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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.
601

Changes in Water Rates and Water Consumption in Tucson, 1974 to 1978

Griffin, Adrian H., Wade, James C., Martin, William E. 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada
602

Socio-Economic Impacts of the Safe Drinking Water Act on Arizona's Water Systems

Williamson, Richard S. 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada
603

Factors to Consider in Drafting Standards to Protect Groundwaters in Arizona

Bennett, Marc M. 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada / A summary of factors which need to be addressed when drafting standards to protect groundwater is presented based on research of existing and proposed groundwater quality standards in several states. Options available for each factor are offered as possible choices.
604

Water Quality Analyses of the Colorado River Corridor of Grand Canyon

Tunnicliff, Brock, Brickler, Stanley K. 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada / Water quality research of the Colorado River corridor of Grand Canyon examines important relationships between densities of fecal coliform bacteria in surface water and underlying bottom sediments. Surface water sampling alone does not accurately reflect baseline water quality status of natural recreational waters, as sediments often harbor microbial densities in several orders of magnitude of overlying waters. Water-based recreation activities and natural wave and current processes can resuspend sediment and associated microbial populations, including enteric pathogens. Data show significant associations between surface water and bottom sediment microbial populations, demonstrating the importance of a combined sampling approach to water quality analyses.
605

Exploration for Saltwater Supply for Shrimp Aquaculture, Puerto Penasco, Sonora, Mexico

DeCook, K. J., Ince, S., Popkin, B. P., Schreiber, J. F., Jr., Sumner, J. S. 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada / The University of Arizona's Environmental Research Laboratory, with the Universidad de Sonora, has operated a research station at Puerto Peñasco, on the northeastern Gulf of California, since 1962. Controlled-environment shrimp aquaculture, the Laboratory's most recent research interest, requires a large, dependable supply of filtered, temperate seawater. A University Water-Supply Study Team explored for a supply in an 850-hectare site near the Estero Marua for a proposed ten-hectare shrimp farm. The study included geological, geophysical, and hydrological investigations, and consideration of groundwater, Gulf, estuarine, and combined seawater sources. A thick, fine sand, in the study area, has a very low permeability, contains highly saline water, and could sustain low yielding wells. A thin, coquinoid beachrock, along the Gulf coast near the study area, has a high permeability, contains seawater, and could sustain high yielding wells. Gulf and estuarine water sources have unacceptable temperature ranges, though they could be utilized if mixed with groundwater, stored, and insulated. Recommendations include: drilling, testing, and analysis of coquina; modeling of groundwater heat flow, water-quality effects, and potential well-field designs and impacts for beachrock development; analyzing well design and performance; relaxing temperature and salinity constraints; reusing aquacultural wastewater; and reducing water demand.
606

Well-Field Design Criteria for Coastal Seawater Development

Popkin, Barney P. 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada / The University of Arizona's Environmental Research Laboratory, with the Universidad de Sonora, has operated a research station at Puerto Peñasco on the northeastern Gulf of California, Sonora, Mexico, since 1962. Research projects have included solar distillation, greenhouse agriculture, shrimp aquaculture, and halophyte irrigation. These require a dependable supply of filtered, temperate seawater. Proposed aquacultural expansion requires a large water supply. The thin, coastal, water-table coquinoid-beachrock aquifer has a high permeability, contains seawater and could sustain high yielding wells from a limited area. Well performance indicators (yield, specific capacity, efficiency and losses) are influenced by design, drilling, development and siting, and aquifer properties and hydrogeologic boundaries. Design should include full aquifer penetration, open -area screens, sized gravel pack and proper pump sutmergence. Drilling should be by mudless reverse circulation. Development should consist of simultaneous air lifting and jetting. Siting should include proximity to the recharging Gulf and adequate well spacing. Total well-field production is controlled by individual and collective well performance, and by regional hydrogeologic conditions.
607

Estimating Transmission Losses in Ephemeral Stream Channels

Lane, Leonard J., Ferreira, Virginia A., Shirley, Edward D. 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada / Procedures have been developed to estimate transmission loss volumes in abstracting (losing) ephemeral streams. A two -parameter linear regression equation relates outflow volume for a channel reach to the volume of inflow. A simplified two-parameter differential equation describes the transmission loss rate as a function of length and width of the wetted channel. Linkage relationships between the regression and differential equation parameters allow parameter (and thus, transmission loss) estimation for channels of arbitrary length and width. The procedure was applied using data from 10 channel reaches. Maximum loss rates were observed on Walnut Gulch, Arizona, and minimum loss rates were observed on Elm Fork of the Trinity River, Texas. All other data were between limits established at these two locations. Examples illustrate typical applications and show step-by-step procedures required to use the proposed method. Results and interpretations were summarized, and needs for additional research were specified.
608

Three-Dimensional Velocity Log in Groundwater

Chagnon, Richard P., Screens, Johnson 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada
609

Application of the USLE to Southwestern Rangelands

Simanton, J. Roger, Osborn, Herbert B., Renard, Kenneth G. 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada
610

Computerized Depth Interval Determination of Groundwater Characteristics from Well Driller Logs

Long, Mike, Erb, Stephen 12 April 1980 (has links)
From the Proceedings of the 1980 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona - Nevada Academy of Science - April 11-12, 1980, Las Vegas, Nevada

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