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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.
531

Local resolution for watershed management : the case of water and land allocation of Cotacachi, Ecuador /

Rodriguez, Fabián Francisco, January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Includes abstract and vita. Includes bibliographical references (leaves 130-139). Also available via the Internet.
532

Water allocation and development in Wisconsin

Schmid, A. Allan January 1959 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. Abstracted in Dissertation abstracts, v. 20 (1959) no. 3, p. 910. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 307-315).
533

Modelling of power plant cooling water discharges into Lake Monona

Niemeyer, John Allen, January 1969 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
534

New energy geographies : powershed politics and hydropower decision making in Yunnan, China /

Magee, Darrin L. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (p. 302-334).
535

San Francisco-Hetch Hetchy Valley connection /

Davies, Leslie T. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 65-67). Also available via Humboldt Digital Scholar.
536

Communicating risk to an at-risk population concerning future water shortages : focusing on senders and receivers of low-key warning messages in South-Central Texas /

Bartell, Karen H. January 1900 (has links)
Thesis (Ph. D.)--Texas State University-San Marcos, 2007. / Vita. Appendices: leaves 241-521. Includes bibliographical references (leaves 233-240).
537

Model development for seasonal forecasting of hydro lake inflows in the Upper Waitaki Basin, New Zealand /

Purdie, Jennifer. January 2005 (has links)
Thesis (Ph.D. Earth Sciences)--University of Waikato, 2005. / Includes bibliographical references (p. 232-246) Also available via the World Wide Web.
538

Multi-criteria decision-making for water resource management in the Berg Water Management Area /

De Lange, Willem J. January 2006 (has links)
Dissertation (PhD)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.
539

Modelo conceitual de circulação de água subterrânea em aquífero cristalino no município de Itu/SP /

Engelbrecht, Bruno Zanon. January 2017 (has links)
Orientador: Chang Hung Kiang / Banca: Flávio de Paula e Silva / Banca: Emílio Carlos Prandi / Resumo: O sistema aquífero cristalino estende-se por cerca de 62.000 km² no estado de São Paulo, correpondendo a aproximadamente 25% de sua área. A prospecção desses aquíferos, contudo, baseia-se majoritariamente na delimitação de feições lineares nas unidades geológicas e sua correlação com a evolução tectônica regional. Modelos hidrogeológicos conceituais proporcionam a compreensão dos mecanismos que governam a circulação e o armazenamento de água em subsuperfície, permitindo aprimorar e subsidiar a prospecção e gestão dos recursos hídricos subterrâneos. Com este objetivo, o presente estudo apresenta um modelo hidrogeológico conceitual do aquífero cristalino no município de Itu (SP), fundamentado em levantamentos por imageamento elétrico e valores de permeabilidade da zona não-saturada, bem como em análises químicas e isotópicas, tendo como principal enfoque a porção rasa do aquífero e suas interações com as águas superficiais. O modelo embute a ocorrência do manto de alteração e as descontinuidades do maciço rochoso na avaliação do potencial hídrico, prevendo expressiva conectividade hidráulica entre os compartimentos hidráulicos do manto de alteração e do embasamento cristalino fraturado. Os resultados obtidos mostram que a presença de depósitos sedimentares recentes e a ação de processos intempéricos, que resultam em horizontes porosos e na abertura de estruturas preexistentes, favorecem a infiltração, ocorrência e circulação de água em subsuperfície. As características mineraló... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In São Paulo state the crystalline aquifer system occupies about 62,000 km², corresponding to approximately 25% of its area. However, the prospection of these aquifers is based on the delimitation of linear features in the geological units and their correlation with the regional tectonic evolution. Conceptual hydrogeological models provide an understanding of the mechanisms that govern the circulation and storage of groundwater, allowing to improve and subsidize the exploration and management of groundwater resources. For this purpose, this study presents a conceptual hydrogeological model of the crystalline aquifer in the city of Itu (SP), based on electrical imaging surveys and permeability values of the unsaturated zone, as well as chemical and isotopic analyzes focused on the shallow portion of the aquifer and its interactions with surface water. The hydrogeological model incorporates the occurrence of the weathered zone and the discontinuities of the rock mass in the evaluation of the hydraulic potential, predicting expressive hydraulic connectivity between the hydraulic compartments of the alteration mantle and the fractured crystalline basement. The results show that the presence of recent sedimentary deposits and the processes, which result in porous horizons and the opening of preexisting structures, favor the infiltration, occurrence and circulation of subsurface water. The mineralogical and geometric characteristics of the weathered zone, its extension and regional... (Complete abstract click electronic access below) / Mestre
540

THE CHOICE OF WATER SUPPLY SOURCES FOR U.S. CITIES

Chowdhury, Farhat Jahan 01 August 2012 (has links)
Municipal governments consider the provision of water supply as an essential service for public health and safety, economic growth, and community well-being. As the demand for water increases with population growth, municipal water sources are approaching their limits and water source expansion is often constrained by the physical and seasonal availability of fresh water, environmental protection policies and other factors. As systems strive to balance supply and demand, it is important to know what choices U. S. cities are making in developing new sources of supply and, in particular, how U.S. environmental policies are influencing the range of water supply alternatives. This research inquiry was constructed based on four hypotheses: 1) development of large surface water impoundments is no longer a preferred choice of a new source, 2) water utilities increasingly are relying on non-conventional sources for augmenting their supplies. 3) environmental statutes act as constraints in developing water sources, and 4) water needs and planning choices vary by geographic region and water system size. Evidence to explore these hypotheses was collected from detailed case studies of the history of source development of ten municipal water systems and an email survey of 189 drinking water systems throughout the U.S. The historical record of these systems was used to identify a pattern of three distinct periods of water source development: i) groundwater regime, ii) surface water regime, and iii) non-conventional regime. Source development before the Great Depression (1930s) was identified as the groundwater regime. The surface water regime began with the addition of large number of reservoirs that were added as part of the public works programs instituted after the Great Depression. Surface water source development slowed after the 1970s due to the enactment of environmental statutes and the non-conventional regime began. The nationwide water utility survey showed that about 88 percent of respondents reduced their per capita water use since the institution of national plumbing standards in the 1990s. The research also found that development of large surface water impoundments is no longer a preferred choice for cities or municipalities and that "non-conventional" water sources, such as water reclamation and desalination and reclamation began to be employed as alternative sources in 1980s. Environmental statutes such as, National Environmental Policy Act, Clean Water Act (CWA), Safe Drinking Water Act (SDWA), Endangered Species Act (ESA), Rivers and Harbors Act (RHA), and Wild and Scenic Rivers Act (WRSA) have been criticized as constraints to the development of new water sources. However, this research shows that water utilities in general perceive that these statutes are not a constraint. Only 24 percent of respondents perceived them as a constraint and some respondents actually perceived these statutes as an enabler to sustainable water source development. In general, the ESA, CWA 404 permit and NPDES permits were reported to be barriers to water source development, while the SDWA was most reported as an enabler. The research also found that water supply needs and planning choices vary by geographic region. Water systems in the West were more likely to be in need of water source expansion than systems in the East. When considering supply expansions, eastern cities are more likely to pursue conventional sources whereas western cities more likely to pursue a combination of conventional and non-conventional. The water utility survey and case studies showed that while U.S. water systems have employed water demand management techniques to make dramatic reductions in their per capita water use, they nonetheless continue to pursue new water supply sources to meet anticipated future water demands. In spite of this trend toward capacity expansion, virtually all the ten case study water systems currently have surplus water with their current supply exceeding their water demand.

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