Civil and Environmental Engineering Commons^™

A Spatially Distributed Energy Balance Snowmelt Model, David G. Tarboton, Tanveer G. Chowdhury, Thomas H. Jackson

Reports

This paper describes an energy balance snowmelt model developed for the prediction of rapid snowmelt rates responsible for soil erosion and water input to a distributed water balance model. The model uses a lumped representation of the snowpack with two state variables, namely, water equivalent and energy content relative to a reference state of water in the ice phase at 0 degrees Celcius. This energy content is used to determine snowpack average temperature of liquid fraction. This representation of the snowpack is used to determine snowpack average temperature of liquid fraction. This representation of the snowpack is used in a …

Measurements And Modeling Of Snow Energy Balance And Sublimation From Snow, David G. Tarboton

Reports

Snow melt runoff is an important factor in runoff generation for most Utah rivers and a large contributer to Utah's water supply and periodically flooding. The melting of snow is driven by fluxes of energy into the snow during warm periods. These consist of radiant energy from the sun and atmosphere, sensible and latent heat transfers due to turbulent energy exchanges at the snow surface and a relatively small ground flux from below. The turbulent energy exchanges are also responsible for sublimation from the snow surface, particularly in arid environments, and result in a loss of snow water equivalent available …

The Source Hydrology Of Severe Sustained Drought In Th Southwestern U.S., David G. Tarboton

Reports

This paper considers the risk of drought and develops drough scenarios for use in the study of severe sustained drought in the Southwestern United States. The focus is on the Colorado River gbasin and regions to which Colorado River water is exported, especially southern California, which depends on water from the Colorado River as well as the four major rivers in northern California. Drought scenarios are developed using estimates of unimpaired historic streamflow as well as reconstructions of streamflow based on tree ring widths. Drought scenarios in the Colorado River are defined on the basis of annual flow at Lees …

Introducing Uncertainty Of Aquifer Parameters Into An Optimization Model, Robert L. Ward, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A stochastic analysis is made for a previously described groundwater contaminant management model {Peralta and Ward, 1988). The stochastic model is based on incorporating uncertainty of the aquifer parameters transmissivity and effective porosity into the model. This is accomplished by finding the partial derivative of drawdown with respect to each of these parameters using a Taylor series expansion approximation of the Theis equation. Input that is required for the stochastic version is the mean of the transmissivity and effective porosity, the coefficient of variation of the transmissivity and effective porosity, and a reliability level (0%-100%) . The reliability is a …

Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, Ghassan R. Musharrafieh, Richard C. Peralta, Ronald J. Hanks, Lynn M. Dudley

Civil and Environmental Engineering Faculty Publications

Irrigation strategies which maximize crop yield while maintaining target salt concentration in the root zone and/or prevent salt from leaching to the groundwater are computed using a nonlinear, one dimensional, simulation/optimization management model. The included constraint equations maintain a water volume balance and salt transport in the unsaturated zone. Utilized are implicit finite difference forms of the nonlinear, unsteady, unsaturated water flow equation (Richards's equation), and the diffusion-convection solute transport equation. Other constraints include nonlinear functions describing the hydraulic properties of the medium (hydraulic conductivity as a function of matric potential, volumetric water content as a function of matric potential, …

Preventing Pesticide Contamination Of Groundwater While Maximizing Irrigated Crop Yield, Richard C. Peralta, M. A. Hegazy, G. Musharrafieh

Civil and Environmental Engineering Faculty Publications

A simulation/optimization model is developed for maximizing irrigated crop yield while avoiding unacceptable pesticide leaching. The optimization model is designed to help managers prevent non-point source contamination of shallow groundwater aquifers. It computes optimal irrigation amounts for given soil, crop, chemical, and weather data and irrigation frequencies. It directly computes the minimum irrigated crop yield reduction needed to prevent groundwater contamination. Constraint equations used in the model maintain a layered soil moisture volume balance; describe percolation, downward unsaturated zone solute transport and pesticide degradation; and limit the amount of pesticide reaching groundwater. Constraints are linear, piecewise linear, nonlinear, and exponential. …

Modeling Technique For Optimal Recovery Of Immiscible Light Hydrocarbons As Free Product From Contaminated Aquifer, Grant S. Cooper Jr., Richard C. Peralta, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Contamination sites associated with light non-aqueous phase liquids {LNAPL) are numerous and represent difficult cleanup problems. Remediation methods for cleanup of LNAPL fluids in subsurface systems are continuously evolving with the development of various technologies for pump.-and~treat, soil venting, and in-situ bioremediation. Evaluating the effectiveness of remediation techniques as well as attempting to improve their efficiency has been a focus of many researchers, These efforts have included the development of computer simulation models to predict and analyze the fluid movement, entrapment, and mobilization of three~phase systems in porous media. The capability of computer models that not only simulate but optimize …

S/O Modeling Technique For Optimal Containment Of Light Hydrocarbons In Contaminated Unconfined Aquifers, Grant S. Cooper Jr., Jagath J. Kaluarachchi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

An innovative approach is presented to minimize pumping for immobilizing a floating plume of a light non-aqueous phase liquid (LNAPL). The best pumping strategy is determined to contain the free oil product and provide for gradient control of the water table. This approach combined detailed simulation, statistical analysis, and optimization. This modeling technique uses regression equations that describe system response to variable pumping stimuli. The regression equations were developed from analysis of systematically performed simulations of multiphase flow in an areal region of an unconfined aquifer. Simulations were performed using ARMOS, a finite element model. ARMOS can be used simulate …

Review Of Planning Distribution Model (Pdm) Status And Application Possibilities For The Egyptian Irigation System, Robert W. Hill, Richard C. Peralta, Gary P. Merkley

Civil and Environmental Engineering Faculty Publications

The comprehensive water management Planning Distribution Model, or PDM, was developed by the Biological and Irrigation Engineering Department, Utah State University (USU), under contract with the United States Bureau of Reclamation (USBR). Most of the work was carried out in the Planning Sector, Ministry of Public Works and Water Resources (MPWWR) , in Cairo, under the Planning Studies and Models Component of the USAID funded Irrigation Management Systems Project.

Optimal Contaminant Plume Management With Us/Wells, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A micro-computer based software package developed at utah State University for computing optimal pumping strategies for well systems (US/WELLS) is demonstrated. US/WELLS is used to determine the optimal time-varying sequence of extraction and injection rates when only limited data is available. The software determines the extraction/injection rates, in pre-specified locations, needed for immobilizing and/or extracting a groundwater contaminant plume. In the optimization problem, the objective function can be either to minimize the extraction/injection rates needed {linear) or to minimize the hydraulic power used for lifting water (quadratic). In either case, different weights can be assigned to emphasize any time period. …

Optimizing Conjunctive Water Use In A Dynamic Stream Aquifer System, Getachew Belaineh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Long-term water management planning models frequently use large time steps and must employ fairly crude assumptions (such as average climatic conditions, etc.). Managing stream aquifer systems during a dry season requires using finer discretization in time and space. Presented is a computer model, US/REMAX, developed by Utah State University personnel for aiding best management of stream-aquifer systems for both long and short eras. The model computes strategies for optimally allocating surface and ground water resources in time and space. For a water supply problem the model can maximize the sum of delivered surface and ground water. For an environmental protection …

Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, G. R. Musharrafieh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We developed a simulation-optimization model which maximizes crop yield while maintaining target salt concentration in the root zone, and/ or preventing salt from leaching to the groundwater. The model performs nonlinear optimization and simulation. Implicit finite difference forms of the nonlinear, transient, unsaturated water flow equation, and the convection-diffusion equation are embedded as constraints. Other constraints include nonlinear functions describing the hydraulic properties of the medium. The objectives of the management model is to develop irrigation strategies which prevent salt leaching to the groundwater when salty irrigation water is used. Five different irrigation strategies are developed for Huntington Research Farm, …

Climatic Variability And Dynamics Of Great Salt Lake Hydrology, Taiye B. Sangoyomi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The time evolution of the Great Salt Lake hydro-climatic system is studied from the perspective of nonlinear dynamics. The dynamics are reconstructed in phase space using the Great Salt Lake volume time series. Important attributes for describing the system are then obtained from the reconstructed space. These include the minimum number of state variables required to describe the system inferred from a determination of the intrinsic dimension, and characterization of the system in terms of linear/nonlinear, and deterministic/stochastic. Other attributes obtained are the dominant modes of behavior of the system, as well as the limit of predictability or information loss, …

Practical Optimization Modeling For Contaminant Plume Management, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to greatly speed the process of computing desirable groundwater pumping strategies for plume management. They make the process of computing optimal strategies fairly straightforward and can help minimize the labor and cost of groundwater contaminant clean-up.

Probable Maximum Flood Estimation In Northern Utah, Khin Maung Win

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The probable maximum flood (PMF) is used for the xxi assessment of maximum flood potentials in spillway sizing of new dams and in evaluating the adequacy of existing hydrologic structures. Determination of the PMF begins with the estimation of the probable maximum precipitation (PMP) for a particular dam site. Selecting hydrologic methods and assumptions for converting PMP to PMF, which are most appropriate for Utah conditions, is important to meet current inflow design flood (IDF) safety standards.

The objectives of this study were (a) to demonstrate a maximization approach to PMF determination, (b) to evaluate effects of basin characteristics and …

Jet Velocity Dissipation And Modelling With Aeration, Stephen J. Schlenker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of natural aeration and fall height upon velocity dissipation and modelling were studied. Underwater velocities and void ratios (proportion of air volume to total volume) were measured along the jet centerline at various depths in the receiving pool under 1- and 2-inch diameter vertical circular free-falling jets. Maximum air bubble penetration depths were also measured. In the tests, the nozzle velocities were designed so that the two differently sized models would have equivalent Froude numbers for direct comparison of respective underwater parameters. Air entrainment-the natural development of air bubbles within a pool receiving a free-falling jet-causes voids to …

A Mechanistic Approach To Modeling Habitat Needs Of Drift-Feeding Salmonids, R. Craig Addley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mechanistic model is developed to determine the habitat needs of drift-feeding stream salmonids from the direct cause-and-effect relationships of environmental and physiological variables on net energy intake (NEI). The model determines NEI by subtracting energy costs (basal metabolism, swimming cost, digestion cost) and losses (egestion and excretion) from the gross energy intake obtained as a result of simulated prey capture. The prey capture portion of the model utilizes components of the predation model of C.S. Holling and the prey capture model of N.F. Hughes and L.M. Dill to determine the rate of prey capture (gross energy intake) as a …

Simulation Of Daily Precipitation From A Nonparametric Renewal Model, Balaji Rajagopalan, Upmanu Lall, David G. Tarboton

Reports

Wet/dry spell characteristics of daily precipitation are of interest for a number of hydrologic applications (e.g., flood forecasting or assessment of erosion potential). Here, we examine issues related to designing an appropriate nonparametric scheme that focuses on spell characteristics for resampling historically daily precipitation data. A subset of the nonparametric wet/dry spell model presented in Lall et al (1993) is tested with synthetic data to justify the strategy proposed for applications. An application of the nonparametric wet/dry spell model to a Utah data set follows. Performance is judged on a set of statistical measures. Numerical comparisons of model performance with …

A Kernel Quantile Function Estimator For Flood Frequency Analysis, Young-Ii Moon, Upmanu Lall

Reports

A kernel estimator (KQ) of the quantile function is presented here. Boundary kernels are used for extrapolation of tail quantiles. The bandwidth of the estimator is chosen using an automatic, "plus-in" method. Confidence intervals for the estimated quantile are estimated by bootstrapping. Comparisons of the estimator with selected tail probability estimators are offered. The KQ estimator presented here is shown to be competitive with other estimators.

Effectiveness Determination Of Two Different Water-Saving Devices For Toilet Tanks, C. Earl Israelsen, Gilberto Urroz

Reports

Introduction: The project was successful in obtaining eight different brands of new toilet tanks in the 3.5 gals-per-flish-bariety, and two used ones requiring 5.0 gals per flish. The tanks were installed on a t atime on a padded stell frame and connected to a water supply. The float was adjusted to maintain the water in the tank at the level recommended by the manufacturer. When the flush and shut-off mechanisms were adjusted properly, the testing begain.

A Prototype Computer Based Tutorial For The Use Of Highway Patrol Radar Guns, William J. Grenney, Thad E. Senti

Reports

Executive Summary: The software contained in this package, termed POSAT (Police Officer Standards and Training) is the prototype knowledge-base decision support system developed specifically for the Utah State Police Academy. All police officers must be certified annual for the use of radar guns. This self-study computer program is intended to reduce the cost of providing field training for hundreds of police officers each year. By installing the POSAT software at remote locations, polic officers within a certain districut need only to travel to the nearest remote testing sight to take the exam and renew their radar certification. POSAT automatically transmits …

Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa

Reports

Executive Summary: Many pathways exist for transportation agencies and other public and private agencies to become responsible for sites contaminated by hazardous wastes. As a reult, agencies frequently face a multitude of lega, regulatory, financial, technical, and health risk problems. When transportation agencies become involved in the remediation of hazardous waste sites, the common practice is to hire consultants and contractors for the clean up process. Because the field of hazardous waste site remediation is changing so rapidly, agency personnel evaluating the consultant's recommendations need to ahve access to the most recent regulatory and remediation information. Early stages of the …

Development Of Mountain Climate Generator And Snowpack Model For Erosion Predictions In The Western United States Using Wepp: Phase Iv, David S. Bowles, U. Lall, D. G. Tarboton, E. Malek, B. Rajagopalan, T. Chowdhury, E. Kluzak

Reports

Executive Summary: Introduction: This report summarizes work conducted during the funding period (December 1, 1991 through September 30, 1992) of a Research Joint Venture Agreement between the Intermountain Research Station, Forest Service, U. S. Department of Agriculture and the Utah Water Research Laboratory (UWRL), Utah State University (USU). The purpose of the agreement is to develop a Western Mountain Cilmate Generator (MCLIGEN) similar in function to the existing (non-orographic area) Climate Generator (CLIGEN), which is part of the Water Erosion Prediciton Project (WEPP) procedure. Aso, we are developing a Western U.S. Snowpack Simulation Model for includsion in WEPP. In the …

Interpretation Of Drill Log Data: Dlog3d - A Probabilistic Tool For Analyzing Subsurface Soil Variability, Alaa El-Din Ali, Upmanu Lall

Reports

Groundwater contamination potential is directly related to the location of zones of high hydraulic conductivity. Sedimentary depositional environments can be quite complex. Pockets of sand of varying thickness and orientation may be scattered over the aquifer. A contaminant pathway can esist where these pockets or lenses are interconnected. Aquifer pump tests do not provide useful information on the occurrence of such lenses. Drill log data directly sample the soil, but may represent very local sections of the aquifer, and are of relatively poor quality. Here we present a methodology (DLOG3D) that allows a probabilistic interpretation of drill log data that …

Candi (Chemical And Irrigation Management) Users Manual, Vs 2.0., A. H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This manual describes an interactive computer model, CANOl. CANOl is a decision support tool designed to aid in on-farm pesticides and irrigation management. CANOl simulates downward chemical movement through the soil in response to different irrigation practices. CANOl estimates the relative amount of a non-polar organic chemical which remains in the soil profile by the time it reaches a specified depth. Future releases of CANOl will involve the management of different types of chemicals. CANOl is also able to delineate the wellhead protection areas for domestic wells. For this purpose, CANOl involves USEPA's model (MWCAP). Different versions of CANOl handle …

Best Management Of Pesticide And Irrigation Application Systems: Background And Candi Software, Alaa H. Aly, Richard C. Peralta, Howard M. Deer

Civil and Environmental Engineering Faculty Publications

In this chapter, we discuss a commonly-used volume balance approach for simulating the movement of water through the root zone. We then show how this approach can be coupled with pesticide leaching prediction. Finally we show how information about irrigation system design can be used with the previous processes. The result is an integrated approach for estimating the environmental consequences of irrigation and pesticide management.

Ground-Water Policy-Making Support: Usem Optimization Modelling Plus Gis And Graphics, Richard C. Peralta, Christopher M. U. Neale, Ali Gharbi, Mazibur Khan, Oscar Daza, Douglas Ramsey, Kurt Vest

Civil and Environmental Engineering Faculty Publications

A support tool for ground-water management decision making involves integration of a multiobjective optimization model, GIS and graphics software. Two results are improved consideration of spatial data within the optimization model and improved conversion of optimal strategies to real-world application. Another result is improved visualization of the trade-offs involved between conflicting management goals.

Us/Wells Vs. 1.05 User's Manual, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Presented is a computer program, US/WELLS, that is designed to solve several types of groundwater management problems. The acronym US/WELLS stands for Utah State WELL System. This decision-support tool is usable by persons slightly familiar with groundwater hydraulics. It can be valuable for practical management of groundwater systems that satisfy certain criteria.

Sprinkler Irrigation-Pesticide Best Management Systems, A. Y. Ranjha, Richard C. Peralta, Robert W. Hill, A. M. Requena, Howard M. Deer, M. Ehteshami

Civil and Environmental Engineering Faculty Publications

The relative reduction in potential groundwater contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices, and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate irrigation application depths. The movement of pesticides through soils following sprinkler irrigations was simulated with a one-dimensional model. Pesticide contamination of groundwater can be reduced by careful selection of pesticides, using properly designed irrigation systems, and improved water management techniques. Procedures for selecting an appropriate sprinkler system design and pesticide are presented. KEYWORDS. Pesticides, Leaching, Sprinkler irrigation, Irrigation depth, Irrigation system design, Soil, …

Evaluation Of Mechanisms Of Alteration And Humification Of Pahs For Water Quality Management, Ronald C. Sims, Carolyn K. Abbott

Reports

Introduction: Creosote-pentachlorophenol (PCP) is a mixture commonly used as a wood preservative in the U.S. (1). A 1988 survey (2) indicated that 1,397 wood preserving waste contaminated sites exist in the United States consisting of 555 active wood treatment plants and 842 inactive plants. Stinson (3) indentifed 58 wood preserving sites on the National Priorities List, of which 51 have PCP and/or creosote or polycyclic aromatic hydrocarbon (PAH) contamination. Principal classes of organic constituents present in creosote waste are PAHs (~85% by weight) and phenolics. PAHs with less than three fused benzene rings comprise 69% (i.e., naphthalene, anthracene and phenanthrene); …