The limitation of urban water supplies is becoming worse each year. Several studies estimate that 2 billion of the world’s population will suffer from water scarcity by 2050; and urbanization rates is placing an even greater challenge in providing the infrastructure needed to serve growing populations. At this point, rainwater may be considered as the most critical, untapped water resource in a global aspect. Rainwater Harvesting Systems (RWHS) have tremendous potential, not only to provide sufficient water supply, but also to serve as a valuable stormwater management tool. Despite these benefits, RWHS is still not popular among ordinary people in urban situations, due mostly to high installation costs. This study aims to explore the equitable cost reallocation of residential rainwater harvesting systems between the urban utility, land developer and homebuilder, and individual homeowner sectors. It may be possible to redistribute the cost equitably among the parties based on potential benefits received,thereby making RWHS more affordable and more viable as a new water supply for urban areas. / text

<p> </p><p>This study is a bachelor degree project which focuses on the lack of safe drinking water in a small village known as Macedonia in the Amazon basin in Colombia. The inhabitants of the village are 850 to the number and have never had access to safe drinking water. To solve this problem a system has been built where the rainwater is harvested in a pond and also from a church roof</p><p>During the dry season the rainwater in the pond is harvested and pumped into sedimentation tanks. Thereafter, the water is led into the sand filtration tanks. While during the rain season, the rainwater is harvested from a church roof which is situated at highest level in Macedonia. The water is stored in a cistern and then it is led into sand filtration tanks via pipes. This means that the pond water and rainwater are never mixed before entering the filtration tanks.</p><p>The sand filtration tanks contain about 1000 mm thick layer of sand and under it, a layer of gravel which is placed in the bottom of the tank. It takes a while for the water to be filtered through the sand filtration tank. Afterwards, it is led into the final tank, where the drinking water is stored ready to be used.</p><p>The method of using slow sand filtration (SSF) is suitable for small scale-projects and therefore for this project a good idea for making drinking water. SSF requires no mechanical power or replaceable parts, this is why the technique is good for purifying water in developing and isolated areas.</p><p>The result of the system is water with satisfied quality running through pipes and taps, ready to be consumed.</p><p> </p><p> </p><p> </p><p> </p>

In recent years, the increasing awareness of scarcity of water resources, indications of likely climate variability, and the increasing pressure to use available fresh water resources more efficiently have together reinforced the need to look at infrastructure solutions with due regard to environmental considerations and social impacts, present and future. There is a vital need to apply an integrated approach to catchment management to implement sustainable solutions to resolve issues such as water supply and sewerage, drainage and river flooding. Many potentials solutions are available to control water demand and manage flood problems. Greywater recycling and rainwater harvesting are novel technologies. However, their catchment scale impacts on hydraulic and hydrological flows are poorly understood. The research aim is to identify the hydrologic and hydraulic impacts of scaling up such technologies at catchment scale. For this particular study, a computer simulation model will be used to evaluate how increasing urbanisation, climate change and the implementation of greywater recycling and rainwater harvesting may alter the water balance within a representative catchment. To achieve these aims data from the Carrickmines catchment in Ireland have been collected; a simulation model has been adapted to carry out the study, the model has been calibrated and validated, results have been analysed, and finally, a sensitivity analysis has been carried out. The results show that rainwater harvesting systems are comparatively more effective than greywater recycling techniques in reducing flood frequency and intensity. Under five year return period rainfall events, the implementation of rainwater harvesting at any scale and number of units is a useful technique to control river flow and floods. However, the study also shows that under extreme conditions the efficiency of rainwater harvesting systems decreases. The study concludes that implementing the two technologies within a single catchment is not a solution to several forms of hydrological problem. The study shows that implementing rainwater harvesting or re-use technologies are a very useful way to protect local freshwater reserves and therefore conserve our environment.

Made available in DSpace on 2015-05-14T12:09:09Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3136257 bytes, checksum: 455dacf19263b72ad2227f133783a225 (MD5) Previous issue date: 2012-06-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The expectation of drinking water shortage for the next years has been a motivating factor to search for alternatives to supply the demand of future generations, to promote rational use of water and to reduce its waste. Once water is directly linked to people s maintenance and quality of life, also jeopardizing all living species in our planet, it is imperative that the entire civil, business and industrial society as well the government and its public institutions seek mechanism to preserve it. This research aimed at proposing a system of rainwater usage for Campina Grande campus of the Federal Institute of Education, Science and Technology of Paraíba IFPB and analyzing the economic viability of its establishment. The general goal was to evaluate the possibility of rainwater usage for non-drinking use in flush toilets, car wash and garden watering as sustainable mechanism of water rational usage in order to minimize drinking water waste, reduce costs of water bought by the institution and to comply with the sustainability criteria required by the Normative Instruction number 01/2010 of the Planning, Budget and Management Ministry MPOG. The methodological approach was based on descriptive and exploratory parameters, with data obtained in loco by means of photographic and documental registers of the mentioned IFPB campus. In order to develop this study, data was collected referring to supply of rainwater in the region, and the survey of annual water consumption in the cited campus, the estimate of non-drinking water demand and the measurement of the storage reservoir were accomplished. Economic analysis of the investment was done by financial mathematical tools, and for a 787 m3 reservoir, the cost involved of R$ 180.447,44, the benefit/cost ratio of 2,52, the payback period of 9,83 years and the net present value of R$ 274.701,45 were found. Therefore, the economic viability of the rainwater harvesting system implementation was proved and it showed to be attractive, especially when it requires a very high demand of water with less noble purposes, as it is the case. The proposed system allowed the storage of rainwater which meets a demand of 94% of non-drinking consumption of the mentioned campus. This will provide meaningful saving of water acquired from the Water Company of Paraíba CAGEPA. / A expectativa de escassez de água potável para os próximos anos tem sido fator motivador de busca de alternativas para suprir a demanda das futuras gerações, promover o uso racional da água e reduzir o seu desperdício. Visto que a água está diretamente ligada à manutenção e qualidade de vida da população, comprometendo também, toda espécie de vida no nosso planeta, é imperativo que toda a sociedade civil, empresarial, industrial, como também o Governo e suas Instituições Públicas, busquem mecanismos para preservá-la. O tema deste trabalho foi propor um sistema de aproveitamento de água de chuva para o Campus Campina Grande do Instituto Federal de Educação, Ciência e Tecnologia da Paraíba IFPB e analisar a viabilidade econômica de sua implantação. O objetivo geral foi avaliar a possibilidade do aproveitamento de águas de chuva para uso não potável em descargas de vasos sanitários, lavagens de veículos e rega de jardins, como mecanismo sustentável de uso racional da água a fim de minimizar o desperdício de água potável, reduzir os custos de água comprada pela instituição e cumprir com os critérios de sustentabilidade exigidos pela Instrução Normativa n° 01/2010 do Ministério do Planejamento, Orçamento e Gestão - MPOG. A abordagem metodológica escolhida e elaborada foi baseada nos parâmetros descritivos e exploratórios, com dados obtidos in loco através de registros fotográficos e documentais do referido campus do IFPB. Para desenvolver esse estudo foram coletados dados referentes à oferta de água de chuva na região, feito o levantamento do consumo anual de água no referido campus, bem como a estimativa das demandas de água não potável e o dimensionamento do reservatório de armazenamento. Em seguida, foi realizada a análise econômica do investimento por meio de ferramentas da matemática financeira, que apresentou para um reservatório de capacidade de 787 m³, custos de investimento de R$ 180.447,44, relação Benefício/Custo igual a 2,52, o Período de Retorno de Capital de 9,83 anos e Valor Presente Líquido de R$ 274.701,45. Dessa forma foi comprovada, a viabilidade econômica da implantação do sistema de aproveitamento de água de chuva, que mostrou ser atrativo, principalmente quando se requer grandes demandas de água para fins menos nobres, como é o caso. O sistema proposto permite obter um volume de água armazenada em reservatório proveniente das chuvas da região, que atende a uma demanda de 94 % do consumo não potável do referido campus, o que proporcionará uma economia significativa de água comprada mensalmente à Companhia de Água da Paraíba - CAGEPA.

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.

Thesis (MSc .(Agronomy)) -- University of Limpopo, 2015 / The changes in climate, especially poor rainfall patterns and distributions are key issues posing major agricultural challenges for food security and threaten the rural livelihoods of many communities in the Limpopo Province. Rainfall (P) is low and limited. These limited P is mostly lost through runoff and evaporation, which result in low soil moisture availability and possible crop failure. Therefore, techniques that reduce these water losses are important for improving dryland crop production and rainwater productivity (RWP). The objectives of this study were to determine the potential and effectiveness of rainwater harvesting and conservation techniques (RWH&CT’s) to conserve and improve plant available water (PAW) for dryland maize production and also determine the efficiency of the RWH&CT’s to improve dryland maize yield and RWP compared to conventional tillage (CON). The study was conducted over a period of two growing seasons (2008/09; 2009/10) using maize as indicator crop at the Towoomba Research Station of the Limpopo Department of Agriculture in the Limpopo Province of South Africa, on an Arcadia ecotope. The experiment was laid out in a randomized complete block design, with four replications and five treatments. The five treatments used in the study were; conventional tillage (CON), No-till (NT), In-field rainwater harvesting (IRWH), Mechanized basins (MB) and Daling plough (DAL). The IRWH and DL were classified as rainwater harvesting techniques (RWHT’s), whilst MB and NT were classified as water conservation techniques. Two access tubes were installed at each treatment to measure the soil water content (SWC) at four different soil depths of 150, 450, 750 and 1050 mm using the neutron water meter. The data collected included climatic data, soil and plant parameters. The data were subjected to analysis of variance through NCSS 2000 Statistical System for Windows and GENSTAT 14th edition. Mean separation tests were computed using Fisher's protected least significant difference test. The SWC of IRWH, DAL and MB were about 510 and 490 mm higher compared to CON and NT treatment during the 2008/09 and 2009/10 seasons, respectively. The PAWT of the IRWH, MB and DAL was significantly different from the CON treatment during the 2008/09 season. For both seasons the biomass yield of the IRWH treatment was significantly different from the NT treatment, producing 23 and 50% more biomass in the 2008/09 and 2009/10 growing seasons, respectively. The grain yield under IRWH was significantly different from the NT treatment during both 2008/09 and 2009/10 seasons. The highest maize grain yield of IRWH was achieved during the 2009/10 season with 56% higher grain yield than the NT treatment. RWP from various RWHT’s were significantly different from the NT treatment. These results indicate that IRWH and DAL were 12 and 2% more effective in converting rainwater into harvestable grain yield than the CON treatment. R2 values of 68.6 and 78.4% for SWC and transpiration (Ev) were obtained when correlated with maize grain yield respectively. This indicates the importance of moisture conservation for improved dryland maize production under low P areas. Therefore, the use of appropriate RWHT’s by smallscale farmers maybe crucial to improve dryland maize production. IRWH outperformed all other treatments in terms of the soil parameters and plant parameter measured during the period of this study. Therefore, these results suggest IRWH has potential of sustaining maize yields under low rainfall conditions. Key words: Rainwater harvesting, conservation techniques, ecotope, rainwater productivity, maize yield, precipitation use efficiency.

One of the biggest upcoming challenges to the international community is the problem of a changing climate. The earth’s surface temperature is rising and associated impacts on physical and biological systems are increasingly being observed. Science tells us that climate change will bring about gradual changes, such as sea level rise, and shifts of climate zones due to increased temperatures and changes in precipitation patterns. A changing climate affects the entire world but will strike hardest against the poorest as they are the ones most dependent on agriculture which is a sector that is very vulnerable to changes in temperature and precipitation patterns. One region that will be especially vulnerable and has experienced the problems of shifting climate zones before is the Sahel region that borders to the south end of the Sahara desert where problems of desertification have occurred before. This region will in large extent be affected if the Intergovernmental Panel on Climate Change’s (IPCC) predictions of a rising temperature will become a reality. This is one of the reasons why I have chosen Burkina Faso, situated in the south end of the Sahel region, as the objective for my MFS. The question of rising temperatures will be especially important here as the region is very sensitive to differences in temperature. A crucial topic in this part of the world as well as the topic of this study is the process of adapting to the new climatic situation.

India is a country with progressing technical and economical development, but the development is not evenly distributed. Farmers in the Indian rural areas are struggling. There are worries that climate changes could have a negative impact on agriculture. This study was performed in Kancheepuram with support from the non-governmental organization Hand in Hand. The aims of this study were to analyze effects on agriculture due to watershed management in a village and to describe the crop patterns in a village and compare the yield with a village without watershed management. Data was collected by interviewing farmers in the villages Arapedu and Tenpakkam. In Arapedu watershed management was applied and in Tenpakkam it was not. Data collected by Hand in Hand on precipitation, village records, well inventory and maps were analyzed. The water level in the wells increased in most wells between 2007 and 2008, but due to short data series it was not possible to affirm if this was due to the watershed management or increased rainfall in the early months of 2008 compared to 2007. No evidence of change in precipitation in the area was observed. Only precipitation data was analyzed since other climate data was absent. Hand in Hand was working within a broad spectrum in the village. Apart from the watershed project they are working with empowerment of women´s situation, self-help groups, microfinance and against child labor. This study period was too short to confirm effects of watershed management. However this study can be used as a baseline study for future evaluations. Key words: Rainwater harvesting, watershed management, Tamil Nadu

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20006号 / 農博第2190号 / 新制||農||1045(附属図書館) / 学位論文||H28||N5015(農学部図書室) / 33102 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 藤原 正幸, 教授 村上 章, 准教授 宇波 耕一 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Due to the combined effect of intense rainfall events together with the expected impact of climate change, this will put pressure on the existing and future infrastructure for storm water management. One of the challenges related to this is the combined sewer system which is still operating in large areas of many cities worldwide. In Stockholm, combined sewer represents around 50% of the total sewer pipe length. In a Combined sewer system, once the conveyed discharge exceeds the system capacity, the system overflows, which can result in a diverse range of health and environmental problems. The cause of overflow has been strongly linked to runoff from intense rainfall events. Therefore, a key proposal to overcome this problem is to disconnect runoff from hard surfaces. This research aims to investigate the impact of applying a rainwater harvesting (RWH) and reuse system to collect runoff water from roof surfaces in areas with combined sewer system. A simulation water balance model for a rooftop RWH system was developed and two reuse purposes were considered, which entails toilet flushing and garden irrigation within the property. The study area consists of one building block within Kungsholmen area in Stockholm. The obtained results indicate that applying such systems can reduce runoff to the sewer system. Toilet flushing reuse shows a higher reduction impact on sewer flow than the use for irrigation. Toilet flushing reuse reduces annual runoff volumes to sewer in a range of 49.5% - 93.4% while irrigation provided reduction in a range of 11.6% - 26.3%. Regarding number of times that overflow from the combined sewer system occurs, toilet flushing reuse demonstrated reduction of 40% - 100% while 20% to 60% was reduced by irrigation reuse. For overflow volume, a reduction rate of 11% to 100% was reached through toilet flushing in contrast to 9% to 43% reduction from irrigation reuse. 19% to 37% of toilet flushing water demand was covered by the tank, while arange of 48% to 100% was covered for irrigation demand. All these parameters were found to be sensitive to change in tank size where increasing the size result in higher flow reduction rates. When considering implementing a reuse system, it is important to consider the applicability of RWH and reuse within the specific property. In areas that are under development, either of the two reuses can be considered depending on local conditions. However, in already built up area it is difficult to introduce a system that requires significant adjustment to existing pipe networks, such as reuse systems for toilet flushing. Systems for outdoor irrigation are possible to implement in most situations. When it comes to tank size, the optimal size will depend on the intended reuse, the catchment area and the objective of the system. For example, if the main objective is to reduce potable water consumption, a smaller tank can be used compared to where the main objective is to reduce sewer overflow. Hence, when considering implementing a rainwater reuse systems, each project will need to consider the local conditions as well as the individual objectives when determining the optimal reuse purpose and tank size. A cost-benefit analysis should also be considered when determining the optimal tank size for the intended use.