• Aspects of Aquifer Test Error Analysis

      Benbarka, Ahmed M.; Davis, Donald R.; Department of Hydrology and Water Resources, University of Arizona (Arizona-Nevada Academy of Science, 1981-05-02)
      Errors in the estimation of the aquifer parameters T and S derived from aquifer test data are examined as to their cause and effects. The analysis is based on the Theis equation. The basic causes of error are in the measurements of drawdown and pumping rate, in fitting the model to the data and in violations of model assumptions. Measurement errors were studied experimentally. Curve fittings by hydrologists were compared to "automatic" curve fittings obtained by nonlinear regression. The covariance matrix of T and S obtained in this manner was used, in conjunction with sensitivity analysis, to estimate the error in prediction of future drawdown. While automatic fitting is not a perfect substitute for graphical fitting, there is a definite relation between the two methods which allows the use of the statistics developed by nonlinear regression theory to be used to study the cause, effects and risks inherent in aquifer analysis.
    • Toward Development of a Groundwater Quality Protection Strategy for Arizona

      Bennett, Marc M.; Stephenson, Larry K.; Arizona Department of Health Services, Phoenix, Arizona 85007; University of Phoenix, Phoenix, Arizona 85004 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Hydraulic Effects of Vegetation Changes Along the Santa Cruz River Channel Near Tumacacori, Arizona

      Applegate, Lee H.; U.S. Geological Survey, Tucson, Arizona 85701 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Rainwater Quality in Southeastern Arizona Rangeland

      Osborn, Herbert B.; Cooper, Loel R.; Billings, Jeff; USDA-SEA Southwest Rangeland Watershed Research Center, Tucson, Arizona (Arizona-Nevada Academy of Science, 1981-05-02)
    • Use of the Universal Soil Loss Equation in the Tropics

      Rasmussen, Todd C.; Tracy, Fred C.; Department of Hydrology and School of Renewable Natural Resources, University of Arizona 85721 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Evaluation of the Use of Soil Conservation Service Snow Course Data in Describing Local Snow Conditions in Arizona Forests

      Gottfried, Gerald J.; Ffolliott, Peter F.; USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Forestry Sciences Laboratory, Arizona State University, Tempe, Arizona 85281; School of Renewable Natural Resources, University of Arizona, Tucson, Arizona 85721 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Point-Area-Frequency Conversions for Summer Rainfall in Southeastern Arizona

      Osborn, Herbert B.; Lane, Leonard J. (Arizona-Nevada Academy of Science, 1981-05-02)
    • An Analysis of Recession Flows from Different Vegetation Types

      Sulaiman, Wan Norazmin bin; Ffolliott, Peter F.; School of Renewable Natural Resources, University of Arizona (Arizona-Nevada Academy of Science, 1981-05-02)
    • The Alternatives and Impacts Associated with a Future Water Source Transition for Tucson Water

      McLean, Thomas M.; Davis, Stephen E.; Tucson Water, Tucson, Arizona 85726 (Arizona-Nevada Academy of Science, 1981-05-02)
      Anticipating a surge in the future growth of the Tucson urban area accompanied by a need for the preservation of the local groundwater resource, Tucson Water is planning for a major transition in its source of supply during the next fifty years. The completion of the Central Arizona Project to the Tucson area represents the primary ingredient to the formulation of a future water supply plan for the community. Tucson, which presently relies totally upon groundwater for its potable water supply, is diligently preparing to accept its first surface water source. The task of planning for this event is extremely complex and is further hampered by the fact that many critical factors relating to the Tucson Division of the Central Arizona Project are yet undefined. Tucson Water engineers utilize contemporary computerized hydraulic models as tools to define an array of technical solutions to the problem of accomplishing a major conversion from a multi-point system source to a predominantly single source of supply. Elements such as construction, operation, and maintenance costs associated with water treatment and delivery systems are addressed.
    • Water Yield Opportunities on National Forest Lands in Arizona

      Solomon, Rhey M.; Schmidt, Larry J.; USDA Forest Service, Albuquerque, New Mexico (Arizona-Nevada Academy of Science, 1981-05-02)
      Water Yield improvement opportunities were estimated for National Forest lands in Arizona. The land base available for treatment was reduced in a stepwise manner to account for administrative, climatic, and ownership constraints. Research relationships were built upon, and then applied to the remaining land base to project water yield estimates. A continuum of management prescriptions was then displayed to show the range of opportunities. Only the chaparral, ponderosa pine, and mixed conifer types show opportunities of significance. Water yield increases can be realized principally from conversion of chaparral to grass and could add an additional 25 to 70 thousand acre-feet. The ponderosa pine zone could add an additional 15 to 30 thousand acre-feet with intensive management by reducing stocking levels on the commercial National Forest lands. Little opportunity exists within the mixed conifer zone and increases would amount to less than 10 thousand acre -feet. Annual contributions of National Forest lands are likely to range from 40 thousand to 100 thousand acre feet; this will be highly variable depending upon precipitation quantities.
    • Nutrient Levels on the Verde River Watershed with Recommended Standards for P and N

      Love, Timothy D.; Arizona Department of Health Services, Phoenix, Arizona 85007 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Estimating Potential Evapotranspiration in Arid Environments

      Osmolski, Z.; Gay, L. W.; School of Renewable Natural Resources, University of Arizona, Tucson, Arizona 85721 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Geostatistical Analysis and Inverse Modeling of the Avra Valley Aquifer

      Clifton, Peter M.; Neuman, Shlomo P.; Arizona Department of Water Resources, Phoenix, Arizona 85004 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Some Effects of Controlled Burning on Surface Water Quality

      Sims, Bruce D.; Lehman, Gordon S.; Ffolliott, Peter F.; School of Renewable Natural Resources, University of Arizona (Arizona-Nevada Academy of Science, 1981-05-02)
    • Federal Reserved Water Rights of the Bureau of Land Management in Colorado

      Herbert, Richard A.; Martinez, Anthony L.; Bureau of Land Management, Denver, Colorado 80202 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Organic Pollutants in Ground-Recharged Water

      Mikita, Michael A.; Thorn, Kevin; Hobson, James; Lo, Suzanne; Steelink, Cornelius; Department of Chemistry, University of Arizona, Tucson, Arizona 85721 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Sediment Sources of Midwestern Surface Waters

      Wilkin, Donovan C.; Hebel, Susan J.; School of Renewable Natural Resources, University of Arizona; Department of Landscape Architecture, University of Illinois (Arizona-Nevada Academy of Science, 1981-05-02)
    • Relationships of Soil Texture with Soil water Content and Soil Porosity Characteristics of Arizona Soils

      Post, Donald F.; Department of Soils, Water and Engineering, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1981-05-02)
    • Arizona Ground-Water Reform: Forces and Consequences of Change in State Water Policy

      Marsh, Floyd L.; Hensen, Scott A.; Department of Hydrology and Water Resources, University of Arizona, 85721; Department of Political Science, University of Arizona 85721 (Arizona-Nevada Academy of Science, 1981-05-02)
    • Use of Bacterial Indicators in Assessment of Water Quality of the East Verde River

      Athey, Patrick V.; Urbina, Marilyn J.; Sommerfield, Milton R.; Department of Botany and Microbiology, Arizona State University, Tempe, Arizona 85281 (Arizona-Nevada Academy of Science, 1981-05-02)