• Bed Material Characteristics and Transmissions Losses in an Ephemeral Stream

      Murphey, J. B.; Lane, L. J.; Diskin, M. H.; Southwest Watershed Research Center, Agricultural Research Service, USDA, Soil and Water Conservation Research Division; Arizona Agricultural Experiment Station, Tucson (Arizona-Nevada Academy of Science, 1972-05-06)
      An average of 6 to 13 streamflows from intense summer convective storms occurs annually in the walnut gulch experimental station, 58 square miles in southeastern Arizona. Flows last generally less than 6 hours, and the channels are dry 99 percent of the time. The limiting factors imposed by the geology and geomorphology of the channel to transmission losses of a 6 square mile channel in the station are described. The Precambrian to quaternary geology is outlined, and geomorphology of the channels are described. Volume, porosity and specific yield of alluvium were determined. There is 106 acre-feet of alluvium with a mean specific yield of 28 percent, and a maximum water absorbing capacity of 29 acre-feet or 7 acre-feet per mile of reach. Channel slope is insensitive to changes in geological material beneath it or to changes in flow regime. Channel cross section is highly sensitive to geology and flow regime. Transmission losses were highly correlated to volume of inflow.
    • Role of Modern Methods of Data Analysis for Interpretation of Hydrologic Data in Arizona

      Kisiel, Chester C.; Duckstein, Lucien; Fogel, Martin M.; Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona 85721; Department of Systems and Industrial Engineering | Department of Watershed Management (Arizona-Nevada Academy of Science, 1972-05-06)
      Mathematical models, requiring substantial data, of hydrologic and water resources systems are under intensive investigation. The processes of data analysis and model building are interrelated so that models may be used to forecast for scientific reasons or decision making. Examples are drawn from research on modeling aquifers, watersheds, streamflow and precipitation in Arizona. Classes of problems include model choice, parameter estimates, initial condition, input identification, forecasting, valuation, control, presence of multiple objectives, and uncertainty. Classes of data analysis include correlation methods, system identification, stationarity, independence or randomness, seasonality, event based approach, fitting of probability distributions, and analysis for runs, range and crossing levels. Time series, event based and regression methods are reviewed. The issues discussed are applied to tree-ring analyses, streamflow gaging stations, and digital modeling of small watersheds and the Tucson aquifers.
    • Groundwater Contamination in the Cortaro Area, Pima County, Arizona

      Schmidt, Kenneth D.; Harshbarger and Associates, Tucson, Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      High concentrations of nitrate have been found in water samples from irrigation wells north of the Tucson Arizona sewage treatment plant. The plant, which had primary treatment prior to 1951, produced 2,800 acre-feet of effluent in 1940, 4,600 acre-feet in 1950, 16,300 acre-feet in 1960, and 33,000 acre-feet in 1970. Large amounts of treated effluent recharge the groundwater system north of the plant. Sources of nitrate contamination beside sewage effluent may be sewage lagoons, sanitary landfills, meat packing and dairy effluent, septic tanks, and agricultural runoff. Sewage effluent is considered to be the primary source of nitrate contamination in the area. Geologic and flow net analysis indicate that aquifer conditions minimize the effects of sewage effluent contamination. Chloride and nitrate migration appears to be similar in the aquifer. Large-capacity wells were sampled to reflect regional conditions, and chemical hydrographs of chloride and nitrate were analyzed. The seasonal nature of these hydrographs patterns depend on total nitrogen in sewage effluent. Management alternatives are suggested to decrease nitrate pollution by sewage effluent.
    • Transmissivity Distribution in the Tucson Basin Aquifer

      Supkow, D. J.; Department of Hydrology and Water Resources, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      The distribution of transmissivity within the Tucson basin aquifer, as determined by pumping tests and reviewed in the construction of a digital model of the aquifer, was not totally random in space. Data tended to be distributed normally or log-normally for biased samples of developed wells. A frequency distribution of transmissivity derived from a calibrated digital model is more nearly representative of the real world because the aquifer sample is without bias as the sample constitutes the entire aquifer. Geohydrologic setting, electric analog, and digital models of the basin are discussed. The theory of transmissivity distribution in an arid land alluvial aquifer is developed from Horton's laws of exponential relationship between stream order and drainage network parameters. It is hypothesized that there is an exponential relationship between transmissivity of an alluvial aquifer. A statistical study was made of values derived from the digital model to test the probability density function hypothesized for transmissivity. The mean value is a function of climate and drainage area. These hypotheses require further validation.
    • Color It Evaporation

      Dvoracek, M. J.; Department of Hydrology and Water Resources, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      Evaporation is a major hydrologic process in arid and semiarid lands. A brief review of evaporation literature indicates that a unique parameter, color, is desirable. Artificially colored water was used in a west Texas experiment to monitor evaporation rate and to note the effect of color on evaporation. Artificially green water had a higher evaporation rate than sewage and runoff. Five different colored waters were studied from 1966 to 1970. Color seems to affect the amount of adsorbed radiation as well as the extent of black radiation. The trend for a higher daily rate of evaporation existed for colored waters except during periods of low air temperature. Seven graphs are presented to support these conclusions.
    • Input Specifications to a Stochastic Decision Model

      Clainos, D. M.; Duckstein, L.; Roefs, T. G.; Systems and Industrial Engineering Department, University of Arizona; Hydrology and Water Resources Department, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      The use of discrete conditional dependency matrices as input to stochastic decision models is examined. Some of the problems and initial assumptions involved with the construction of the above mentioned matrices are discussed. Covered in considerable detail is the transform used to relate the gamma space with the normal space. A new transform is introduced that should produce reasonable results when the record of streamflow (data) has a highly skewed distribution. Finally, the possibility of using the matrices to provide realistic inputs to a stochastic dynamic program is discussed.
    • An Investigation of Colorado River Trips: A User Study

      Boster, Mark A.; Gum, Russell L.; Department of Hydrology and Water Resources, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      Increased useer intensity of the Colorado River through Grand Canyon National Park and Monument required the national park service and the Colorado River outfitters association to adopt new policies to improve the quality of river trips and to protect the river. This study was undertaken to gain a greater awareness and understanding of visitor expectations, perceptions, interactions, satisfactions and dissatisfactions by analysis of response to a questionnaire mailed to a random sample of 2,622 past river runners from which a 65 percent return was received. Analysis of individual question tabulation and multivariate data-cluster analysis were performed. Users found crowding or user density to be at least tolerable. The largest group of runners were average in wilderness or other activities, and low relative to less strenuous activities. A large group of runners had relatively little experience in the wilderness. A large group of runners enjoyed the trip, desired more regulations, and were moderate about taking more trips. A large group rated the trip as a wilderness adventure which provided the opportunity to 'get away'. Cluster analysis is shown to be a useful tool of policy-making institutions.
    • Nitrogen Species Transformations of Sewage Effluent Releases in a Desert Stream Channel

      Sebenik, P. G.; Cluff, C. B.; DeCook, K. J.; Water Resources Research Center, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      A preliminary study was made with the objective of examining nitrogen species transformations of treated sewage effluent releases within the channel of an ephemeral stream, the Santa Cruz River of southern Arizona. Water quality samples were taken at established locations in sequence so that peak daily flows could be traced as the effluent moved downstream. Results indicate that increased nitrification, coinciding with changing stream characteristics, starts in the vicinity of Cortaro Road (6.3 river miles from the Tucson Sewage Treatment Plant discharge). Through physical-chemical changes in streamflow, nitrate -nitrogen values reach a maximum at approximately 90-95 percent and 60-80 percent of total flow distance for low flows and high flows, respectively. Concentrations of ammonia-nitrogen and total nitrogen decrease continuously downstream with both high and low flows. Therefore, the rate of nitrification within sewage effluent releases in a desert stream channel evidently is related to flow distance and physical characteristics of the stream.
    • A Proposed Model for Flood Routing in Abstracting Ephemeral Channels

      Lane, Leonard J.; Soil and Water Conservation Research Division, Agricultural Research Service, USDA; Arizona Agricultural Experiment Station, Tucson, Arizona; Southwest Watershed Research Center, Tucson, Arizona 85705 (Arizona-Nevada Academy of Science, 1972-05-06)
      Almost all runoff from semiarid rangeland watersheds in southern Arizona results from intense highly variable thunderstorm rainfall. Abstractions, or transmission losses, are important in diminishing streamflow, supporting riparian vegetation and providing natural groundwater recharge. A flood routing procedure is developed using data from the walnut gulch experimental watershed, where flood movement and transmission losses are represented by a system using storage in the channel reach as a state variable which determines loss rates. Abstractions are computed as a cascade of general components in linear form. Wide variation in the parameters of this linear model with increasing inflow indicates that a linear relation between losses and storage is probably incorrect for ephemeral channels.
    • Water Disposition in Ephemeral Stream Channels

      Sammis, T. W.; Hydrology and Water Resources, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      The contribution of flows from small watersheds to groundwater recharge is of interest. Water disposition depends on infiltration and evaporation characteristics. This study had the objective of developing an infiltration equation for estimating transmission losses during a flow event in an ephemeral stream near Tucson, Arizona, in the rocky mountain forest and range experiment station. Palo Verde, desert hackberry, cholla, marmontea and mesquite are the major bank species of the sandy channels. A climatic section consisting of a hydrothermograph recording rain gage and class a evaporation pan was installed. A water balance method was used to estimate evapotranspiration. A specially designed infiltrometer was used to simulate flow events. The data allowed the following conclusions: Philip's infiltration equation is an excellent mathematical model, initial moisture affects initial infiltration rate, the Philip coefficients are determinable by the infiltrometer constructed, soil moisture affects infiltration rates, and transpiration rates diminish linearly proportional to the ratio of available water to field capacity.
    • Saline and Organic Water Pollution

      Bohn, Hinrich L.; Johnson, Gordon V.; Department of Soils, Water and Engineering, University of Arizona, Tucson, Arizona, 85721 (Arizona-Nevada Academy of Science, 1972-05-06)
      Better use and recycling of fresh water, which often recharges the oceans, would reduce man's disruption of nature to increase his supply of potable water. The global distribution of water, desalination, water reclamation and recycling, the roles of soils and plants in recycling and urban misuse of water are discussed. Man can increase his supply of food and good fresh water by recycling and nutrient balance, which imply living off his wastes. Intimate involvement of soils and plants in the production of fresh water and food is clear. Soils and plants should be equally involved in converting our waste water into potable water and useful nutrients. Numerous examples of how this may be done and how it is being done are presented.
    • A Solution to Small Sample Bias in Flood Estimation

      Metler, William; Systems & Industrial Engineering, University of Arizona, Tucson, Arizona 85721 (Arizona-Nevada Academy of Science, 1972-05-06)
      In order to design culverts and bridges, it is necessary to compute an estimate of the design flood. Regionalization of flows by regression analysis is currently the method advocated by the U.S. Geological Survey to provide an estimate of the culvert and bridge design floods. In the regression analysis a set of simultaneous equations is solved for the regression coefficients which will be used to compute a design flood prediction for a construction site. The dependent variables in the set of simultaneous equations are the historical estimates of the design flood computed from the historical records of gaged sites in a region. If a log normal distribution of the annual peak flows is assumed, then the historical estimate of the design flood for site i may be computed by the normal as log Q(d,i) = x(i) + k(d)s(i). However because of the relatively small samples of peak flows commonly used in this problem, this paper shows that the historical estimate should be computed by to log Q(d,i) = X(i) + t(d,n-1) √((n+1)/n) s(i) where t(d,n-1) is obtained from tables of the Student's t. This t-estimate when used as input to the regression analysis provides a more realistic prediction in light of the small sample size, than the estimate yielded by the normal.
    • Hydrology as a Science?

      Dvoracek, M. J.; Evans, D. D.; Department of Hydrology and Water Resources, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      Experimental and historical development of the systematic study of water is briefly reviewed to prove hydrology a science. The hydrology program at the university of Arizona is outlined, and details of the course 'water and the environment' are expounded. This introductory course is intended for non-scientific oriented students at this southwestern university. A reading list is provided for the class, and scientifically designed laboratory experiments are developed. The first semester includes discussion of world water inventory; occurrence of water; hydrologic cycle; interaction of oceanography, meteorology, geology, biology, glaciology, geomorphology and soils; properties of water (physical, biological, chemical), and resources development. The second semester discusses municipal, industrial and agricultural water requirements, surface, ground, imported and effluent water resources management; water law; economic, legal, political, and social water resource planning; ecological impact; patterns of use; and survival of man. Mathematical problems are reviewed along with ecological orientation of students.
    • Effect of a Grass and Soil Filter on Tucson Urban Runoff: A Preliminary Evaluation

      Popkin, Barney Paul; Water Resources Research Center, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      Storm runoff from the Tucson metropolitan area is unsuitable for most uses without processing. A lysimeter comprised of a grass and soil filter was constructed and is being evaluated as a water-quality treatment facility. The lysimeter is 200 feet long, 4 feet wide and 5 feet deep, and contains homogeneous calcareous loam covered by common grasses. Experimental apparatus was installed to divert less than a cubic foot per second of runoff from urbanized Arcadia Watershed. Runoff flows by gravity over the lysimeter, where surface inflow, surface outflow and subsurface outflow are measured and sampled. Four trials, each associated with a discrete runoff event, were conducted in the fall of 1971. Water samples were analyzed for inorganic chemical constituents, chemical oxygen demand (COD), coliforms, turbidity and sediment contents. Subsurface-outflow samples from initial trials were high in COD and total dissolved solids, representing soil flushing or leaching. Concentrations of inorganics reached a maximum value within a few hours of initial seepage, and then decreased. The peaking represents a salt build-up between trials. Concentrations of COD, coliforms, turbidity and sediment in subsurface-outflow samples decreased significantly during each trial. Surface-outflow samples had lower turbidity, COD, bacteria and sediment contents than surface-inflow samples. Turbidity, suspended and volatile solids, coliforms and COD in runoff samples may be reduced by grass and soil filtration. Increased grass development and soil settling work to produce a better quality effluent. Quantification of the lysimeter's effectiveness will be useful for urban watershed management.
    • An Analysis of Yearly Differences in Snowpack Inventory-Prediction Relationships

      Ffolliott, Peter F.; Thorud, David B.; Enz, Richard W.; Department of Watershed Management, University of Arizona, Tucson 85721; USDA Soil Conservation Service, Phoenix, Arizona 85025 (Arizona-Nevada Academy of Science, 1972-05-06)
      Inventory-prediction relationships between snowpack conditions and forest attributes may be useful in estimating water yields derived from snow, but such relationships are developed usually from source data collected over a short time period. Analyses of long-term data suggest inventory-prediction relationships developed from limited data may have more general application, however. Available records from 18 snow courses in the ponderosa pine type in Arizona provided source data in this study, which was designed to empirically analyze inventory-prediction relationships developed from long-term snow survey records. The primary hypothesis tested and evaluated by statistically analyzing the family of regression equations representing a snow course, was that, given a precipitation input, the distribution of snowpack water equivalent at peak seasonal accumulation is determined by the spatial arrangement of the forest cover, e.g. basal area. Generally 12 of the 18 snow courses evaluated appeared to support the hypothesis, three courses did not, and three courses were considered inconclusive.
    • Evaluation of a Turfgrass - Soil System to Utilize and Purify Municipal Waste Water

      Sidle, R. C.; Johnson, G. V.; Department of Soils, Water and Engineering, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      Sewage effluent for irrigation is well established. This study determines the capacity of selective turfgrass-soil systems to purify municipal sewage effluent and to measure the degree of utilization of nitrogen in the effluent by turfgrass. Chlorinated secondarily treated sewage effluent from the city of Tucson was applied to turfgrass grown on sandy loam, silt and loam, under three levels of irrigation under laboratory conditions of duplicate pots. Each pot had 2 suction probes to estimate soil moisture tensions and to allow soil water sampling. The study operated from September to March, 1972, for 30 weeks. Purification efficiency, nitrogen utilization and percent recharge were calculated. Turfgrass can be irrigated with sewage effluent at common rates without hazard of nitrogen pollution to groundwater. Purification efficiency exceeded 90 percent for all irrigation levels on sandy loam and silt. Nitrogen utilization was greater over sandy loam. Turfgrass-soil systems can utilize nitrogen and purify waste water.
    • Some Legal Problems of Urban Runoff

      Holub, Hugh; College of Law, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1972-05-06)
      Pressure is being brought to bear on national resources of air, earth, and water in the growing cities in the arid southwest. Legal questions involved in capturing urban runoff and putting it to a beneficial use are examined. Urbanization of a watershed results in a 3 to 5 fold increase in runoff amounts. Legal aspects include tort liability from floods, water rights to the increased flows, land use restrictions along banks and flood plains, condemnation of land for park development and flowage easements, financing problems, zoning applications, and coordination of governmental bodies responsible for parks, storm drainage and related services. Urban runoff is the most obvious legal problem in the tort liability area. It appears feasible to divert small quantities of water from urban wastes for recreational uses which provide flood control benefits. It appears that municipalities could appropriate increased flows caused by urbanization. The ultimate legal questions remain to be resolved by legislation, litigation or extension of the appropriative system.
    • The Groundwater Supply of Little Chino Valley

      Matlock, W. G.; Davis, P. R.; Soils, Water and Engineering Department, The University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      The little chino valley in central Arizona presents an interesting groundwater study as withdrawals exceed recharge. The groundwater surface is falling at about 2 feet per year over most of the area due to large irrigation development. A shallow water table aquifer overlies the artesian aquifer and receives recharge from irrigation runoff. Water quality in the artesian aquifer is excellent. Water quality in the water-table aquifer is poorer, being somewhat higher in total salts, but is suitable for most domestic and agricultural uses. Specific yield for the supply area to the artesian aquifer is 12 percent, with estimated annual recharge of 4000 acre feet and leakage from the aquifer of 2300 acre feet. Water budget and use for the basin is presented with water level and water quality data. The multiphase aquifer system is described and illustrated.
    • Design and Pilot Study of an Arizona Water Information System

      Foster, K. E.; Johnson, J. D.; Office of Arid Land Studies, University of Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      Water information systems may have different demands, such as responding to queries about rainfall-runoff relationships, water level data, water quality data and water use. Data required for retrieval may need display, such as a hydrograph. Information systems are reviewed and results of specific water information agencies are reported. Agencies in Arizona are listed with their specific water information need. Development of a water activity file and water information system is outlined for Arizona as a pilot project. Linkage of units within the data system is shown, as is the information system's questionnaire to project leaders. Information currently in the system includes water quality from the state department of health for 450 wells in the Tucson basin, and water level, storage, storage coefficient and transmissivity supplied by the Arizona water commission for the Tucson basin and Avra Valley. Quality of data submitted to the system should be reflected in retrieval for better understanding of the data. This consideration is planned for the coming fiscal year.
    • Objective and Subjective Analysis of Transition Probabilities of Monthly Flow on an Ephemeral Stream

      Dvoranchik, William; Duckstein, Lucien; Kisiel, Chester C.; Department of Systems and Industrial Engineering, University of Arizona; Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1972-05-06)
      A critique of statistical properties of monthly flows on an ephemeral stream in Arizona is given. A subjective procedure, justified for managerial purposes not concerned with the variability of flow within the month, is proposed for sequential generation of monthly flow data. Ephemeral flows should be modeled by starting with at least historical daily flows for more meaningful monthly flow models. Stochastic properties of monthly streamflows and state transition probabilities are reviewed with regard to ephemeral streams. A flow chart for a streamflow model geared to digital computers, with a simulation of streamflow subroutine, is developed. Meaningful monthly flow models could serve as a check on alternative models (subjective matrix, lag-one auto regressive, harmonic, bivariate normal, bivariate log-normal models). Rules and guidelines are presented in developing meaningful probability matrices.