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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.
1

Development and application of PARCHED-THIRST : a user-friendly agrohydrological model for improving dryland cropping systems

Young, Mark Damion Bede January 2002 (has links)
No description available.
2

Water saving mechanisms, a policy analysis

Stautberg, Edward Berwind 03 February 2014 (has links)
Distributed water conservation provides significant benefits to overall water availability, particularly if adopted at a large scale. Conservation strategies, such as rainwater harvesting, xeriscaping, and permeable pavements are desirable because they conserve water, increase recharge near dwellings, and reduce dangerous stormwater runoff. Though conserving water is an admirable goal, justifying retrofits for water conservation mechanisms to existing structures is difficult because water prices are very low in much of the United States. However, stormwater regulations and the increasing implementation of stormwater utilities by cities enable other avenues of adoption for these practices. This thesis reviews water conservation strategies, examines local and state policies, and presents a “model policy”. The model policy design uses a comparative approach to identify useful incentives and aggregates best management and policy practices from several states to serve as a guide and accelerate implementation. / text
3

ASSESSING THE RELIABILITY OF ROOFTOP RAINWATER HARVESTING FOR DOMESTIC USE IN WESTERN KENYA

Mundia, Clara 01 May 2010 (has links)
In many developing countries, the stress of rapidly growing populations, mismanagement of resources and changing climate has created a burden on already compromised water resources. In Africa, where a significant proportion of the population is without access to improved water source, the urgency for clean available water sources to sustain healthy and productive human and natural populations has become a priority. As a water scarce country, Kenya has seen an increased investment in rainwater harvesting (RWH) projects to harness the vastly untapped rainwater resource, particularly in rural areas. Most of RWH literature is centered on the potential and implementation of rainwater harvesting systems, however not much focus has been placed on examining the demand satisfaction of these systems. This study investigates the reliability of rooftop rainwater harvesting (RRWH) as a key priority source of water supply for domestic use in three towns in Western Kenya: Kisumu, Nakuru and Lodwar. This was done using two approaches (1) the fraction of time water was available and (2) the fraction of time that a minimum demand was met, with acceptable reliability of 0.95 or higher. Actual rainfall data and RRWH parameters were used to produce supply/demand simulations of the system under Constant-Demand and Responsive-Demand scenarios over ten years. It was observed that all towns achieved acceptable reliability values for RRWH in terms of water availability however Lodwar only achieved demand satisfaction below 0.95. This study concluded that though RRWH cannot satisfy the minimum demand requirement through all days of the year, it is more than able to provide an alternative water supply for the domestic household in periods of long dry spells or when primary water source are inadequate.
4

RainScapes

Daily, Cado, Wilkins, Cyndi 02 1900 (has links)
2 pp. / RainScapes are the ultimate in water efficient landscaping. RainScapes are beautiful landscapes that once established rely entirely on rain and stormwater (gray water too if available)while preserving tap water for indoor and drinking water needs.
5

The promotion of rainwater harvesting as a supplementary source of domestic water in Kigali, Rwanda- A feasibility study

Sully, Robert Peter 14 February 2007 (has links)
Student Number : 7336898 - MSc (Eng) research report - School of Civil and Environmental Engineering - Faculty of Engineering and the Built Environment / Theme and Context Despite being the source of two of Africa’s greatest rivers, the Nile and the Congo, Rwanda is a water scarce country and 50% of the citizens of the capital, Kigali, do not have access to safe drinking water. Rwanda’s tragic history of violent social upheaval combined with regional macro-economic factors and the effects of globalization have made this tiny country one of the poorest on the African continent. Aim and Objectives of this Study The aim of this report is to establish the value that Rainwater Harvesting holds as a supplementary water source for the city of. To evaluate this potential intervention, the suitability of the climate for the harvesting of rainwater is reviewed as well as the availability of the required resources and the effect that the prevailing social environment may have on an implementation program. The current developments in the practice of Rainwater Harvesting are researched and ways in which Rainwater Harvesting could be utilized are explored as well as the possible impediments that might be encountered. Scope and Methodology Adopted The scope of the report includes: 1. Providing an overview of the country both geographically as well as socially. 2. Establishing the need for alternative water sources by: a. Reviewing the present water supplies for the city particularly with regard to their vulnerability to the rapid environmental degradation being experienced within the country, b. Reviewing the prevailing water/health nexus. 3. Investigating metrological records, specifically rainfall patterns, and the quality of the statistics. 4. Review international trends and research in rainwater harvesting specifically in poor countries. 5. Considering obstacles to implementing a wide-ranging scheme to harvest rainwater. The methodology adopted includes: 1. Reviewing published research on the subject of Rainwater Harvesting techniques and implementation. 2. Attending symposia on the subject. 3. Meeting with water practitioners both in the public sector as well as in NGOs to establish the current status of water availability, quality and consumption. 4. Conducting on-site research into water sourcing problems in and around Kigali. 5. Designing, sizing and costing hypothetical installations suitable for local conditions. Summary of Main Findings, Conclusions and Recommendations Although the climate and topography are very favorable to the use of Rainwater Harvesting, this report finds that the promotion of Rainwater harvesting is just one of a number of possible interventions which should be pursued in order to improve the availability of water to the citizens of Kigali The cost and sophistication of Rainwater Harvesting schemes vary considerably but at the lower end of the scale the technology would be affordable to most Kigali residents and the community has the potential human resource to be trained to execute the work. Obstacles to this approach include ignorance about the safety of storing water, the comparative low cost of municipal water the perception that water collection is the responsibility of a family’s women and children. This report also found that a household using a Rainwater Harvesting scheme is likely to require some supplementary water on occasions. Furthermore, as the potential to catch sufficient water is a function of the ratio of a dwelling’s roof area to the number of inhabitants, its efficacy is limited in densely inhabited poor communities. Strong leadership and coordination would be necessary for a successful wideranging Rainwater Harvesting implementation project. In addition a coordinated educational programme will have to be conducted to dispel myths about stored water and to create the required skills base. The statutes and bylaws regarding water would also have to be reviewed to avoid legal impediments. This report concludes that rainwater harvesting cannot be relied upon to fulfill all the communities’ water needs but it can go a long way to improving the general access to safe water and in so doing reduce the time and labour presently demanded, mainly of women and children, in the carrying of heavy loads of water.
6

Canopy Change Assessment and Water Resources Utilization in the Civano Community, Arizona

Pan, Yajuan 12 1900 (has links)
The Civano community of Tucson, Arizona, is built for sustainability. Trees and plants are precious resources in the community and balancing human needs and natural resources. The design of rainwater harvesting systems and the usage of reclaimed water inside the community effectively irrigate plants and save drinking water. This project estimates canopy changes over time and explores the effect of water resources on plant growth for developed areas and natural areas, respectively. This project generates land cover classifications for 2007, 2010, and 2015 using supervised classification method and measures canopy cover change over time. Based on City of Tucson Water “harvesting rainwater guide to water-efficient landscaping”, this project discusses if water supply meets plant water demand in the developed areas of the community. Additionally, the normalized difference vegetation index (NDVI) data for developed area and natural area over ten years are compared and provide a correlation analysis with water sources. The results show that canopy cover across the entire community decreased from 2007 to 2010, then increased from 2010 to 2015. Water supply in the developed areas is sufficient for plant water demand. In natural areas plant growth changes dramatically as a result of precipitation fluctuation. In addition, it’s proved that 2011 National Land Cover Database (NLCD) tree canopy underestimates canopy cover in the Civano community. The final products not only provide the fundamental canopy cover data for other studies, also serve as a reference of water efficient landscaping within a community.
7

Decision support system for sustainable rainwater harvesting in South Africa

Mwenge Kahinda, Jean-Marc 05 May 2011 (has links)
To reconcile its scarce water resources with the ever increasing demand for fresh water, the South African government continues to explore and investigate various demand management and water supply options such as: effluent reuse, interbasin water transfers, rainwater harvesting (RWH), water conservation as well as sea water desalinisation. RWH is an old but underutilised technology that can play a key role in the improvement of rural livelihoods, thus the need to investigate the potential it holds for South Africa. This thesis presents the Rainwater HArvesting Decision Support System (RHADESS) that was developed to facilitate the integration of three streamlined categories of RWH in the management and development of the country’s water resources at the quaternary catchment scale (± 500 km2). Using biophysical and socioeconomic datasets, RHADESS assesses the RWH footprint of any given area of South Africa. Although physical factors are important parameters in the assessment of the RWH suitability of a given area the non‐consideration of ecological and socioeconomic parameters lead to inappropriate targeting of RWH. Once the footprint is determined, the ecohydrological impact of RWH as reduction in river flow can be established. Despite the increasing adoption of RWH, very little is known about its potential ecohydrological impact. This thesis contributes to understanding these impacts for different levels of adoption of RWH at the quaternary catchment scale. Finally, RHADESS sizes the RWH tank per quaternary catchment, assesses its water security and calculates the area of land needed for a household to achieve food security when RWH is implemented. The decision support system was tested in two quaternary catchments which have contrasting rainfall regimes, the semi‐arid C52A and the humid V13D.
8

Rainwater Harvesting in Rural Kenya : Reliability in a Variable and Changing Climate

Aroka, Nelly January 2010 (has links)
<p>In many parts of the tropics irregular and erratic rainfall has great national economic as well as socio-economic effects. In Kenya, where a large part of the population live in rural areas and rainfed agriculture is the main livelihood, droughts and floods have farreaching impacts on communities. One form of mitigating the negative effects of drought is the implementation of simple, small-scale, low cost schemes called rainwater harvesting. This involves the capture, storing and redirection of rainfall, runoff, and groundwater. In Kenya, such schemes are being implemented in rural areas through different actors. Two Non-Governmental Organizations involved are the Kenya Rainwater Association and the German Agro Action that work in Tseikuru, a semi-arid area with water availability and sanitation issues. The main livelihood is agropastorialism and there is little experience with rainwater harvesting. Commonly, water is collected by digging shallow holes into dry river beds where groundwater tables are high. These areas are prone to contamination and could be situated many kilometres away, making water collection laborious. By implementing rainwater harvesting schemes water availability as well as water quality is expected to be improved. However, due to great rainfall variability and effects of climate change these schemes may fall short of their expectations. Also the potential change on water demand may affect communities’ response to prolonged dry spells. This study aims to examine whether the implemented rainwater harvesting schemes in rural Tseikuru are reliable in times of adverse rainfall and if increased water availability (and potentially also increased water demand) affects the communities’ vulnerability towards droughts. The study is based on interviews with local stakeholders and technicians during a Minor Field Study in Tseikuru, as well as statistical analysis on rainfall data over the area and literature studies. Results showed that rainwater harvesting schemes are generally successful in supplying readily available and safe water. However the rural population of Tseikuru have not completely abandoned their old habits of collecting water from dry riverbeds, choosing instead to treat the schemes as an alternative source to water, thereby avoiding dependency towards the schemes.</p>
9

Rainwater Harvesting in Rural Kenya : Reliability in a Variable and Changing Climate

Aroka, Nelly January 2010 (has links)
In many parts of the tropics irregular and erratic rainfall has great national economic as well as socio-economic effects. In Kenya, where a large part of the population live in rural areas and rainfed agriculture is the main livelihood, droughts and floods have farreaching impacts on communities. One form of mitigating the negative effects of drought is the implementation of simple, small-scale, low cost schemes called rainwater harvesting. This involves the capture, storing and redirection of rainfall, runoff, and groundwater. In Kenya, such schemes are being implemented in rural areas through different actors. Two Non-Governmental Organizations involved are the Kenya Rainwater Association and the German Agro Action that work in Tseikuru, a semi-arid area with water availability and sanitation issues. The main livelihood is agropastorialism and there is little experience with rainwater harvesting. Commonly, water is collected by digging shallow holes into dry river beds where groundwater tables are high. These areas are prone to contamination and could be situated many kilometres away, making water collection laborious. By implementing rainwater harvesting schemes water availability as well as water quality is expected to be improved. However, due to great rainfall variability and effects of climate change these schemes may fall short of their expectations. Also the potential change on water demand may affect communities’ response to prolonged dry spells. This study aims to examine whether the implemented rainwater harvesting schemes in rural Tseikuru are reliable in times of adverse rainfall and if increased water availability (and potentially also increased water demand) affects the communities’ vulnerability towards droughts. The study is based on interviews with local stakeholders and technicians during a Minor Field Study in Tseikuru, as well as statistical analysis on rainfall data over the area and literature studies. Results showed that rainwater harvesting schemes are generally successful in supplying readily available and safe water. However the rural population of Tseikuru have not completely abandoned their old habits of collecting water from dry riverbeds, choosing instead to treat the schemes as an alternative source to water, thereby avoiding dependency towards the schemes.
10

Effects of Storage Container Color and Shading on Water Temperature

Clayton, James Brent 2011 May 1900 (has links)
Rainwater harvesting (RWH) is a method of capturing rainfall from a catchment surface and storing it for later use. Though it has been around for thousands of years, its popularity and use has been increasing in recent years and water quality within RWH systems has become a concern. Water temperature is a parameter of water quality and storage container color and shading affect this temperature. Four different colors and three different shadings were applied to twelve rainwater storage barrels. Water temperature of these barrels was measured over twenty weeks during a Texas summer. During the initial ANOVA model, it was determined that the color and shade variables had an interaction and thus both together had an effect on the water temperature. Though the individual treatment variables could not be analyzed and compared statistically, the trends showed that light colors and higher shading caused lower water temperatures in the storage containers. Also, the color had more pronounced effect than shading on water temperature inside the barrels.

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