Matching Items (4)
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- All Subjects: Water resources development
- All Subjects: Phoenix (Ariz.)
Description
As urban populations grow, water managers are becoming increasingly concerned about water scarcity. Water managers once relied on developing new sources of water supply to manage scarcity but economically feasible sources of unclaimed water are now rare, leading to an increased interest in demand side management. Water managers in Las Vegas, Nevada have developed innovative demand side management strategies due to the cities rapid urbanization and limited water supply. Three questions are addressed. First, in the developed areas of the Las Vegas Valley Water District service areas, how did vegetation area change? To quantify changes in vegetation area, the Matched Filter Vegetation Index (MFVI) is developed from Mixture Tuned Match Filtering estimates of vegetation area calibrated against vegetation area estimates from high-resolution aerial photography. In the established city core, there was a small but significant decline in vegetation area. Second, how much of the observed decline in per capita consumption can be explained by Las Vegas land cover and physical infrastructure change that resulted from extensive new construction and new use of water conserving technology, and how much can be attributed to water conservation policy choices? A regression analysis is performed, followed by an analysis of three counter-factual scenarios to decompose reductions in household water into its constituent parts. The largest citywide drivers of change in water consumption were increased water efficiency associated with new construction and rapid population growth. In the established urban core, the most significant driver was declining vegetation area. Third, water savings generated by a conservation program that provides incentives for homeowners to convert grass into desert landscaping are estimated. In the city core, 82 gallons of water are saved in June for each square meter of landscape converted in the first year after conversion, but the savings attenuate to 33 gallons per meter converted as the landscape ages. Voluntary landscape conversion programs can generate substantial water savings. The most significant result is that the most effective way to ensure long term, sustainable reductions in water consumption in a growing city without changing water prices is to support the construction of water efficient infrastructure.
ContributorsBrelsford, Christina M (Author) / Abbott, Joshua K (Thesis advisor) / York, Abigail M (Thesis advisor) / Hanemann, W. Michael (Committee member) / McPherson, Timothy (Committee member) / Arizona State University (Publisher)
Created2014
Description
ABSTRACT Water resources in many parts of the world are subject to increasing stress because of (a) the growth in demand caused by population increase and economic development, (b) threats to supply caused by climate and land cover change, and (c) a heightened awareness of the importance of maintaining water supplies to other parts of the ecosystem. An additional factor is the quality of water management. The United States-Mexican border provides an example of poor water management combined with increasing demand for water resources that are both scarce and uncertain. This dissertation focuses on the problem of water management in the border city of Ciudad Juarez, Chihuahua. The city has attracted foreign investment during the last few decades, largely due to relatively low environmental and labor costs, and to a range of tax incentives and concessions. This has led to economic and population growth, but also to higher demand for public services such as water which leads to congestion and scarcity. In particular, as water resources have become scarce, the cost of water supply has increased. The dissertation analyzes the conditions that allow for the efficient use of water resources at sustainable levels of economic activity--i.e., employment and investment. In particular, it analyzes the water management strategies that lead to an efficient and sustainable use of water when the source of water is either an aquifer, or there is conjunctive use of ground and imported water. The first part of the dissertation constructs a model of the interactive effects of water supply, wage rates, inward migration of labor and inward investment of capital. It shows how growing water scarcity affects population growth through the impact it has on real wage rates, and how this erodes the comparative advantage of Ciudad Juarez--low wages--to the point where foreign investment stops. This reveals the very close connection between water management and the level of economic activity in Ciudad Juarez. The second part of the dissertation examines the effect of sustainable and efficient water management strategies on population and economic activity levels under two different settings. In the first Ciudad Juarez relies exclusively on ground water to meet demand--this reflects the current situation of Ciudad Juarez. In the second Ciudad Juarez is able both to import water and to draw on aquifers to meet demand. This situation is motivated by the fact that Ciudad Juarez is considering importing water from elsewhere to maintain its economic growth and mitigate the overdraft of the Bolson del Hueco aquifer. Both models were calibrated on data for Ciudad Juarez, and then used to run experiments with respect to different environmental and economic conditions, and different water management options. It is shown that for a given set of technological, institutional and environmental conditions, the way water is managed in a desert environment determines the long run equilibrium levels of employment, investment and output. It is also shown that the efficiency of water management is consistent with the sustainability of water use and economic activity. Importing water could allow the economy to operate at higher levels of activity than where it relies solely on local aquifers. However, at some scale, water availability will limit the level of economic activity, and the disposable income of the residents of Ciudad Juarez.
ContributorsGarduno Angeles, Gustavo Leopoldo (Author) / Perrings, Charles (Thesis advisor) / Holway, Jim (Thesis advisor) / Aggarwal, Rimjhim (Committee member) / Arizona State University (Publisher)
Created2011
ContributorsFerrell, Janet (Author) / Spierre, Susan (Author) / Chester, Mikhail Vin (Author) / Arizona State University. School of Sustainable Engineering and the Built Environment (Contributor) / Arizona State University. Center for Earth Systems Engineering and Management (Contributor)
Created2012-05
Description
Better methods are necessary to fully account for anthropogenic impacts on ecosystems and the essential services provided by ecosystems that sustain human life. Current methods for assessing sustainability, such as life cycle assessment (LCA), typically focus on easily quantifiable indicators such as air emissions with no accounting for the essential ecosystem benefits that support human or industrial processes. For this reason, more comprehensive, transparent, and robust methods are necessary for holistic understanding of urban technosphere and ecosphere systems, including their interfaces. Incorporating ecosystem service indicators into LCA is an important step in spanning this knowledge gap.
For urban systems, many built environment processes have been investigated but need to be expanded with life cycle assessment for understanding ecosphere impacts. To pilot these new methods, a material inventory of the building infrastructure of Phoenix, Arizona can be coupled with LCA to gain perspective on the impacts assessment for built structures in Phoenix. This inventory will identify the origins of materials stocks, and the solid and air emissions waste associated with their raw material extraction, processing, and construction and identify key areas of future research necessary to fully account for ecosystem services in urban sustainability assessments. Based on this preliminary study, the ecosystem service impacts of metropolitan Phoenix stretch far beyond the county boundaries. A life cycle accounting of the Phoenix’s embedded building materials will inform policy and decision makers, assist with community education, and inform the urban sustainability community of consequences.
ContributorsFerrell, Janet (Author) / Chester, Mikhail Vin (Author) / Arizona State University. School of Sustainable Engineering and the Built Environment (Contributor) / Arizona State University. Center for Earth Systems Engineering and Management (Contributor)