• Stock-Water Harvesting with Wax on the Arizona Strip

      Cooley, Keith R.; Brazell, Loren N.; Frasier, Gary W.; Fink, Dwayne H.; U. S. Water Conservation Laboratory, Phoenix, Arizona 85040; Bureau of Land Management, St. George, Utah (Arizona-Nevada Academy of Science, 1976-05-01)
    • Laboratory Weathering of Water-Repellent Wax-Treated Soil

      Fink, Dwayne H.; U. S. Water Conservation Laboratory, Phoenix, Arizona 85040 (Arizona-Nevada Academy of Science, 1976-05-01)
    • Academic Training for Groundwater Quality Specialists

      Schmidt, Kenneth D. (Arizona-Nevada Academy of Science, 1976-05-01)
    • Geomorphic Thresholds and Their Influence on Surface Runoff from Small Semiarid Watersheds

      Wallace, D. E.; Lane, L. J.; Southwest Watershed Research Center, Tucson, Arizona 85705 (Arizona-Nevada Academy of Science, 1976-05-01)
      The geomorphic threshold concept of landform evolution and its effect on hydrologic performance of drainage systems was investigated on small semiarid watersheds in Southeastern Arizona. Thresholds develop within a geomorphic system with time and can, when exceeded, cause drastic changes in the geomorphic features and in the hydrologic performance of the watershed. The slow continuous evolution of drainage characteristics can be suddenly altered with major readjustment of the landscape taking place. A new state of dynamic equilibrium will then prevail until the drainage system is again subjected to conditions which cause some geomorphic threshold to be exceeded. Areas of potential geomorphic readjustment can be identified from parameters such as channel slope, average land surface slope, drainage density, and mean length of first order streams and these data can be used as components in a calibrated kinematic-cascade model to determine the effects of various degrees of drainage system alteration. The influence on runoff from exceeding various geomorphic thresholds is tested and the resulting hydrologic modifications are simulated and discussed.
    • On the Modeling and Computational Aspects of Dynamic Programming with Applications in Reservoir Control

      Sniedovich, Moshe; Yakowitz, Sidney J.; Department of Systems and Industrial Engineering, University of Arizona, Tucson, AZ 85721 (Arizona-Nevada Academy of Science, 1976-05-01)
      A discrete stochastic multistage decision model is developed, in the framework of which the dynamic programming algorithm is defined. It is demonstrated that the algorithm may be used as a solution procedure for non-routine reservoir control problems. The study demonstrates that analytical considerations may be used to significantly reduce the amount of computation needed for the implementation of the algorithm. Two reservoir control problems are studied: The "reliability problem" in which one seeks a minimum-cost operation rule under a constraint which specifies the maximum probability of shortage allowed during the life-time of the project, and the "range problem" in which the objective is the minimization of the expected value of the range of fluctuation around a critical storage level.
    • Evaluation of Recharge Through Soils in a Mountain Region: A Case Study on the Empire and the Sonoita Basins

      Kafri, U.; Ben-Asher, J.; Water Resources Research Center, University of Arizona, Tucson 85721 (Arizona-Nevada Academy of Science, 1976-05-01)
      A conventional water balance method, employing long-term average values of rainfall, runoff and evapotranspiration yields near-zero recharge values for the Empire and the Sonoita basins. These results, however, are not in agreement with those obtained from an analysis of the local ground water regimes. A different approach for calculating recharge, based on the typical characteristics of these arid basins, is proposed. In particular, both basins are characterized by intense thunderstorms of short duration in the summer which occur usually towards the evening, and shallow, sandy-gravelly soils with a relatively high permeability overlying fractured rocks in the elevated mountain regions. These factors may cause a considerable amount of water to infiltrate through the soil profile, thereby escaping evapotranspiration during the following day. The proposed model deals with separate thunderstorm events using mean values of rainfall intensity and frequency corresponding to elevation. This model was coupled with a numerical solution of the flow equation which was used to solve the one dimensional water flow through a soil profile. The solution includes sink terms and was solved for the simultaneous processes of infiltration, moisture redistribution and evapotranspiration. The results obtained show almost no recharge in the low valleys, but significant recharge in the mountains. The amount of recharge increases with elevation and decreases with the depth of the soil profile.
    • Preliminary Results from a Study of Coal Mining Effects on Water Quality of the Tongue River, Wyoming

      Olsen, Richard D.; Dettmann, Edward H.; U. S. Energy Research and Development Administration; Division of Environmental Impact Studies, Argonne National Laboratory, Argonne, Illinois 60439 (Arizona-Nevada Academy of Science, 1976-05-01)
      A preliminary assessment survey, preparatory to a comprehensive ERDA sponsored watershed study, was conducted in the vicinity of Sheridan, Wyoming on the Tongue River and its major tributaries during the summer of 1975 to determine the extent and magnitude of aquatic environmental impacts induced by strip mining of coal at one major mine in the western Powder River Basin of Wyoming. Results of detailed physical and chemical analysis of mine discharge and ambient water quality of receiving streams were not conclusive, but suggest that water quality impacts of present mining activities in the area examinee' are small when compared to other apparent land use impacts observed upstream of the mine.
    • Application of a Double Triangle Unit Hydrograph to a Small Semiarid Watershed

      Diskin, M. H.; Lane, L. J.; Department of Hydrology and Water Resources, University of Arizona, Tucson; United States Department of Agriculture, Agricultural Research Service, Western Region, Southwest Watershed Research Center, Tucson, Arizona (Arizona-Nevada Academy of Science, 1976-05-01)
      Hydrographs of runoff from small watersheds in semiarid regions often have a sharp peak with a relatively short time of rise followed by a slower recession and a tail of low flow. This characteristic shape suggests the possible use of a double triangle unit hydrograph recently introduced to hydrology. The shape of this unit hydrograph is specified by four parameters, which may be estimated by an optimization procedure based on using the sum of absolute deviations or some other suitable criterion as an objective function. Rainfall and runoff data for a number of storm events on a small watershed in the Santa Rita Experimental Range in southeastern Arizona have been analyzed to test the above idea. Double triangle unit hydrographs were fitted to individual storm events. The differences in the shapes of individual unit hydrographs were found to be small so that they could be approximated by a single double triangle unit hydrograph.
    • Equilibrium Condition and Sediment Transport in an Ephemeral Mountain Stream

      Heede, Burchard H.; Rocky Mountain Forest and Range Experiment Station, Tempe, Arizona (Arizona-Nevada Academy of Science, 1976-05-01)
      Flow frequency curves supported the hypothesis that channel-forming flows are exceptional events in ephemeral mountain streams. This was substantiated by the lack of a relationship between sediment production and sediment yield. Numerous bed nickpoints indicated channel instability, despite gravel bars and log steps that are part of the slope adjustment processes. Due to differences in structural density between bars and steps, size distribution of the sediment deposits above them differs. Although only qualitative guidelines are presented, the watershed or wildlife manager should be in a position to utilize the formation of gravel bars and log steps for his management goals.
    • Resolutions of Analog Rainfall Records Relative to Chart Scales

      Chery, Donald L, Jr.; Beaver, Dave G.; USDA, Agriculture Research Service, Western Region, Southwest Watershed Research Center, Tucson, Arizona 85705; Soils, Water and Engineering Department, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1976-05-01)
      Five rainfall distributions, four l-in rainfall depths and one 3-in rainfall depth were plotted on charts with five different combinations of time and depth scales. The plotted events were read on an analog-to-digital converter by four different researchers. Each reading of a plotted record was compared with the known simulated rainfall-rate distribution. The correspondence of the rainfall rates read from the charts with the actual rainfall rate distribution is measured by an integral squared error and correlation coefficient. The results showed a general correspondence between error and the chart scale and a strong influence of maximum recorded rate and rate distribution on the error. For the chart scales evaluated, error did not become more directly associated with scale, except when recorded rates were less than about 10 in/hr. Error was directly related to the number of points read in any given trace by the relation E = 16.3N^(-0•426).
    • Chlorofluorocarbons as Hydrologic Tracers, A New Technology

      Randall, J. H.; Schultz, T. R.; Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona 85721 (Arizona-Nevada Academy of Science, 1976-05-01)
      The nationwide research undertaken to study environmentally dispersed chlorofluorocarbons introduced into the atmosphere from aerosol cans and refrigeration systems has indicated that these compounds are potentially ideal hydrologic tracers, especially Freon-11 (Cl₃CF). The major advantages of Cl₃CF as a tracer are its non-polluting conservative nature, extremely low toxicity and sorptivity on clays, quantifiable build-up in the atmosphere, and a detection limit of about 10⁻¹⁴ grams. Quick and inexpensive detection of Cl₃CF can be done using a field-operable gas chromatograph with a pulsed electron-capture detector system. The presence of Cl₃CF in ground water, indicating an age of less than 30 years, will permit delineation of recent recharge areas. The absolute age of the recharging water is proportional to the atmospheric concentration of Cl₃CF at the time of recharge. The simple quantifiable increase of Cl₃CF in the atmosphere should therefore yield more accurate ages than those determined by tritium analysis.
    • Determining Areal Precipitation in the Basin and Range Province of Southern Arizona - Sonoita Creek Basin

      Ben-Asher, J.; Randall, J.; Resnick, S.; Water Resources Research Center, University of Arizona, Tucson, Arizona 85721 (Arizona-Nevada Academy of Science, 1976-05-01)
      A linear relationship between point precipitation and elevation in conjunction with a computer four-point interpolation technique was used to simulate areal rainfall over Sonoita Creek Basin, Arizona. The simulation's sensitivity and accuracy were checked against the official isohyetal map of Arizona (Univ. of Arizona, 1965) by changing the density of the interpolation nodes. The simulation was found to be in good agreement with the official map. The average areal-rainfall was calculated by integration. Cumulative rainfall amounts were assumed to be stochastically independent from one season to another. The seasonal precipitations of forty years (1932-1972) were subdivided into five groups. to check for binomial distribution. The binomial model fits the historical data adequately. The binomial model for cumulative seasonal areal-precipitation provides one way to compute the return period. This information will be necessary for decision-makers and hydrologists to predict the area's future water balance.
    • A Multiobjective Approach to Managing a Southern Arizona Watershed

      Golcoechea, Ambrose; Duckstein, Lucien; Fogel, Martin M.; Department of System and Industrial Engineering, University of Arizona, Tucson, AZ 85721; Department of Hydrology and Water Resources, University of Arizona, Tucson 85721 (Arizona-Nevada Academy of Science, 1976-05-01)
      The case study of an Upper San Pedro River watershed is developed to show how a multiple objective approach to decision-making may be used in watershed management. The effects of various land treatments and management practices on water runoff, sediment, recreation,, wildlife levels, and commercial potential of a study area are investigated while observing constraints' on available land and capital. The example involves the optimization of five objective functions subject to eighteen constraints. In an iterative manner, the decision-maker proceeds from one noninferior solution to another, comparing sets of land management activities for reaching specified goals, and evaluating trade-offs between individual objective functions. This technique, which involves the formulation of a surrogate objective function and the use of the cutting plane method to solve the general nonlinear problem, hopefully provides a compromise between oversimplified and computationally intractable approaches to multiobjective watershed management.
    • Past Mining Activities and Water Quality in the Lynx Creek Watershed

      Felix, E. N.; Verma, T. R.; McCrary, E. E.; Thames, J. L.; Prescott National Forest, U.S.D.A., Forest Service; School of Renewable Resources, University of Arizona (Arizona-Nevada Academy of Science, 1976-05-01)
      Lynx Lake Watershed consists of approximately 13,600 acres of the Agua Fria drainage. About 13 percent of the area is patented mining claims (mainly copper} with numerous mining shafts, waste dumps, and mill tailings. Lynx Creek itself was once mined for gold and the creek bed still shows the scars of the dredging operations. Drainage from the numerous old mining sites show a certain extent of toxic mineral and sediment pollution of the water resources in the area. Lynx Creek carries runoff which is slightly acidic in nature and has a high concentration of copper, manganese, iron, zinc, and sulfates. The Sheldon Mine complex is considered one of the major sources of pollution to the lake. Aquatic life and recreation potential of the watershed is greatly reduced by the water pollution problem. The pollutants from the abandoned mine sites enter into Lynx Lake, a trout fisheries lake, which was created by damming the creek in 1962 by the Arizona Game and Fish Department. The Sheldon Tailings pond was rehabilitated during the summer of 1975 as part of a reclamation study and demonstration project that is currently in progress and being sponsored by SEAM (Surface Environment and Mining}. The study is being conducted cooperatively by the School of Renewable Resources, University of Arizona, and the Prescott National Forest. An excellent vegetative cover is established on the site and studies are being conducted to measure the beneficial effects of the reclamation on water quality.
    • Systematic Assessment of Uncertainties in an Environmental Impact Statement

      Nnaji, Soronadi; Davis, Donald R.; Duckstein, Lucien; Department of Hydrology & Water Resources and Systems and Industrial Engineering (Arizona-Nevada Academy of Science, 1976-05-01)
      An environmental impact statement (EIS) is meant to be a predictor of the consequences of actions on the environment. However, uncertainties in the statements make it difficult to determine the reliability of the predictions and thus the consequences of the actions. Hence, use of an EIS could be counter-productive if the inherent uncertainties are not recognized and considered in its evaluation. Examination of several EIS's from a systems viewpoint is used to expose the following sources of uncertainty: (1) the identification of the components of the system, (2) the natural uncertainty of the inputs to the system and of the transformation functions producing the output, (3) uncertainties in the modeling of the system due to limitations of sample, economic and technological data. The above viewpoint is used to analyze the Colorado River Salinity Control Project EIS. Uncertainties are identified and classified and means for assessing and incorporating their effect on the environmental impact assessment are discussed.
    • Study of the Adequacy of the Water Supply for the Carefree-Cave Creek Area

      Nemecek, Edward A.; Briggs, Philip C.; Arizona Water Commission (Arizona-Nevada Academy of Science, 1976-05-01)
    • Reservoir Design under Random Sediment Yield

      Duckstein, L.; Szidarovsky, F.; Yakowitz, S.; Departments of Systems and Industrial Engineering and Hydrology & Water Resources, University of Arizona, Tucson, AZ 85721; Department of Numerical Methods, Eötvös University, Muzeum körut, Budapest VIII, Hungary; Department of Systems and Industrial Engineering, University of Arizona, Tucson, AZ 85721 (Arizona-Nevada Academy of Science, 1976-05-01)
    • Lysimeter Snowmelt in Arizona Ponderosa Pine Forests

      Jones, Mikeal E.; Ffolliott, Peter F.; Thorud, David B.; School of Renewable Natural Resources, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
    • An Energy Budget Analysis of Evapotranspiration from Saltcedar

      Gay, L. W.; Sammis, T. W.; Ben-Asher, J.; School of Renewable Natural Resources, University of Arizona, Tucson; Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona; Water Resources Research Center, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
      Energy budget evaluations of evapotranspiration from saltcedar were carried out on the flood plain of the Rio Grande River, near Bernardo, New Mexico. The site was adjacent to the Bureau of Reclamation's lysimeter study of water use by saltcedar. The energy budget for the cloudless day of June 14, 1975, revealed that energy gains from net radiation totaled 432 cal/cm² , while energy losses (in cal/cm2 ), were 14 to stored energy, 31 to convection, and 387 to evapotranspiration (ET). The energy loss to ET is equivalent to the latent energy contained in about 6.5 mm of water. The energy budget values are reasonable for a phreatophyte community in a semi-arid environment. The latent energy loss compares favorably with 401 cal/cm² measured by three lysimeters, although there were discrepancies in timing and amounts of loss among the individual lysimeters. The mean canopy diffusion resistance was 1.90 sec/cm over a 10-hour daytime period on June 14. The mean resistance was combined with vapor pressure deficit to predict lysimeter ET on three subsequent days. The agreement was within 12 percent, which suggests that diffusion resistance may be useful for simple ET predictions.
    • Mathematical Modelling of a Forward Osmosis Extractor

      Moody, C. D.; Kessler, J. O.; School of Renewable Natural Resources, University of Arizona, Tucson; Department of Physics, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
      Osmosis occurs when two solutions of differing osmolar concentrations are separated by a membrane permeable to the solvent but not (or nearly not) to the solutes. This paper derives the relationship between the kinetics and design parameters of systems designed for the purpose of applying this process to problems such as agricultural water reclamation, dehydration of solutions and the production of potable nutrient solutions from sea water. Three mathematical models that include increasingly complex fundamental process assumptions are presented. In all cases the fundamental mechanical device is assumed to be a continuous flow extractor that incorporates a semipermeable membrane.