Dissertations / Theses on the topic 'Conservation of water resources'

Thesis (M.Eng.)(Chemical Engineering)--University of Pretoria, 2006.
Accompanied by a CD-ROM: Appendix B. Cooling tower model results. Includes bibliographical references. Available on the Internet via the World Wide Web.

From the Proceedings of the 1989 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 15, 1989, University of Nevada, Las Vegas, Nevada
A typical single family residence in Tucson, Arizona (Casa del Agua) was retrofitted with water conserving devices, graywater and rainwater recycling systems, and a low water use landscape. An educational tour designed to promote the incorporation of these water saving techniques has been ongoing at the home since December, 1985. A questionnaire survey was administered between April and July 1988 to determine the extent of water conservation behavior, demonstrated by the adoption of the water conservation techniques, of the Pima County population and the tour participants. Both population samples exhibited similar water conservation behaviors. It was also determined, from the analysis of the survey results, that the tour led to additional water conservation technique adoption.

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

From the Proceedings of the 1989 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 15, 1989, University of Nevada, Las Vegas, Nevada
Casa del Agua is a research and demonstration project to test the efficiency and liveability of a house that has been relandscaped and redesigned with water saving and recycling devices. Ongoing research focuses on six interrelated tasks: 1) water quality and sampling to characterize graywater and rainwater and to determine their potential to impact the environment; 2) water balance analysis that quantifies fresh water use, graywater production and use, and rooftop runoff and use; 3) evaluation of system components that could enhance graywater reuse; and 4) maintenance and modification of existing systems. An interpretation of recent data and information derived from the performance of the above tasks indicates the effectiveness of the project's water-saving strategies, as well as other significant findings relevant to water conservation in an urban, residential setting.

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.

From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona
The availability of quality water is an important issue facing the residents of Tucson, Arizona and several communities in the Southwestern United States. As cities continue to grow, more emphasis is being placed on the importance of adopting efficient water use practices and behaviors. A water conservation demonstration, education, and research single family residence named Casa del Agua (Spanish for House of Water) has been established in Tucson, Arizona. Water conservation information is presented to the public via oral and video presentations and a guided tour of the perimeter of the residence. A questionnaire is given to the visitors as they arrive for the tour. The responses to this questionnaire make it possible to determine the types of water conservation behavior being practiced by the visitors to Casa del Agua. Water conservation attitude questions were also included in the questionnaires as were questions about several water issues. From this preliminary study, it has been determined that the levels of adoption of water conservation behaviors have been low to modest. It appears that many of the visitors to Casa del Agua have about the same level of knowledge concerning water conservation as the general public, although the random survey data for the Tucson area has yet to be analyzed. A comparison was made of similar questions asked in a random survey conducted in the Phoenix metropolitan area March 17 -20, 1988. Some of the findings include: 1) The amounts of self- reported water conservation behavior adoption are similar, although the residents of the Phoenix area seem to report a slightly higher percentage of water conservation practices being implemented. 2) Few respondents from either survey indicated they have attended a water conservation demonstration or workshop. 3) Negative public perceptions of water utilities need to be addressed. 4) Water conservation programs that include economic incentives are favored by both survey populations.

Social-ecological systems are facing complex social, political, economic and environmental problems beyond the capacity of one group of stakeholders or organization to solve in isolation. Ecosystem degradation causes major environmental and economic concern, due to the loss of ecosystem services which river and wetland ecosystems provide. Stakeholder communities who depend on natural resources need to identify the social processes which are underlying causes to unsuccessful natural resource management and thus environmental degradation. The study is primarily aimed at identifying and understanding the structural and functional properties of the stakeholder network in the Duiwenhoks River catchment in the Western Cape, South Africa. Through analyzing the social network properties the study identifies and describes the main stakeholders involved with natural resource management in the Duiwenhoks water catchment area. How the individual actors from the diverse stakeholder groups are connected through communication ties were assessed. Furthermore, issues and factors which limit the effectiveness of the social network were identified. The main factors include a lack of communication and collaboration between key local resource users and governance officials caused by conflicting perspectives regarding resource management and societal conflicts caused by asymmetries in power distribution favoring government institutions. The lack of collaboration between stakeholders was identified as a contributing factor that links to the resource degradation experienced in the catchment. Ultimately means of overcoming the limitations to effective social networking, in order to manage the challenges related to natural resource management were identified. Management recommendations include the development of bridging ties and collaboration between diverse stakeholders, whilst facilitating participatory processes aimed at participatory problem solving and adaptive co-management of natural resources. Government institutions were identified as being dominant stakeholders in the network and should be mobilized to perform a stronger bridging role to connect disconnected actors. The findings of the study may inform future efforts of researchers and facilitators to implement strategies which promote social networking, social learning and ultimately adaptive co-management in the study area or other similar social-ecological systems. Ultimately, collaboration can be achieved between the diverse stakeholders to successfully improve ecosystem management and resilience in the Duiwenhoks water catchment.

Water security is becoming an increasing concern for communities in the southwestern United States. Projected decreases in water availability due to climate change combined with increased demands from a rapidly growing population have many concerned about the sustainability of the water supply in coming years. As water availability becomes an increasing concern, greater efficiencies must be made to increase the resilience of the water supply system. This dissertation analyzes the efforts of Tucson, Arizona households to conserve water during the hottest and driest decade in the city's recorded history, between 2000 and 2009. This study utilizes survey data to statistically examine the motivations for household adoption of five conservation methods: rainwater harvesting systems, graywater systems, xeriscaping, high-efficiency devices and volunteerism for public water conservation projects. Following the statistical analysis, interviews were conducted with participants to provide further context for analyzing the results. This mixed method approach reveals that drought alone did little to directly encourage household water conservation over the decade. However, public water conservation initiatives that were launched during the decade made a significant contribution to increasing household water conservation. Households consistently cited a desire for more information about the implications of the current drought status as well as additional information about their individual household's water use.

Thesis (M.S. in Management)--Naval Postgraduate School, December 1990.
Thesis Advisor(s): Moore, Thomas P. Second Reader: Gates, William R. "December 1990." Description based on title screen as viewed on April 2, 2010. DTIC Identifier(s): Water Supplies, Irrigation Systems, Salinas River Valley (California), Theses, Free Market, Water Conservation, Public Policy, Salt Water, Policies, Farm Crops, Marketing. Author(s) subject terms: Groundwater Allocation, Groundwater Markets, Agricultural Groundwater, Salinas River Valley. Includes bibliographical references (p. 90-94). Also available in print.

The purpose of this study was to develop a better understanding of water-conscious residents’ thought processes that may lead to behavioral and attitudinal changes when introduced to information that increased their awareness of the amount of water used by the beef and dairy industry in Arizona. A total liberation framework rooted in critical animal studies provided the theoretical foundation for explaining how speciesism and carnism support the power structures of the animal industrial complex and how cognitive dissonance theory may affect future efforts toward engaging more people in the resistance of this oppressive, violent, and unjust system. Research showed that over 40 percent of Arizona’s fresh water withdrawals are used to grow crops for animal consumption. This information was presented to a focus group consisting of seven participants interested in water conservation and consumed beef every week. A mixed methods approach to analyzing quantitative and qualitative data explored the complex decision-making process that influences an individual’s beliefs and behavioral choices to continue, reduce, or eliminate beef and dairy from their diet. The data resulted in the postulation that introducing water-conscious citizens to the amount of water used by the beef and dairy industry causes cognitive dissonance, encouraging them to reduce their beef and dairy consumption and consider underlying power structures that support animal agribusiness as they reconcile the dissonance between their current behavior to conserve water and their current behavior to consume beef and dairy.

This study is an academic research project completed to satisfy the California Polytechnic Master Thesis Requirement for the Master Degree of City and Regional Planning in the College of Architecture and Environmental Design. The County of San Luis Obispo Planning and Building Department is the client for this professional project. The project was requested by the County of San Luis Obispo to assist in its water conservation efforts and to help achieve a 20 percent per capita reduction of water use by the year 2020. The project consists of two documents: A Handbook of Water Conservation Technologies and Practices (Handbook) and the Background Report for the Water Conservation Handbook (Background Report). The Handbook is intended to provide a quick guide to various water conserving fixtures and appliances that developers and residents throughout the County of San Luis Obispo can reference for personal use. The Handbook includes information on the type of technology, the benefits in terms of water saving potential, and the cost of implementation. The Handbook is organized based on Indoor and Outdoor water uses. The Background Report is a supplemental document for the Handbook which provides more in depth descriptions and examples on each technology. The Background Report also provides history on water conservation issues in California and San Luis Obispo. It looks at two case studies: one, on the water conservation efforts in Phoenix, Arizona, and two, on a plumbing retrofit project on the Cal Poly Campus that was awarded LEED certification for its water savings. Furthermore, the Background Report explores case studies in the use of community participatory planning to produce water conservation plans. The studies focused on a Community Plan development in Arroyo Grande, California, and on an Integrated Regional Water Management Plan in the Greater Los Angeles Region. The Background Report concludes by providing some cautionary advice on water conservation technologies and provides future recommendations for the county of San Luis Obispo to improve its water conservation efforts.

Globally, amphibians have suffered dramatic population declines in the past twenty years with habitat destruction implicated as the primary threat. The Natural Resources Conservation Service’s Wetlands Reserve Program (WRP) restores wetlands on marginal agricultural land and is a means to restore the spatio-temporal wetland habitat required by amphibians to prevent, reverse, or stabilize declining population trends. The goal of WRP is “to achieve the greatest wetland functions and values, along with optimum wildlife habitat, on every acre enrolled in the program.” Functions and values are defined as the hydrological and biological characteristics of wetlands. A key unanswered question is to what extent is this goal being achieved? Amphibians enable quantifying the WRP goal due to their life-history requirements and explicit incorporation of their habitat needs into WRP plans. My research goal was to determine if hydrological and biological wetland characteristics had been restored to WRP sites in the Lower Grand River basin, north-central Missouri, based on distribution, recruitment success, and relative species richness estimates for members of a regional species pool. I identified three design strategies applied to WRP sites over time: walk-away, maximize hydrology, and naturalistic; the latter emphasizing restoring process as well as structure; and evaluated if design strategy was a useful covariate for restoration efforts. I encountered 10 amphibian species representing 59% of the regional species pool. Design strategy was not a predictive site-level covariate as sites within all three design strategies had varying hydrological wetland conditions resulting in greater habitat heterogeneity than anticipated on maximize hydrology and walk-away sites and less than anticipated on naturalistic sites. Amphibian detections occurred across all sites resulting in no difference among design strategy as the degree of heterogeneity in habitat conditions at the within site-scale demonstrated that amphibians were responding to ecological conditions that occur at a finer resolution than site. Results, irrespective of design strategy, indicate seven of the detected species or groups were widely- distributed, two were moderately- distributed, and two were sparsely distributed on WRP sites indicating hydrological wetland characteristics have been restored to sites given the moderate- to wide-distribution of species associated with both seasonal and permanent wetlands. Although species were successfully recruiting young into adult populations, only leopard frogs had high estimates of recruitment success whereas the remaining species had moderately high to moderate to low recruitment estimates indicating biological wetland characteristics are somewhat lacking to lacking for these species. Results from the relative species richness assessment indicate that, whereas 74% of the sites provided some degree of wetland habitat for members of the regional species pool over the course of the field season (7 March – 19 September), 52% of the sites lacked suitable habitat conditions during the peak of amphibian breeding and larval development (May through July). Targeting management actions that result in suitable seasonal wetland habitat conditions (shallow, vegetated wetlands that gradually dry by mid-to late-summer) throughout the time needed for species to complete their life history requirements is one method to increase the biological wetland value of restored WRP sites. Results show the value of WRP at conserving and restoring river-floodplain amphibians; however, achieving optimum wildlife habitat on every enrolled acre will be difficult at a site-level scale as habitat requirements, although overlapping, vary widely for the full range of species. Providing for all species in the regional species pool requires sites that transverse both the longitudinal and lateral floodplain gradient. If WRP is to realize its full potential, there must be recognition that optimum wildlife habitat can be defined at multiple spatial and temporal scales that match the landscape setting. Optimum wildlife habitat at a wetland scale is not the same as optimum wildlife habitat at the floodplain scale. The intent of WRP is to convert marginal, flood-prone agricultural lands back into wetlands so enrollment of lands located outside the active floodplain may be impracticable or unrealistic. Whereas attaining optimum wildlife habitat on every acre enrolled in the program may not be an achievable objective, providing optimum wildlife habitat for members of a regional species pool within an appropriately defined geography that includes both a longitudinal and lateral gradient represents an objective that is both desirable and attainable.

15 pp.
Arizona Watershed Stewardship Guide (10 related modules to be published in combined form)
Arizona Watershed Stewardship Guide was created to help individuals and groups build a mutual foundation of basic knowledge about watersheds in Arizona. It is intended to help Arizonans understand and be good stewards of their watersheds. The guide was designed to compliment the mission of Arizona Master Watershed Steward program to educate and train citizens across the state of Arizona to serve as volunteers in the restoration, conservation, monitoring, and protection of their water and watersheds. The guide consists of 10 self-contained modules which teach about important aspects of watershed science and management.

Revised; Originally Published: 2008
6 pp.
Climate change is affecting Arizona's Water Resources adversely and water use is linked to energy consumption. This publication discusses the effects of global warming on the environment and provides tips on how to conserve electricity at home.

This study uses the double-bounded bid elicitation format to estimate how much households in the Khalong-la-Lithunya wetland area (KWA) would be WTP (on top of monthly water bills) for wetland resource conservation, and test whether WTP significantly varies with the institution responsible for its conservation management. KWA was purposely selected on account of the critically important role it plays in securing water provisioning ecosystem services; a role that is currently threatened by proximate and ultimate factors hypothesised to be driven by its unrecognised economic value. WTP was thus elicited and compared when the governance institution was (i) the Ministry of Natural Resources, and (ii) a private environmental conservation agency that is currently active in Lesotho i.e. the Transformation Resource Centre (TRC). Purposive and simple random sampling methods were used to collect survey data from 204 households. Results show that respondents have high levels of factual knowledge about the threats to the sustainability of KWA. They also have attitudes, opinions, and perceptions that are receptive to a policy that improves the status quo. Mean WTP was M78.80 per household per month (UB M92.89 and LB M38.21) when the Ministry of Natural Resources was responsible for conservation management in KWA (equivalent to M 0.011 per litre or M0.21 per 20 litre jerry can), and M83.09 per household per month (UB M98.00 and LB M32.94) when TRC was responsible for conservation management in KWA (equivalent to M0.011 per litre or M0.22 per 20 litre jerry can). The null hypothesis of equality of the two mean WTP values was rejected at the 1 % level (t= 4.34 and p = 0.000), suggesting that institution responsible for conservation management in KWA significantly influences households' WTP. Double bounded models differentiated by institution responsible for conservation management in KWA were used to econometrically determine factors that influence households' WTP. Results show that WTP was positively related to the following variables: income, age, education, whether households had experienced seasonal water shortages, knowledge of health risks associated with water shortages, and gender (males had higher WTP). WTP was found to be negatively related to household size (the more the household members, the lower the WTP). These results were consistent with prior expectation and literature. Considering, also, that this study further used secondary sources to estimate that households, on average, spend about M300 per month on water (equivalent to M0.04 per litre or 0.80 per 20 litre jerry can), three key recommendations follow. First, subject to extensive stakeholder consultations, the Water and Sewerage Authority (WASA) of Lesotho should consider adding to the regular charge a resource conservation tax amounting to at least M0.011 per litre of water delivered to customers, i.e. instead of charging M0.04 per litre of water delivered, WASA should charge customers at least M0.051 per litre of water delivered. Second, WASA should consider instituting a policy that isolates the conservation charge from the M0.51 per litre, and explicitly invest it in mitigating the resource conservation challenges in KWA (i.e. the charge should be used to support activities that secure the sustainable water provisioning ecosystem services from KWA). Finally, WASA should consider engaging TRC directly in converting the proceeds from the conservation charge to tangible resource conservation outcomes in KWA, given that households expressed higher WTP when TRC was responsible for its conservation management.
Dissertation (MSc (Agric))--University of Pretoria, 2017.
Agricultural Economics, Extension and Rural Development
MSc (Agric)
Unrestricted

The Asian clam, Corbicula fluminea, is one of the most invasive bivalves in the world but there is limited research on its presence in tidal freshwater systems. Despite its introduction into Chesapeake Bay tributaries in the 1970s, the initial colonization and subsequent development of populations of C. fluminea in the Mattaponi and Pamunkey sub-tributaries of the York River, Virginia, is mostly undocumented. This study assessed the spatial distribution and population structure of C. fluminea in tidal freshwater sections of these rivers (~45km) with benthic surveys during summer 2011 – 2012. Benthic grabs (2.4L, 0.023m2) taken at 40 sites in each river were analyzed for clam abundance and size. In addition, relationships between abiotic factors and clam distribution within each river were evaluated using Akaike’s Information Criterion (AIC) to compare a set of generalized linear models. C. fluminea was present at the majority of sites in both rivers during both years, with mean densities (m-2) during 2011 and 2012 of 660 and 410 for Mattaponi River; 1,451 and 834 for Pamunkey River. Populations were dominated by > 90% juvenile clams (< 6mm shell length), which is common for C. fluminea populations during recruitment periods. Both rivers had lower abundance during 2012, suggesting that C. fluminea is actively reproducing but not necessarily accumulating in the system. High juvenile and adult mortality are characteristic of C. fluminea populations. Compared to other invaded systems, C. fluminea in Mattaponi and Pamunkey Rivers is a low-to-moderate level invasion based on clam density. Using AIC analysis, the bestsupported models included factors of distance upriver (km), % sand, depth (m), and year. Distance and % sand showed positive relationships with C. fluminea abundance and had significant parameter estimates in all models (" = 0.05). Spatial analysis in GIS showed 3 that C. fluminea was widely distributed throughout the rivers but achieved higher densities further upriver and in sandier habitats. Despite these trends, Corbicula densities were highly variable, highlighting eurytopic habitat preferences of this species that have led to its successful invasion of tidal freshwater habitats. Populations may also be controlled by the high degree of physical disturbance in tidal freshwater systems and predation by fish and waterfowl.

Rivers are vital for sustaining biodiversity and human development, yet globally only a small fraction of rivers enjoy protection and those with protections are often impaired or modified. Rapid rates of freshwater species’ extinctions indicate current conservation practices are failing. Despite over fifty years of scientific evidence justifying river conservation, it remains that less attention is focused on protecting ecosystems than on developing water resources for economic growth. This disparity is indicative of the ‘nature as resource’ versus ‘conservation of nature’ paradigm. Today, this paradigm is complicated by new attentions centering both on water resource development projects and conservation policy as climate change adaptation strategies. Policies protecting rivers are recommended for contending with more intense storms and flooding, increasing resilience for species, forests, and agricultural areas, and fostering some types of water security. Creating, implementing, and managing climate adaptation policies will require a strong state presence in water resource governance. We know, however, the aforementioned paradigm hinders conservation policymaking. Therefore, understanding how conservation policy has already been rationalized, implemented, and managed is critical to advancing climate adaptation policymaking. Yet, little empirical research has been conducted on federal river conservation policy creation or application across the U.S. To that end, this dissertation, presented in three discrete original research articles, examines the United States National Wild and Scenic Rivers System. Specifically, this study investigates the socio-ecological drivers behind the creation of the Wild and Scenic Rivers Act of 1968 (WSRA hereinafter) and the spatial dimensions of the policy’s application and management over time. This study is grounded empirically in extensive archival materials, interviews with federal land management agency personnel, conservation advocates, and technical experts, as well as spatial and temporal analysis of a geodatabase. Together, these methods were employed to answer the following research questions which guide this study: (1) What factors influence the temporal and spatial distribution of river segments protected under the Wild & Scenic Rivers Act? (2) What does the history of management in designated segments suggest about emerging trends and patterns in river conservation? (3) How are competing environmental values and ideologies understood and reconciled in the context of river conservation?

Thesis (MScEng (Civil Engineering))- -University of Stellenbosch, 2011
ENGLISH ABSTRACT: The limited water supply and an increasing water demand means that the effective management of water resources becomes much more important than in the past. The implementation of water demand management / water conservation (WDM/WC) projects are usually used as a crisis management tool to reduce immediate water shortage and to allow time for the planning and construction of infrastructure to increase water supply. It is however possible to incorporate WDM/WC into integrated water resource management and to use WDM/WC as an economic viable option for the upgrade of infrastructure to balance supply and demand. Existing economic evaluation methods to compare different options with each other were used to evaluate WDM/WC measures. Literature showed that to perform an economic evaluation of WDM/WC measures, the costs associated with the implementation of the WDM/WC measures, as well as the expected water saving from the implementation of the WDM/WC measure, must be known. Models were developed to estimate the expected water savings from different WDM/WC measures. The economic impacts of specific WDM/WC measures were investigated by using these models. Different economic models were developed to perform an economic evaluation of WDM/WC measures. WDM/WC measures were evaluated in terms of its economic feasibility. Economical evaluations of WDM/WC measures were also done as an alternative to the upgrading of infrastructure. In the last evaluation, the financing of WDM/WC measures through the deferral of capital cost, was investigated. Case studies from literature, where costs as well as water savings were available, were used to evaluate these WDM/WC measures by using the developed economic models. Cost estimates for the upgrading of infrastructure, to supply an equal amount of water as the water saving achieved in each case study, were done. These estimates were used to compare WDM/WC measure with the upgrading of infrastructure.
AFRIKAANSE OPSOMMING: Daar word al hoe meer druk op bestaande hulpbronne geplaas om voldoende water te lewer. Die fokus skuif na effektiewe bestuur van hierdie hulpbronne. Wateraanvraagbestuur/ Waterbewaring (WAB/WB) projekte word geïmplementeer om krisisse van water tekorte aan te spreek en tyd te wen om nuwe hulpbronne te ontwikkel. Dit is wel moontlik om WAB/WB in geïntegreerde waterbron bestuur in te sluit en WAB/WB as ʼn ekonomiese alternatief tot kapitale investering aan te wend. Om die ekonomiese aspekte van WAB/WB te ondersoek, is daar op bestaande ekonomiese evaluerings metodes gefokus om verskillende opsies met mekaar te vergelyk. Uit die literatuur is gevind dat die belangrikste aspekte vir die ontleding van WAB/WB alternatiewe i.t.v. hul ekonomiese waarde, die koste van implementering van die WAB/WB alternatief is en die waterbesparing wat deur die implementering van die WAB/WB alternatief verkry word. WAB/WB modelle is ontwikkel om die verwagte water besparing van bepaalde WAB/WB alternatiewe te beraam. Die moontlike ekonomiese impak van bepaalde WAB/WB alternatiewe is deur die gebruik van hierdie modelle ondersoek. Ekonomiese evaluerings modelle is opgestel om WAB/WB alternatiewe te ontleed. WAB/WB alternatiewe kan as ʼn ekonomiese haalbare projek geïmplementeer word waar die kostes van die waterbesparings meer as die kapitale koste van die projek is. WAB/WB alternatiewe kan ook meer ekonomies as die ontwikkeling van nuwe bronne of opgradering van ʼn bestaande netwerk wees. Laastens is die moontlikheid om WAB/WB as ʼn alternatief te finansier deur die besparing wat bereik kan word deur ʼn kapitale projek uit te stel, ondersoek. Gevalle studies uit die literatuur, waar die kostes en waterbesparings bekend is, is ontleed deur van hierdie ekonomiese evaluerings modelle gebruik te maak. Vir elk van die gevalle studies is ʼn koste vir die opgradering van die infrastruktuur beraam om die ekwivalente hoeveelheid water te voorsien as wat deur die WAB/WB alternatief bespaar is.

Muscle and hepatopancreas of blue crabs (Callinectes sapidus), collected from the Elizabeth River, Virginia, contained residues of polycyclic aromatic hydrocarbon (PAHs}, polychlorinated biphenyls (PCBs) and organochlorine pesticides. Analytical procedures involved dichloromethane extraction of lyophilized tissue, followed by molecular size and polarity-based purification of the extract. capillary gas chromatography with flame ionization detection and electrolytic conductivity detection was used for quantitation and tentative identification of the xenobiotic compounds. Mass spectrometry was used for confirmation of these identities. Contaminant concentrations were greater in hepatopancreas than in muscle in crabs from every site examined. Hepatopancreas PAH burdens were as high as 11 mg/kg dry weight, with an accompanying muscle level of 3.1 mg/kg. The PAHs present consisted mainly of alkylated low molecular weight compounds (e.g., acenaphthenes and naphthalenes), except near a creosote-impacted site. At the latter location, unsubstituted, higher molecular weight PAHs (e.g., pyrene and chrysene) dominated. Organochlorines, which included PCBs, 4,4'-DDE, and chlordane were found in lower concentrations. The effect of molting on xenobiotic accumulation in Crustacea was also examined. Molting is essential for crustacean growth and is integral to the reproductive process in some species. Molting and intermolt blue crabs were maintained in cages at the creosoted-impacted Elizabeth River site mentioned above. PAH concentration in muscle and hepatopancreas was measured for both molt groups. Newly molted blue crabs possessed statistically higher tissue burdens than intermolt crabs of three unsubstituted PAHs (cyclopenta(def)phenanthrene, fluoranthene, and pyrene) characteristic of the creosote-contaminated exposure site. Mean concentration of the three PAHs in hepatopancreas was 9560 μg/kg in newly molted crabs and 3360 μg/kg in intermolt crabs. Mean PAH concentration in muscle was 1380 μg/kg in new-molts and 498 μg/kg in intermolts. The elevated tissue burdens may be due to increased water uptake and shell permeability at ecdysis or decreased metabolism of PAH during the molt process. Newly molted blue crabs are regarded as a seafood delicacy and tissue burdens of xenobiotics, such as PAHs, may be of human health concern.

Natural resource conservation is important for human well-being, especially in fragile environments of developing countries. This study occurred in 2006 among 6,500 smallhold farmers residing along a 25-km segment of a heavily utilized river. Research objectives were to determine use and adoption constraints for 14 soil and water conservation practices (SWCPs). Farms were reportedly contributing to a decline in river water quality via soil erosion. Recent occupation of the upper watershed by immigrants magnified concerns that resource degradation could escalate. A multi-method approach incorporating quantitative surveys, qualitative interviews, and participant observation was used to interpret constraining factors within the biophysical and historical context of the watershed. Adoption rates for SWCPs were expected to be low (less than 20 percent). Increased formal education, income, access to information, and security of land tenure and soil characteristics, were expected to positively influence adoption. Data analysis included descriptive statistics and use of classification and regression trees. Results indicated that all sampled farms had adopted at least two SWCPs, with an average of six per farm. Favored practices were those that were easier to implement and more effective for resource protection and food production. Years in residence (tenure security) and income emerged as primary explanatory variables for adoption of SWCPs, while soil quality and formal education were secondary. Only 27 percent of surveyed farmers held title deeds, but the others perceived that land occupation conferred "ownership" and hence implemented SWCPs. A follow-up visit in 2009, after the region had endured a year of highly publicized ethnic conflict, immigration and farm expansion continued with SWCPs being adopted. Njoro communities mostly remained intact and appeared resilient. While small farms likely contribute to watershed-scale problems and declines in quality and quantity of water in the River Njoro, farmers have made remarkable strides--largely on their own--to conserve natural resources. Future research should examine how a general lack of infrastructure off-farm and study-site context contributes to reduced watershed-resource quality. Further protection of soil and water is best served by a more aggressive policy and extension education framework that links food security, household well-being, and natural resource management.

As the human population increases, the way we use and manage our supply of drinking water becomes even more important. The purpose of this study was to determine residents’ satisfaction level of and performance rating of new water savings devices installed in their apartments. Specifically the investigation focused on ratings of shower heads, kitchen faucet aerators, bath faucet aerators, and fill valve and flapper systems. This quantitative survey included residents at 4 apartment complexes in Tennessee using a paper questionnaire (N = 626). The participants were grouped by age, ethnicity, gender, and whether or not they had experienced both nonrestrictive devices or restrictive low flow devices within their apartment. An independent samples t test was conducted from the research questions for each of these 4 groups. The testing variables for each group consisted of the overall performances of the low flow devices, and the satisfaction of the time to get hot water to shower heads and faucets. There was no significant difference between the 4 grouping variables; residents aged 62 and over compared to 61 and younger, males compared to females, whites compared to nonwhites, and those who had experienced both nonrestrictive and restrictive devices while living in the same apartment when compared to these variables; performance rating of low flow shower heads, kitchen faucet aerators, bath faucet aerators, and low flow toilet devices. The variables also included the satisfaction rating of the time needed to get hot water to the new low flow shower heads and kitchen and bath faucet aerators. These findings support the effort to save clean water and reduce water and sewer costs by installing low flow shower heads, bath and faucet aerators, and water saving toilets. Mean score suggest satisfactory ratings were encountered in every testing category and within every group. In particular, the satisfactory mean score of residents who experienced both nonrestrictive and low flow devices while in the same apartment led to the conclusion that the reduction of water can be achieved satisfactorily in all types of residences.

In response to drought and regional growth in the arid western United States, urban water demand management is increasingly important. Single family residences use approximately 60% of their water consumption to irrigate landscapes often in excess of plant water requirements. This study utilized a quasi-experimental design to investigate outdoor water consumption and assess the effectiveness of a landscape water check conservation program. Study objectives included describing a contextualized landscape system to reveal variables influencing water use, identifying better ways to evaluate landscape water use, and more effectively targeting and delivering water conservation programs. The study was conducted during the 2004 and 2005 irrigation seasons in Logan City, Utah, in connection with a city-sponsored water check program. In Utah's sixth year of drought, free water checks were offered to all city households and delivered to 148 self-selected volunteers (2004) and 101 recruits from a target sample of above-average water users (2005). The site-specific approach incorporated landscape water checks to inspect residential landscapes, historical ETo data to create irrigation water schedules, survey data to assess water conservation behavior and the effectiveness of a water check program as a conservation tool, remote sensing data to develop household water budgets, and city water billing records to evaluate water consumption during a six-year period (2002 - 2007). The data analysis informed creation of a conceptual framework of the residential landscape system that describes the complex systems thinking required to use water effectively. Water use case studies illustrate the interplay of system domains; site, plant material, irrigation technology, and behavior. Several assessment and monitoring tools were developed to aid in data analysis, which include the Urban Landscape Water Index and Conservation Outcomes Assessment and Intervention Evaluation Tools. Key research findings reveal the influence of sprinkler system controllers, adoption of recommended water schedule and conservation measures, and residential mobility on subsequent water use. Research findings shed light on the complex and contextualized nature of water use in relation to residential landscapes and on methodological issues involved in evaluating conservation program effectiveness. These findings have important implications for the design and implementation of outdoor water conservation programs.

Rainwater harvesting, the act of capturing and storing rain, is an ancient practice that is increasingly utilized today by communities to address water supply needs. This thesis examines whether domestic rainwater harvesting systems (DRWHS) can be a sustainable solution as defined by social, water quality, and technical feasibility for water security in semi-arid, rural environments. For this study, 50 surveys and 17 stored rainwater analyses were conducted in San Jose Xacxamayo, Mexico, in conjunction with my Peace Corps work of implementing 82 DRWHS. Results showed that all DRWHS were socially feasible because of cultural acceptance and local capacity. Water quality analyses showed that four DRWHS contained coliform bacteria; deeming water unfit for human consumption. Technical feasibility, examined through climate analyses, showed an average year-round reliability of 20-30% under current and future rainfall regime. The DRWHS can be a sustainable water supply option with roof expansion and treatment prior to consumption.

This thesis research employs a multi-pronged analysis approach to contribute to the existing knowledge regarding land use and water quality in southern Miami Dade County. Nutrient concentrations for TP, NOx-N, and NH3-N were evaluated for water quality monitoring stations across seven canals for two time periods: 1990-2003 and 2009-2014. Overall, the sites did not surpass the mandated TP threshold but a number of sites exceeded the NOx-N and NH3-N criteria set by multiple government agencies. Statistical tests demonstrated that the sites had differing distributions, not sharing similar median concentrations. Land use classifications were derived for the area interest for the years 1994 and 2013. Regression models relating land use classifications to nutrient concentrations at various spatial scales provided mixed results. Lastly, a trend analysis for nutrient concentrations at the stations for 1990-2003 and 2009-2014 demonstrated that there were either no trends or a decreasing trend at most sites.

This study addresses the central problem of how the behaviour of individuals may be co-ordinated to manage collective natural resources, and in particular, to what degree this can be achieved through voluntary, community based means under a free market policy regime. This question was explored by researching how local groups known as Landcare, or Care groups, are managing waterways in Waikato, New Zealand, and specifically by examining their effectiveness in controlling non-point source contaminants to water originating from agricultural land.An action research approach was used to investigate research questions regarding what motivates actors to support activity to enhance water quality, the effectiveness of such activity in addressing non-point source discharges to water, and the equity issues which are associated with environmental management through Landcare. This study suggests that neo-liberal philosophies of governance, while favouring voluntary resource management, disregard the conditions which, in practice, underpin effective and equitable examples of this type of activity. A call is therefore made for a more active role for government, in directly supporting local action, in compensating for the impacts of free-market policies on natural resource use, and in facilitating the representation of the diversity of views in environmental management. Action research, participatory planning, and other learning based and communicative processes could be usefully employed to guide and inform such interventions
Doctor of Philosophy (PhD)

With the worldâ s population growing at a rate faster than the rate at which natural resources are being replenished, the challenge for governments and the worldâ s citizens is how to conserve resources in order to provide a sustainable level of natural resources for the future. Conserving natural resources includes educating the citizens of the world on the connection between natural resource depletion and their levels of consumption of resources, such as energy and water. To help alleviate the increasing burden the worldâ s growing population is placing on natural resources, sustainability should be a part of college studentsâ education in their field of study and in preparing them to become good citizens. This education should take place in the classroom and other activities, including athletics, community organizations, and in their residence life. Teaching students living in on-campus residence halls conservation activities provides information that students can use in their private lives when setting up their own households. On-campus residence halls also provide an opportunity to evaluate any gender differences related to conservation activities since the demographics of the residence halls vary from all-female, to co-ed, to all-male students. Virginia Polytechnic Institute and State University (Virginia Tech) was the location for a study on promoting environmentally-relevant behavior (ERB) among students residing in on-campus residence halls. The objective of this study was to investigate the relationship between the use of educational strategies and natural resource consumption by promoting ERB among students living in the residence halls during the spring and fall semesters of the 2009 calendar year. Using the literature on promoting ERB, five different strategies were designed for promoting water and electricity conservation. Each strategy involved different stimuli to promote student participation in ERB. The information provided the students included reasons why ERB was important and specific actions to take to conserve resources. In three of the strategies, students were provided the results of their conservation efforts monthly during the study period. The Virginia Tech Office of Residence Life provided detailed information for the 49 on-campus residence halls, including buildingsâ characteristics such as heating and cooling methods, age, construction, renovation history, square footage, if the buildings contained offices or classrooms, and student population figures. Variability among the buildings was eliminated by comparing these differences, and then a random numbers table was used to assign each of the buildings to one of the five different groups. The strategy for each group was applied to four residence halls -- two dormitories and two Greek Houses, for a total of twenty buildings. In each strategy more stimuli were applied in an effort to produce higher consumption reductions. The Virginia Tech Office of Facilities provided four-years historical electricity and seven-years historical water usage, and provided monthly usage for each building during the study period. Electricity consumption reduction was promoted in all twenty halls but water consumption reduction was promoted only in the dormitories, as the University was unable to track water consumption for any one individual Greek House. The historical data showed that water usage per student was higher in most of the female-occupied dormitories, but no statistical difference was seen with regards to historical electricity usage and gender. Percent change in per student usage â kilowatt hours for electricity and gallons for water â was the calculation used to determine change in ERB. The results of this research showed a general relationship between educational strategies and natural resource consumption reduction over both study periods. However, except for the Greek-House Spring semester results, no statistical significant difference was found between any of the different study groups. Electricity reductions were achieved in seventeen of twenty residence halls during the first semester and in all but one residence hall during the second semester. Water reductions were achieved in five of ten dormitories during the first semester and in six of nine dormitories in the second semester. However, the use of more strategies did not lead to a higher percentage of reductions. During the first semester, a statistically significant difference was found in water usage and gender and the difference did not support a female predisposition for ERB. Decreases were achieved in excess of 10% in the male-occupied dormitories, but only a minimal reduction or increases were achieved in any of the dormitories that included female residents. After the first month of the second semester, similar results were seen relative to gender, so additional posters and prompts were placed in the female-occupied dormitories. As a result, water reductions were achieved in six dormitories with only small increases in the other three, and the semester final results did not show a statistical significant difference between genders. The lack of statistical difference between the study groups could be a result of contamination, the active environmental organizations on campus, or an observational effect. The study was contaminated within the first two weeks of the study period when all residence halls across campus learned of the research and requested their inclusion in the study. Since, the residence halls in the control groups were advised of their inclusion in the study, the students may have demonstrated ERB because of the knowledge they were being observed. A survey sent to the students living in the study residence halls revealed that 94.6% of the students had knowledge of the study, and that 77% participated in ERB. Students showed a propensity for ERB when they were informed on their consumptive behaviorsâ effects on natural resource depletion, and by being provided with actions they could take to change their behaviors. This research did not show that adding strategies of feedback and group leaders to information increased the percentage of consumption reductions in college students residing on Virginia Techâ s campus.
Master of Science

Climate change and over-use of natural resources impacts ecosystems worldwide. Understanding physical impacts from climate and natural resource use on biological processes at multiple scales of spatial and ecological organization is needed to make useful predictions under global change scenarios. Mountain aquatic ecosystems are of particular concern because they are sensitive to climate change, represent hot spots of biodiversity, and they integrate atmospheric, terrestrial and aquatic processes into biological responses. The objective of this dissertation is to quantify physical impacts and biological responses of climate and water use on mountain aquatic ecosystems in the Western United States. In Chapter 1, I developed a data set of ice break-up dates using remote sensing techniques for mountain lakes across the Sierra and Cascade Mountain Ranges coupled with downscaled climate data to quantify drivers of lake ice phenology. I developed a predictive linear mixed effects model and used and ensemble of 15 global climate models to project changes in lake ice break-up dates through the 21^st century. The results suggest that low snowpack and increased energy fluxes associated with elevated air temperatures drive earlier ice break-up dates. Projections of ice break-up show that ice break-up will be 61 ± 5 days if greenhouse gas emissions are not reduced. In Chapter 2, I analyzed specific ecological responses to earlier ice break-up dates in Castle Lake, California (a natural, sub-alpine lake). I predicted that consumer (Brook Trout; Salvelinus fontinalis) energetics and habitat use would be regulated by either climate driven water temperature or variation in food availability. The data suggest that earlier ice break-up results in a longer duration of surface water temperatures > 15 °C, coupled with decreased and increased food production in the pelagic and littoral zones, respectively. Isotopic and telemetry data showed that consumer resources and habitat use were driven by water temperature and were independent of food availability. In early ice break-up years, consumers grew less because they were thermally excluded from productive littoral zones when water temperatures were warmer for longer periods of time relative to late ice break-up years. In Chapter 3, I demonstrate that decreased streamflow in mountain rivers can reduce abundance and size structure of food supply to drift foraging Rainbow Trout (Onchorhynchus mykiss). In response to changes in streamflow and food availability, trout abandoned their energetically profitable drift foraging strategy and actively searched for prey. The shift in foraging behavior resulted in negative bioenergetic efficiencies in flow impaired sites. Taken collectively this research demonstrates that both predictable and unpredictable consequences of physical change drive biological responses across spatial gradients, ecosystem types, and levels of ecological organization.

As California contends with climate change and more extreme cycles of drought and deluge, water management agencies and conservation groups are looking towards solutions to the decreasing reliability of imported water supplies. Stormwater has historically been perceived as a threat to development but when captured properly, it presents a resource that can augment local water supplies. Solutions to water supply issues in California have traditionally employed technical and centrally controlled methods for importing water, but there is a growing understanding that parcel-level capture through vegetated swales presents an opportunity for reducing the impact that development has on California’s hydrology. Vegetated swales mimic nature’s effectiveness in reducing runoff speeds, removing pollutants and increasing groundwater supplies. No less a piece of California’s water infrastructure than canals and dams, these swales bring water infrastructure into the context of the California landscape. My report for the Chino Basin Water Conservation District analyzes the feasibility of installing vegetated swales in the Chino Basin region.

[EN] First chapter uses California's drought to identify the economic threats of water scarcity on food, energy and environmental systems as a way to introduce the multiple interactions between these resources. The second part of this first chapter introduces the focus of the dissertation, the water-energy nexus, presents a literature review identifying gaps, states the main and specific research objectives and the research questions, explains the research approach, and describes the organization of the dissertation. Second chapter develops an end-use model for water use and related energy and carbon footprint using probability distributions for parameters affecting water consumption in 10 local water utilities in California. Statewide single-family water-related CO2 emissions are 2% of overall per capita emissions, and locally variability is presented. The impact of several common conservation strategies on household water and energy use are assessed simulating different scenarios. Based on the this model, Chapter 3 introduces a probabilistic two-stage optimization model considering technical and behavioral decision variables to obtain the most eco-nomical strategies to minimize household water and water-related energy bills and costs given both water and energy price shocks. Results can provide an upper bound of household savings for customers with well-behaved preferences, and show greater adoption rates to reduce energy intensive appliances when energy is accounted, result-ing in an overall 24% reduction in indoor water use that represents a 30 percent reduc-tion in water-related energy use and a 53 percent reduction in household water-related CO2 emissions. To complete the urban water cycle, Chapter 4 develops first an hourly model of urban water uses by customer category including water-related energy consumption and next I calibrate a model of the energy used in water supply, treatment, pumping and wastewater treatment by the utility, using real data from East Bay Municipal Utility District in California. Hourly costs of energy for the water and energy utilities are assessed and GHG emissions for the entire water cycle estimated. Results show that water end-uses account for almost 95% of all water-related energy use, but the 5% managed by the utility is still worth over $12 million annually. Several simulations analyze the potential benefits for water demand management actions. The total carbon footprint per capita of the urban water cycle is 405 kg CO2/year representing 4.4% of the total GHG emissions per capita in California. Accounting for the results obtained in Chapters 2 to 4, Chapter 5 describes a simple but powerful decision support system for water management that includes water-related energy use and GHG emissions not solely from the water operations, but also from final water end uses, including demands from cities, agriculture, environment and the energy sector. The DSS combines a surface water management model with a simple groundwater model, accounting for their interrelationships, and also includes explicitly economic data to optimize water use across sectors during shortages and calculate return flows from different uses. Capabilities of the DSS are demonstrated on a case study over California's intertied water system over the historic period and some simulations are run to highlight water and energy tradeoffs. Results show that urban end uses account for most GHG emissions of the entire water cycle, but large water conveyance produces significant peaks over the summer season. The carbon footprint of the entire water cycle during this period, according to the model, was 21.43 millions of tons of CO2/year, what was roughly 5% of California's total GHG emissions. The last two chapters discus and summarize the thematic and methodological contribu-tions and looks for further research presenting and discussing the research gaps and research questions that this dissertation left open.
[ES] El primer capítulo utiliza la sequía de California para identificar las amenazas económicas de la escasez de agua en los sistemas de producción de alimentos, energético y medioambiental para presentar las múltiples interacciones entre estos recursos. La segunda parte del primer capítulo centra el objetivo de la tesis, la relación entre el agua y la energía, presenta la revisión de la literatura identificando los vacíos, describe los objetivos y las cuestiones que busca responder esta investigación, explica la metodología seguida, y describe la organización de la tesis. En el segundo capítulo se desarrolla un modelo de usos finales de agua, contando con la energía y las emisiones de GEI asociados utilizando distribuciones de probabilidad para los parámetros que afectan al uso del agua en 10 ciudades en California. Como resultados principales se obtiene que las emisiones de GEI asociadas al consumo residencial de agua representan el 2% del total de emisiones per cápita, y se presenta la variabilidad debida a las condiciones locales. Los impactos de algunas prácticas comunes de ahorro de agua y energía son calculadas simulando diferente escenarios. Basado en ese modelo, el Capítulo 3 se presenta un modelo de optimización probabilísticos en dos periodos considerando variables de decisión de modificaciones técnicas y de comportamiento en relación al consumo de agua para obtener las estrategias más económicas para minimizar las facturas de agua y energía. Los resultados proporcionan un límite superior para el ahorro doméstico, y muestran mayores tasas de adopción para reducir usos de agua que son más intensivos en consumo energético cuando la energía se incluye, resultando en una reducción del 24% de uso de agua adentro de las casas, que representa un 30% en reducción de energía y un 53% de emisiones de GEI, ambos relacionados con el consumo de agua. Para completar el ciclo urbano del agua, el Capítulo 4 desarrolla primero un modelo horario de usos de agua incluyendo la energía asociada y después se calibra un modelo de agua y energía en el abastecimiento, tratamiento y bombeo de agua, y el tratamiento de agua residual, utilizando datos reales de East Bay Municipal Utility District en California. Los costes horarios de energía para las compañías de agua y energía, así como las emisiones de GEI son estimadas. Los resultados muestran que los usos finales son responsables del 95% de la energía relacionada con el uso del agua, pero que el 5% restante tiene un coste de 12 millones de dólares anualmente. Teniendo en cuenta los resultados obtenidos en los capítulos 2, 3 y 4, el Capítulo 5 describe un sistema de apoyo de decisión (SSD) para gestión de recursos hídricos incluyente energía y emisiones de GEI no sólo de la gestión del agua, sino también de usos finales del agua, incluyendo demandas urbanas, agrícolas, ambientales y del sector energético. El SSD combina un modelo de agua superficial con uno de agua subterráneo, incluyendo sus interacciones, y también incluye explícitamente datos económicos para optimizar el uso del agua durante periodos de sequía. Las posibilidades del SSD son demostradas en un caso de estudio aplicado a un modelo simplificado del sistema de recursos hídricos de California. Los resultados muestran que los usos finales del agua en zonas urbanas son responsables de la mayoría de las emisiones de GEH, pero que las grandes infrastructures de transporte de agua producen importante picos en verano. De acuerdo con el modelo, la huella de carbón del ciclo del agua en California es de 21.43 millones de toneladas de CO2/año, lo que significa aproximadamente el 5% del total de emisiones de GEI del estado. Los últimos dos capítulos resumen y discuten las contribuciones temáticas y metodológicas de esta tesis, presentando nuevas líneas de investigación que se derivan de este trabajo.
[CAT] El primer capítol utilitza la sequera de Califòrnia per a identificar les amenaces econòmiques de l'escassesa d'aigua en els sistemes de producció d'aliments, energètic i mediambiental per a presentar les múltiples interaccions entre estos recursos. La segona part del primer capítol centra l'objectiu de la tesi, la relació entre l'aigua i l'energia, presenta la revisió de la literatura identificant els buits, descriu els objectius i les qüestions que busca respondre esta recerca, explica la metodologia seguida, i descriu la organització de la tesi. Al segon capítol es desenvolupa un model d'usos finals d'aigua, comptant amb l'energia i les emissions de GEH associats utilitzant distribucions de probabilitat per als paràmetres que afecten a l'ús de l'aigua en 10 ciutats en Califòrnia. Com a resultats principals s'obté que les emissions de GEH associades al consum residencial d'aigua representen el 2% del total d'emissions per càpita, i es presenta la variabilitat deguda a les condicions locals. Els impactes d'algunes pràctiques comunes d'estalvi d'aigua i energia són calculades simulant diferent escenaris. Basat en eixe model, al Capítol 3 es presenta un model d'optimització probabilístics en dos períodes considerant variables de decisió de modificacions tècniques i de comportament en relació al consum d'aigua per a obtindre les estratègies més econòmiques per a minimitzar les factures d'aigua i energia. Els resultats proporcionen un límit superior per a l'estalvi domèstic, i mostren majors taxes d'adopció per a reduir usos d'aigua que són més intensius en consum energètic quan l'energia es incluïda, resultant en una reducció del 24% d'ús d'aigua a dins de les cases, que representa un 30% en reducció d'energia i un 53% d'emissions de GEH, ambdós relacionats amb el consum d'aigua. Per a completar el cicle urbà de l'aigua, el Capítol 4 desenvolupa primer un model horari d'usos d'aigua incloent l'energia associada i després es calibra un model d'aigua i energia en l'abastiment, tractament i bombeig d'aigua i al tractament d'aigua residual, utilitzant dades reals de East Bay Municipal Utility District en Califòrnia. Els costs horaris d'energia per a les companyies d'aigua i energia, així com les emissions de GEH són estimades. Els resultats mostren que els usos finals són responsables del 95% de l'energia relacionada amb l'ús de l'aigua, però que el 5% restant té un cost de 12 milions de dolars anualment. Algunes simulacions analitzen els beneficis econòmics potencials de mesures de gestió de demanda d'aigua. La petjada de carbó total del cicle urbà de l'aigua s'estima en 405 kg CO2/any representant el 4.4% de les emissions per càpita en Califòrnia. Tenint en compte els resultats obtesos en els capítols 2, 3 i 4, el Capítol 5 descriu un sistema de suport de decisió (SSD) per a gestió de recursos hídrics incloent energia i emissions de GEH no sols de la gestió de l'aigua, sinó també del úsos finals de l'aigua, incloent demandes urbanes, agrícoles, ambientals i del sector energètic. El SSD combina un model d'aigua superficial amb un d'aigua subterrànea, incloent les seues interrelacions, i també inclou explícitament dades econòmiques per a optimitzar l'ús de l'aigua durant períodes de sequera. Les possibilitats del SSD són demostrades en un cas d'estudi aplicat a un model simplificat del sistema de recursos hídrics de Califòrnia. Els resultats mostren que els usos finals de l'aigua en zones urbanes són responsables de la majoria de les emissions de GEH, però que les grans infrastructures de transport d'aigua produïxen important pics a l'estiu. D'acord amb el model, la petjada de carbó del cicle de l'aigua a Califòrnia és de 21.43 milions de tones de CO2/any, el que significa aproximadament el 5% del total d'emissions de GEH a l'estat. Els últims dos capítols resumeixen i discuteixen les contribucions temàtiques i metodològiques d'esta tesi, presentan
Escrivà Bou, À. (2015). The Water-Energy Nexus: a bottom-up approach for basin-wide management [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59451
TESIS
Premiado

Numerous studies have analyzed isotopic variation of meteoric and dripwater in karst environments for paleoclimate reconstructions or aquifer recharge capacity. What is poorly understood is how the isotopic signal of δ18O and δ2H is transferred through the hydrologic cycle based upon storm type, frequency, intensity, and teleconnection activity in the tropical karst areas. At Harrison’s Cave, Barbados, a Hobo Onset event data logger was attached to a tipping bucket rain gauge to count the tips and record the total rainfall every 10 minutes. In the cave a Hobo data logger was used to record relative humidity and temperature at 10-minute intervals. Rainwater, dripwater, and stream water samples were collected at a weekly resolution and refrigerated before sample analysis. The study period was from July, 2012 to October, 2013, with data from the data loggers only until June, 2013 due to inability to reach the study site. The samples were analyzed using the Picarro Cavity Ring Down Spectroscopy Unit-Water L1102-I through laboratories at the University of Kentucky and the University of Utah. The samples were reported in per mil and calibrated. The teleconnection (NAO, AMO, and ENSO) and other atmospheric data were obtained from the Climate Prediction Center or the NOAA Earth System Research Laboratory-Physical Sciences Division. The weekly isotope signatures were linearly regressed against total rainfall for Harrison’s Cave and surface temperature with no statistically significant correlation, indicating the amount effect was not present at a weekly resolution. The amountweighted precipitation δ18O values were calculated on a monthly basis and compared to TRMM monthly rainfall and island-wide monthly rainfall, and a statistically significant negative correlation was found between both datasets. This confirmed that the amount effect dominates the island’s rainfall isotopic signature at a monthly resolution, and that specific atmospheric influences represented in weekly rainfall were less influential on a weekly basis. It is hypothesized that the variation in weekly rainfall is due to quick initiating, rain-out, and dissipation of convective storm systems over the island. In terms of evaporative influences, the samples do not deviate much from the Global Meteoric Water Line (GMWL), indicating minimal evaporation, which is typical for tropical locations. When the d-excess parameters were calculated, there were distinct variations with minimal evaporation occurring in the 2013 calendar year. This is attributed to coastal storm formation in the tropics.

Increased demands on water supplies caused by population expansion, saltwater intrusion, and drought have led to water shortages which may be addressed by use of recycled water as recycled water products. Study I investigated recycled water production in Florida and California during 2009 to detect gaps in distribution and identify areas for expansion. Gaps were detected along the panhandle and Miami, Florida, as well as the northern and southwestern regions in California. Study II examined gaps in distribution, identified temporal change, and located areas for expansion for Florida in 2009 and 2015. Production increased in the northern and southern regions of Florida but decreased in Southwest Florida. Recycled water is an essential component water management a broader adoption of recycled water will increase water conservation in water-stressed coastal communities by allocating recycled water for purposes that once used potable freshwater.