• 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.
    • 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.
    • The Effect of an Intensive Summer Thunderstorm on a Semiarid Urbanized Watershed

      Boyer, D. G.; DeCook, K. J.; Water Resources Research Center, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
      The University of Arizona Atterbury Experimental Watershed, located southeast of Tucson, Arizona has been instrumented for precipitation and runoff measurements since 1956. Early on the afternoon of July 16, 1975 an intense convective thunderstorm produced more than three inches of rainfall in less than 50 minutes as recorded in several rain gages located in the middle of one 8.1 square-mile desert subwatershed. Storm runoff from this rural subwatershed and an adjacent recently urbanized subwatershed filled the newly finished Lakeside Reservoir and topped the concrete flood spillway with a peak of greater than 3000 cfs, the greatest flow since monitoring began. An analysis of storm characteristics, along with previously available data from local urbanized watersheds, allows speculation on the effect of such an intensive storm in a highly urbanized area.
    • Use of Satellite Data to Develop Snowmelt-Runoff Forecasts in Arizona

      Ffolliott, Peter F.; Rasmussen, William O.; School of Renewable Natural Resources, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
    • Simulation of Partial Area Response from a Small Semiarid Watershed

      Lane, Leonard J.; Wallace, Delmer E.; Southwest Watershed Research Center, Tucson, Arizona 85705 (Arizona-Nevada Academy of Science, 1976-05-01)
    • 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.
    • Academic Training for Groundwater Quality Specialists

      Schmidt, Kenneth D. (Arizona-Nevada Academy of Science, 1976-05-01)
    • Addition of a Carbon Pulse to Stimulate Denitrification in Soil Columns Flooded with Sewage Water

      Lance, J. C.; Gilbert, R. G.; U. S. Water Conservation Laboratory, Phoenix, Arizona 85040 (Arizona-Nevada Academy of Science, 1976-05-01)
    • Erosion and Sedimentation in the Upper Gila Drainage, A Case Study

      Kingston, R. L.; Solomon, R. M.; Gila National Forest, Silver City, New Mexico (Arizona-Nevada Academy of Science, 1976-05-01)
      The upper Gila River in Arizona and New Mexico contains extremely diverse geology and soils. One geological formation that is somewhat unique to the Southwest and the upper Gila drainage is the Gila Conglomerate formation. In New Mexico, this conglomerate is extensive on the main Gila River drainage, accounting for over 35 percent of the main basin area. A case study was done on the 22,580 hectare (55,793 acres) Lake Roberts Watershed to assess the current sedimentation problem and its sources. This study revealed interesting patterns of lake surface area changes with volume changes of the original 28.3 hectare (70 acres) man-made reservoir over the last 12 years. Surface area reduction (19%) has progressed at a rate over twice that for volume reduction (9%). The source of the problem stems primarily from soils derived from highly sensitive Gila Conglomerate. The watershed is not uncharacteristic of the unique geology and soils typical of the upper Gila drainage and may furnish insight into sediment production and sources for much of the Gila headwater drainage in New Mexico.
    • 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.
    • Water Quality of Streamflow from Forested Watersheds on Sedimentary Soils

      Gregory, Paul W.; Ffolliott, Peter F.; School of Renewable Natural Resources, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
      To provide quantitative baseline information on water quality of streamflow from ponderosa pine watersheds on sedimentary soils, water samples were collected at the mouths of four watersheds at time of surface runoff and during extreme or unusual hydrological events. In each sample, calcium (Ca++), magnesium (Mg++) and sodium (Na+) were determined by using atomic absorption spectrophotometry; carbonate (CO=3) and bicarbonate (HCO-3) were measured by titrating with standard acid; fluoride (F-), sulfate (SO=4), 3 nitrate (NO-3), and chloride (Cl-) were determined by colorimetric methods using an Autoanalyzer; hydrogen ion concentration (pH) was measured by using a glass electrode; and suspended sediment concentrations were determined by filtration. The data obtained were compared with EPA water quality standards for aquatic life, irrigation, and public water supply. Although the EPA levels of acceptability have not been established for many of the chemical and physical water constituents, the parameters determined in this study, in general, fall within the EPA prescribed limits.
    • 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.
    • Water Quality Study of Lake Havasu, Arizona Near the CAP Intake Area

      Ince, Simon; Kreamer, David L.; Young, Don W.; Constant, Charles L.; Department of Hydrology and Water Resources, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
      Throughout 1974 and 1975 the Department of Hydrology and Water Resources, University of Arizona, conducted a water quality study on Lake Havasu, Arizona, near the Central Arizona Project intake. This investigation was funded jointly by the Arizona Water Commission and the U.S. Bureau of Reclamation. The University study evaluated the hydrography and hydrology, sediments, turbidity, temperature, chemistry, dissolved oxygen (and biochemical oxygen demand), benthic invertebrates, phytoplankton, zooplankton, biomass analysis, and electrical conductivity to establish baseline data for the CAP intake area. The results showed weak stratification and generally good aeration in the lake and high turbidity in the Bill Williams River. Biological quality was good with low amounts of benthics and numerous zooplankton and phytoplankton species. The extensive data from chemical analysis generally conformed to public health standards.
    • Evaluating Water Quality Sampling Schedules Using Fecal Coliform Concentrations in Sabino Creek

      Motschall, Robert M.; Brickler, Stanley K.; Phillips, Robert A.; School of Renewable Natural Resources, University of Arizona, Tucson, Arizona; Civil Engineering, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1976-05-01)
      Sabino Canyon Recreation Area, adjacent to Tucson, and a major water-based recreation complex within the Santa Catalina Mountains, Coronado National Forest, receives intensive recreational use. This natural water resource area with primary water contact activities was monitored for fecal coliform in accordance with U.S. Forest Service Regulation (FSM 2542.2). As part of a larger study, this report discusses the relationships between time, day, and location of sampling with fecal coliform bacterial concentrations in Sabino Creek. Analysis of Variance shows that fecal coliform concentrations were higher: 1) on Sunday than Wednesday, 2) at 4:00PM than 8:00AM or 12:00 Noon, and 3) in the lower section of the four miles of the study area. This research provides the U.S. Forest Service with baseline water quality data and a benchmark from which to continue an efficient water quality monitoring program.
    • 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.
    • Water-Related Information Sources: Highlights

      White, Linda M.; Center for Quantitative Studies, The University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
    • The Role of the States in Control of Weather Modification

      Davis, Ray Jay; College of Law, the University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1976-05-01)
      It now appears that, at least for the near future, the only federal controls of weather modification will be the record keeping and reporting requirements of the National Oceanic and Atmospheric Administration. About two-thirds of the states have enacted cloud seeding laws to fill the regulatory void. These statutes, however, are quite varied and many of them are inadequate. Accordingly, there is a need for "suggested" or "model" state weather control legislation. In a project funded by the Office of Water Research and Technology and administered through the Arizona Water Resources Research Center, such a proposed law has been prepared. It delegates means of control over seeding to an administrative agency, authorizes governmental funding of operations, establishes procedures and criteria for professional licensing of cloud seeders, creates a system for regulation of projects through operational permits, requires record keeping and reporting, and sets standards for resolution of water rights and legal liability issues.
    • NAIWMC - Potential in the Southwest

      Keyes, Conrad G., Jr.; North American Interstate Weather Modification Council, Las Cruces, New Mexico 88003 (Arizona-Nevada Academy of Science, 1976-05-01)
      The North American Interstate Weather Modification Council was formed to coordinate intrastate, interstate and possible international weather modification activities. The main purpose of this organization is to achieve and maintain state and local control of such activities while endeavoring to attain a high degree of legislative uniformity and an effective information exchange mechanism. The need, goals and objectives of the newly created Council are summarized. A summary of the Council's progress at performing the purposes of the Council are presented in this paper. The potential use of this Council in the Southwest is described in relation to existing programs in weather modification in the area.
    • 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.
    • The Prejudices, Polemics, and Politics of Water Management Versus the Reasonable Man Test

      Stribling, Barbara A. (Arizona-Nevada Academy of Science, 1976-05-01)
      American legislative bodies and juries of laymen are founded on the concept that what a reasonable man would do is what will be done. In actuality the synergistic effects of prejudice, politics, and polarized language rarely allow this to occur. The result has been conflict of interest statutorily mandated on natural resource governing boards and a lack of expertise in the courtroom. Further contempt has developed between citizen and expert and between legislator and bureaucrat. I propose to explore the operative mechanism in the situation and discuss possible future roles for both citizen and expert as well as tools which could be utilized by them.