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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.
31

RESTORING THE WATER QUALITY OF THE SAN PEDRO RIVER WATERSHED

Klotz, Jason, Tecle, Aregai 18 April 2015 (has links)
This paper is concerned with restoring the quality of water in some portions of the San Pedro River. There are high concentrations of bacteria in some parts of the San Pedro River. Our aim is to find ways of improving the situation. Specifically, there are two objectives in the study. The first one attempts to identify the possible sources of the bacterial contamination and assess its trends within the watershed. The second objective is to determine appropriate methods of restoring the water quality. The main water quality problem is nonpoint source pollution, which enters the stream and moves along with it. The magnitude of the problem is affected by the size and duration of the streamflow, which brings bacteria-laden sediment. The amount of sediment brought into the system is large during the monsoonal events. At this time, the streamflow becomes highly turbid in response to the organic and inorganic sediments entering the system. Based on research done for this paper, the amount of bacterial concentration is strongly related to turbidity. Best management practices (BMPs) have been designed and implemented to restore the water quality problem in the area. The BMP's consist of actions such as monitoring, educational outreach, proper signage, and other range/watershed related improvement practices. Other issues that contribute to the increasing amount of bacteria that are briefly addressed in this paper are bank and gully erosion, flood control, and surface water and streamflow issues that occur on the stream headwaters.
32

RESTORATION OF THE LAS VEGAS WASH AND ASSOCIATED WETLANDS IN LAS VEGAS, NEVADA

Burke, Megan 18 April 2015 (has links)
This paper evaluates the historical growth of the Las Vegas Wash, its subsequent degradation, and the current efforts to restore and stabilize its channel. The Las Vegas Valley Metropolitan Area is located in the Mohave Desert in a drainage basin surrounded by mountain ranges. This drainage basin and its dynamic system of stream channels constitute the Las Vegas Watershed in which the Wash is located. The condition of the Las Vegas Wash is unique, as is a perennial stream that evolved from an ephemeral wash in response to the rapid urbanization and subsequent production of treated wastewater input into the stream channel. The situation has created a series of wetland ecosystems along the Wash, and valuable riparian habitat in such an arid environment. The Wash and its associated wetlands system provide a variety of ecological services to the city of Las Vegas, including storm water conveyance, wastewater effluent filtration, flood protection, and a green space for residents to enjoy. However, continuous increase in volume and intensity of the stream flow has resulted in severe channel degradation and bank erosion in numerous locations along the stream channel. After an examination of the historic and present-day conditions of the Wash and its restoration activities, this essay suggests that future evaluations of the Las Vegas Wash case study may provide evidence to support the propagation of collaborative management efforts.
33

DETERMINING SUCCESS IN WATERSHED RESTORATION USING INTERDISCIPLINARY METRICS: RIO SALADO ENVIRONMENTAL RESTORATION PROJECT, PHOENIX, ARIZONA

Schmidt, Carly H. 18 April 2015 (has links)
Ecological restoration has yet to gain an indepth understanding of the social dynamics that inform restoration design and enable improved watershed performance in urban environments. The Rio Salado Environmental Restoration Project is unique in that the scale of the project expands to new reaches of the Salt River with each successful venture. The 40-year project has been most successful in recent years due to innovative strategies that capitalize on public outreach and inclusion. Adoption of multi-purpose objectives that include partnerships, public stakeholders, and learning achievement have contributed to the project's success. The ability of the restored system to withstand flood events is one of the many examples demonstrating the project's qualifications as a model for future urban restoration efforts. Lessons about the social dynamics that inform urban restoration success have the potential to augment scientific learning in ecological restoration.
34

Hydrology and Water Resources in Arizona and the Southwest, Volume 44 (2015)

18 April 2015 (has links)
No description available.
35

Hydrology and Water Resources in Arizona and the Southwest, Volume 1 (1971)

23 April 1971 (has links)
Complete issue of the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona
36

Hydrology and Water Resources in Arizona and the Southwest, Volume 2 (1972)

06 May 1972 (has links)
Complete issue of the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona
37

Stationarity in Thunderstorm Rainfall in the Southwest

Mills, William C., Osborn, Herbert S. 05 May 1973 (has links)
From the Proceedings of the 1973 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 4-5, 1973, Tucson, Arizona
38

Invited Topical Speaker: E. P. Patten, Simulation of Ground Water Systems with Analog Models (Abstract)

Patten, E. P. 05 May 1973 (has links)
From the Proceedings of the 1973 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 4-5, 1973, Tucson, Arizona
39

Land Treatment for Urban Waste Water Management

Lorah, William L., Wright, Kenneth R. 05 May 1973 (has links)
From the Proceedings of the 1973 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 4-5, 1973, Tucson, Arizona
40

A Public Weighting of Four Societal Goals in Arizona and Oregon

Kimball, D. B., Gum, R. L., Roefs, T. G. 05 May 1973 (has links)
From the Proceedings of the 1973 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 4-5, 1973, Tucson, Arizona

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