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DisciplineGraduate College (194)

Hydrology and Water Resources (194)

AuthorsNeuman, Shlomo P. (28)Ince, Simon (26)Evans, Daniel D. (25)Sorooshian, Soroosh (25)Simpson, Eugene S. (23)Davis, Donald R. (20)Harshbarger, John W. (19)Warrick, Arthur W. (17)Davis, Stanley N. (14)Maddock, Thomas (14)View MoreTypes
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Analysis of factors controlling groundwater flow for prediction of rates of groundwater movement and changes in quality, Atlantic coastal plains.

Ganus, William Joseph,1936- (The University of Arizona., 1972)

The development of an open pit phosphate mine in 1965 near Aurora, North Carolina, required groundwater withdrawals in excess of 50 million gallons per day for pressure relief from the underlying confined Castle Hayne aquifer. The effects of pumping from this limestone aquifer were widespread, extending over an area of more than 2,000 square miles in the first year before the pressure cone reached a stabilized condition. Salt water encroachment by lateral movement from downdip in the aquifer and by downward leakage from the Pamlico Estuary and Sound was possible if prolonged pumping were permitted. A joint project between state and industry in 1970-71 focused on analyzing the effects of five years of pumping for the purpose of making projections of future conditions of groundwater quality for continued and expanded groundwater development. The present study describes the method of flow net analysis used in the joint project to determine quantitatively the values of aquitard vertical permeability and aquifer transmissivity. These values provided the rational basis for making projections of groundwater movement and quality changes associated with this movement, A hydrologic projection model, developed in the present study, integrates the quality and volumetric flow of vertical leakage with that of lateral flow. Projection analyses are presented for two hypothetical cases of chloride distribution changed by continued pumping and for chloride changes associated with three different pumping regimes in the subject area.

A mathematical model of primary productivity and limnological patterns in Lake Mead

Everett, Lorne G. (The University of Arizona., 1972)

The temporal and spatial changes in chemical and biological properties of Lake Mead have been investigated, thereby indicating the sources of water pollution and the time of highest pollution potential. Planktonic organisms have been shown to indicate the presence of water problems. Macro- and micro-nutrient analyses have shown that primary productivity is not inhibited by limiting concentrations. A mathematical model has been developed, tested with one set of independent data, and shown worthy of management utility. Although the model works very well for the Lake Mead area, the physical reality of the MLR equation should be tested on independent data.

Calibration and validation of aquifer model.

Sagar, Budhi,1943- (The University of Arizona., 1973)

The main aim of this study is to develop a suitable method for the calibration and validation of mathematical models of large and complex aquifer systems. Since the calibration procedure depends on the nature of the model to be calibrated and since many kinds of models are used for groundwater, the question of model choice is broached first. Various aquifer models are critically reviewed and a table to compare them as to their capabilities and limitations is set up. The need for a general calibration method for models in which the flow is represented by partial differential equations is identified from this table. The calibration problem is formulated in the general mathematical framework as the inverse problem. Five types of inverse problems that exist in modeling aquifers by partial differential equations are identified. These are, to determine (1) parameters, (2) initial conditions, (3) boundary conditions, (4) inputs, and (5) a mixture of the above. Various methods to solve these inverse problems are reviewed, including those from fields other than hydrology. A new direct method to solve the inverse problem (DIMSIP) is then developed. Basically, this method consists of transforming the partial differential equations of flow to algebraic equations by substituting in them the values of the various derivatives of the dependent variable (which may be hydraulic pressure, chemical concentration or temperature). The parameters are then obtained by formulating the problem in a nonlinear optimization framework. The method of sequential unconstrained minimization is used. Spline functions are used to evaluate the derivatives of the dependent variable. Splines are functions defined by piecewise polynomial arcs in such a way that derivatives up to and including the order one less than the degree of polynomials used are continuous everywhere. The natural cubic splines used in this study have the additional property of minimum curvature which is analogous to minimum energy surface. These and the derivative preserving properties of splines make them an excellent tool for approximating the dependent variable surfaces in groundwater flow problems. Applications of the method to both a test situation as well as to real-world data are given. It is shown that the method evaluates the parameters, boundary conditions and inputs; that is, solves inverse problem type V. General conditions of heterogeneity and anisotropy can be evaluated. However, the method is not applicable to steady flows and has the limitation that flow models in which the parameters are functions of the dependent variable cannot be calibrated. In addition, at least one of the parameters has to be preassigned a value. A discussion of uncertainties in calibration procedures is given. The related problems of model validation and sampling of aquifers are also discussed.

Effect of urban street pattern on drainage.

Kao, Samuel Erh-chiang,1944- (The University of Arizona., 1973)

In cities, storm runoff is usually collected in the streets and conveyed to underground storm drains through inlets located at street level. Construction and maintenance of storm drain systems is always expensive. In semiarid regions with a very low frequency of storm occurrence, most cities use streets as the drainage route even though their primary function is for the movement of traffic. As a result, the shape of a runoff hydrograph at the outlet of an urban watershed will vary with the pattern of street arrangement within the watershed. The objective of this study is to investigate tradeoffs between alternative street patterns with respect to urban drainage. The study area is confined to residential subdivisions where the subdivision boundary is assumed to be the watershed boundary. Three street patterns, namely, rectangular, curvilinear and dendritic, are considered in this study. The cost-effectiveness technique is employed to give an objective evaluation for these three alternative patterns. The effectiveness is measured by three kinds of evaluators. The first evaluator is the flow depth at certain points on the streets; the second evaluator is the total time during which the streets are occupied by a certain depth of water; the third evaluator is the total cost associated with the construction of a street pattern. A framework of a distributed system model has been constructed for simulating the runoff hydrographs and flow depths at certain points on the streets. A parcel of land near Willcox, Arizona, is selected to illustrate how the model could be used. Possible subdivisions of the land for each of the three different types of street patterns are shown, and the runoff hydrographs and flow depths from each of the patterns are examined. It is found that the peak flow rate resulting from the rectangular pattern is 13 percent higher than that from the curvilinear pattern and 29 percent higher than that from the dendritic pattern. The dendritic pattern has the smallest percentage of street intersections occupied by water during a storm. Time of occupation of high water stages at street intersections is much shorter in the dendritic pattern than that in the rectangular and curvilinear patterns. The development cost for the dendritic pattern is the lowest among these three patterns. Therefore, the dendritic pattern appears to be the best type of street arrangement in terms of urban drainage.

Analysis of a multipurpose water resource system in southeastern Mexico.

Kunkel, J. R. (The University of Arizona., 1974)

Justification for the construction of water resource projects in developing countries has been traditionally based on benefit-cost analysis. This dissertation focuses on the standardized cost-effectiveness analysis for the planning, design and operation of water resource projects in developing countries and in particular southeastern Mexico. The "best" system is determined in terms of goals which reflect the physical, economic and social conditions of the region. The planning process starts by identifying goals which the water resource system or systems are desired to meet. These goals are then mapped into specifications in which the project needs are represented. Next, criteria or measures of effectiveness relating specifications to system capabilities are defined. These criteria are quantitative and qualitative. District alternative systems to meet the goals are defined and then their capabilities in terms of the measures of effectiveness are determined. The alternatives are then compared using both quantitative and qualitative measures of effectiveness. Then, using either a fixed-cost or fixed-effectiveness approach, the alternative system which most nearly satisfies the desired goals is selected. This study uses a real water resource system from which real decisions will be made. The methodology suggests improved ways of defining goals and criteria in developing countries and sets forth a concise framework upon which developing countries may base future water resource planning, design and operation.

Effect of vegetation characteristics on near soil moisture retrieval using microwave remote sensing technique

Lee, Khil-Ha (The University of Arizona., 2002)

Passive microwave remote sensing has shown potential for monitoring near surface soil moisture. This dissertation presents a new approach to representing the effect of vegetation on microwave emission by extending an existing model (Wilheit, 1978) of the coherent propagation of electromagnetic radiation through a stratified medium. The resulting multi-layer microwave emission model is plausibly realistic in that it captures the behavior of the vegetation canopy by considering the dielectric permittivity of the mixture of air and vegetation matter in the canopy and recognizing the vertical distribution of dielectric permittivity through the canopy. The model parameters required to specify the dielectric profile within the canopy are not usually available from data taken in typical field experiments, particularly the parameters that quantify the way the dielectric permittivity of the vegetation and air mix together to give the dielectric permittivity of the canopy. Thus, the feasibility of specifying these parameters using an advanced single-criterion, multiple-parameter optimization technique was investigated. The resulting model was also applied to investigate the sensitivity of microwave emission to specific vegetation parameters. The study continued with an investigation of how the presence and nature of vegetation cover influences the values of geophysical variables retrieved from multi-angle microwave radiometer spectrometer observations, using the upcoming Soil Moisture Ocean Salinity (SMOS) mission as a case study. The extended version of the Wilheit (1978) model was used to calculate synthetic observations of microwave brightness temperature at the look-angles proposed for the SMOS mission for three different soil moisture states (wet, medium, and dry) and four different vegetation covers (grass, crop, shrub, and forest). It was shown that retrieved values are only accurate when the effective values of the opacity coefficient used in the Fresnel model are made to vary in a prescribed way with look-angle, soil moisture status, and vegetation. The errors in retrieved values that may be induced by poor specification of vegetation cover were investigated by imposing random errors in the values of vegetation-related parameters in the forward calculations of synthetic observations made with the extended Wilheit model. The results show that poorly specified vegetation can result in both random and systematic errors in the retrieved values of the geophysical variables. (Abstract shortened by UMI.)

Groundwater in the Navajo sandstone : a subset of "Simulation of the effects of coal-fired power developments in the Four Corners region"

Dove, Floyd Harvey. (The University of Arizona., 1973)

Energy developments in the Southwest have established a basis for the examination of complexities involved in environmental decision making. The coalfired generation facilities exhibit an impact potential on the social, physical, and economic surroundings of both local and distant communities. A recent seventeen-volume report directed by the U.S. Department of Interior, The Southwest Energy Study, is an indicator of the magnitude of the situation. The Four Corners Program is a team research project with emphasis placed upon technology transfer. Simulation models are used to estimate the physical, economic, and social effects of a range of decisions concerning alternate power schedules. The research results are communicated to interest groups in other than the usual report form. A workshop environment allows the participants to interact with the decisions, the models, the results, and one another. One of the simulation models is the groundwater model. The groundwater model is used to estimate head declines in the confined and unconfined portions of the Navajo Sandstone and the Mesaverde Formation on Black Mesa. The Mesaverde Formation is found to be isolated from the Navajo Sandstone by the Mancos Shale and other intervening layers. A simulation routine developed by the Illinois State Water Survey is modified and adapted to the problem. As a result of the small amount of published aquifer data, minimum or below minimum values of aquifer properties and a sensitivity analysis were incorporated into model considerations. Pumping rates and pumping durations of groundwater for slurry transfer of coal define the decision space. The mining pumpage will have a negligible effect upon the Indian wells located in recharge areas of the Navajo Sandstone. The effects of mining pumpage upon potentiometric surfaces in the artesian portion of the Navajo Sandstone will range from zero to twenty percent of the artesian head, depending upon location and aquifer properties. Theoretical effects of groundwater pumpage on four monitor locations are quantified in terms of ranges of variation. These results can help to evaluate development plans for decision makers and other interest groups. With the future acquisition of measured drawdowns, consideration of theoretical and actual results can provide additional precision to aquifer parameter estimates. The Four Corners Program has a two year duration. The goal of the first year effort was the completion of simulation modeling. Beyond technical or prejudicial hurdles, the workshop encounters will require a public relations and communications posture which is conducive to group participation. The effectiveness of simulation as a means of technology transfer to a variety of users is yet to be evaluated.

Cognitive strawman : public input to a water resource planning system

Judge, Robert Michael,1941- (The University of Arizona., 1975)

The purpose of this research is to develop an information system to input public values into the planning and evaluation process. A hierarchy of goals is developed and disaggregated until terms meaningful to the general public, and describing the state of the world, can be input to the disaggregation. The relationship between the planning process and the public values expressed by the terms describing the state of the world is discussed. A function is hypothesized to quantify one measure of perceived well-being. The application of the quantifying function to the general public and to sub-groups of the general public is discussed. The conventional scaling techniques of ranking and rating are discussed and compared with a general allocation technique and other psychologic scaling methods to estimate the parameters of the quantifying function. A power function is tested against the satisfaction ratings given a group of samples of water of varying clarity. The parameters thus estimated are significantly greater than zero. The general allocation technique was used to recover the parameters of the quantifying function and compared to the parameters estimated by the regression analysis. The general allocation technique showed promise as a means of recovering the public values. The general allocation technique was then applied to determine the goal and sub-goal preferences of subjects in Arizona and the Rio Grande Valley of New Mexico. The research indicates that community values can be input to the planning process by use of the disaggregated goal structure and the quantifying function. The general allocation technique, used in a mail survey, shows promise as a means of recovering community preferences. The disaggregation of community goals may provide a means of linking the technical criteria of the professional and the values and goals of the general public. The development of a hierarchy of goals may provide an additional tool for decision makers and professionals in their analysis of public values.

Computerized water distribution management for the Upper Pampanga River Project, Philippines

Aldovino, Lino Pineda,1945- (The University of Arizona., 1977)

This study is concerned with the development of a model for realtime water distribution management for rice crop production in the Upper Pampanga River Project (Philippines). The model utilizes a management technique which considers water distribution at the farm level on a system-wide basis under the constraints of the present users and the physical system situations. The intent of the project is to rely as much as possible on the available uncontrolled streamflows and rainfall during the wet season in order to minimize releases from the Pantabangan reservoir, and thus conserve most of the impounded water for irrigation during the dry season. A computerized model which incorporates a parameter prediction-correction technique is developed for calculating the daily water scheduling for the entire canal network of the UPRP. To determine how much water is needed, a daily water budget at each of the 2,216 rotation areas is performed in conjunction with the daily predicted uncontrolled streamflows, rainfall, varying water requirement, and water status at the farm level. Subsequent delivery correction schedules are determined based on the degree of the prediction error. Studies were conducted for the determination of the appropriate rainfall prediction scheme used in the scheduling model. Selection of the scheme was done through simulation of field operations at the farm level and by the application of the rainfall-use efficiency criterion. Time lags along the Pampanga River and the canal network were analyzed to determine the possibility of supplying the entire network from the Pantabangan Dam within 24 hours. The idealized solution of the problem of inequitable distribution of water within a rotation unit is also presented. The ability of the model to provide situation-and-user-oriented guidelines for water distribution activities is demonstrated.

Parallel finite element algorithm for transient flow in bounded randomly heterogeneous domains

Ye, Ming (The University of Arizona., 2002)

We consider the effect of randomness of hydraulic conductivities K(x) on numerical predictions, without resorting to either Monte Carlo simulation, of transient flow in bounded domains driven by random source, initial and boundary terms. Our aim is to allow optimum unbiased prediction of hydraulic heads h(x, t) and fluxes q(x,t) by means of their respective ensemble moments, c and < q(x,t)>c, conditioned on measurements of K(x). These predictors have been shown by Tartakovsky and Neuman (1998) to satisfy exactly a space-time nonlocal (integro-differential) conditional mean flow equation in which < q(x,t)>c is generally non-Darcian. Exact nonlocal equations have been obtained for second conditional moments of head and flux that serve as measures of predictive uncertainty. The authors developed recursive closure approximations for the first and second conditional moment equations through expansion in powers of a small parameter σᵧ , which represents the standard estimation error of ln K(x). The authors explored the possibility of localizing the exact moment equations in real, Laplace- and/or infinite Fourier-transformed domains. In this paper we show how to solve recursive closure approximations of nonlocal first and second conditional moment equations numerically, to first order in σ²ᵧ, in a bounded two-dimensional domain. Our solution is based on Laplace transformation of the moment equations, parallel finite element solution in the complex Laplace domain, and numerical inversion of the solution from the Laplace to the real time domain. We present a detailed comparison between numerical solutions of nonlocal and localized moment equations, and Monte Carlo simulations, under superimposed mean-uniform and convergent flow regimes in two dimensions. The results are shown to compare very well for variances σ²ᵧ as large as 4. The degree to which parallelization enhances computational efficiency is explored.

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