• Antritranspirants as a Possible Alternative to the Eradication of Saltcedar Thickets

      Cunningham, Robert S.; Brooks, Kenneth N.; Thorud, David B.; School of Renewable Natural Resources, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1975-04-12)
      The response of saltcedar (Tamarix pentandra Pall.) to several antitranspirants was evaluated in laboratory, greenhouse and small -scale field studies using potted plants. Anti - transpirants may provide a treatment alternative to the eradication of saltcedar thickets for water salvage objectives. Transpiration rates were reduced by 23 to 44 percent for 7 to 20 days in the greenhouse, and by 18 to 32 percent for 2 to 8 days in the field. No serious damage to the plants was apparent. One of the most effective antitranspirants considered for a hypothetical saltcedar thicket and a hypothetical operational treatment program, based on estimated cost data, would result in reallocated water costing approximately 55 dollars per acre foot for a single treatment. About 19 acres of saltcedar thicket would have to be treated to provide one acre -foot of reallocated water in this case.
    • Parameter Influence on Runoff Modeling

      Kao, Samual E.; Roefs, Theodore G.; Ince, Simon; Ferguson, Morris & Associates, Inc., Scottsdale; Department of Hydrology & Water Resources, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1975-04-12)
      The influence of some model parameters on runoff simulation was investigated. The model parameters considered included space and time increments, rainfall input, and channel roughness. The parameters' effect on runoff appeared to be very small, but channel roughness greatly influenced flow depth.
    • Application of Direct Osmosis: Possibilities for Reclaiming Wellton-Mohawk Drainage Water

      Moody, C. D.; Kessler, J. O.; School of Renewable Resources, University of Arizona, Tucson; Department of Physics, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1975-04-12)
      A direct osmosis plant can reclaim twenty to thirty thousand acre feet of Wellton-Mohawk brackish drainage water using no more nitrogen fertilizer than is normally used in the Yuma, Coachella valley, Imperial Valley and the bordering Mexican areas. On a per-acre basis ammonium sulfate-driven direct osmosis can reclaim about one percent of the total irrigation requirement from 3000 ppm brackish water. In addition to the ammonium sulfate-driven direct osmosis efficiency, the by-product energy recovery of the manufacture of the fertilizer and the low technology inherent in direct osmosis processes make direct osmosis an appealing water reclaiming process.
    • State Water Planning

      Steiner, Wesley E.; Arizona Water Commission, Phoenix, Arizona (Arizona-Nevada Academy of Science, 1975-04-12)
      From the establishment of the Arizona resources board in 1928 until the Arizona Water Commission was formed in 1971, no state water plan was developed. Since 1971, the longest and most intensive planning studies have been concerned with allocation of Colorado River water through the central Arizona project. Future plans involve desalting sea water, weather modification, importation of water, etc. The Arizona state water plan ultimately will be a plan of management of Arizona's limited water resources. Water plans and economic and environmental impact evaluations are scheduled for completion by july, 1977.
    • Watershed Indicators of Landform Development

      Heede, Burchard H.; Arizona State University, Tempe, Arizona; Colorado State University, Fort Collins (Arizona-Nevada Academy of Science, 1975-04-12)
      Traditionally, watershed management is concerned with water and sediment yield, vegetation, soils, and meteorology, but not with geomorphology. Often it is in this field that the explanation can be found for the formation and present condition of a watershed and its future development. Examples are presented to demonstrate that factors in the hydraulic geometry of streams indicate whether a watershed is in an active stage of landform development, or is in dynamic equilibrium. Some general guides for the practitioner are provided. Watershed management research cannot afford to ignore the basic geomorphic setting of watersheds. If geomorphology is not considered, the researcher's results could be misinterpreted.
    • The Geomorphic and Hydraulic Response of Rivers

      Simons, D. B.; College of Engineering, Colorado State University, Fort Collins, Colorado 80523 (Arizona-Nevada Academy of Science, 1975-04-12)
      The importance of water resources and an increasing interest on improvement of out environment have identified the urgent need for methods to predict river response due to various changes resulting from proposed water resource planning. Fluvial geomorphology and hydraulic elements that are related to the interpretation and modeling of response to the problem are presented. Interpretation of alluvial rivers should be preceded by a qualitative analysis and information is presented which should be adequate to carry this out in most cases. This should be followed by a quantitative evaluation of channel response and water sediment routing using theory supplemented by physical and mathematical model studies of the system.
    • The Arizona Water Resources Information System - 1975

      Winikka, Carl C.; Arizona Resources Information System, Department of Revenue, Phoenix, Arizona (Arizona-Nevada Academy of Science, 1975-04-12)
      The Arizona resources information system is designed to serve on going needs of the people of Arizona through state, federal and local agencies. The various land and water environmental organizations use the resource system for their research. The aris has prepared Arizona orthopotoquads, developed early land use classification systems, and evaluated electronic data processing graphical and analytical systems and many information systems.
    • Applications of Direct Osmosis: Design Characteristics for Hydration and Dehydration

      Kessler, J. O; Moody, C. D.; School of Renewable Resources, University of Arizona, Tucson; Department of Physics, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1975-04-12)
      In direct (normal, forward) osmosis water automatically flows through a semipermeable membrane from a "source" solution of low concentration to a "driving" solution with higher solute content. The process requires a membrane which is impermeable to the solutes; hydrostatic pressure differences are not directly involved and can be set equal to zero. In principle, direct osmosis is a low -technology, low-power consumption method for reducing the water volume of industrial effluents or liquid agricultural products, and for reclaiming brackish irrigation water. In the latter application the driving solution may utilize fertilizer as a solute; the source solution is drainage that contains harmful salt components. This type of operation has been experimentally demonstrated. This paper summarizes basic physical principles and introduces some quantitative design factors which must be understood on both a fundamental and on an applications level.
    • Water Resources of the Woody Mountain Well Field Area, Coconino County, Arizona

      Montgomery, Errol L.; DeWitt, Ronald H.; Northern Arizona University; City of Flagstaff Water Department (Arizona-Nevada Academy of Science, 1975-04-12)
      Conclusions drawn from a water resources study of the woody mountain area are: the average coefficients of transmissibility and of storage of the principal aquifer are approximately 30,000 gpd/ft and 0.05 respectively; drawdown in wells is greater than predicted using theoretical calculations due to the turbulent flow near the well bore in the fractured Coconino aquifer; the computed interference between pumped wells in the field ranges from 10.5 ft. To 19.7 ft. Interference would be negligible between wells spaced at distances greater than 6,000 ft. For pumping periods as long as two hundred days; the negative boundary effect of off-set on the oak creek fault may be balanced by the recharge effect of groundwater located in the highly permeable fractured zone adjacent to the fault; and the quantity of recharge water to the well field is greater than withdrawals from the wells.
    • Assessing the Bare Soil Evaporation Via Surface Temperature Measurements

      Idso, Sherwood B.; Reginato, Robert J.; Jackson, Ray D.; Agricultural Research Service, U.S. Department of Agriculture; ARS, USDA, U. S. Water Conservation Laboratory, Phoenix, Arizona 85040 (Arizona-Nevada Academy of Science, 1975-04-12)
      Evaporation of water from bare soils is an important consideration in the scheduling of many farming operations in both irrigated and dryland agriculture. Accurate predictions of bare soil evaporation can serve as the basis for decisions to increase the acreage planted with a given crop. An alternative is presented to previous approaches to bare soil evaporation estimation by empirically correlating the ratio of daily totals of actual to potential evaporation and the amplitude of the diurnal surface soil temperature wave. Since evaporation is directly related to the surface soil water pressure, the soil thermal inertia technique might be capable of prescribing relative bare soil evaporation rates which, combined with potential evaporation calculations, could allow determination of actual evaporation rates over the entire range of soil drying.
    • Assessing Soil Moisture Remotely

      Reginato, Robert J.; Idso, Sherwood B.; Jackson, Ray D.; Agricultural Research Service, U.S. Department of Agriculture; ARS, USDA, U. S. Water Conservation Laboratory, Phoenix, Arizona 85040 (Arizona-Nevada Academy of Science, 1975-04-12)
      Space-age technology has produced tools which when turned to earthly pursuits can provide information on food and fiber production. Soil moisture has the potential for being remotely assessed, and three techniques for accomplishing this are under study. Two of the methods, reflectance and thermal, are sensitive to the conditions of the bare soil surface. The third technique, microwave emission, appears to have a good potential for assessing soil moisture with depth, because of its greater wavelength.
    • Transformations in Quality of Recharging Effluent in the Santa Cruz River

      Wilson, L. G.; Herbert, R. A.; Ramsey, C. R.; Water Resources Research Center; Department of Soils, Water and Engineering, The University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1975-04-12)
      Since 1955 secondary treated effluent from the city of Tucson treatment plant has been released into the Santa Cruz River, the principal drainage tributary of the Tucson basin. Because the river is ephemeral, it has functioned essentially as an artificial recharge facility for sewage effluent. In past years the total volume of effluent artificially recharged amounted to about 31,000 ac-ft per year. Such recharge has affected not only the groundwater levels in the vicinity of the river, but also water quality. Recharge of nitrate is of particular concern.
    • Aerial Snowpack Mapping

      Warksow, William L.; Salt River Project, Phoenix, Arizona (Arizona-Nevada Academy of Science, 1975-04-12)
      Arizona's continued growth and development depends upon sound management of water resources, especially melted snow which is the primary source of water for the 1.1. Million residents of Maricopa county. The method for snowpack information gathering practiced by watershed specialists of the Salt River project in Arizona is described. The method is outlined, describing aircraft reconnaissance, direct enroute mapping of extent and depth of snowpack, and techniques for identifying ice and/or melt conditions. Under optimal conditions, this technique is considered more than acceptable for determining snowpack levels. Limitations of the technique result from the observer's tolerance of vertigo which can arise under flying conditions; cloud cover, which can reduce contrast and shadows thereby reducing accuracy of observation; and vegetation zones where density of plant matter screens much of the snow.
    • Measuring Snow Cover from ERTS Imagery on the Black River Basin

      Aul, Jerry S.; Ffolliott, Peter F.; School of Renewable Natural Resources, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1975-04-12)
      The possibility of using imagery from the earth resources technology satellites (ERTS) to monitor changes in areal snow cover in east-central Arizona is examined. Four methods were used in the interpretation of areal snow cover from the ERTS imagery, the densitometer, dot grid, squares grid and projection-planimeter methods providing results of 69, 71, 72 and 74 percent of areal cover respectively. No one method for interpretation of ERTS imagery should be ruled unusable, but any use made of ERTS imagery is dependent upon turn-around time for obtaining the imagery, as snow cover information which cannot be obtained within 24 hours is limited in practical application.
    • The Application of Step-Drawdown Pumping Tests for Determining Well Losses in Consolidated Rock Aquifers

      Uhl, V. W., Jr.; Joshi, V. G.; Alpheus, A.; Sharma, G.; Hydrology and Water Resources, University of Arizona, Tucson, Arizona; Evangelical Lutheran Church Water Development Project, Getul, M.P., India (Arizona-Nevada Academy of Science, 1975-04-12)
      The concept of a step -drawdown test was first introduced by Jacob, and further modifications in the technique were made by Rorabaugh. Analysis of step -drawdown test data enables the quantification of the components of drawdown due to formation or aquifer loss, and due to well losses in a pumped well. This technique has been used to test approximately 100 wells that were drilled in crystalline and basalt formations in central India. Test data have been analyzed by Rorabaugh's method and by a graphical method, and the results of a number of tests are presented and discussed. Anomalies in the test analysis often proved helpful for interpreting aquifer irregularities. In general, the well loss constant decreases with an increase in specific capacity and the aquifer loss constant decreases with increasing transmissivity. Significant reductions in specific capacity during a step test occur in wells with high well losses. An attempt is made to quantify the well losses in a consolidated rock well, and a number of practical applications of step -drawdown tests are discussed.
    • Salt Balance in Groundwater of the Tulare Lake Basin, California

      Schmidt, Kenneth D. (Arizona-Nevada Academy of Science, 1975-04-12)
      The Tulare Lake basin at the base of the Sierra Nevada Mountains is the basis for water supply for several cities and a highly productive agricultural area. Little attention has been given to groundwater quality during the past one hundred years. A careful study of the salt balance produced a set of guidelines for future groundwater managers to follow. The major emphasis for future water consumption should be the efficient use of irrigation. This would produce a positive impact on groundwater quality, energy savings, and less imported water would be needed. Groundwater management in the future must consider water quality as well as quantity. Appropriate monitoring programs are urgently needed to provide data on trends in groundwater quality.
    • Economic Adjustment to a New Irrigation Water Source: Pinal County, Arizona and the Central Arizona Project

      Boster, Mark A.; Martin, William E.; Department of Agricultural Economics, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1975-04-12)
      Pinal County is one of Arizona's largest farm and highest farm income areas. Agriculture there is completely dependent upon irrigation systems, with nearly all of the water supply pumped from underlying groundwater reservoirs. Delivery of central Arizona project water will not assure groundwater conservation at a one to one trade-off ratio. Most of the monetary benefits to agriculture derived from the project will be realized by Indian farmers. Cotton acreage will not be affected, but the acreage of small grains and alfalfa will increase. The increasing salinity of cap water should be of no concern to Pinal County farmers.
    • Hydrology and Water Resources in Arizona and the Southwest, Volume 5 (1975)

      Unknown author (Arizona-Nevada Academy of Science, 1975-04-12)
    • Thunderstorm Precipitation Effects on the Rainfall-Erosion Index of the Universal Soil Loss Equation

      Renard, Kenneth G.; Simanton, J. Roger; United States Department of Agriculture, Agricultural Research Service, Western Region, Southwest Watershed Research Center, Tucson, Arizona 85705 (Arizona-Nevada Academy of Science, 1975-04-12)
      The universal soil loss equation (USLE) is widely used for estimating annual and individual storm erosion from field-sized watersheds. Records from a single precipitation gage in climatic areas dominated by thunderstorms can be used to estimate the erosion index (EI) only for the point in question on individual storms or for a specific annual value. Extrapolating the results for more than about a mile leads to serious error in estimating the erosion by the use of the USLE. Short time intervals must be used to obtain an adequate estimate of the EI when using the USLE. The variability of the annual EI can be approximated with a log-normal distribution. All studies indicated that investigations are needed to facilitate estimating the average annual EI from precipitation data as reported by state climatological summaries for states west of the 104th meridian. Additional work is needed to facilitate estimating the EI value from the precipitation data available in most areas of the southwest where thunderstorms dominate the rainfall pattern.
    • Application of Bayesian Decision Theory in Well Field Design

      Bostock, Charles A.; Davis, Donald R.; Department of Hydrology & Water Resources, University of Arizona, Tucson 85721; Hydrology & Water Resources, and Systems and Industrial Engineering, University of Arizona, Tucson 85721 (Arizona-Nevada Academy of Science, 1975-04-12)
      Bayesian decision theory is a method for comparing expected utilities of alternative actions given various possible states of nature. The method treats uncertainty as to the true state of nature by determining the expected utility of each action in terms of the probabilities of the various possible states. The decision rule is to choose the action having the best expected utility. This paper illustrates an application of Bayesian decision theory in a well field design problem where a decision had to be made regarding capacity-density combination for wells located in an extensive uniform grid. The uncertainty lay in anticipating the frequencies of transmissivity values among the wells.