Cache Valley PM (CVPM) is pro-inflammatory, through a variety of mechanisms involving the release of inflammatory cytokines, unfolded protein response, ER stress, and C-reactive protein (CRP). This study was undertaken to determine whether Cache Valley PM (CVPM) would activate Akt, an upstream mechanism common to these events. Human lung (BEAS-2B) cells were treated with …


Bayesian Sediment Transport Model For Unisize Bed Load, Mark L. Schmelter, Mevin B. Hooten, David King Stevens Nov 2011

Bayesian Sediment Transport Model For Unisize Bed Load, Mark L. Schmelter, Mevin B. Hooten, David King Stevens

Civil and Environmental Engineering Faculty Publications

Fluvial sediment transport studies have long underscored the difficulty in reliablyestimating transport model parameters, collecting accurate observations, and makingpredictions because of measurement error, natural variability, and conceptual modeluncertainty. Thus, there is a need to identify modeling frameworks that accommodate theserealities while incorporating functional relationships, providing probability-basedpredictions, and accommodating for conceptual model discrimination. Bayesian statisticalapproaches have been widely used in a number of disciplines to accomplish just this, yetapplications in sediment transport are few. In this paper we propose and demonstrate aBayesian statistical approach to a simple sediment transport problem as a means toovercome some of these challenges. This approach provides …


Estimation Of Dariy Particulate Matter Emission Rates By Lidar And Inverse Modeling, C. C. Marchant, Kori D. Moore, Michael D. Wojcik, Randy S. Martin, R L. Pfeiffer, K H. Prueger, J L. Hatfield Jan 2011

Estimation Of Dariy Particulate Matter Emission Rates By Lidar And Inverse Modeling, C. C. Marchant, Kori D. Moore, Michael D. Wojcik, Randy S. Martin, R L. Pfeiffer, K H. Prueger, J L. Hatfield

Civil and Environmental Engineering Faculty Publications

Particulate matter (PM) emissions from agricultural operations are an important issue for air quality and human health and a topic of interest to government regulators. PM emission rates from a dairy in the San Joaquin Valley of California were investigated during June 2008. The facility had 1,885 total animals, including 950 milking cows housed in free-stall pens with an open-lot exercise area, and 935 dry cows, steers, bulls, and heifers housed in open lots. Point sensors, including filter-based aerodynamic mass samplers and optical particle counters (OPC), were deployed at select points around the facility to measure optical and aerodynamic particulate …


Two-Zone Transient Storage Modeling Using Temperature And Solute Data With Multiobjective Calibration: 1. Temperature, Bethany T. Neilson, S. C. Chapra, David King Stevens, Christina J. Bandaragoda Dec 2010

Two-Zone Transient Storage Modeling Using Temperature And Solute Data With Multiobjective Calibration: 1. Temperature, Bethany T. Neilson, S. C. Chapra, David King Stevens, Christina J. Bandaragoda

Civil and Environmental Engineering Faculty Publications

This paper presents the formulation and calibration of the temperature portion of a two-zone temperature and solute (TZTS) model which separates transient storage into surface (STS) and subsurface transient storage (HTS) zones. The inclusion of temperature required the TZTS model formulation to differ somewhat from past transient storage models in order to accommodate terms associated with heat transfer. These include surface heat fluxes in the main channel (MC) and STS, heat and mass exchange between the STS and MC, heat and mass exchange between the HTS and MC, and heat exchange due to bed and deeper ground conduction. To estimate …


Two-Zone Transient Storage Modeling Using Temperature And Solute Data With Multi-Objective Calibration: 2. Temperature And Solute, Bethany T. Neilson, David King Stevens, S. C. Chapra, Christina J. Bandaragoda Dec 2010

Two-Zone Transient Storage Modeling Using Temperature And Solute Data With Multi-Objective Calibration: 2. Temperature And Solute, Bethany T. Neilson, David King Stevens, S. C. Chapra, Christina J. Bandaragoda

Civil and Environmental Engineering Faculty Publications

This paper presents the multiobjective calibration results for temperature and solutefrom a two‐zone temperature and solute (TZTS) model which separates transient storageinto surface (STS) and subsurface (HTS) transient storage components. This modelcontains terms associated with surface heat fluxes in the main channel (MC) and STS, heatand mass exchange between the STS and MC, heat and mass exchange between the HTSand MC, and heat exchange due to bed and deeper ground conduction. To estimate theadditional parameters associated with a multiple‐zone model, a data collection effort wasconducted to provide temperature time series and solute tracer curves representingthe movement of heat and/or solute …


Groundwater Stress And Vulnerability In Rural Coastal Aquifers Of The Kalpitiya Peninsula, Sri Lanka, D. Jayasekera, Jagath J. Kaluarachchi, K. Villholth Jun 2010

Groundwater Stress And Vulnerability In Rural Coastal Aquifers Of The Kalpitiya Peninsula, Sri Lanka, D. Jayasekera, Jagath J. Kaluarachchi, K. Villholth

Civil and Environmental Engineering Faculty Publications

Rural coastal aquifers are undergoing rapid changes due to increasing population, high water demand with expanding agricultural and domestic uses, and seawater intrusion due to unmanaged water pumping. The combined impact of these activities is the deterioration of groundwater quality, public health concerns, and unsustainable water demands. The Kalpitiya peninsula located northwest of Sri Lanka is one area undergoing such changes. This land area is limited and surrounded almost completely by sea and lagoon. This study consists of groundwater sampling and analysis, and vulnerability assessment using the DRASTIC method. The results reveal that the peninsula is experiencing multiple threats due …


Climate Change Impacts On Water Resources Of The Upper Blue Nile River Basin, Ethiopia, U. Kim, Jagath J. Kaluarachchi, V. U. Smakhtin Dec 2009

Climate Change Impacts On Water Resources Of The Upper Blue Nile River Basin, Ethiopia, U. Kim, Jagath J. Kaluarachchi, V. U. Smakhtin

Civil and Environmental Engineering Faculty Publications

Climate change affects water resources availability of international river basins that are vulnerable to runoff variability of upstream countries especially with increasing water demands. The upper Blue Nile River Basin is a good example because its downstream countries, Sudan and Egypt, depend solely on Nile waters for their economic development. In this study, the impacts of climate change on both hydrology and water resources operations were analyzed using the outcomes of six different general circulation models (GCMs) for the 2050s. The outcomes of these six GCMs were weighted to provide average future changes. Hydrologic sensitivity, flow statistics, a drought index, …


Assessment Of Climate Change Impacts On Water Resources Of The Upper Blue Nile River Basin, Ethiopia, U. Kim, Jagath J. Kaluarachchi Sep 2009

Assessment Of Climate Change Impacts On Water Resources Of The Upper Blue Nile River Basin, Ethiopia, U. Kim, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Climate change affects water resources availability of international river basins that are vulnerable to runoff variability of upstream countries especially with increasing water demands. The upper Blue Nile River Basin is a good example because its downstream countries, Sudan and Egypt, depend solely on Nile waters for their economic development. In this study, the impacts of climate change on both hydrology and water resources operations were analyzed using the outcomes of six different general circulation models (GCMs) for the 2050s. The outcomes of these six GCMs were weighted to provide average future changes. Hydrologic sensitivity, flow statistics, a drought index, …


Data Collection Methodology For Dynamic Temperature Model Testing And Corroboration, Bethany T. Neilson, David King Stevens, S. C. Chapra, Christina J. Bandaragoda Jul 2009

Data Collection Methodology For Dynamic Temperature Model Testing And Corroboration, Bethany T. Neilson, David King Stevens, S. C. Chapra, Christina J. Bandaragoda

Civil and Environmental Engineering Faculty Publications

This article describes a data collection approach for determining the significance of individual heat fluxes within streamswith an emphasis on testing (i.e. identification of possible missing heat fluxes), development, calibration and corroborationof a dynamic temperature model. The basis for developing this approach was a preliminary temperature modelling effort onthe Virgin River in southwestern Utah during a low-flow period that suggested important components of the energy balancemight be missing in the o riginal standard surface-flux temperat ure model. Possible missing heat fluxes were identi fied as bedconduction, hyporheic exchange, dead zone warming and exchange and poor representation of the amount of …


Impact Of Vegetable Oil On Distribution Of Trichloroethylene In Groundwater During Enhanced Bioremediation, M. Pu, Ryan Dupont, William J. Doucette Oct 2008

Impact Of Vegetable Oil On Distribution Of Trichloroethylene In Groundwater During Enhanced Bioremediation, M. Pu, Ryan Dupont, William J. Doucette

Civil and Environmental Engineering Faculty Publications

Vegetable oils are increasingly being used as long-term carbon donors to stimulate reductive dechlorination of trichloroethylene (TCE). Besides potential enhancement of biodegradation, the addition of vegetables oils may impact TCE fate and distribution within the aquifer by acting as non-aqueous phase liquids (NAPL). Distribution coefficients for TCE between groundwater and four vegetable oils were determined using a slow-stir technique. Log vegetable oil/water distribution coefficients (log Kvw) were found to range from 1.0 to 2.56. TCE/vegetable oil distribution coefficients statistically increased with an increase in oil weathering while the concentration of dissolved organic carbon (DOC) in the water did not change …


Generation Of Monthly Precipitation Under Limited Data And Climate Change: An Example From The Upper Blue Nile River Basin, U. Kim, Jagath J. Kaluarachchi, V. Smakhtin Jul 2008

Generation Of Monthly Precipitation Under Limited Data And Climate Change: An Example From The Upper Blue Nile River Basin, U. Kim, Jagath J. Kaluarachchi, V. Smakhtin

Civil and Environmental Engineering Faculty Publications

This work develops a methodology to project the future precipitation in large river basins under limited data and climate change while preserving the historical temporal and spatial characteristics. The computationally simple and reliable conditional generation method (CGM) is presented and applied to generate reliable monthly precipitation data in the upper Blue Nile River Basin of Ethiopia where rain-fed agriculture is prevalent. The results showed that the temporal analysis with the CGM performs better to reproduce the historical long-term characteristics than other methods, and the spatial analysis with the CGM reproduced the historical spatial structure accurately. A 100-year time series analysis …