bluuebunny/crossref_metadata_2025 huggingface dataset:
A Solution for Vertical Infiltration into a Dry Porous Medium
Authors: Brutsaert Wilfried
Published: February 2008

An exact solution is derived for the second term of J. R. Philip's [1957] series expansion originally developed for his numerical method of solution of the diffusion equation with diffusivity concentration dependent. The exact solution is made possible by the adoption of simple algebraic functions to describe the water content‐capillary suction and the water content‐capillary conductivity relationships of the porous medium and of a solution for horizontal infiltration presented in an earlier paper [Brutsaert, 1968]. Because of the fast convergence of the series, all terms of order higher than the second are negligible. Thus the present solution for the second term used in combination with the first term, representing the solution for horizontal infiltration, provides an adequate solution for vertical infiltration. Good agreement is obtained with published experimental data.
Application of the Digital Computer for Aquifer Evaluation
Authors: Pinder George F. , Bredehoeft J. D.
Published: February 2008

The unsteady‐state flow of a fluid in a confined aquifer can be approximated by linear, parabolic, partial‐differential equations. A digital‐computer program was written to solve these equations based upon an implicit finite‐difference technique. Calculated values compared favorably with analytical solutions for homogeneous, isotropic aquifers of simple geometry. An analysis of an aquifer at Musquodoboit Harbour, Nova Scotia, was made using this technique. Aquifer parameters in the digital model were modified until the results computed fitted the pump‐test data. The results indicate that this aquifer would come to equilibrium in about 100 days and would easily provide an adequate supply of water for the village of Musquodoboit Harbour. As a check of the digital model for this problem an electric analog of this aquifer was also constructed; the two solutions obtained compared favorably.
Computer Methods for Transient Analysis of Water‐Table Aquifers
Authors: Taylor George S. , Luthin James N.
Published: February 2008

The drawdown in a pumped unconfined aquifer can be analyzed by computer methods. The computer can give simultaneous solutions for flow in the saturated and unsaturated zone. The surface of seepage can also be included in the analysis.
Controlling transpiration in aspen with phenylmercuric acetate
Authors: Hart G. E. , Schultz J. D. , Coltharp G. B.
Published: February 2008

A 0.001 M spray of phenylmercuric acetate was applied by helicopter to part of an aspen stand in northern Utah in June, 1967. The natural fluttering action of the aspen leaves facilitated delivery of the spray to the stomate‐bearing underside of the leaves. Nine days after treatment, stomate width on treated trees averaged 2.4 μ as compared with 4.0 μ measured on untreated trees. Heat pulse measurements indicated reduction in daylight sap velocity from 11 cm/hr to 6 cm/hr. Seasonal soil moisture depletion was not significantly affected, although the pattern of water usage was delayed for about 6 weeks on the treated area.
Thermal stratification in lakes: Analytical and laboratory studies
Authors: Dake Jonas M. K. , Harleman Donald R. F.
Published: February 2008

Theories are developed for the time dependent vertical temperature distribution in a deep lake during the yearly cycle of solar heating and cooling. A portion of the incoming solar radiation is assumed to be absorbed at the water surface, whereas the remainder is absorbed exponentially beneath the surface. Heat is also conducted downward by molecular diffusion. A heat flux balance at the water surface, which accounts for back radiation and evaporative heat loss, is formulated as a boundary condition. The linear, second‐order heat transfer equation is solved by superposition of solutions for the surface absorbed radiation and the internally absorbed radiation. Analytical solutions are given for three different assumptions regarding the time dependence of the incoming radiation and the surface heat losses. At certain times, the resulting temperature and density distribution in the epilimnion are unstable. Under these conditions convective mixing and turbulent diffusion are accounted for by generating a surface mixed layer of uniform temperature. The depth of the surface mixed layer is determined by a thermal energy balance. The theory shows good agreement with field observations of temperature distributions in Lake Tahoe. Experiments are performed using artificial insolation (mercury vapor and infrared lamps) on a laboratory tank. We conclude that it is possible to simulate the development of thermal stratification under laboratory conditions.
A stochastic model of longitudinal diffusion in porous media
Authors: Todorovic P.
Published: February 2008

A set of tagged particles carried along by a fluid flow through a porous media is subject to random dispersion. The total distance from the origin, in the direction of the main flow traveled by a tagged particle, is a stochastic process. To apply Lagrangian description of the dispersion the distribution function of the traveled distance for every time t is determined. This distribution is not Gaussian and depends on two parameters which in turn depend on hydraulic conditions. To apply Eulerian description, the distribution function of time a tagged particle to travel a given distance x is derived. This distribution is not Gaussian either, and depends on the same two parameters. The sum of these two distributions is always one. This identity represents the relationship between Lagrangian and Eulerian descriptions. According to experimental results, the theoretical distributions agree reasonably well with observed distributions.
Some effects of surface cover geometry on infiltration rate
Authors: Koon J. L. , Hendrick J. G. , Hermanson R. E.
Published: February 2008

Infiltration into the soil is regulated in part by sealing of the soil surface by raindrop impact. Soil surfaces protected from such impact maintained higher rates of infiltration than exposed soil surfaces. It was hypothesized that the cover particles protected the covered portion of the soil and prevented the reaction of raindrop impact on the soil state. The soil under the cover particles remained in the original state in which infiltration could occur. However, since the cover particles in this study were impervious, infiltration could not occur on the covered area but would occur along the available perimeter of the cover particles. Water would then move in both vertical and lateral directions. The effective lateral distance that the water moved after entry was defined as the effective width. To evaluate the effects of soil surface cover on the infiltration rate of soils exposed to raindrop impact, simulated rainfall was applied at a constant rate to one soil type in small plots with free drainage, and square and rectangular cover particles of varying sizes and percentages were used as surface cover.
Riverbed Degradation Prediction
Authors: Hales Zelton L. , Shindala Adnan , Denson Keith H.
Published: February 2008

A mathematical‐graphical procedure for predicting the longitudinal extent of degradation with time downstream from large capacity reservoirs is presented. For such a prediction it is necessary to have an indication of the outflow release rates of the structure, original distribution curves of the bed materials, and channel cross sections. The evaluation of bed slope and the energy slope appears to be a critical factor in the computations. Miscalculation of these two variables could seriously affect the solution; therefore extreme care is urged in their determinations.
A Statistical Comparison of Meander Planforms in the Wabash Basin
Authors: Chang T. P. , Toebes G. H.
Published: February 2008

The planforms of two natural meandering rivers, the Wabash River and the White River in Indiana, were investigated using a variety of statistical techniques. Local curvature series were used as the basic statistical descriptor of the planform.Two groups of factors, (1) geology and soil and (2) flow rate and channel slope, were found to be major factors that control the meander planform. This conclusion was supported by probability distribution as well as by time series analysis studies. A method of moving spectrums was developed for the analysis of nonstationary data that are typical in geomorphology. This method was applied to the curvature series of the White and Wabash rivers. It appears to provide an objective way to describe local statistics of the meander shape.
Analysis of Lag Phase BOD Curves Using the Monod Equations
Authors: Braun Heinz B. , Berthouex Paul M.
Published: February 2008

The Monod biokinetic relations have been used to develop a 3‐parameter model to describe the biochemical oxidation of waste water substrates as observed in biochemical oxygen demand (BOD) tests, including those tests with an initial lag phase. A criterion relating the biological parameters of the model to the occurence of a lag phase is presented. The model was applied to several sets of data that reflect a variety of conditions. Some statistical problems involving parameter correlation were noted.
Least Squares Estimation of Constants in a Linear Recession Model
Authors: James L. Douglas , Thompson William O.
Published: February 2008

Least squares can be used for estimating constants in a linear recession model from published average daily streamflows. A model with two recession constants was derived and successfully tested on a number of Kentucky streams. It can be used to estimate recession constants from daily streamflows stored on magnetic tape or punched cards without resorting to time‐consuming graphical techniques. Equations and procedures are provided for recessions represented by either one or two recession constants using both a weighted and unweighted estimation procedure. In applying the two techniques, empirical evidence indicates the simpler unweighted procedure is preferable.
Desalting Saline Ground Water for Irrigation: A Case Study, Buckeye Area, Arizona
Authors: Parkinson Harold L. , Maletic John T. , Wagner Joseph P. , Sachs Milton S.
Published: February 2008

A study was made of an irrigated area in Arizona to evaluate costs and benefits associated with desalting saline ground water from seven wells as an improved water source for irrigation. Both multistage flash distillation (MSF) and electrodialysis (ED) processes were evaluated. The study area involved 1376 acres near Buckeye, Arizona. Well water quality varied from 1580 to 4600 ppm. Irrigation water qualities of 400, 900, and 1500 ppm are developed by the two processes. Adaptable cropping patterns are selected for maximum returns. A total of six alternative plans are compared. Direct, indirect, and public benefits for the projected year of 1990 are generated by shifts to higher value crops, intensive double cropping, increased crop yields, reduced water use, reduced fertilizer costs, reduced irrigation labor, and from increased flow of farm products. Costs are based on such features as the desalting facilities, well water collection system, product storage reservoir, conveyance and distribution system, brine disposal system, blending facilities (MSF only), gypsum addition system (ED only), and water treatment facilities. Benefit‐cost ratios increased with improved water quality. Investment costs per acre were found to be high. The most favorable benefit‐cost ratio involved use of the ED process at a water quality level of 400 ppm.
Reducing Land Subsidence in the Wilmington Oil Field by Use of Saline Waters
Authors: Pierce Robert L.
Published: February 2008

The subsidence at Long Beach encompassed an area of 22 square miles sinkage ranging from 2 feet to 30 feet. The subsidence is attributed to pressure reduction due to oil production from the Wilmington oil field. The injection of saline water has successfully stopped the Long Beach harbor area subsidence. In addition, 15 years experience in injecting saline water into the Wilmington oil field has developed a technology that has successfully made an economic waterflood project. The overall economics have been improved through progress in water quality control to prevent corrosion and scaling and to maintain injectivity. The water quality control learned over the years is now being used to prepare the oil field produced brines for injection. Historically the produced brines have been disposed of into the harbor waters. However, the possibility of pollution of coastal waters exists, not only from contamination due to oil, chemicals, and fines, but also to an oxygen deficiency in the water that would be harmful to fish life. Through December 1968, 2.1 billion barrels of saline water have been injected into the Wilmington oil field (2.5 billion through December 1969). The bulk of this was ocean water produced from source wells open to sands 100 feet to 400 feet deep. The current injection rate of the field is 1.1 million barrels per day. Expanded use of the oil field's produced brine for injection is taking place and 550,000 barrels per day of this brine will replace source well water during 1969. The methods being used to clean the oil field's produced brine include: (1) filtration, (2) re‐cycling through the shallow source water beds, and (3) blending with fresh or other saline waters.
Groundwater Storage Control Under Institutional Restrictions
Authors: Burt Oscar R.
Published: February 2008

Optimal allocation of groundwater over time is analyzed for situations in which institutional constraints prevent imposition of a criterion based strictly on economic efficiency. The various cases considered range from unrestricted optimization to a model in which the only decision variable is the time at which uncontrolled pumping is stopped and in which the basin uses periodic recharge from that point into perpetuity. The latter case has been analyzed before but under the assumption of constant marginal productivity of water used in the basin. This assumption is relaxed and its impact on equilibrium storage is examined.
Relationship between Horizontal Strain near a Well and Reverse Water Level Fluctuation
Authors: Wolff Roger G.
Published: February 2008

Measurements of radial surface strains near a pumping well showed compression near the well that changed to tension farther away from the well. A theoretical model is presented. In general, this model reproduces the measured strains. Observations of anomalous increase in pore pressure in a clay adjacent to the pumped aquifer are related to the development of these strains. These increases in pressure are attributed to distortion of the pore space in the clay resulting from the transference of horizontal strain from the aquifer via shear. Applying a conceptual model that permits the transference of strain across confining layers to unpumped artesian aquifers accounts for reverse water level fluctuations.
A Portable, Automatic Water Sampler
Authors: Doty Robert D.
Published: February 2008

A water sampler is described that is designed to operate where no outside source of power is available and where access to the point of sampling is difficult. The sampler is lightweight, battery powered, and automatically bottles 16 samples at preset time intervals between servicings.
Hysteresis During Infiltration and Redistribution in a Soil Column at Different Initial Water Contents
Authors: Vachaud Georges , Thony Jean‐Louis
Published: February 2008

Experimental results dealing with flow processes involving hysteresis effects in the suction‐water content relationship were obtained on a vertical column of soil submitted to the following successive controlled flow conditions: (1) redistribution of water following a constant head infiltration in an initially air‐dried column. (2) constant head infiltration followed by redistribution, and (3) constant flux infiltration followed by controlled evaporation and redistribution.

Water contents were measured by using gamma ray attenuation, and water suctions were obtained simultaneously from 10 pressure transducers distributed along the soil column, each one being connected to a tensiometer. A data acquisition system permitted fully automated measuring sequences. All the data were punched on tape and treated with a computer.

Examination of the changes of water content and water suction at a given depth permitted us to obtain precise information on the hysteretic behavior of Ψ (θ). This analysis showed that the scanning curves for a single reversal can be defined uniquely with reference to the transition water content θ*, that the independent domain theory appears to be inadequate for describing soil water hysteresis completely, and that k(θ) can be considered practically unique.
Potential Energy and Stream Morphology
Authors: Yang Chih Ted
Published: February 2008

Use of the analogy of entropy in thermodynamics reveals two basic laws which govern the formation of all stream systems. The first law is the law of average stream fall, which states that under the dynamic equilibrium condition the ratio of average fall between any two different order streams in the same river basin is unity. The second law is the law of least rate of energy expenditure, which states that during the evolution toward its equilibrium condition a natural stream chooses its course of flow in such a manner that the rate of potential energy expenditure per unit mass of water along this course is a minimum. This minimum value depends on the external constraints applied to the stream. The concavity of a river basin is shown to be the determinative factor in the formation of a stream system. On the basis of Horton's law and the law of average stream fall, longitudinal stream profiles can be calculated. The agreement between observed data and the theories found in this study is excellent.
Use of Linear Programing for Estimating Geohydrologic Parameters of Groundwater Basins
Authors: Kleinecke David
Published: February 2008

Simulation models of groundwater basins require that values be given for geohydrologic parameters such as permeability and storage capacity. In present practice these parameters are initially estimated and later adjusted by trial and error to improve the ability of the model to simulate some known portion of the water history. It has been suggested that this process might be reversed to deduce geohydrology directly from the historical record. This suggestion was tested against a basin studied earlier by the California State Department of Water Resources. The fitting criteria used gave rise to linear programing formulations, which were solved from the basin data. The approach shows promise in that about one‐third of the basin parameters were evaluted, but further development is required. It is believed that historical records, although apparently overdetermining the system of equations, actually underdetermine the system because of redundancy effects. The approach appears to offer the best known method for estimating the effective aquifer depth.
Dissolved Solids‐Discharge Relationships: 2. Applications to Field Data
Authors: Hall Francis R.
Published: February 2008

Six mixing models and a number of equations derived from them have been proposed for some possible dissolved solids‐discharge relationships in streams. The equations can be put in a form suitable for statistical analysis by digital computer. In actual application, however, a major problem arises in determining which equation or model is most applicable because the data tend to fit two or more equations equally well. A particular difficulty is encountered in deciding whether a constant component of dissolved solids is present. This decision is most critical when only total dissolved solids or electrical conductivity is used for concentration. An examination of other chemical data, if available, along with knowledge of the stream help decide which model is most suitable. Other problems may arise from factors such as nonrandom trends and variations in the storage volume‐discharge relationship. Under these circumstances, an extension of the equations beyond the range of actual data or inferences about physical or chemical significance of the equations or constant terms should be made with caution.
Overland Flow on an Infiltrating Surface
Authors: Smith Roger E. , Woolhiser David A.
Published: February 2008

The partial differential equation for vertical, one‐phase, unsaturated moisture flow in soils is employed as a mathematical model for infiltration rate. Solution of this equation for the rainfall‐ponding upper boundary condition is proposed as a sensitive means to describe infiltration rate as a dependent upper boundary condition. A nonlinear Crank‐Nicholson implicit finite difference scheme is used to develop a solution to this equation that predicts infiltration under realistic upper boundary and soil matrix conditions. The kinematic wave approximation to the equations of unsteady overland flow on cascaded planes is solved by a second order explicit difference scheme. The difference equations of infiltration and overland flow are then combined into a model for a simple watershed that employs computational logic so that boundary conditions match at the soil surface. The mathematical model is tested by comparison with data from a 40‐foot laboratory soil flume fitted with a rainfall simulator and with data from the USDA Agricultural Research Service experimental watershed at Hastings, Nebraska. Good agreement is obtained between measured and predicted hydrographs, although there are some differences in recession lengths. The results indicate that a theoretically based model can be used to describe simple watershed response when appropriate physical parameters can be obtained.
Optimal Identification of Aquifer Diffusivity Using Quasilinearization
Authors: Yeh William W‐G. , Tauxe George W.
Published: February 2008

An analytical procedure is presented to solve the problem of identifying aquifer diffusivity in an unconfined aquifer and stream interaction system. The fluctuation of the aquifer head in response to a flood wave is used as observations. The governing nonlinear partial differential equation is replaced by a system of nonlinear ordinary differential equations for which the technique of quasilinearization is applied. The procedure is straightforward and converges quadratically. It requires neither graphical matching nor trial and error manipulations. Numerical experiments are presented and compared with published experimental data.
Measurement of Vertical Groundwater Velocity from Temperature Profiles in Wells
Authors: Sorey Michael L.
Published: February 2008

Vertically moving groundwater transports heat by convection and causes curvature in the earth's thermal profile. Dimensionless plots of the temperature distribution in wells can be matched with published type curves to obtain solutions for vertical groundwater velocity, if the thermal conductivity of the solid‐fluid complex is known or can be estimated. Rates of upward movement through semiconfining beds determined from temperature studies in the San Luis valley of Colorado and the Roswell basin of New Mexico were in good agreement with rates computed from pumping tests and water budget methods. Limitations of the method result from instability in borehole fluids, measurement detail required, and magnitudes of flow that can be detected.
Development and Distribution of Permeability in Carbonate Aquifers
Authors: Legrand H. E. , Stringfield V. T.
Published: February 2008

Unlike aquifers in nonsoluble rocks in which the permeability tends to be both inherent and fairly even in local distribution, aquifers in carbonate rocks tend to have their permeability developed through circulation of water and solution of the rock and to have an uneven distribution of permeability. The extent to which near‐surface carbonate rocks have permeability developed in them depends on the degree to which water that is high in dissolved carbon dioxide has moved through joints and other openings to places of discharge.The following well‐established generalizations indicate that the geometry of carbonate aquifers is commonly different from that of other aquifers. (1) The circulation of water and solution activity tend to be greatest in the upper part of the zone of saturation and tend to lessen with increased depth. (2) The moderately large openings in the path of bulk flow of groundwater tend to enlarge by solution action; contrastingly, the small openings not in the path of bulk flow enlarge only slightly. The texture of permeability in a few carbonate aquifers is fine and even but in most carbonate aquifers is more commonly coarse and uneven. Where the texture of permeability is fine and fairly even, as in the Biscayne aquifer of southeastern Florida, the aquifer may be riddled with a close network of solution channels or interstitial openings. Where the texture of permeability is coarse and uneven, ramifying solution channels are bounded by a large volume of relatively dense impermeable carbonate rocks. The channel network system is especially prominent in the upper part of the zone of saturation. In many cases the gross permeability seemingly decreases exponentially with increasing depth. The dynamic water table, becoming flatter and moving lower as permeability increases, is bounded above by a cavernous unsaturated zone that is a relic of the former permeable zone of saturation. With passing geologic time, the solution channel network loses its aquifer characteristics when (1) the water table moves downward to the base of the aquifer, (2) the cavernous rocks are destroyed by erosion, or (3) the aquifer becomes buried under later deposits and lies below the groundwater circulation system. The history of some carbonate aquifers includes early development under water table conditions, burial and preservation under later deposits, resurrection, and reactivation in the modern groundwater circulation system. Observable or discernible recognition can be made of (1) aquifers having fine textured permeability, (2) aquifers having coarse textured permeability, and (3) aquifers that have been resurrected and are now reactivated; each type of aquifer has distinctive characteristics that help in hydrologic evaluations of carbonate rock systems.
Flood Routing in Channels with Bank Seepage
Authors: Zitta Victor L. , Wiggert James M.
Published: February 2008

Bank seepage occurs along natural streams bounded by an alluvial material when the passage of a flood wave produces a rise and fall in the stream stage. Owing to the difficulties of measuring flow rates in a porous medium, the quantity of bank seepage and its effect on the attenuation of a flood wave have not been determined from experimental observations. As an alternative for the purposes of this study, the equations of motion were used to describe flood flows in an idealized rectangular channel bounded by banks of a homogeneous, isotropic, porous medium in which the Boussinesq equation governs flow. The channel and the banks were assumed to be underlain by an impervious layer. Numerical simulation of a sinusoidal flood wave in the channel showed that bank seepage causes significant attenuation of the wave in narrow channels bounded by a relatively pervious material. This attenuation is characterized by a reduction in the hydrograph peak and sustenance of the flow during recession. In wide channels and in channels bounded by a relatively impervious material, no significant attenuation of the flood wave occurs.
Watershed Physics: Model of the Soil Moisture Characteristic
Authors: Rogowski A. S.
Published: February 2008

The procedure is proposed by which reasonable estimates of the soil moisture characteristic can be obtained when a reliable curve is not available. Moisture content and pressure at air entry and at 15 bars constitute the required input parameters. The parameters are easily determined and at times can be readily abstracted from literature or estimated from published data. Applicability of the model is tested on graded sand and eight soils.
Radial flow in an infinite aquifer undergoing conversion from artesian to water table conditions
Authors: Moench Allen F. , Prickett Thomas A.
Published: February 2008

A closed form mathematical solution is given for water level conversion from artesian to water table conditions due to a well discharging at a constant rate. The solution is obtained from the analogous case of heat flow in cylindrical symmetry in which freezing or melting takes place. A single nonleaky artesian aquifer that is homogeneous, isotropic, and infinite in areal extent is considered. The well fully penetrates the aquifer and is infinitesimal in diameter. Dimensionless curves are given, and suggestions are made to aid in the analysis and interpretation of the aquifer test data.
Effect of using averaged data on the computed evaporation
Authors: Jobson Harvey E.
Published: February 2008

Because it is seldom necessary to determine the total evaporation from a body of water for short periods of time, it is tempting to use meteorologic parameters that have been averaged over long intervals of time and the semiempirical mass transfer equation to determine the total evaporation. This paper illustrates the effect of time in averaging wind speeds and temperatures on the computed evaporation. Data collected during a 15‐month interval at Lake Hefner near Oklahoma City, Oklahoma, were analyzed. Each set of data represents the average meteorologic conditions during a 30‐minute time interval. From these data the effect of averaging for periods of 3 hours, 1 day, and 1 month was determined. The value of the coefficient in the semiempirical mass transfer formula is shown to be independent of the averaging time when this time is less than 1 day in length. The frequency distribution of the averaging error was determined for each averaging period. An averaging error larger than ±5% occurred about 3% of the time for 3‐hour averages and about 20% of the time for daily averages. It is concluded that averaging periods of 1 month should be avoided in situations similar to those at Lake Hefner.
Analytical flow nets in channel seepage flows
Authors: Bruch John C. , Fernandez Sainz Leandro B.
Published: February 2008

An analytical solution technique to determine streamlines and equipotential lines in steady two‐dimensional seepage from a single triangular channel into a permeable soil underlain at a finite depth by a drain was obtained by using conformal mappings. The technique was applied to triangular channels having side slopes of 45°. The results were compared with those from a published finite difference solution. The complex integrations were computed by using an interactive on line computer system. This computational method proved extremely easy to apply and a rapid means of obtaining accurate results.
Evapotranspiration from a Greasewood‐Cheatgrass community
Authors: Harr R. D. , Price K. R.
Published: February 2008

Groundwater elevation, soil moisture, and precipitation were monitored to evaluate the components of water loss from two greasewood‐cheatgrass (Sarcobatus vermiculatus‐Bromus tectorum) communities in south central Washington. Annual evapotranspiration was 21–25 cm, 18–31% of which was the transpiration of groundwater. The greatest loss from the system was the evapotranspiration of stored soil moisture, but this moisture was unavailable to greasewood. This study confirms that water use rates are a function of depth to water up to 2.3 meters, but indicates a more complicated mechanism at depths of up to 13 meters. Shrub height, canopy coverage, and total leaf surface area are inversely related to depth to water, and the rate of water use is in turn directly related to these plant‐associated features.
Accuracy of stream link lengths derived from maps
Authors: Werritty A.
Published: February 2008

The lengths of >100 exterior links for three catchments in Devon and Somerset in southwest England were obtained by field survey. These link lengths were compared with data obtained from the provisional edition of the 1:25,000 map series and the Old County map series at 1:2500. The degree of correspondence with the 1:25,000 series was very poor, but both regression and analysis of variance methods failed to reveal any major difference between the field data and the data based on the 1:2500 series. It is suggested that, other than complete field mapping, the 1:2500 series represents the most reliable data source available for the delineation of stream networks in the area.
Comparison of multiple regression and principal component regression for predicting water yields in Kentucky
Authors: Haan C. T. , Allen David M.
Published: February 2008

The advent of the digital computer has made the analysis of large quantities of hydrologic data possible. It has also made possible certain types of analyses that were not feasible for hand calculation. Among these techniques are multiple regression and regression on the principal components of data matrices. This report compares these two techniques when they are applied to the problem of predicting water yields in Kentucky.
Eureka! It fits a Pearson type: 3 distribution
Authors: Matalas N. C. , Wallis J. R.
Published: February 2008

Under the assumption that a random variable is distributed as Pearson type 3, a comparison was made between moment and maximum likelihood estimates of the parameter values of the distribution and the variate values at specified probability levels. For the region where maximum likelihood solutions may be obtained, maximum likelihood estimates yield solutions that are less biased and less variable than the comparable moment estimates. When these results are extended to quite small samples, say, N≈25, they become quite pronounced as the probability p becomes greater than N/(N+1).
Measure of three‐dimensional drainage basin form
Authors: Anderson Malcolm G.
Published: February 2008

When investigators have wanted surrogates for basin form in connection with river flow characteristics, they have frequently resorted to measuring aspects of the basin from a map, intuitively reasoning that they afford a suitable description of form. Since this reasoning is not necessarily so, a model is derived that generates the three‐dimensional form of a basin by using six coefficients derived from map analysis. The model reproduces correctly the important characteristics of surface roughness and spatial autocorrelation.
Unsteady flow to a partially penetrating, finite radius well in an unconfirmed aquifer
Authors: Kipp Kenneth L.
Published: February 2008

A more realistic theoretical solution to the problem of unsteady flow to a single, partially penetrating well of finite radius in an unconfined aquifer is developed. The aquifer is assumed to be homogeneous, isotropic, and infinite both in thickness and lateral extent. Perturbation expansion techniques are used to linearize the free surface boundary condition, so that the solution satisfies the boundary conditions through first order in the small parameter ϵ, provided that the drawdowns remain small, and that a time limit is imposed. The basic potential field is created by distributing dipole moments over the surface of the well bore and solving the resulting integral equation numerically. The solution can be used to model pumped well behavior for the initial period after the start of pumping. A more accurate model of pumped well behavior is possible with this solution, since it is not restricted to the constant flow rate or constant head modes of simulation. Results show that the assumption of constant discharge operation in earlier, more approximate solutions to this problem is more realistic than the assumption of constant head operation.
Mass balance and spectral analysis applied to Karst hydrologie networks
Authors: Brown M. C.
Published: February 2008

Underground karst drainage systems can be studied by the input‐output relations of rivers that flow through them. First, tracers enable the quantity of water at a sink that flows to a specific spring, and the fraction of a given spring derived from a sink, to be calculated. Second, when these methods are not applicable, cross‐covariance and cross‐spectral transfer function analysis can be used to examine input‐output stage records. These give information about the vadose and/or phreatic nature of the system. An inaccessible karst drainage system in western Alberta has a tracer flow‐through time of +80 to +130 hours and a positively skewed cross covariance of +70 to +124 hours; therefore the cave is not completely water filled. Additional unknown inputs are substantiated by a negatively peaking cross covariance.
Public investment impacts and regional economic growth
Authors: Lewis William Cris
Published: February 2008

The ideas and concepts articulated extend the theory underlying the role of public investment, including investment in water resource development, in the process of regional economic growth. Hypotheses concerning interdependences among public investment impacts are investigated in the context of an industrial location model of regional growth. The analysis suggests that construction impacts as well as developmental impacts should be considered in the investment decision‐making process. Implications for the growth center strategy for regional development are also discussed.
Galerkin solution of the inverse problem for aquifer transmissivity
Authors: Frind Emil O. , Pinder George F.
Published: February 2008

The inverse problem in aquifer analysis may be solved by a Galerkin finite element approach. The proposed solution is applied to an inhomogeneous isotropic aquifer for which steady state piezometric head is known and transmissivity is unknown. The condition for existence and uniqueness of a solution is that transmissivity must be known along a line crossed by all streamlines in the flow system. In the Galerkin solution this condition may be stated alternatively in terms of flux, so that knowing the discharge at a well may satisfy the uniqueness requirement. Isoparametric finite elements are used, polynomial shape functions approximating aquifer geometry, hydraulic head, and transmissivity. The flexibility of the isoparametric elements permits using an irregular grid with nodes directly at observation points. Applications show that the solution is highly sensitive to the degree of approximation in the functional representation of hydraulic head but relatively insensitive to the representation of transmissivity. The finite element solution converges to a unique solution as element size decreases.
Loss of particulate organic materials from semiarid watersheds as a result of extreme hydrologic events
Authors: Gifford Gerald F. , Busby Frank E.
Published: February 2008

Three debris basins in southern Utah were sampled to determine the amount of particulate organic debris deposited as a result of a single extreme runoff event on each of the three semiarid watersheds above the basins. The total quantity of large particulate organic materials lost from each contributing area ranged from 64.06 kg/ha to 12.89 kg/ha. Vegetation on the watersheds was primarily big sagebrush (Artemisia tridentata), pinyon (Pinus spp.), and Utah juniper (Juniperus osteosperma). Nutrient losses due to the removal of particulate organic materials from each watershed were also approximated.
Minimization of power expenditure in a riffle‐pool alluvial channel
Authors: Cherkauer Douglas S.
Published: February 2008

The hypothesis, initially proposed by Leopold and Langbein (1962), that rivers adjust their flow so as to minimize total power expenditure and to minimize the sums of the variances of power and of other dependent variables is tested with empirical data and a mathematical flow model for a short reach of the Treia River in central Italy. The minimizations are tested by mathematically generating a set of flows that could occur under existing conditions and comparing the pertinent values with those of the modeled real flow. For the limited set of conditions observed, i.e., steady base flow over a stable set of riffle‐pool bed forms with no movement of sediment, it is shown that the stream has adjusted in the postulated manner.
Just a moment!
Authors: Wallis J. R. , Matalas N. C. , Slack J. R.
Published: February 2008

The distribution functions for three statistics, the mean, standard deviation, and coefficient of skewness, for small samples from various distributions were obtained by Monte Carlo experiments. Sample sizes of 10 (10) 90 were considered, and the distributions used were the normal, Gumbel (extreme value type 1), log normal, Pearson type 3 (gamma), Weibull, and Pareto type 1 (Pearson type 4). Values of the coefficient of skewness used in generating the samples were in the range [0.0, 15.0]. Pronounced skews, biases, and constraints in the sampling properties of the statistics were observed. Examples of the available graphs of the distribution functions are presented.
Some generalized beta distributions of the second kind having desirable application features in hydrology and meteorology
Authors: Mielke Paul W. , Johnson Earl S.
Published: February 2008

Two distinct versions of the generalized beta distribution of the second kind are considered. These beta‐type distributions compare favorably with the commonly used gamma and log normal distributions in their ability to fit selected sets of accumulated streamflow and precipitation amount data. The comparisons are based on empirical results associated with three different goodness of fit criteria. Since the cumulative distribution functions of these beta‐type distributions are in closed form, they possess unique computational advantages over the gamma and log normal distributions.
Effect of partial penetration on flow in unconfined aquifers considering delayed gravity response
Authors: Neuman Shlomo P.
Published: February 2008

Previously, a new analytical model was proposed by the author for the delayed response process characterizing flow to a well in an unconfined aquifer. It was shown that contrary to prevailing belief this process can be simulated by using constant values of specific storage and specific yield without recourse to unsaturated flow theory. In the present work the theory is extended to account for the effect of a well partially penetrating a homogeneous anisotropic unconfined aquifer. Field and laboratory evidence is quoted to suggest that the elastic storage properties of unconfined aquifers may often be much more pronounced than those of deep‐seated confined aquifers composed of similar materials. The need for further research into the mechanical properties of unconfined aquifers and the role of unsaturated flow in the response process is emphasized.
Linear decision rule: A note on control volume being constant
Authors: Nayak Satish C. , Arora Sant R.
Published: February 2008

For the release management of reservoirs, a rule known as the linear decision rule has been proposed in the literature. According to this rule, a release of Xi made during the period i is a function of initial storage Si‐1 and a decision parameter bi for this period; i.e., Xi = Si‐1 ‐ bi. If the minimum required pool volume is assumed to be equal to Am · C, where Am is a fraction between zero and one and C is the optimal capacity of the reservoir, then the quantity C ‐ Am · C has been defined as control volume. This paper offers a proof that the control volume is independent of Am for given flow data.
On the transformation of point rainfall to areal rainfall
Authors: Rodriguez‐Iturbe Ignacio , Mejía José M.
Published: February 2008

A general methodology is developed for the transformation of point rainfall to areal rainfall. The reduction factor is shown to depend solely on the expected correlation coefficient between the point rainfall at two randomly chosen points in the area in consideration. The methodology can be used to characterize the input to rainfall‐runoff models, and it includes the case in which multiple inputs are used in the model in the form of a subdivision in modules of the whole catchment. An example is worked out discussing the different methodologies for the estimation of total mean volume of rainfall over an area.
Surface heat loss from cooling ponds
Authors: Ryan Patrick J. , Harleman Donald R. F. , Stolzenbach Keith D.
Published: February 2008

A technique is developed for accounting for the contribution of free convection to the evaporation from a cooling pond. Established formulas for forced (wind‐driven) evaporation are corrected for convective effects and used in a formula for surface energy balance to estimate heat fluxes and surface temperatures of cooling ponds. The resulting expression for total heat loss agrees with observed cooling pond performance better than other formulas presently in use. Surface heat loss coefficients may be derived from the new heat loss formula for use in calculating temperature rises induced by heated discharges.
Pricing irrigation water in Iran
Authors: Gardner B. Delworth , Madhi Youssef , Partovi Syamak , Morteza Hendizadeh , Mehdi Saghatoleslami
Published: February 2008

Iran has nationalized water and is faced with the problems of pricing it. A proposal for pricing irrigation water is presented in which water is managed by nonprofit water authorities. An irrigation project is divided into zones, and a single price is proposed for each zone. Operation and maintenance costs are set as a lower limit on price, and a certain fraction of ability to pay is set as an upper limit. Zones are ranked by assigned reimbursable costs, and a system is proposed that would produce water revenues in aggregate equal to total project reimbursable costs. For those zones where water is priced above reimbursable cost the price is set at that level where the price minus reimbursable costs, as a percentage of the difference between the upper limit and reimbursable cost, is the same for all zones. For those zones where the price is below reimbursable cost, the recommended price is at the upper limit.
Objective double‐mass analysis
Authors: Chang Mingteh , Lee Richard
Published: February 2008

Objectivity in double‐mass analysis is attained by using a completely computerized method of stepwise slope comparisons and variance analysis. The method is adaptable to hydrologic series with multiple inconsistencies. The results suggest important physical causes for inconsistencies in annual precipitation series in mountainous areas.
The use of streamflow models in planning
Authors: Jackson Barbara Bund
Published: February 2008

A large and growing number of models are available for generating synthetic streamflow traces for use in planning. A survey of these techniques suggests some general precepts for the construction and use of hydrologic models in planning.
Drainage of groundwater resting on a sloping bed with uniform rainfall
Authors: Towner G. D.
Published: February 2008

The differential equation derived by Childs for groundwater flow over a sloping bed, the streamlines being assumed to be parallel to the slope, is integrated for the case of ditches and uniform rainfall. Expressions are obtained for the maximum vertical water table height, the location of this maximum and of the watershed, and the water table shape. Calculated water table heights are in much better agreement with previously published experimental data than those calculated from an earlier theory based on the assumption that streamlines are horizontal. Thus Childs' revised assumption is confirmed. An approximate solution for the form of the water table under small rainfall rates is also derived.
Stochastic variation of water quality of the Passaic River
Authors: Mehta B. M. , Ahlert R. C. , Yu S. L.
Published: February 2008

The stochastic structures of some water quality time series were examined. These time series include daily observations in streamflow, water temperature, BOD, and dissolved oxygen deficit. Autoregressive integrated moving average (Arima) models were used to describe the random components of these time series. It was found that except for the BOD the Arima models could provide very satisfactory results.