Now showing items 14790-14809 of 14977

    • Water quality analyses of the recreational waters of Sabino and Bear Creeks

      Motschall, Robert Michael,1950-; Brickler, Stanley K. (The University of Arizona., 1976)
      Sabino Canyon Recreation Area has received over 600,000 visitors per year. Sabino and Bear Creeks flow through the area creating a diverse habitat for vegetation and wildlife, and a unique desert setting for water-based recreation. Proximity to the city of Tucson places constant user pressure on the water resources and prime concern in a water-based recreation area is water quality. An intensive study of existing water quality status of Sabino and Bear Creeks was conducted because the quality of water in Sabino and Bear Creeks was unknown. This study examines bacterial, chemical, and physical parameters. Data were collected twice a week on Sundays and Wednesdays for a year. Results of the study indicate there were: (1) no major chemical problems, (2) highest turbidity values occurred during the warm weather months, and (3) high concentrations of fecal coliform in the bottom sediment and periodically in overlying water indicate major sources of fecal contamination have access into Sabino Creek. This study provides the United States Forest Service with baseline water quality data and a benchmark from which to continue an efficient water quality monitoring program.
    • Water quality and bottom sediment in Rillito Creek and selected tributaries in Tucson, Arizona

      Hawkins, Richard H.; Tadayon, Saeid, 1957- (The University of Arizona., 1993)
      In 1986, a monitoring plan was developed to collect baseline data on the physical and chemistry of surface water, ground water, and bottom sediment in Rillito Creek and selected tributaries. Several total trace elements exceeded the U.S. Environmental Protection Agency's primary and secondary maximum contaminant levels for drinking-water standards. When the sediment is removed, none of the constituents in surface water exceed the drinking-water standards; therefore, adsorption by sediment particles plays a vital role in increasing the concentrations of constituents. The presence of the priority pollutants and pesticides in surface water and bottom sediment is probably due to a higher intensity of urbanization and the type of land use within the Alamo Wash and Rillito Creek watersheds. Maximum concentrations of 25 milligrams per liter for total nitrite plus nitrate as nitrogen at well (D-13-14)26bbb exceeded the USEPA's primary maximum contaminant levels of ten milligrams per liter. Lower concentrations of constituents in the ground water indicate that the vadose zone generally attenuates the majority of the contaminants and the level of constituents.
    • Water Quality Assessment of the Santa Cruz River in Southern Arizona

      Rock, Channah M.; McOmber, Todd Christian; Rock, Channah M.; McLain, Jean; Curry, Joan E. (The University of Arizona., 2014)
      Utilization of areas adjacent to rivers for agricultural and industrial purposes can have detrimental effects on water quality and can potentially impact human and ecosystem health downstream. In this study we tested water quality along a stretch of the effluent-dependent Santa Cruz River near Nogales, AZ. This stretch of river has historically been impaired, but prior to upgrades to the Nogales International Wastewater Treatment Plant (NIWTP) in 2009. Our work endeavored to assess water quality according to the Arizona Department of Environmental Quality (ADEQ) standards, and identify sources of pollution entering the river system. Heavy metals were analyzed via ICP. Three IDEXX quantification systems were used to detect E. coli, Enterococcus, and P. aeruginosa as fecal indicators or potential threats to public health. Potential fecal sources were analyzed using quantitative PCR targeting Bacteroides DNA markers for total, human, and bovine feces (Allbac, HF183, and CowM2, respectively). The NIWTP effectively removed chemical and biological contaminants. The lowest E. coli counts occurred at the site located at the NIWTP outfall (mean = 5 MPN/100ml) while the highest counts (mean = 348 MPN/100 ml) came from Nogales Wash, a tributary receiving untreated flow from Nogales, Mexico. The Allbac marker was detected in all samples, while approximately 97% of samples tested positive for HF183 and 33% tested positive for the CowM2 marker. Continued monitoring of effluent effects on river quality and evaluation of water quality degradation will lead to improvements in the management of Arizona's riparian areas and will ultimately contribute to healthy water bodies.
    • Water quality in the lower Colorado river and the effect of reservoirs

      Qashu, Hasan K.; Slawson, Quenton Cyril, Jr.; Qashu, Hasan K. (The University of Arizona., 1972)
      Comparison of the power spectra of TDS time series form different locations on the Lower Colorado River is useful in showing changes in salinity and for indicating physical factors influencing salinity. Similarities between the power spectra of the Lee Ferry and Grand Canyon time series indicated that lateral inputs and evaporation are not greatly influencing the salinity cycle. The salinity change within this reach was approximated by a constant concentration change of 66.6 ppm. A similar model form was used for the Hoover Dam to Parker Dam reach. Dissimilarities between power spectra indicated that additional inputs are significant and must be accounted for in any model of such reaches. The model for Lake Mead required compensation for evaporation and for the inputs of the Virgin River and Las Vegas Wash. The modeled salinity increase between Parker Dam and Yuma contained a trend factor to allow for the effect of irrigation return flows and seepage. The crosscovariance function was used to approximate the time lag between data stations. Time series statistics, including coherence, response function spectra, and over all unit response, were used and are of utility in estimating salinity in a river system.
    • Water quality in the lower Colorado River and the effect of reservoirs,

      Slawson, G. C.; Qashu, Hasan K. (The University of Arizona., 1972)
      Comparison of the power spectra of TDS time series form different locations on the Lower Colorado River is useful in showing changes in salinity and for indicating physical factors influencing salinity. Similarities between the power spectra of the Lee Ferry and Grand Canyon time series indicated that lateral inputs and evaporation are not greatly influencing the salinity cycle. The salinity change within this reach was approximated by a constant concentration change of 66.6 ppm. A similar model form was used for the Hoover Dam to Parker Dam reach. Dissimilarities between power spectra indicated that additional inputs are significant and must be accounted for in any model of such reaches. The model for Lake Mead required compensation for evaporation and for the inputs of the Virgin River and Las Vegas Wash. The modeled salinity increase between Parker Dam and Yuma contained a trend factor to allow for the effect of irrigation return flows and seepage. The crosscovariance function was used to approximate the time lag between data stations. Time series statistics, including coherence, response function spectra, and overall unit response, were used and are of utility in estimating salinity in a river system.
    • A Water quality investigation of Upper Tonto Creek, Gila County, Arizona.

      Dreher, Alan Laird.; Fogel, Martin M.; Thames, John L.; Lehman, Gordon S. (The University of Arizona., 1978)
      The rapidly increasing pressure of recreational activities in Arizona's wildland has the potential for serious environmental impacts on upland watersheds. The greatest hazard from these activities appears to be the possible degradation of natural water quality of mountain streams. The monitoring of surface water quality in areas of heavy recreational use can provide a useful tool for assessing the extent of any impacts, both present and future, which may result from these activities. The upper Tonto Creek watershed was selected as a study area for the establishment of a sampling program to assess baseline water quality conditions and delineate impacts resulting from multiple land use. Results of this study indicate the waters of Tonto Creek are of good quality and have not been seriously degraded at the present time. However, subtle variations in stream water chemistry noted during the study may reflect a weak source of pollution is present in the watershed. A more extensive sampling program would be necessary to pinpoint the source of any pollution and is recommended. The construction and use of water quality models is technically feasible for areas such as Tonto Creek and their use could significantly enhance management objectives on this and similar areas.
    • Water quality management in the Quinnipiac River Basin, Connecticut

      Buras, Nathan; Andrish, Sean David; Buras, Nathan (The University of Arizona., 1997)
      The Quinnipiac River Basin, located in South-Central Connecticut, flows 38 miles from its headwaters in New Britain and Plainville, Connecticut to its mouth in New Haven Harbor. The basin is heavily developed, with the majority of the land in the basin classified as residential and urban. The five municipal water pollution control facilities and one large privately-owned water pollution control facility operating in the Quinnipiac Basin are responsible for maintaining acceptable levels of water quality in the Quinnipiac River. While the current water quality management practices within the Quinnipiac River basin are capable of meeting the various water quality standards, changes in the water quality management system may require an adjustment or alteration of the current management practices. The focus of this study is the identification of possible improvements to the current water resources management practices in the Quinnipiac Basin and a discussion of the feasibility of the proposed improvements.
    • Water quality of gray water for reuse

      Sun, Gwo-Shing,1959-; Gerba, Charles P.; Berry, James W.; Price, Ralph L. (The University of Arizona., 1986)
      This study was designed to evaluate the safety of gray water for reuse purposes. The physical and chemical quality of treated gray water met water reuse standards set by the State of Arizona for surface irrigation purposes. The number of microorganisms in gray water significantly decreased after biological treatment and sand filtration. However, the number of fecal coliform bacteria in treated gray water was still higher than the standard for reuse as set by the State of Arizona for surface irrigation. This is also true for rain water which was stored in a tank. No indigenous Salmonella were isolated from gray water. It was found that both Salmonella typhimurium and Shigella dysenteriae, seeded into gray water, can persist for at least several days. This implied that there may be some risk associated with gray water reuse when the gray water contains these pathogenic bacteria.
    • Water quality of open pit Lake Cospuden status and modeling approaches

      Bassett, R. L.; Muller, Mike; Bassett, R. L. (The University of Arizona., 1997)
      Lake Cospuden is an open pit lake in the mining region of Middle Germany south of the city of Leipzig. The lake which will be used for recreation is filling with recovering groundwater, surface water, and groundwater pumped form the neighboring Zwenkau mine, and is projected to reach its final water level by 2000. The physical limnology of Lake Cospuden is changing during the filling period from an unstratified to a stratified lake with a hypolimnion that is approximately twice as large as the epilimnion. The water quality is typical for a mining lake with low pH and high metal concentration. Due to the filling with neutral surface water, recovery of the initially low pH lake water can be observed. The microbiological environment is attenuated by relatively high phosphorus and nitrogen concentrations, but low chlorophyll-a concentrations, which might be attributed to carbon limitation of photosynthesis due to the low pH. After a rev1ew of general lake models, two models COLQUAL and AQUAMODl, were chosen to simulated the eutrophication process. COLQUAL indicated phosphorus and light as the limiting factors. AQUAMODl, which was modified to incorporate carbon limited photosynthesis, indicated that the eutrophication process is governed by carbon limitation and a mechanism that keeps the soluble reactive phosphorus concentration low, despite of high total phosphorus concentrations. This mechanism was assumed to be related to binding of phosphorus by suspended matter (e.g. clays) which creates turbidity observed in the lake. This study has a preliminary character and identifies future research. Because of its mining history, Lake Cospuden is a unique system and will require alternative approaches in order to evaluate and predict the water quality. Some first steps were attempted in this study.
    • The water quality of streamflow from ponderosa pine forests on sedimentary soils

      Gregory, Paul Wayne,1946-; Ffolliott, Peter F. (The University of Arizona., 1976)
      The primary objectives of this study were to characterize the chemical, physical and bacteriological quality of streamflow from ponderosa pine watersheds on sedimentary soil. The following relationships were statistically evaluated: (1) equality of mean water quality characteristics among watersheds and years; (2) correlation of discharge versus individual variable concentrations; (3) correlation of pH versus individual variable concentrations; (4) correlation of suspended sediment concentrations versus dissolved chemical concentrations; and (5) correlation of electrical conductivity versus total soluble salt concentrations. There was no significant difference in the mean variable concentrations among the watersheds. Therefore, differences in land use patterns and physical characteristics of the watersheds were insignificant regarding effects on average water quality. The mean concentrations from year to year were significantly different, particularly for the year 1973-74. The 1973-74 samples were all taken during the falling stage of streamflow, which could account for the yearly difference. Comparisons of water quality of ponderosa pine watersheds on sedimentary soils to EPA proposed criteria and to water quality of ponderosa pine watersheds on basalt soils were also made.
    • Water quality, storm flow, and wadi fan geology in the lower Semail drainage basin, Sultanate of Oman

      Anderson, Charles Kenneth.; Simpson, Eugene S.; Wilson, Gray; Ince, Simon (The University of Arizona., 1985)
      Wadi fan geology, water quality, and storm flow of the Semail Coastal Plain in Oman were examined. Pliocene—Quaternary-age fan deposits, dune sands, and sebkha deposits characterize the plain. The unconfined coastal aquifer consists of sand, gravel, clay, and cemented gravel. Resistivity, temperature, and caliper logs helped locate production zones. Native and coastal ground water differ in chloride and magnesium concentrations. Chemical analyses indicate four sources of water to the basin. Electrical conductivity and chloride values are lower near active wadi channels. Electrical conductivity profiles indicate that sea water underlies part of the fan deposits. No significant deterioration in water quality between 1978-1982 was noted. Wadi Semail acts as a line source with constricted lateral flow near the fan head and as a radiating line source below mid-fan. A pronounced recharge mound existed in 1982 as a result of storm flow. A diversion structure would increase recharge.
    • Water relations of Vitis vinifera L. c.v. 'Cabernet Sauvignon'

      Pellegrino, Antonio,1959-; Moon, John W. (The University of Arizona., 1987)
      Evapotranspiration measured from two Vitis vinifera L. c.v. 'Cabernet Sauvignon' by the water budget method totaled 136.1 1 d⁻¹, and steady state leaf transpiration rates averaged 57 ± 47 mg m⁻² s⁻¹ from March to August 1986 in Oracle, Arizona. Rooted cuttings were subjected to four levels of water stress in the greenhouse by withholding water. Pot weight variation was correlated to soil water potential by thermocouple psychrometry. Mesophyll conductance and CO₂ assimilation, measured with an open gas exchange system, were decreased by 80 and 70%, respectively, indicating severe limitations imposed by water stress on photosynthesis for this cultivar.
    • Water requirements of urban plants

      Desai, Jayant Bhasker (The University of Arizona., 1981)
    • Water requirements of urban plants

      Desai, Jayant Bhasker.; Fangmeier, Delmar D. (The University of Arizona., 1981)
      Sixteen species of trees, shrubs and ground covers, commonly used in landscape designs in southern Arizona, were given high, medium, and low water treatments under trickle and spray irrigation systems. Annual water deliveries for these plant species were obtained. Well-distributed summer rains substantially reduced the irrigation needs of these plants, and all the plant species were reasonably maintained under trickle irrigation, with less than one-gallon-per-day water deliveries, except Mulberry. Plants were grouped into four categories according to their annual water deliveries, viz., very high, high, medium, and low water users. Trickle-irrigated plants made almost equal growth and maintained similar appearance as spray-irrigated plants, which were given more water. The data on plant growth increments were analyzed for selected ten plant species to determine the effects of reduced water treatments. None of the plant species showed significant linear or quadratic relationships with water levels except Privet, which showed significant linear relationship with high, medium, and low water treatments for plant height and plant spread.
    • WATER RESOURCE ADMINISTRATION OF LOWER CIENEGA CREEK NEAR TUCSON

      Davis, Donald R.; Matt, Clayton Edward (The University of Arizona., 1995)
      The goal of this thesis is to propose water resource management recommenda tions which can contribute to the long-term existence of the lower Cienega Creek riparian area. The objectives are to develop an understanding of the physical, legal, and institutional settings, and to show how those factors have contributed to its current condition. Recommendations are based on a long-term management goal to maintain the riparian area. Potential threats and impacts which would cause severe damage to the area are described. The research includes a combination of a literature search, a water resource and water rights data and records review and analysis, and personal interviews and historical research. The thesis concludes that the Cienega Creek watershed is relatively undeveloped with regard to water consumption. The current condition of the riparian area can be attributed principally to entrenchment and climate change and variation. However, groundwater use looms as a threat to the riparian area. Water management decisions that allow unregulated groundwater development and a high zoning density standard could combine to deplete water resources of the lower Cienega Creek riparian area.
    • Water resources of lower Sycamore Creek, Maricopa County, Arizona.

      Schumann, Herbert H.; Ehrenreich, John H. (The University of Arizona., 1967)
      Like many small watersheds in the Southwest, streamfiow originating in the upper mountainous part of the Sycamore Creek watershed disappears quickly into the alluvial deposits adjacent to the mountains. Streamflow from the upper 165 square miles of the watershed ranged from 167 to 14, 320 acre-feet per water year and averaged 6, 110 acre-feet per water year for the existing 5 years of record. Streamflow measurements indicate that most of the water that enters the lower portion of the watershed does not reach the Verde River as surface flow. On an annual basis from 0 to 10 percent of the streamflow entering the area is subsequently discharged to the Verde River as streamflow. Most of the streamfiow that disappears in the lower area rapidly percolates down to the water table and recharges the groundwater reservoir. Most of this water is released as ground-water discharge at a relatively constant rate of about 4, 000 acre-feet per year to the Verde River. Water losses to evapotranspiration by phreatophytic riparian vegetation in the lower Sycamore Creek area are controlled by the depth to the water table. Annual water losses ranged from as little as about 0. 1 acre-feet per acre during a very dry year to as much as about 3. 1 acre-feet per acre during a very wet year based on a water-budget analysis of these periods. The average annual water loss from the lower area was about 1. 1 acre-feet per acre based on a water-budget analysis of the entire 5-year period of record.
    • The water soluble polysaccharide of Douglas fir, Pseudotsuga taxifolia

      Roebuck, Albert Henry,1922- (The University of Arizona., 1947)
    • Water status determination by sensing stem diameter in cotton plants

      Diaz-Munoz, Fidel (The University of Arizona., 1981)
    • Water stress-induced osmotic adjustment in expanding leaves of tepary bean (Phaseolus actifolius Gray) seedlings

      Akel, Saleh Ali Al-, 1963- (The University of Arizona., 1990)
      Tepary (Phaseolus actifolius Gray) beans perform better than common beans (Phaseolus vulgaris) under drought conditions. The mechanism of drought tolerance in tepary bean seedlings was explored by determining the water potential (WP), osmotic potential (OP), relative water content (RWC), free sugar concentration, and the level of K ion within the expanding leaves. Two week old tepary bean seedlings were subjected to a gradual water stress with sorbitol solutions exhibiting OP values of -0.19 MPa and -0.47 MPa. Turgor remained constant whereas WP, OP and RWC declined following the stress treatment. Osmotic adjustment (OA) occurred in each treatment but the contribution of sucrose and fructose was minor. Some sorbitol was translocated to leaves and contributed to OA. The decrease of K ions in leaves indicated that these ions did not contribute to the OA. A significant decrease in cell size was observed as determined by decrease in TW/DW ratio.
    • Water table response to barometric pressure changes : a laboratory investigation.

      White, Robert R.(Robert Rankin),1942-; Simpson, Eugene S. (The University of Arizona., 1971)
      The water level in water-table wells and in evapotranspirometers has been observed to fluctuate in response to barometric pressure changes. It has been suggested that air bubbles entrapped in the porous media cause the water level changes. It was to test that hypothesis that this study was undertaken. Previous studies of barometric effects are reviewed. Possible sources and consequences of gas in aquifers are discussed. Experiments using gamma-attenuation equipment are described which allow measurement of the amount of air contained in a sample of water-saturated sand at different pressure levels. The theory and practice of gamma-attenuation measurements and the applicability of this method to hydrologic studies are explained. The experimental results demonstrate that air bubbles in the water-saturated sand do change in size in response to pressure changes and that this size change accounts in large part for water level changes. However, an exact correlation between air content and water level was not found, due in part to the difficulty in measuring the small changes which occur. Additional mechanisms which may cause water-level fluctuations are suggested.