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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Water Supply Planning for the Bi-National Region of Nogales, Sonora and Arizona

Fogel, Martin, Tecle, Aregai 19 April 1986 (has links)
From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, Arizona
212

Microbial Quality of Gray Water for Reuse

Rose, Joan B., Sun, Gwo-Shing, Weimer, Bart C., Silverman, Rod S., Gerba, Charles P., Sinclair, Norval A. 19 April 1986 (has links)
From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, Arizona / As the scarcity of water and the price of municipal water inevitably increase, gray water reuse may become an inexpensive and viable alternative for such purposes as irrigation, lawn maintenance and water closet flushing. However, some problems do exist. The microbial and chemical content of gray water includes agents that may present public health problems. The purpose of this study was to determine the general microbial composition of gray water using standard plate counts and selective media at specific sites (shower/bath, wash cycle and rinse cycle of a clothes washing machine) and the general chemical and physical properties of gray water at these same sites (phosphate, ammonia, chloride, pH, TDS and turbidity). Samples were taken from a diverse group of families with and without children (1 ½ - 9 years). Standard plate count bacteria ranged from 10⁵ to 10¹⁰ colony forming units (CFU)₄/100 ml. Shower and bath water contained an average of 10⁴ to 10⁶ CFU/100 ml of coliforms. Failies with children produced wash cycle gray water containing 10⁶ CFU /100 ml of fecal coliforms. Ammonia concentrations varied proportionally with bacterial concentrations while phosphate varied inversely with bacterial growth. Bacterial numbers increased one order of magnitude during storage of gray water.
213

Rainfall pH in Tombstone, Arizona, 1968-81

Bohn, Hinrich L., Schreiber, Henry, Cooper, Loel R. 19 April 1986 (has links)
From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, Arizona / Rainfall pH was measured at the Tombstone, Arizona, USDA-ARS station from 1968 to 1981. The summer rains were more acidic than the winter rains. The pH of the summer rains was about pH 5, the winter rains about pH 6, with considerable variation. The summer rain pH increased gradually over this period, coinciding with a general decrease of sulfur emissions from the nearest copper smelter at Douglas, Arizona, and from' all smelters in Arizona. The ionic composition of the rainwater was quantitively uncertain due to numerous changes in analytical procedures. The acidity was very roughly related to sulfur content. The inverse relation between acidity and Ca and Na content was somewhat clearer.
214

Twenty-Five Years of Snow Research in Arizona: A Preliminary Report

Ffolliott, Peter F. 19 April 1986 (has links)
From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, Arizona
215

Residential Water Conservation Progress Report for Casa Del Agua

Foster, Kennith E., Karpiscak, Martin M., DeCook, K. James, Brittain, Richard, Gerba, Charles P., Parton, Michael C., Rawles, R. Leslie 19 April 1986 (has links)
From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, Arizona / Casa del Agua, a research and demonstration water conservation house, was opened to the public in September 1985. This typical 3 bedroom residence has been re-landscaped and retrofitted with storage for rainwater and graywater and low water use plumbing fixtures including toilets. A unique graywater treatment system employs two 300 gallon aquacells and a sand filter to upgrade graywater quality. The house is occupied by a family of three and detailed data are being obtained on water input, use and quality. Qualitative measures include microbiological, physical and chemical characteristics of filtered rainwater and treated, untreated and stored graywater. A model of water efficiency for dwelling units known as the "W-Index" is being formulated as a quantitative measure of residential water conservation options. The numerical evaluation of weighting of the index components will be aided by means of data generated in the monitoring program at Casa del Agua. A nomogram has been developed to provide a ready mechanism to determine the necessary storage volume for rainwater in terms of a specified availability of supply, catchment area, and rate of water use.
216

Streamflow Response to Converting Arizona Chaparral in a Mosaic Pattern

Hibber, A. R., Davis, E. A. 19 April 1986 (has links)
From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, Arizona / Converting 55% of an Arizona chaparral watershed to grass in a mosaic pattern, giving major consideration to wildlife habitat values, water quality, and landscape esthetics, produced an average of 68 mm of extra streamflow per year from the watershed during a 4-year evaluation period. When the increased streamflow was prorated to the area actually treated, the increase amounted to 124 mm. Increases in streamflow were largest in winter, and streamflow was extended considerably longer into the dry periods than before treatment.
217

Seasonal Analysis of Colorado River Flows through the Grand Canyon from 1914-1985

Avery, Charles C., Beus, Stanley S., Carothers, Steven W. 18 April 1987 (has links)
From the Proceedings of the 1987 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 18, 1987, Northern Arizona University, Flagstaff, Arizona / The building of the Colorado River Storage Project dams during the 1956-1976 period obviously altered the natural flow regime of the Colorado River through the Grand Canyon. As desired, the spring snow-melt generated flows were retarded and the annual fluctuations were considerably dampened. This paper presents an analysis of the seasonal flow changes caused by the CRSP structures and highlights some of the characteristics of historic Colorado River flows. It also suggests that a strategy for recreating the pre-dam ecosystem would be to emulate some significant characteristics of the pre-dam flows.
218

Snowpack Density: An Index of Snowpack Condition

Ffolliott, Peter F. 27 April 1985 (has links)
From the Proceedings of the 1985 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 27, 1985, Las Vegas, Nevada
219

Storm Runoff and Sediment Production After Wildfire in Chaparral

Hibbert, Alden R. 27 April 1985 (has links)
From the Proceedings of the 1985 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 27, 1985, Las Vegas, Nevada / Stormflow and sediment production increased greatly after a wildfire on three small cha3parrlal watersheds in .entral Arizona. Peaks frequently exceeded 5 m³ s⁻¹ km⁻² (450 cfg mi⁻²) when 15-minute rainfall intensity exceeded 50 mm hr⁻¹ (2 in hr⁻¹) on catchments that, before burning, responded little to intense rainfall. Source water for the flashy spates and heavy erosion was surface runoff on the severely burned, unprotected, water -repellent soils. For a few years after the fire, intense summer rains produced a disproportionate amount of the runoff and sediment. Early postfire recovery was rapid; severe flooding and erosion were over in 3 years, and within 5 to 10 years stormflows and peaks declined to near prefire levels. Postfire conversion to grass on one watershed did not appreciably change the rate of recovery.
220

Arizona Water Information Center: Foundation and Activities

Foster, Kennith E., Wilson, L. G. 27 April 1985 (has links)
From the Proceedings of the 1985 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 27, 1985, Las Vegas, Nevada

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