Dissertations / Theses on the topic 'Rainwater harvesting system'

Thesis (MEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: The focus of the study is to theoretically assess tank-water demand and employ methods to establish the actual tank-water demand at selected houses in a case study area. This study also examines the influence of domestic rainwater harvesting systems when used in combination with a municipal water distribution system. The case study comprises of 410 low cost housing units in the Western Cape. The system demand patterns of low cost housing units are uncharacteristic, when compared with suburban system demand patterns, and cannot be defined by traditional models. Similarly, the use of rainwater harvesting systems in these areas follows an unconventional routine that is yet to be defined. A stochastic end-use model for water demand is developed which produces temporal profiles for water supplied from both sources, namely the water distribution system and the rainwater harvesting system. The model approximates a daily system and tank-water demand pattern for a single domestic household, using @RISK software. The demand estimation methodology is clarified through application on a particular case study site where harvested rainwater is frequently utilized. Estimates of the parameter values are based on consumer surveys and previous studies on the case study area, where the household size was defined in the form of a probability distribution. The results confirm the atypical system demand patterns in low cost housing units units. Although two clear peaks exist in the morning and in the evening, a relatively constant average flow is present throughout the day. A sensitivity analysis of all the model parameters verified that the household size has the most substantial influence on the tank-water demand pattern. The system and tank-water demand patterns were compared to published average daily water demand guidelines, which confirmed that increased water savings could be achieved when the rainwater source is accessible inside the household with minimal effort. The stochastic demand profiles derived as part of this research agree with the metered system demand in the same area. The results of this study could be incorporated into the future development of national standards.
AFRIKAANSE OPSOMMING: Die fokus van die studie is om die tenkwater-aanvraag teoreties te ontleed en metodes in werking te stel om die werklike tenkwater-aanvraag vas te stel by geselekteerde huise in ‘n gevallestudie area. Hierdie studie ondersoek ook die invloed van plaaslike reënwater-herwinningstelsels wanneer dit gebruik word in kombinasie met ‘n munisipale waterverspreidingstelsel. Die gevallestudie bestaan uit 410 laekoste behuisingseenhede in die Wes-Kaap. Die stelsel-aanvraagpatrone van laekoste behuisingseenhede is verskillend wanneer dit met voorstedelike stelsel-aanvraagpatrone vergelyk word en kan nie gedefinieer word deur tradisionele modelle nie. Soortgelyk volg die gebruik van reënwater-herwinningstelsels in hierdie areas ‘n onkonvensionele roetine. ‘n Stogastiese eindgebruikmodel vir water-aanvraag is ontwikkel, wat tydelike profiele genereer vir water wat van beide bronne verskaf word, naamlik die waterverspreidingstelsel en die reënwater-herwinningstelsel. Die model bepaal by benadering ‘n daaglikse stelsel- en tenkwater-aanvraagpatroon vir ‘n enkele plaaslike huishouding, deur @RISK sagteware. Die aanvraag-beramingstegnieke word verduidelik deur toepassing op ‘n spesifieke gevallestudie, waar herwinde reënwater gereeld gebruik word. Die parameter waardeberamings is gebaseer op verbruikers-opnames en vorige studies oor die gevallestudie-gebied, waar die grootte van die huishoudings bepaal was in die vorm van 'n waarskynlikheidsverspreiding. Die resultate bevestig die atipiese stesel aanvraagpatrone in laekoste behuisingseenhede eenhede. Alhoewel twee duidelike pieke in die oggend en die aand voorkom, is ‘n relatiewe konstante vloei dwarsdeur die dag teenwoordig. ‘n Sensitiwiteitsanalise van al die modelparameters bevestig dat die grootte van die huishouding die grootste beduidende invloed op tenkwater- aanvraagpatrone het. Die stelsel- en tenkwater-aanvraagpatrone was vergelyk met gepubliseerde gemiddelde daaglikse water-aanvraag riglyne wat bevestig dat meer waterbesparings bereik kan word waar die reënwaterbron binne die huishouding beskikbaar is met minimale moeite. Die stogastiese aanvraagprofiele, wat as deel van hierdie navorsing afgelei was, stem saam met die gemeterde stelsel-aanvraagpatroon van dieselfde area. Die resultate van hierdie studie kan in die toekomstige ontwikkeling van nasionale standaarde opgeneem word.

En esta dissertación se desarrolló un modelo para evaluar técnica, económica y ambientalmente sistemas de recogida de agua de lluvia para aprovechamiento doméstico urbano. Se analizaron diferentes tipologías de vivienda (vivienda tipo casa y vivienda tipo apartamento) y diferentes sistemas (vivienda unifamiliar, edificio de apartamentos y barrio). Se encontraron los escenarios de viabilidad económica y ambiental y se desarrollaron submodelos específicos para la evaluación directa en un amplio rango de condiciones climáticas, precios y calidad del agua para sistemas de diferentes escalas urbanas. La disertación esta preparada en cinco partes y ocho capítulos. Parte I. INTRODUCCION y MARCO METODOLOGICO APLICADO La Parte I se divide en dos capítulos. El Capítulo 1 introduce el trabajo en general y presenta un marco integral de los recursos hídricos y su importancia en las ciudades. En este capítulo se incluye la oferta y la renovabilidad de los recursos hídricos en algunos países del mundo, y las demandas de agua urbanas y las tendencias de crecimiento urbano futuro. También se muestra una relación entre consumo doméstico de agua de red y la relación entre agua y energía. Por último se exponen, la justificación y los objetivos que llevaron al desarrollo de esta tesis. El Capítulo 2 presenta la metodología general que se desarrolló, dando un especial énfasis en la modelización de sistemas, análisis económico y de evaluación ambiental. Además, en este capítulo se incluyen los sistemas analizados y estudios de casos incluidos en la investigación, así como la validación realizada en el principal modelo desarrollado. Parte II. MODELADO DE LOS SISTEMAS DE RECOGIDA DE AGUA DE LLUVIA La Parte II incluye el Capítulo 3. Este capítulo presenta en detalle el desarrollo de un modelo de simulación de los sistemas de recogida de agua de lluvia y su evaluación comparativa con otros softwares existentes. Este software se llama Plugrisost como un acrónimo de pluviales, grises y la sostenibilidad. Además, en el capítulo se describen los factores determinantes que condujeron a su creación y las nuevas características incluidas para facilitar la evaluación integral de recogida de aguas pluviales. Parte III. ASPECTOS SOCIALES, OFERTA POTENCIAL Y LOS BENEFICIOS AMBIENTALES DE AGUA DEL LLUVIA EN ZONAS URBANAS La Parte III se compone de dos capítulos. El Capítulo 4 presenta un estudio sobre el potencial de captación de aguas pluviales en los países en vías de desarrollo, teniendo como estudio de caso a Colombia. Además, este estudio muestra que algunos aspectos socio-económicos pueden influir en el potencial para captar agua de lluvia. El Capítulo 5 analiza los impactos ambientales potenciales en el contexto de los nuevos barrios en los países en desarrollo, tomando como estudio de caso a Colombia. Este capítulo presenta los modelos que se pueden aplicar en las evaluaciones ambientales rápidas en estos escenarios. Parte IV. PRINCIPALES FACTORES EN EL ANÁLISIS ECONÓMICO Y MEDIOAMBIENTAL La Parte IV se compone de dos capítulos. El Capítulo 6 analiza la viabilidad económica y financiera y el impacto ambiental de los sistemas de RWH tomando como estudio de caso a España. Se desarrollan los modelos para evaluar económica y ambientalmente estos sistemas. Además, se exponen los factores determinantes que afectan a estas evaluaciones. El Capítulo 7 se centra en analizar el efecto potencial de la calidad del agua de red en el análisis económico y ambiental de los sistemas de recogida de agua de lluvia. La dureza del agua es el parámetro analizado en un amplio intervalo de condiciones urbanas y sistemas diferentes. Parte V. CONCLUSIONES Y PRÓXIMOS PASOS La Parte IV se compone de un capítulo. El Capítulo 8 presenta las conclusiones generales de la tesis de conformidad con los objetivos fijados. También se incluye un marco de ideas para futuras investigaciones que puedan seguir desarrollándose en los sistemas de recogida de agua de lluvia.
This dissertation developed a model to evaluate technical, economic and environmental aspects of rainwater harvesting systems for domestic urban use. Different types of housing (semi-detached house and apartment house) and different systems (one single-house, apartment building and neighborhood) were analyzed. Then, scenarios of economic and environmental viability were found and specific sub-models were developed for use in the direct evaluation of a wide range of climatic conditions, prices and quality of mains water in different urban scales. The dissertation is prepared into five main parts and eight chapters. Part I. INTRODUCTION and METHODOLOGICAL FRAMEWORK APPLIED Part I is divided into two chapters. Chapter 1 introduces the general work presenting a comprehensive framework of water resources and their importance in the cities. This chapter includes the supply and renewability of water resources in some countries of the world, and the urban water demands and trends of future urban growth. Also it is shown a relationship of domestic consumption of mains water and the relationship between water and energy. Finally, the motivations and the objectives that led to this dissertation are presented. Chapter 2 presents the general methodology that was developed, giving a special emphasis on system modelling, economic analysis and environmental assessment. In addition, this chapter includes the systems and case studies included in the research and validation carried on the main model developed. Part II. MODELLING RAINWATER HARVESTING SYSTEMS Part II includes the Chapter 3. This chapter presents in detail the development of a simulation model of RWH systems, and its benchmarking against other existing softwares. This software is called Plugrisost as an acronym for pluvials, grey and sustainability. In addition, the chapter describes the determinants factors that led to its creation and the new features included to facilitate the comprehensive assessment of rainwater harvesting. Part III. SOCIAL ASPECTS, POTENTIAL SUPPLY AND ENVIRONMENTAL BENEFITS OF RAINWATER IN URBAN AREAS Part III is composed of two chapters. Chapter 4 presents a study of the potential of rainwater harvesting in countries in process of development taking as a case study in Colombia. Additionally, this study shows that some socioeconomic aspects may influence the potential to capture rainwater. Chapter 5 discusses the potential environmental impacts in the context of new neighborhoods in developing countries, taking as a case study in Colombia. This chapter presents models that can be applied in rapid environmental assessments in these scenarios. Part IV. MAIN FACTORS IN THE ECONOMIC AND ENVIRONMENTAL ANALYSIS Part IV is composed of two chapters. Chapter 6 analyzes the economic and financial viability and environmental impact of RWH systems taking as a case study in Spain. Models to asses economically and environmentally these systems are developed. Also, the determinants that affect these assessments are exposed. Chapter 7 is focused on analyzing the potential effect of water network quality in the economic and environmental analysis of RWH systems. Hardness of the water is the parameter analyzed over a broad range of urban conditions and different systems. Part V. CONCLUSIONS AND NEXT STEPS Part IV is composed of one chapter. Chapter 8 presents the overall findings of the dissertation in accordance with the stated objectives. It is also included future researches that may continue to be developed in RWH systems.

 

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

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.

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.

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.

The result of the system is water with satisfied quality running through pipes and taps, ready to be consumed.

 

 

 

 

Att samla in regnvatten för att använda till olika syften har under de senaste åren blivit allt vanligare i flera länder. Denna metod är fördelaktig ur flera miljömässiga och samhällsekonomiska aspekter då den bidrar till minskad dricksvattenförbrukning och förbättrad dagvattenhantering. I Sverige är tekniken relativt obeprövad men flera stora byggnader där det ska implementeras är nu under byggnation. En av dessa är Celsiushuset i Uppsala där regnvatten ska samlas in på taket för att användas till toalettspolning. I dagsläget finns bristfällig kunskap om sådana system inom sektorn för samhällsbyggnad. Syftet med examensarbetet var dels att undersöka effektiviteten (andelen av toalettspolningen som sker med regnvatten) hos Celsiushusets system och utifrån det föreslå en lämplig magasinstorlek, och dels att rekommendera vattenreningsmetoder för att inte mikrobiell tillväxt eller algtillväxt ska uppstå eller att regnvattnet ska bli missfärgat eller orsaka luktproblematik.  Effektiviteten undersöktes, tillsammans med relaterade parametrar såsom nederbörd, avrinning och insamlad nederbördsmängd, genom att utföra dagliga simuleringar för tre olika femårsperioder. Tidsperioderna motsvarade en nederbördsfattig period, en genomsnittsperiod och en nederbördsrik period mellan åren 1961-2017 och simuleringarna utgick från dygnsvärden för nederbörd och temperatur. Även förenklade kostnadsberäkningar utfördes för att undersöka kostnadens variation med varierande magasinstorlek. Reningsmetoderna rekommenderades utifrån en litteraturstudie samt beräkningar av takavrinningens föroreningsbelastning som utfördes med StormTac. För den planerade magasinstorleken på 50 m3 är systemets effektivitet störst under sommaren och hösten (60-100 % ett genomsnittsår) och lägst under årets första månader (30-40 % ett genomsnittsår). Den sammantagna effektiviteten för den planerade storleken är för den nederbördsfattiga perioden 40 %, för genomsnittsperioden 51 % och för den nederbördsrika perioden 56 %. En magasinstorlek på mellan 50 m3 och 75 m3 är lämplig för att uppnå relativt hög genomsnittlig effektivitet och årlig insamlad nederbördsmängd, utan att medföra alltför höga kostnader. Magasinet bör inte vara mindre än 50 m3 och en volym närmare 75 m3 vore fördelaktigt för den insamlade nederbördsmängden. Reningsmetoderna som rekommenderas för systemet är takbrunnar med kupolsil, avskiljning av det första flödet, sedimentering i sandfångsbrunnar och i magasinet samt ett snabbt sandfilter och UV-behandling.
In recent years, there has been an increased usage of rainwater harvesting globally. The technology reduces drinking water consumption and improves stormwater management. In Sweden, the implementation of rainwater harvesting is still at an early stage but several systems are now under construction. One of them is in Celsiushuset in Uppsala where rainwater will be used for toilet flushing. One aim of the project was to calculate the efficiency (the ratio between the volume of used rainwater and the water demand for toilet flushing) of the system. Based on the efficiency and economic calculations, an appropiate storage tank size was to be identified. An additional aim was to recommend water treatment methods that would prevent color or odour in water in the toilets and also prevent microbe and algae growth. The efficiency, along with other parameters, was examined with simulations for three periods between 1961-2017 with different precipitation amounts. Also, a simplified calculation of the systems' costs depending on tank size was carried out. The recommendation of treatment methods was made based on a literature review combined with a calculation of the roof runoff quality, which was performed in StormTac. For a tank size of 50 m3, the highest efficiency of the system is obtained during summer and autumn and varies between 60 % and 100 %. The mean efficiency for the different periods has a higher value with increased precipitation amount and the efficiency is 40 %, 51 % and 56 %, respectively. An appropiate size of the rainwater storage tank would be between 50 m3 and 75 m3. The recommended treatment methods include strainers on the roof, a first flush diverter, sedimentation, a rapid sand filter and UV treatment.

Este trabalho foi realizado no âmbito do conceito de aproveitamento de água pluvial para rega em estruturas desportivas, tendo como caso de estudo o Estádio da Luz – Sport Lisboa e Benfica. Consiste, na avaliação da possibilidade de utilização/benefício associado à utilização da água pluvial para a rega do relvado do caso de estudo, em função das características da estrutura, dos registos pluviométricos e da qualidade da água pluvial.
This work was performed under the concept of harnessing rainwater for watering sports structures, taking as case study the Benfica Stadium - Sport Lisboa e Benfica. It consists in the evaluation of possibility of use / benefits associated to the use of rainwater for irrigation the lawn in the case study, according to the characteristics of the structure, of rainfall records and quality of rainwater.

Vattenbesparing och alternativa lösningar för att tillgodose vattenbehovet har blivit mer aktuellt de senaste åren med torka. Regnvatteninsamling för hushållsanvändning används redan på många platser runtom i världen men är begränsad i Sverige idag. Syftet är att dels undersöka en lämplig dimensionering av ett system för regnvatteninsamling för hushåll i Jälåsa och att identifiera olika drivkrafter och hinder. Metoden i denna studie har varit dels massbalans- och effektivitetsberäkningar för att se hur mycket regnvatten som kan samlas in och dels intervjuer med två teknikleverantörer och fem kommuner för att utvärdera den juridiska, sociala och ekonomiska potentialen. Resultatet visade att tankstorlek på mellan 1000 och 4000 liter är rimligt för hushållsanvändning till toalett eller toalett och tvättmaskin och ger en effektivitet (procent av vattenbehovet som täcks av regnvatten) på mellan 83,6 % och 96,0 %. Vilken storlek som är mest lämplig beror på faktorer såsom vad regnvattnet används till, takyta, antal personer i hushållet och om first-flushbortledning används. Beräkningar visar att ungefär 19-29 % av den totala dricksvattenförbrukningen skulle kunna sparas i Järlåsa, vilket motsvarar ungefär 4 400 till 6 700 kubikmeter dricksvatten per år. Resultatet visar även att torrperioder då tanken är tom blir kortare med en större tankstorlek och det finns tydliga skillnader i volym vatten i tanken mellan olika nederbördsrika år. Enligt kommuner ansågs potentialen för regnvatteninsamling vara störst för bevattning i dagsläget men att de även var positivt inställda till annan användning såsom toalettspolning och tvättmaskin. Identifierade hinder var oro kring kontamination av dricksvatten, brist på ekonomisk lönsamhet till följd av låga dricksvattenpriser i Sverige och behov av förtydligande av krav och vilka risker som finns med regnvatteninsamling. Idag är potentialen och motivationen som störst för de som har dålig tillgång på vatten och en ökad miljömässig medvetenhet skulle kunna öka implementeringen av regnvatteninsamling i Sverige. Slutsatsen är att det finns potential för regnvatteninsamling men att det fortfarande krävs viss utveckling och mer kunskap om regnvatteninsamling under svenska förhållanden.
Water saving and alternative solutions to supply drinking water have become more important due to several consecutive droughts in recent years in Sweden. Rainwater harvesting for households is already being used in many places around the world but still has limited application in Sweden. The purpose with this study is to investigate a suitable sizing of a rainwater harvesting system in Järlåsa and to identify drivers and obstacles for implementation. The methods used in this study were firstly calculations based on mass balance and efficiency estimates and secondly interviews with two technology providers and five municipalities. The results showed that a tank size between 1000 and 4000 liters would be suitable for the purpose of supplying water for flushing toilets and for washing machines and the efficiency (percentage of water demand being met by rainwater) would be between 83,6% and 96,0%. What size tank is recommended depends on factors such as what rainwater is used for, roof area, number of people in household and whether first-flush is diverted. Results show that around 19-29%, around 4 400 to 6 700 cubic meters per year, of the total potable water consumption could be saved in Järlåsa every year using rainwater harvesting. The results also show that the dry periods, when the tank was empty, become shorter with a larger tank size and that there are distinct differences in the volume rainwater in the tank between years with varying precipitation. According to municipalities the potential was highest for irrigation purposes today but there was also potential for use in household for flushing toilets and supplying washing machines. The identified obstacles were concern regarding contamination of the drinking water supply, lack of economic profitability as a consequence of low water prices and the need for clarification of requirements and risks with rainwater harvesting. Today the potential and motivation is highest for those with an insufficient water supply and an increase in the environmental awareness could possibly enhance implementation further. The conclusion is that there is potential for rainwater harvesting but that there still is a need for some development and more knowledge regarding rainwater harvesting under Swedish conditions.

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The objective of this study was to size the reservoir for rainwater harvesting system in the Campos Gerais of Paraná according to the methodologies proposed by the ABNT (2007), considering the impacts of climate change projected until the end of the 21st century on the fifth report of the IPCC. On this paper, the methodologies for calculation of final volume of rainwater reservoir proposed by ABNT (2007) were used, as well the historical series of rainfall data and those projected for two possible climatic scenarios were used. Through the PGECLIMA_R tool, it was possible to project the precipitation levels predicted in the best and the worst climatic scenario by the end of the century, in order to size the reservoir and analyze the impacts caused by climate change under the final volume of the rainwater reservoir. It was concluded that the designer should take into account the expected climate changes for the design of storage reservoirs and the use of rainwater, since these presented large volume variations according to each applied methodology and for each simulated scenario. When designing future precipitation data, the PGECLIMA_R software presented itself as an important tool to be used in the area of civil construction, urban and development planning.
O objetivo deste estudo foi dimensionar o reservatório para águas pluviais para a Região dos Campos Gerais do Paraná de acordo com as metodologias propostas pela ABNT (2007), considerando para tanto os impactos das alterações climáticas projetadas até o final do século XXI do quinto relatório do IPCC. Para realização deste trabalho foram utilizadas as metodologias de cálculo de volume final de reservatório de água pluvial propostas pela ABNT (2007), série histórica de dados pluviométricos assim como os projetados para dois possíveis cenários climáticos. Através da ferramenta PGECLIMA_R foi possível projetar os níveis de precipitação previstos no melhor e no pior cenário climático para o final do século, e desta forma dimensionar o reservatório e analisar os impactos causados pelas alterações climáticas sob o volume final do reservatório para águas pluviais. Concluiu-se que os métodos de dimensionamento estudados possuem grande sensibilidade quanto às alterações climáticas, sendo assim o projetista deve levar em consideração as alterações climáticas previstas para proceder com o dimensionamento de reservatórios de armazenamento e utilização das águas pluviais, uma vez que estes apresentaram grandes variações de volume de acordo com cada metodologia aplicada e para cada cenário simulado. Ao projetar dados de precipitação futuros, o software PGECLIMA_R apresentou-se como uma importante ferramenta a ser utilizada na área da construção civil, de planejamento e desenvolvimento urbano.

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O objetivo deste estudo foi dimensionar o reservatório para águas pluviais para a Região dos Campos Gerais do Paraná de acordo com as metodologias propostas pela Associação Brasileira de Normas Técnicas (ABNT), considerando para tanto os impactos das alterações climáticas projetadas até o final do século XXI do quinto relatório do Painel Intergovernamental de Mudanças Climáticas. Para realização deste trabalho foram utilizadas as metodologias de cálculo de volume final de reservatório de água pluvial propostas pela ABNT, série histórica de dados pluviométricos assim como os projetados para dois possíveis cenários climáticos. Através da ferramenta PGECLIMA_R foi possível projetar os níveis de precipitação previstos no melhor e no pior cenário climático para o final do século, e desta forma dimensionar o reservatório e analisar os impactos causados pelas alterações climáticas sob o volume final do reservatório para águas pluviais. Concluiu-se que os métodos de dimensionamento estudados possuem grande sensibilidade quanto às alterações climáticas, sendo assim o projetista deve levar em consideração as alterações climáticas previstas para proceder com o dimensionamento de reservatórios de armazenamento e utilização das águas pluviais, uma vez que estes apresentaram grandes variações de volume de acordo com cada metodologia aplicada e para cada cenário simulado. Ao projetar dados de precipitação futuros, o software PGECLIMA_R apresentou-se como uma importante ferramenta a ser utilizada na área da construção civil, de planejamento e desenvolvimento urbano.
The objective of this study was to size the reservoir for rainwater harvesting system in the Campos Gerais of Paraná according to the methodologies proposed by the ABNT (2007), considering the impacts of climate change projected until the end of the 21st century on the fifth report of the Intergovernmental Panel on Climate Change. On this paper, the methodologies for calculation of final volume of rainwater reservoir proposed by ABNT (2007) were used, as well the historical series of rainfall data and those projected for two possible climatic scenarios were used. Through the PGECLIMA_R tool, it was possible to project the precipitation levels predicted in the best and the worst climatic scenario by the end of the century, in order to size the reservoir and analyze the impacts caused by climate change under the final volume of the rainwater reservoir. It was concluded that the designer should take into account the expected climate changes for the design of storage reservoirs and the use of rainwater, since these presented large volume variations according to each applied methodology and for each simulated scenario. When designing future precipitation data, the PGECLIMA_R software presented itself as an important tool to be used in the area of civil construction, urban and development planning.

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The potable water scarcity afflicts the begging of the 21st Century, being today, one of the main worries of the manhood. This way, it becomes necessary to reduce the per capita consumption. From the actions that promote the racional use of water, the technological ones seems to be , in the most of the cases, the most recomended to reduce the consumption without being necessary radical changes of the users. One of these technologies is the rainwater harvesting. This one erges as an action of good perspectives since it subistitutes the use of potable water in activities where it is not necessary a good quality water, younder, it will reduce the amount of stormwater in the public drainage net, working as a non-structural action of urban drainage. The lack of kwondlege as well a the real advantages that a rainwater system can bring to a builind, is the points to find out about this issue.. At this paper, it seeked to clear this techonolgy up with the study of national and international examples . It also seeked the cistern sizing, getting the best results to technical and economical issues, as well, as procedures to design and to mantain the devices that make part of the system used in this study. Besides that, it studied the changes that would be necessary to build the system, and the possibles changes at the work routine of the construction company. It also studied the financial feasibility of the investiment of this interprisement, checking the real economical advantages that can be get. It is waited that this research contributes to the development of this techonology, contributing to Racional use of water in residential tall buildings.
A escassez de água potável atormenta o início do Século XXI, sendo hoje uma das principais preocupações da humanidade neste século que começa. Dessa forma, surge a necessidade de redução do consumo per capita. Dentre as ações que promovem o uso racional da água, as tecnológicas parecem ser , na maioria dos casos, as mais recomendadas para reduzir o consumo sem que seja necessário mudanças radicais nos hábitos dos usuários. Entre estas, o aproveitamento de água pluvial surge como uma ação de boas perspectivas, pois substitui o uso de água potável onde a qualidade desta não é necessária e, a retirada desta diminuirá a quantidade de volume de água pluvial lançada na rede pública de drenagem, funcionando como uma medida não-estrutural de drenagem urbana. A falta de conhecimento técnico bem como das reais vantagens que um sistema de aproveitamento de água pluvial poderá trazer para uma edificação são as principais incógnitas desse assunto. Neste trabalho buscou-se clarear a tecnologia, com o estudo de diversos casos nacionais e internacionais. Também se buscou realizar o dimensionamento de forma mais correta e econômica, bem como listar procedimentos para elaboração e manutenção de todos os elementos constituintes do sistema utilizado no edifício objeto de estudo. Além disto, verificou-se as possíveis interferências nos processos construtivos, além de alterações das rotinas de trabalho da construtora, além do estudo da viabilidade financeira do empreendimento, verificando as reais vantagens da implantação do sistema neste caso. Espera-se que esse trabalho contribua para o desenvolvimento de uma tecnologia específica para o uso racional de água.

This diploma thesis is focused on a large-scale irrigation embedded in the urban landscape. The main goal is to find a new concept of the large-scale irrigation system using a minimum of added electrical energy. The system is aimed at rainwater harvesting and distribution in populated areas. Part of the work is the analysis of the zoning plan of the selected locality, the design of the entire system from the accumulation of collected water to the distribution of watering to the root zone of plants. In the practical part, the proposed distribution network is calculated according to the current known equations, and the calculation is finished with the choice of a suitable diameter of the pipeline network. In addition, the work suggests possible sites for new planting of plants.

El aprovechamiento de agua de lluvia, a pesar de ser una antigua técnica para recoger escorrentía para uso doméstico, agricultura y gestión ambiental, no tiene una amplia aplicación. Potencialmente, los sistemas de aprovechamiento de agua de lluvia (RWH) pueden jugar un papel clave en el abastecimiento de la demanda de agua urbana como una alternativa a las tecnologías convencionales de tratamiento de agua como son la desalinización y otras tecnologías costosas Esta tesis doctoral pretende encontrar las configuraciones de RWH más eficientes, primero cuantificando el consumo de recursos e impactos ambientales asociados con RWH en áreas urbanas, y, después, estudiando las diferentes configuraciones para abastecimiento doméstico considerando condiciones climáticas mediterráneas y desérticas. La investigación está motivada por el incremento en la necesidad de encontrar medidas correctoras y preventivas que ayuden a gestionar los problemas de abastecimiento de agua, especialmente considerando los efectos del cambio climático en el área mediterránea y los del abastecimiento de agua en las zonas áridas. En línea con este planteamiento, la hipótesis se basa en el hecho de que el agua pluvial es agua blanda y, por lo tanto, requiere menos detergente y aditivos suavizantes. De ahí que represente un sustituto ventajoso para el agua utilizada en lavandería, especialmente en lugares donde el agua de grifo presenta altos niveles de dureza, así como cuando la disponibilidad de agua es limitada. Para analizar las diferentes configuraciones de RWH, se aplicaron las siguientes metodologías: análisis de exergía y análisis de eficiencia exergética para determinar el consumo de recursos y eficiencia; análisis de ciclo de vida (LCA) para identificar los impactos ambientales; análisis de coste de ciclo de vida (LCC) para encontrar la viabilidad económica, y análisis envolvente de datos (DEA) para identificar la frontera de mejores-prácticas hacia la sostenibilidad. En general, los resultados evidencian que configuraciones en clúster son más eficientes en el uso de recursos que las individuales, en términos exergéticos y económicos. Se encontró que los impactos ambientales son inversamente proporcionales al incremento en el abastecimiento de agua de lluvia. Los escenarios de mejores prácticas son mayoritariamente dependientes al área de recogida. Asimismo, los ahorros en el consumo de aditivos de lavandería resultan en una mejor conducta ambiental y económica en zonas con alta dureza en agua de grifo.
Rainwater harvesting, though is an ancient technique to collect run-off rainwater for domestic water supply, agriculture and environmental management, it is not widely applied. Rainwater harvesting (RWH) systems could potentially play a key role in helping cities meet their water demand, as an alternative to conventional water treatment technologies such as desalination and other costly technologies. This doctoral thesis aims to find the most efficient configuration of RWH, first by quantifying the resource consumption and environmental impacts associated to RWH in urban areas and then studying different configurations for domestic water supply considering Mediterranean and desert climate conditions. The query is motivated by the increasing necessity to find preventive and corrective measures that help cope with water supply problems, especially considering climate change effects in the Mediterranean area and water supply problems in arid areas. Along with this, the hypothesis is based on the fact that rainwater is soft water, thus, requires less detergent and softener additives. Therefore, it represents an advantageous substitute for water used for laundry, especially where tap water presents high levels of water hardness and also whenever water availability is limited. To analyze the different RWH configurations, the following methodologies were applied: exergy analysis and exergetic efficiency analysis to find resource consumption and efficiency; life cycle assessment (LCA) to identify environmental impacts; life cycle costing (LCC) to find economic feasibility and; data envelopment analysis (DEA) to identify best-practice frontier towards sustainability. The results evidence that generally cluster configurations are more resource efficient than those in individual configurations, in exergetic and economic aspects. Environmental impacts were found to be inversely proportional to the increase in rainwater supply. Best-practice scenarios were found mostly dependent on the area of rainwater collection. Furthermore, savings from laundry additive consumption result in much improved economic and environmental performances in areas with hard tap water.

Dissertação apresentada para a obtenção do grau de Mestre em Engenharia do Ambiente, Perfil Engenharia Sanitária
With increasing pressure on the environment, particularly on water resources, due to outside forces such as climate change and population growth, water is nowadays a scarce and a valuable resource. With the need to find new alternatives, rainwater harvesting should be seen as an important strategy for better management of water resources, once it constitutes a free source of potable water. Rainwater harvesting systems, which already have a global implementation, are a recognised way for urban buildings to reduce their reliance on the public mains supply. Its applications are predominantly non-potable, namely toilet flushing and gardening. The aim of this report is to produce a comprehensive assessment of rainwater harvesting and its potential use all over the world, as well as the potential economical and environmental benefits. It is provided a description of all the rainwater harvesting system components, as well as water quality requirements according to the water final purpose. A case study is presented, which main object is to evaluate the feasibility of rainwater harvesting for gardening, applied to the University Campus of the Faculty of Sciences and Technology of Universidade Nova, Lisbon (FCT/UNL). A detailed characterization of the existing irrigation system on campus is provided, as well as its potential ability to collect rainwater. According to the supply and demand balance, several scenarios are presented in order to provide the necessary information for the decision-makers to evaluate the best solution for the desired application. For such, all the available information was analyzed, in order to determine the environmental, technical and economical viability of the project.

Changing weather patterns challenge societies globally and at multiple levels related to amongst others health, the environment, disaster management and mitigation. There is a need for greater flexibility and resilience, which in turn can be enabled through a transition towards increased sustainability in governance and infrastructure. Urban rainwater harvesting (URWH) is a term used in this paper to collect various approaches to the sustainable handling of rainwater in cities, a practice becoming increasingly common in some areas of the world. Global experiences can be useful learning opportunities in the planning, implementation and maintenance of sustainable urban rainwater harvesting in future smart cities. The aim of this thesis was to synthesize the factors of success of previous projects, in order to develop a framework tailored to the evaluation of projects concerned with rainwater harvesting. The review spans over 18 projects of different scale and design. The findings of the study show that successful URWH projects are: (1) found as part of urban renewal schemes; (2) successfully implemented by involved actors with open mindsets and flexible and collaborative working approaches; (3) maintained based on plans determined from the onset of the project, developed together with local actors, in order to involve the community and strengthen social inclusion. The revised evaluative framework, which is proposed as a result of the review, indicates general trends of success among the reviewed cases. To be fully operational, the framework should be further developed with additional URWH projects and revised thereafter.

Regnvatteninsamling för olika syften är väl utbrett världen över och har blivit allt mer populärt i takt med ett förändrat klimat. Idag används regnvatten på många håll till hushållsanvändning men intresset har även ökat inom industrisektorn. Syftet med examensarbetet var att undersöka möjligheterna för att samla in och lagra regnvatten samt ersätta dricksvatten i Sandvik AB:s kylsystem. Detta genomfördes dels genom att undersöka vilka tillstånd som krävs för att samla in regnvatten, dels genom att föreslå en magasinutformning, storlek samt lokalisering av denna utifrån flödesberäkningar och dels genom att undersöka hur temperaturen förändras hos regnvatten i ett magasin för att bedöma dess funktion som kylvatten. I studien har först flödesberäkningar med avseende på effektivitet (hur mycket regnvatten som kan ersätta dricksvatten) simulerats för en nederbördsfattig, nederbördsrik respektive genomsnittlig tidsperiod. Därefter konstruerades två modeller i HYDRUS-1D, vilka representerade regnvattenmagasin med omgivande jord vid en lodrätt och en horisontell värmetransport. Enligt studien bedöms verksamheten idag ha alla tillstånd som krävs och behöver inte några ytterligare tillstånd. Valet av magasin blev ett avsättningsmagasin under mark med hänsyn till lokala förutsättningar. Hela anläggningen kan maximalt nå en effektivitet på 44 % under ett nederbördsrikt år med dagens totala förbrukningsdata för dricksvatten i kylsystemet samt totala takytan. Jämförelsen mellan olika lokaliseringar inom anläggningen ledde till att Stålverk 64 föreslogs samt presenterades närmare och utifrån dess effektivitet valdes magasinstorleken 1500 m3 för de 30 000 m2 som Stålverk 64 har i takyta. Effektiviteten för Stålverk 64 blev under ett nederbördsrikt år 77 %, ett genomsnittligt år 64 % och under ett nederbördsfattigt år 54 %. Värmesimuleringarna visade på att det är ytterst få dygn om året som regnvatten som lagras i ett avsättningsmagasin riskerar att vara för varmt för att användas som kylvatten. Slutsatsen är att Sandvik AB har goda möjligheter att samla in regnvatten för att ersätta dricksvatten i kylsystemet men behöver utveckla större lagringsmöjligheter för att uppnå en ännu högre effektivitet.
Rainwater harvesting is used for different purposes all over the world and has increased in popularity in line with climate change. Rainwater is today widely used for households, but interest has also increased within the industrial sector. The aim with this thesis was to investigate rainwater harvesting as a substitute for the use of drinking water in Sandvik´s cooling system. This was examined by investigating legislation concerning rainwater harvesting, different designs and sizes of storage systems and locations that would be suitable for storing rainwater. Also, temperature changes in a rainwater storage system were examined to estimate rainwater´s use for cooling. Firstly, calculations of water flow were simulated with respect to efficiency (how much rainwater that can substitute for drinking water) for three periods with different amounts of precipitation. Secondly, two models were implemented in HYDRUS-1D to represent a storage system for rainwater with surrounding soil with a vertical and horizontal heat transport. The results indicate that the industry has required permits for rainwater harvesting. Taking local conditions into account, an underground storage was chosen to store the rainwater. The entire facility can have a maximum efficiency of 44 % during a year with a high amount of precipitation with the total roof area and today’s consumption of drinking water in the cooling system. A comparison between different locations within the facility resulted in a more specific presentation of Stålverk 64 with respect to its efficiency; 1500 m3 was proposed as the storage size for the roof area of 30 000 m2. The efficiency for Stålverk 64 varied between 54-77 % for years with different amounts of precipitation. Simulated heat transport demonstrated that the risk for excessive water temperatures in an underground storage was low and with elevated temperatures occurring only a couple of days per year. The conclusion is that Sandvik AB has good opportunities for rainwater harvesting to substitute drinking water in the cooling system but need to develop higher capabilities for storage systems to achieve higher efficiency.

The approach to water management worldwide is currently in transition, with a shift from centralised infrastructures to greater consideration of decentralised technologies, such as rainwater harvesting (R WH). Initiated by recognition of drivers, including water demand, increasing risk of ground-water pollution and flooding, the value of R WH is filtering across the academic-policy boundary. However, in Nigeria, implementation of sustainable water management (SWM), such as R WH systems, is inefficient social, environmental and technical barriers, concerns and knowledge gaps exist, which currently restrict its widespread utilisation. This inefficiency contributes to water scarcity, water-borne diseases, and loss of lives and property due to flooding. Meanwhile, several RWH technologies have been developed to improve SWM through both demand and storm-water management. Such technologies involve the use of storage tanks, surface water reservoirs and ground-water recharge pits as storage systems. A framework was developed to assess the significance and extent of water management problems, match the problems with existing RWH-based solutions and develop a robust ready-to-use multi-criteria analysis tool that can quantify the costs and benefits of implementing several RWH-based storage systems. The methodology adopted was the mixed method approach, involving a detailed literature review, followed by a questionnaire survey of 1067 household respondents, 135 Nigerian Architects and Civil Engineers and focus group discussion with Stakeholders. A total of 1042 sets of data were collected through a questionnaire survey and analysed using SPSS, Excel and selected statistical methods to derive weightings of the attributes for the tool. Following this, three case studies were selected to collect data for hydrological modelling using the RainCycle model. From the results it is found that the most important barrier constraining sustainable R WH regime in Ibadan was obsolete and insufficient operational equipment, followed by poor renumeration of water corporation staff and misuse of available funds. In addition, the measure of importance of storage capacity was established, with the highest score of 4.5 which reflects the general inadequacy of storage as a major barrier to the adoption of RWH as a sustainable water management method. Further, respondents' major health hazards associated with drinking contaminated water was established. A larger proportion (61.2%) of respondents chose prevalence of typhoid fever; some have a prevalence of diarrhea (19.4%), while few of respondents ' water sources is free from water-borne diseases (2 .3%). The tool developed is an integrated platform of related evaluation techniques, including Whole Life Cycle Cost Analysis and Multi-Attribute Utility Theory. The tool uses data including cost and quantities of materials for building a RWH storage system and quantifies the cost and benefits of alternative RWH-based systems that can improve project management. This tool is novel, given its integration of the analytical techniques mentioned above and application for selecting the most appropriate RWH-based SWM systems. The implementation of the tool is envisaged to provide an objective platform for the quantification of the costs and benefits of RWH-based systems prior to implementation.

Water resources in Scotland are under immense pressure despite the perception that it rains a lot and there are abundant water resources. High amount of energy is utilized for the transport and treatment of water for consumption which contradicts the UK government’s carbon neutral agenda. Climate change is also expected to alter precipitation patterns in the UK especially Scotland despite the perception that it rains a lot and there are abundant water resources. There is the need to adapt to water-related changes by ensuring reliable water supply to households whilst protecting the natural environment. This study explored the feasibility of rainwater harvesting (RWH) and climate change impacts on water supply in some selected peri-urban areas in Scotland. Other parameters of a water neutral development in Scotland were explored in the form of water consumption, water saving devices and water-related energy activities. Paper questionnaires were administered randomly to households using private water supply (PWS) in three local areas: Highland, Scottish Borders and Aberdeenshire and one household on the public mains water supply (MWS), Edinburgh over a period of 4 months. Overall, 378 residents’ responses and 8 stakeholders were interviewed on the feasibility of RWH in Scotland. Residents surveyed (98%) were aware of climate change in terms of the media, friends, and community. There were a lot of neutral outliers and negative responses from residents surveyed as to whether climate change was happening. When “wording” like the weather, floods, droughts, and water pollution were used, residents could relate to it happening and having a negative impact on their water resources. Just over half (53%) of residents surveyed had “no water saving device” and the most water saving device was a dual-flush toilet (32.9%). A high percentage (66.3%) believed it was important to conserve water through alternatives like RWH. For RWH to be acceptable, and implemented in Scotland, majority (66.7%) of residents felt having RWH would not be financially beneficial to them and their household but will implement it if given some form of grants. There was a distinct difference between PWS users MWS users; high proportion of PWS users perceived RWH not to be financially beneficial to them. More than half of the residents surveyed (55.6%) were willing to consider RWH if will ensure there was always constant water available and if it was easy to use (54.6%). Stakeholders felt, it will be difficult to implement RWH in Scotland, and sometimes confused RWH with greywater. Stakeholders perceived RWH as a climate change mitigation solution impossible.

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.

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.

Ce travail de recherche vise à appréhender les effets engendrés à terme sur la gestion urbaine de l'eau par le développement progressif de la pratique de récupération et d'utilisation de l'eau de pluie (RUEP), et plus particulièrement sur l'alimentation en eau potable. Il est réalisé de manière prospective à l'échelle de l'agglomération parisienne. Plus largement, cette recherche constitue une contribution au débat ouvert depuis quelques années relatif à la remise en question progressive du modèle centralisé de gestion de l'eau en milieu urbain. Après une description de la pratique urbaine de REUP, ce travail établit un état de l'art des outils et des méthodes scientifiques s'y rapportant, et suggère de se focaliser sur le développement d'une approche de changement d'échelles. L'objectif est de produire, à une échelle urbaine, une estimation significative des économies d'eau potable réalisables en substituant à celle-ci de l'eau de pluie récupérée pour des usages ne requérant pas une qualité d'eau alimentaire. Pour ce faire, nous proposons une approche basée sur l'évaluation séquentielle à l'aide d'une échelle intermédiaire (la commune), d'une logique de regroupement de bâtiments aux caractéristiques comparables au regard de la RUEP et de quatre principes (distinction, agrégation, majoration, hiérarchisation).Sur l'agglomération de Paris, la méthodologie mise en œuvre montre que l'eau de pluie récupérée est susceptible de représenter un potentiel équivalent à 65% des besoins en eau non potable et à 11% du volume d'eau potable distribué. Le travail met également en évidence que le secteur résidentiel constitue le gisement principal de ce potentiel, car il détient 2/3 du potentiel global de l'agglomération. Une première analyse du système d'acteurs impliqués dans la RUEP en milieu urbain complète ce travail. Cette analyse permet de dégager un sous ensemble particulier d'acteurs qui ont la capacité d'effectuer une action « levier » sur la diffusion de cette pratique sur une échelle urbaine, soit directement en raison de leur capacité d'action collective (un ensemble de bâtiments par exemple), soit indirectement au travers de leur capacité d'influencer sur les propriétaires des bâtiments (mécanismes d'incitation notamment).Au final, ce travail permet de situer la RUEP en milieu urbain au sein du débat général portant sur les mutations que connaît la ville d'aujourd'hui
This research aims at assessing the effects generated, on management of urban water in the long term, by progressive development of rainwater harvesting (RWH), and more particularly on the drinking water supply. It is carried out in a prospective way on the scale of Paris and its suburbs. On the whole, this research contributes to a controversy about the validity of a centralized model of management of water in an urban environment. After a description of the RWH in urban areas, this report presents state of the art tools and scientific methods, and focuses on the development of a scaling approach. The objective is to produce, a significant assessment of potential potable water savings (PPWS), on an urban scale by substituting part of it by rainwater recovered for uses which do not require such quality. With this aim, we propose an approach based on sequential evaluation using an intermediate scale (the municipality), on merging of buildings with similar characteristics related to RWH and four methodological principles (modeling, aggregation, increase, Ranking strategy)Applied to the Paris agglomeration, the implemented methodology shows that the recovered rainwater volume is likely to represent a potential equivalent of 65% of the demands for non-drinking water and of 11% of the drinking water distributed. This research also highlights that the residential sector constitutes the major contribution of this potential, because it holds 2/3 of the total potential to the Paris agglomeration. The first analysis of the system of actors implied in the RWH in urban environment has also been developed. This analysis makes it possible to identify a specific subset of actors who have the capacity to carry out an “lever” action in generalizing this practice on an urban scale, either directly because of their capacity of leading a collective action (for a set of buildings for example), or indirectly through their capacity to act on the owners of the buildings (by incentive mechanisms in particular).Finally, this work positions RWH in on urban environment within the general debate related to the evolution of present cities

Thesis (MSc)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Domestic rainwater harvesting (DRWH) refers to the collection and storage of rainwater for domestic purposes and in an effort to achieve the Millennium Development Goals (MGD), the South African government has started an initiative where DRWH tanks are financed in sustainable housing schemes in an aim to provide an additional water source directly to households. Although many provinces, including parts of the Eastern Cape and KwaZulu Natal, have been using harvested rainwater as a potable water source, there are a limited number of studies indicating the quality of harvested rainwater in South Africa. However, many studies, internationally, have indicated that while the practice of harvesting rainwater is gaining popularity, rainwater quality is not within potable standards (Chapter 1). During the first phase of the study, rainwater samples were collected from the Kleinmond Housing Scheme (Western Cape, South Africa). From a cluster of 411 houses, the DRWH tanks connected to 29 houses were selected for monitoring the microbial and physico-chemical properties of harvested rainwater. Drinking water guidelines stipulated by SANS 241 (2005), DWAF (1996), ADWG (NHMRC and NRMMC, 2011) and WHO (2011) were used throughout the study to monitor the quality of rainwater. Eight sampling sessions were then conducted from March to August 2012, during a high and low rainfall period. Overall, the physico-chemical parameters of the rainwater samples were within the respective drinking water guidelines. However, the microbiological analysis verified results obtained in international studies, and showed that the indicator bacteria numbers present in the DRWH samples exceeded the stipulated guidelines (Chapter 2 and 3). Species specific primers were also used to routinely screen for the virulent genes, aggR, stx, eae and ipaH found in Enteroaggregative E. coli (EAEC), Enterohaemorrhagic E. coli (EHEC), Enteropathogenic E. coli (EPEC) and Enteroinvasive E. coli (EIEC), respectively, in the rainwater samples. The virulent pathogenic E. coli genes were then detected in 3% (EPEC and EHEC) and 16% (EAEC) of the 80 rainwater samples collected routinely during the sampling period from ten DRWH tanks (Chapter 3). Bacterial isolates selected during the high rainfall period (June to August 2012), as well as PCR assays performed on total genomic DNA extraction from the rainwater samples, confirmed the presence of numerous pathogenic bacteria including Legionella spp. Klebsiella spp. and Shigella spp. Yersinia spp. were also isolated and detected for the first time in DRWH tanks (Chapter 4). Based on the results obtained in the first phase and as many studies have indicated the poor quality of rainwater, the second phase of the project was aimed at designing and monitoring point of use treatment systems. Three polyethylene DRWH tanks (2000 L) were installed at the Welgevallen Experimental farm, Stellenbosch University, South Africa. Various treatment systems, such as activated carbon and slow sand filtration, solar pasteurization and a combined activated carbon/PVA nanofibre filtration column, were then intermittently connected to the three DRWH tanks during the high rainfall period (June to October 2013). Results for slow sand filtration and activated carbon filters indicated that the biological layer that had developed on the filtration media had not matured and for this reason chemical and microbial parameters were not reduced to within drinking water guidelines. A polyvinyl (alcohol) (PVA) nanofibre membrane without activated carbon in a column filtration system was analysed and results indicated that this system was also not effective in reducing the microbial numbers to within drinking water guidelines. Lastly, by utilising a PVA nanofibre membrane with activated carbon in a column filtration system, one litre of potable water was produced and all heterotrophic bacteria, E. coli and total coliform counts were reduced to zero and were within drinking water guidelines (Chapter 5). For the solar pasteurization system (Chapter 6), at treatment temperatures of greater than 72°C, all heterotrophic bacteria, E. coli and total coliforms were reduced to zero and were within drinking water guidelines. However, PCR assays confirmed the presence of Yersinia spp., Legionella spp., and Pseudomonas spp., at temperatures greater than 72°C. Results for chemical analysis also indicated all cations were within the international and national drinking water guidelines, with the exception of iron, aluminium, lead and nickel, which were detected in the pasteurized rainwater samples and were above the respective guidelines. It is hypothesised that these elements could have leached from the stainless steel storage tanks of the pasteurization system and it is therefore recommended that the storage tank of the pasteurization system be manufactured from an alternative material, such as a high grade polymeric material, which is able to withstand the high temperatures yet will not negatively influence the quality of harvested rainwater.
AFRIKAANSE OPSOMMING: Reënwater versameling vir huishoudelike gebruik verwys na die versameling en berging van reënwater vir huishoudelike doeleindes. In 'n poging om die Millennium Ontwikkelingsdoelwitte (MOD) te bereik het die Suid-Afrikaanse regering ‘n inisiatief begin om finansiële bystand aan huishoudings te verleen vir die implementering van reënwater tenke, in ‘n poging om ‘n addisionele water bron direk aan huishoudings te verskaf. Hoewel baie provinsies, insluitend dele van die Oos-Kaap en KwaZulu-Natal, reënwater gebruik as ‘n drinkbare water bron, is daar 'n beperkte aantal studies beskikbaar oor die gehalte van versamelde reënwater in Suid-Afrika. Baie studies internasionaal het egter al aangedui dat, alhoewel die praktyk van die versameling van reënwater besig is om in gewildheid toe te neem, die kwaliteit van reënwater nie binne drinkbare standaarde is nie (Hoofstuk 1). Tydens die eerste fase van die studie is reënwater monsters geneem van die Kleinmond Behuisings Skema (Wes Kaap, Suid Afrika). Van ‘n kompleks van 411 huise, is reënwater tenke van 29 huise geselekteer vir die monitering van die mikrobiese en fisiese-chemiese eienskappe van versamelde reënwater. Drinkwater riglyne soos gestipuleer deur SANS 241 (2005), DWAF (1996), AWDG (NHMRC en NRMMC, 2011) en WHO (2011) was regdeur die studie gebruik om die kwaliteit van reënwater te monitor. Reënwater monsters is tydens agt geleenthede geneem vanaf Maart tot Augustus 2012, tydens die hoë en lae rëenval periode. Oor die algemeen was die fisiese-chemiese parameters van die reënwater monsters binne die onderskeie riglyne vir drinkwater. Mikrobiese analises het egter die resultate van internasionale studies bevestig en het aangedui dat die getal indikator bakterieë teenwoordig in the reënwater die gestipuleerde riglyne oorskry (Hoofstuk 2 en 3). Spesies spesifieke inleiers was gebruik om die virulensie gene aggR, stx, eae en ipaH, teenwoordig in onderskeidelik Entero-aggregatiewe E. coli (EAEC), Entero- hemorragiese E. coli (EHEC), Entero-patogeniese E. coli (EPEC) and Entero-indringende E. coli (EIEC), in die reënwater monsters op te spoor. Die virulente pathogeniese E. coli gene was in 3% (EPEC en EHEC) en 16% (EAEC) van die 80 reënwater monsters, geneem van 10 reënwater tenke tydens die studie, waargeneem (Hoofstuk 3). Bakteriese isolate geselekteer tydens die hoë reenval periode (Junie tot Augustus 2012), so wel as PKR (polymerase ketting reaksie) ontledings uitgevoer op genomiese DNS wat van die reënwater monsters ge-ekstraheer was, het die teenwoordingheid van verskeie patogeniese bakterieë, insluitend Legionella spp., Klebsiella spp. en Shigella spp., bevestig. Dit is ook die eerste keer wat Yersinia spp. in versamelde reënwater waargeneem is (Hoofstuk 4). Die doel van die tweede fase van die projek was om water behandeling sisteme by die punt van gebuik te ontwerp en te monitor aangesien die resultate wat gedurende die eerste fase verkry is, sowel as vele ander studies, aangedui het dat die kwaliteit van versamelde reënwater swak is. Drie poli-etileen reënwater tenke (2000 L) was geïnstalleer op die Welgevallen Eksperimentele plaas van die Universiteit van Stellenbosch, Suid Afrika. Verskeie water behandeling sisteme, soos geaktiveerde koolstof en stadige sand filters, sonkrag pasteurisasie en ‘n gekombineerde geaktiveerde koolstof/PVA nanovesel filtrasie kolom, was met tye gekonnekteer aan verskeie reënwater tenke gedurende die hoë reënval periode (Junie to Oktober 2013). Resultate van die stadige sand en geaktiveerde koolstof filters het aangedui die biologiese laag nog nie ver genoeg ontwikkeld het nie en daarom was die chemiese en mikrobiese parameters nie verminder to binne die riglyne vir drinkwater nie. ‘n Polyviniel (alkohol) nanovesel membraan sonder geaktiveerde koolstof binne ‘n kolom filtrasie sisteem, was geanaliseer en resultate het aangedui dat hierdie sisteem ook nie die mikrobiese getalle verminder het tot drinkwater standaarde nie. Laastens, deur gebruik te maak van ‘n PVA nanovesel membraan met geaktiveerde koolstof in ‘n kolom filtrasie sisteem, was een liter drinkbare water geproduseer met alle heterotrofiese bakterieë, E. coli en totale koliform getalle verminder tot nul en was binne die riglyne vir drinkwater (Hoofstuk 5). Vir die sonkrag pasteurisasie sisteem (Hoofstuk 6), by behandelings temperature van groter as 72°C, was alle heterotrofiese bakterieë, E. coli en totale koliform getalle verminder tot nul en was binne die riglyne vir drinkwater. Maar PKR ontledings het die teenwoordigheid van Yersinia spp., Legionella spp., en Pseudomonas spp. by temperature groter as 72°C bevestig. Resultate van die chemiese analises het ook aangedui dat alle katione binne die drinkwater riglyne was, met die uitsondering van yster, aluminium, lood en nikkel. Hierdie elemente was in die gepasteuriseerde reënwater monsters waargeneem met konsentrasies wat die onderskeie riglyne oorskry het. Dit word gehipoteseer dat hierdie elemente uit die vlekvrye staal van die bergings tenk van die pasteurisasie sisteem kon uitgeloog het. Daarom word dit aanbeveel dat die bergings tenk van die pasteurisasie sisteem geproduseer moet word van ‘n alternatiewe materiaal, soos ‘n hoë graad polimeriese material, wat hoë temperature kan weerstaan maar nie ‘n negatiewe invloed sal hê op die kwaliteit van versamelde reënwater nie.

The United Nations Millennium Development goals aim to make improvements in access to potable water. In the Bocas del Toro region of Panama, rainwater harvesting systems are making that goal more attainable. Rainwater harvesting, especially in rural, difficult access areas, may be a viable water source improvement that will allow a greater population to access improved water. This study uses the Carnegie Mellon University Economic Input-output Life Cycle Assessment tool to assess the embodied energy of plastic and ferrocement rainwater harvesting systems in rural Panama. Rainwater harvesting systems are assessed as source improvement technologies that increase access to potable water. This study adds to and compares its results to other source improvement LCAs that would potentially benefit developing communities in lesser developed countries.

Climate change (CC) science has made significant progress in development of predictive models. Despite these recent advances, the assessment of CC impacts in urban watersheds remains an area of active research, in part due to the small temporal and spatial scales needed to adequately characterize urban systems. Urban watersheds have been the focus of considerable efforts to restore hydrology and water quality, and the aquatic habitat of receiving waters, yet CC impacts threaten to reduce the effectiveness of these efforts. Thus, assessing the impacts of CC in urban watershed assessment are essential for assuring the success of water quality improvement programs and is an important research need. Simulations of CC for the 2041-2068 period were developed using downscaled Global Climate Models (GCMs) from the North American Regional CC Assessment Program (NARCCAP) and Coupled Model Intercomparison Project Phase 5 (CMIP5) to forecast precipitation and temperature time series. This data were then used to force a Storm Water Management Model (SWMM) of the Difficult Run watershed of Fairfax County, Virginia, a tributary of Potomac River, which flows into Chesapeake Bay. NARCCAP uses a scenario represents a medium-high greenhouse gas emissions assumption, A2; the latter, uses five GCMs, and two Representative Concentration Pathways (RCP 4.5 and 8.5) scenarios in an ensemble approach to better assess variability of model predictions in presenting precipitation, temperature, runoff quantity and quality. Then, the effects of CC on runoff peak, volume, and nutrient and sediment loads delivered to the Chesapeake Bay and on the treatment performance of a very common stormwater control measure (SCM), retention ponds, was assessed. Rainwater Harvesting (RWH) systems are an unusual SCM in that they recycle and reuse stormwater, normally from rooftops, and increase water supply and reduce runoff. The efficiency of RWH systems for projected CC for these dual purposes was assessed. NARCAAP data for selected locations across the U.S. were statistically downscaled using a modified version of the equiratio cumulative distribution function matching method to create a time series of projected precipitation and temperature. These data were used to force a simulation model, the Rainwater Analysis and Simulation Program (RASP) to assess the impacts of CC on RWH with respect to the reliability of water supply and runoff capture. To support CC modeling, an easy-to-use software tool, RSWMM-Cost, was developed. RSWMM-Cost automates the execution of SWMM, which is commonly used for simulating urban watersheds. Several features were incorporated into the RSWMM-Cost tool, including automated calibration, sensitivity analysis, and cost optimization modules; the latter can assist in identifying the most cost-effective combination of SCMs in an urban watershed. As an example, RSWMM-Cost was applied to a headwater subcatchment the Difficult Run watershed.
Ph. D.

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The current projects of rainwater plumbing systems are extremely simple and present only one exclusive concern: to divert the rainfall from the place where it occurs to the drainage public system. In general, it s possible to verify that they do not attend even the word semantic meaning. The no existence of a coordinated set of action aiming at ampler results makes rainwater plumbing system unconcerned with the surrounding area, not composing harmonically with the urban site in particular, and the environment as a general form. Generally, designers expect only rainwater goes toward out of the site, and that is a good result of a good system. Due the lack of attention to the impact that generates and does harm to society, they ignore its potential as instrument of water building conservation. They do not assess correctly its capacity as a source of supply of so expensive and scarce water, according with its necessities, conveniences or limitations that can exist. Therefore, the goal of this study is to propose a new function for the rainwater plumbing system, in special for Ribeirão Preto municipal school buildings, becoming it from a passive to an active system of environment protection. With a proper and molded conception for this new proposal, the system must contemplate the aspects related to the reduction of the impacts caused by the civil construction activities on urban sites, its preservation and providing environment education for people and also, as an worthy water building management tool.
Os atuais projetos dos sistemas prediais de água pluvial são em sua grande maioria, extremamente simples, apresentando uma única e exclusiva preocupação: a transferência da precipitação do local onde ocorre para o sistema público de drenagem, constituído por sarjetas, galerias e por fim, os córregos e rios. Verifica-se que, em geral, não atendem nem ao sentido semântico da palavra sistema. A inexistência de um conjunto coordenado de ações visando um resultado mais amplo faz com que o sistema predial de água pluvial se dissocie de seu entorno, sem se compor harmônicamente com o meio urbano em particular, e o meio natural de uma forma geral. Na concepção atual de seus projetistas, o simples encaminhamento destas águas para fora da edificação é o resultado esperado de um bom sistema. Alheios ao impacto que gera e que penaliza a socidade, passam ao largo de seu potencial como instrumento de conservação de água nas edificações. Ignoram sua capacidade de suprir as mesmas com tão caro e cada vez mais escasso recurso, de acordo com as necessidades, conveniências ou limitações que possam existir. Portanto, o objetivo deste trabalho consiste na proposição de uma nova função para o sistema predial de água pluvial, em especial nas escolas muncipais de Ribeirão Preto, transformando-o de um sistema passivo de captação e drenagem em um sistema ativo de conservação ambiental. Com uma concepção própria e moldada para esta nova proposta, o sistema deve contemplar os aspectos relacionados à redução dos impactos causados pela ocupação do solo no meio urbano, à preservação e educação ambiental e também, à gestão da oferta de água nas edificações.

A escassez de água no planeta já é uma realidade pontual, inclusive já despontando no horizonte, em nosso país, fora do polígono da seca: na região metropolitana de São Paulo, o modelo de adução, a partir de bacias circunvizinhas, está perto de exaurir, pelos custos que esse tipo de solução adotada desde a época do império romano acarreta nas tarifas para o consumidor final. Assim, a busca pelas chamadas soluções racionais têm, cada vez mais, ganhado adeptos e, dentre estas, a que se tem mostrado mais eficiente e mais eficaz é a tecnologia do esgotamento sanitário a vácuo, visto ser a bacia sanitária a responsável por aproximadamente 40% do consumo residencial de água, e por um percentual semelhante também em edifícios comerciais. A partir do estudo de caso no edifício-sede da Secretaria de Orçamento Federal SOF, em Brasília, foi constatada economia de 30% no consumo médio de água, medido em metros cúbicos, depois da implantação do sistema a vácuo - em substituição ao sistema gravitacional, ocorrida em janeiro de 2008 a par de um aumento de apenas 2% no consumo de energia elétrica, medido em kWh, não produzindo ônus, por força do contrato com a concessionária local de eletricidade, do tipo azul. Foram feitas, ainda, comparações com alternativas de abastecimento, quais sejam água de reuso e o aproveitamento de águas pluviais, este mais comum no Brasil embora nitidamente mais recomendável para construções com até dois pavimentos, enquanto aquele, por enquanto, pode ser considerado uma prospecção teórica para as condições de nosso país
The water shortage in the planet is already a punctual reality that is already rising in our country outside the drought polygon (in northeastern part of Brazil). In the metropolitan area of São Paulo the adduction model coming from the neighboring basins is on the brinks of exhaustion, because this kind of solution costs, adopted since the Roman Empire times, brings up to tariffs to the final customer. In this manner, the search for the so called rational solutions has gained more and more followers and among these the one that has shown more efficiency and accuracy is the vacuum sewerage technology, considering that sanitary basin is responsible for almost 40% of the residential water consumption and a similar percentage occurs also in trade buildings. Taking the case study in the headquarter building of Secretaria de Orçamento Federal (SOF), in Brasília, it was verified a 30% economy in the average water consumption, measured in cubic meters, since the vacuum system was established (replacing the gravitational system), on January 2008, informed about only 2% increase in the electricity consumption, measured in kWh, it means that there was no effective increase in the electricity bill, once the local provide company contract, of the blue type, has foretold small oscillations in the supply without deduction on the bill. It was still done some comparative descriptions with others alternatives water supplies, whichever be grey water and rainwater harvesting, this one widely used in Brazil although it is more suggested to up to two floor buildings while the other, for the time being, can be considered as a theoretical prospection in our country

碩士
國立臺灣海洋大學
河海工程學系
101
Water resources become the major issue in recent years. Non-uniformly distribu-tion of rainfall both in space and time is the major reason. In the early time, rainwater collected from buildings is mainly provided as an alternative water resource for resi-dential, educational and commercial water uses. This will alleviate the pressure of water shortage. In recent years, other benefits of rainwater harvesting have been noti-fied. Among these benefits, urban storm water mitigation that reduces the peak and volume of storm water is the major benefit which will reduce the problem of urban flood. But there is little research focusing on the dual purposes design of rainwater harvesting system. This research will try to use the existing examples to investigate the operation strategies to meet the dual purposes of rainwater harvesting system. Currently, three methods for estimating the storage volume of rainwater harvest-ing system have been used. They are National Taiwan Ocean University, National Lan-Yang University of Technology and method from green building evaluation manual. In the research, calculation procedures for these three methods were devel-oped and written by the language of Microsoft Office Excel. Three existing cases, Keelung Harbor Bureau (1), Nan-tou Human Administration Local Administration Center (2), and Chi-I University of Technology (3), are chosen. The designed data of these three cases and daily rainfall data for three rainfall stations during years between 2000 and 2009 and rainwater use data for these three examples in year of 2010 are used to evaluate and select the reasonable design method for storage volume design and this method will be used in the following analysis. For existing three examples, 0%, 25%, 50%, 75% and 100% of storage volume are used for detention space during wet season. The detention volume will be dis-charged in six hours. Therefore, existing systems have both functions of water supply and flood mitigation during wet season. The reasonable space for detention is decided by optimal benefits of water supply and flood peak reduction. In the analysis, hourly rainfall data in wet season in year 2010 from three rainfall stations near these examples are used. The results show that larger detention space results in less water supply and higher flood peak reduction. For example 1, detention space 50% will achieve the optimal benefits for dual purposes; 75% for example 2; between 50% and 75 % for example 3. For flood peak reduction compared with no rainwater harvesting installation, the average flood peak reduction for these three examples are 80%, 70% and 50%, respectively. In high rainfall area for example in Keelung, percentage of flood peak reduction is high. Contrarily, percentage of flood peak reduction is low for low rainfall area such as in Taichung.

碩士
國立聯合大學
建築學系碩士班
99
As long as EEWH has been executed, most of the cases choose the Roof Rainwater Harvesting Systems as the Garden Irrigation to retrieve the huge water consumption item. In order to understanding the operating effectiveness of the rainwater harvesting system of these cases, this research chooses 155 case which had passed the green building marker, water resource guideline between 2007 and 2010 to process the computer simulation. In addition, it discusses the rationality and water saving benefit of the case planning and design. Moreover, it also focuses on 40 cases on the midland of Taiwan to do the questionnaire survey and locality interview and pick up three places to do the long term monitor experiment. The result of the questionnaire survey, in forty cases, there are only four cases do not feel the benefit of water saving, major cases has regular preserve the rainwater harvesting systems and do not have any confusion of exercise. There are five cases did not know the rainwater harvesting systems, and four cases use the equipment less than three years after setting. After the long term monitor, the great rainwater harvesting systems effect is came from the well uphold and organization system. Moreover, the setting of the monitor system is important for the rainwater harvesting systems to operate well. Unfortunately, the results of the questionnaire survey shows that there are only six cases have the monitor system and of the computer simulation presents that there are only fifty-two cases attain to more than 20% water displace rate and only sixty-four cases, the setting of the monitor system is on the reasonable range. In addition, most of the system do not consider about the support relationship between the rainwater collection area and the volume of the store tank. Finally, this research provides an easily evaluation model and takes the water saving rate as the scoring reference. Furthermore, it looks forward to advance the roof rainwater harvesting systems to a reasonable planning and design and raise the water saving benefit of the roof rainwater harvesting systems through the evaluation model.

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.

Tese de Doutoramento em Ciências Agronómicas e Florestais
Pressure on water resources have been increasing over time, due to external forces such as population growth, irregular distribution, water waste, aquifer contamination and also climate change. Global climate change is expected to intensify current and future tensions over water resources and will increase the frequency and intensity of droughts and floods. Thus, in addition to extreme events such as floods and droughts, water quality and forest fire problems are also a concern. Therefore, some methodologies have been tested to improve, mitigate or help better management and planning of water and thus combat these water-related problems. In Chapter 1, a brief introduction is made about pressures on the water resources and their consequences for the environment and society, while some solutions are suggested. An improved framework model to allocate optimal rainwater harvesting sites in small watersheds for agro-forestry uses is presented in Chapter 2. The developed model aims to select optimal RWH sites based on a multi-criteria analysis involving physical, socioeconomic and ecologic parameters. The choice of specific socio-economic parameters allowed the selection of optimal places away from urban centres or large farming areas, which prevent the use of stream water with excessive anthropogenic nutrients in irrigation that may cause accumulation of nitrosamines in the food chain with severe consequences to human health. Chapter 3 discusses rainwater harvesting in catchments for agro-forestry uses: A study focused on the balance between sustainability values and storage capacity. This model follows the line of the previous chapter, but was significantly improved. In this case, attention was paid to the balance between sustainability values and storage capacity of RWH systems. The study aimed at ranking 384 rainfall collection sub-catchments as regards installation of RWH sites for crop irrigation and forest fire combat. The practice of RWH at the catchment scale is frequently concerned with ecological sustainability values, namely through the aesthetic landscape enhancement. To naturally cope with these values, RWH infrastructure (dam wall) heights must not exceed ≈3 m. The results showed that more engineered dams may not always ensure all sustainability values but warrant much better storage. The limiting parameter was the dam wall height, because 217 sub-catchments were found to drain enough water for irrigation and capable to store it if proper dam wall heights were used. Chapter 4 argue about flood risk attenuation in critical zones of continental Portugal using sustainable detention basins. Within the framework of Directive 60/2007/EC (Floods Directive), Flood Risk Management Plans were developed for 23 critical flood risk zones identified in Portugal, capable to eliminate the high and very high flood risk areas instead of attempting to ensure full control of the flood in all potentially threatened areas. The results showed that the number of sustainable detention basins is reduced by about 30% when the full flood control model is used. Although the results indicate the possibility of installing more unsustainable than sustainable detention basins, in all critical areas, only three do not provide sustainable solutions. Therefore, in these critical areasthe construction of highly designed structures would be mandatory. “Can Land Cover Changes Mitigate Large Floods? A Reflection Based on Partial Least Squares-Path Modeling” was a question we tried to answer in Chapter 5. The aim was to verify, using a Partial least Squares-Path Model (PLS-PM), if changes in specific catchment variables, such as forest occupation or imperviousness of urban areas, would result in lower dam heights. In some realistic scenarios, the forecasted changes comprised 30% increase in forest areas or 30% decrease in impervious urban areas. Other purely academic scenarios were also tested, comprehending, for example, the duplication of forest areas or the reduction of catchment slope. In all cases, however, the dam wall heights did not fall significantly and remained very high. Therefore, the answer to the initial question is that non-structural measures may not always be an efficient way to reduce stream flows in a manner that flood detention can be achieved through construction of sustainable dam structures. Finally, in Chapter 6, the general conclusions and future perspectives were presented.
As pressões sobre os recursos hídricos têm aumentado ao longo do tempo, devido a forças externas como crescimento populacional, distribuição irregular, desperdício de água, contaminação de aquíferos e também devido às alterações climáticas. Estas alterações, a nível mundial tendem a intensificar as tensões atuais e futuras sobre os recursos hídricos e aumentar a frequência e a intensidade de secas e inundações. Assim, além destes eventos extremos, a qualidade da água e os problemas com incêndios florestais também são uma preocupação. Portanto, algumas metodologias foram testadas para mitigar ou melhorar a gestão e planeamento hídrico e, assim, combater esses problemas relacionados à água. No capítulo 1, é feita uma breve introdução relacionada com as pressões exercidas sobre os recursos hídricos e suas consequências para o meio ambiente e a sociedade, enquanto algumas soluções são sugeridas. Um modelo que permite encontrar locais ótimos para aproveitamento de água da chuva em pequenas bacias hidrográficas para usos agroflorestais é apresentado no Capítulo 2. O modelo desenvolvido visa selecionar locais ótimos de Aproveitamento de Águas Pluviais (AAP) com base numa análise multicritério através de parâmetros físicos, socioeconómicos e ecológicos. A escolha de parâmetros socioeconómicos específicos permitiu a seleção de locais ótimos fora dos centros urbanos ou grandes áreas agrícolas, que impedem o uso de água com excesso de nutrientes de origem antropogénica na irrigação, que podem causar acumulação de nitrosaminas na cadeia alimentar, com graves consequências para a saúde humana. O capítulo 3 discute a captação de água da chuva em bacias hidrográficas para uso agroflorestal: um estudo focado no equilíbrio entre valores de sustentabilidade e capacidade de armazenamento. Este modelo segue a linha do capítulo anterior, mas foi significativamente aprimorado. Nesse caso, foi dada atenção ao equilíbrio entre os valores de sustentabilidade e a capacidade de armazenamento dos sistemas de AAP. O estudo teve como objetivo classificar 384 sub-bacias de captação de precipitação no que diz respeito à instalação de locais de AAP para irrigação de culturas e combate a incêndios florestais. A prática de AAP à escala da bacia hidrográfica preocupa-se frequentemente com os valores da sustentabilidade ecológica, nomeadamente através da melhoria da paisagem envolvente. Para lidar naturalmente com esses valores, as alturas das infraestruturas de AAP (altura do paramento da represa) não devem exceder ≈3 m. Os resultados mostraram que barragens maiores nem sempre garantem todos os valores de sustentabilidade, mas garantem um armazenamento muito melhor. O parâmetro limitante foi a altura da represa, porque 217 sub-bacias captavam água suficiente para irrigação e eram capazes de armazená-la desde que fossem selecionadas as alturas adequadas da infraestrutura. O capítulo 4 discute a atenuação do risco de inundação em zonas críticas de Portugal continental, usando bacias de retenção sustentáveis. No âmbito da Diretiva 60/2007 / CE (Diretiva de Inundações), foram desenvolvidos Planos de Gestão de Risco de Inundação para 23 zonas críticas de risco de inundação identificadas em Portugal, capazes de eliminar as áreas de alto e muito alto risco de inundação, em vez de tentar garantir o controle total de inundação em todas as áreas potencialmente ameaçadas. Os resultados mostraram que o número de bacias de retenção sustentável é reduzido em cerca de 30% quando o modelo completo de controle de inundação é usado. Embora os resultados indiquem a possibilidade de instalar mais bacias de retenção não-sustentáveis do que sustentáveis, em todas as zonas críticas, apenas três não fornecem soluções sustentáveis. Portanto, nessas zonas críticas, a construção de infraestrutura altamente projetadas seria a única solução. “As alterações do uso do solo podem atenuar grandes inundações? Uma reflexão baseada na modelação de PLS-PM” foi uma pergunta que tentamos responder no capítulo 5. O objetivo era verificar, se alterações em variáveis específicas da bacia hidrográfica, como ocupação florestal ou impermeabilização de áreas urbanas, resultaria em menores alturas de barragens, utilizando um modelo de PLS-PM (Partial Least Square - Path Modeling). Em alguns cenários realistas, as alterações previstas incluíram aumento de 30% nas áreas florestais ou redução de 30% nas áreas urbanas impermeáveis. Também foram testados outros cenários puramente académicos, compreendendo, por exemplo, a duplicação de áreas florestais ou a redução do declive da bacia hidrográfica. Em todos os casos, no entanto, a altura da represa não desceu significativamente, permanecendo muito alta. Portanto, a resposta para a pergunta inicial é que as medidas não estruturais nem sempre podem ser uma resposta eficiente na redução dos escoamentos, assim sendo, a retenção da água que provoca inundações pode ser feita através da construção de barragens sustentáveis. Finalmente, no capítulo 6, foram apresentadas as conclusões gerais e as perspetivas futuras.

博士
國立成功大學
水利及海洋工程學系碩博士班
98
The water shortage of today’s world is one of the most challenging problems which is caused by human or natural calamities. In Taiwan, especially during typhoon, the turbidity of raw water increases beyond the treatment level and the plant cannot supply required amount of water for a couple of days. The purpose of this study is to introduce rainwater as an alternative and reliable water source during short term emergency period, and assess the efficacy and mains water saving of the dual-mode Rainwater Harvesting System (RWHS) for supplying emergency and ordinary water demands in case of primary school and household having different numbers of family members for both northern and southern Taiwan as case study. A dual-mode RWHS was designed for this study as supplement of the existing supply system to support the selected non-potable toilet and urinal flushing (WC) component. An optimal design algorithm was developed using a newly developed modified YAS (yield after spillage) model for this study which originated from YAS release rule. Two new important parameters were also introduced for the system which would help to use the dual-mode system without any shortage. One of the two is minimum safe storage volume (mssv), which is equivalent to three days demand. Another parameter is adapted storage volume (asv). This asv volume level will be guided according to the users requirements. If there is no rainfall and the water level reaches mssv level, the system will collect and store mains supply up to asv level. Another model was developed to simulate the water release system and to find the minimum number of days the system can support using rainwater with different tank volumes when the rainfall is more than 250 mm/day. The case study results of primary school for Taipei revealed that the mains supply savings and benefit would be significant to reduce the water shortage. The case study results for Tainan explored that the mains supply savings and benefit would be less significant than that of Taipei to reduce emergency water shortage. The case study of the families having two, four and six members’ for both Taipei and Tainan was performed. The study results found that for all kinds of family members’, the system would satisfy the emergency water shortage effectively for both places. The study result proved that an optimum volume of tank can solve the emergency water shortage properly. The system was found to be more reliable in Taipei area than that of Tainan area. The study also discovered that government may provide subsidy to promote the RWHS in Taiwan.

碩士
國立臺灣海洋大學
河海工程學系
98
97% of energy in Taiwan are imported. Water shortage becomes serious because of economic development. Therefore, developing renewable energy sources and alternative water sources become important issue in the future. Renewable energy includes solar, wind, hydro, biomass energy, etc. Rainwater harvesting can replace parts of domestic water supply such as toilet flushing, irrigation, car washing, etc. Research is combing renewable energy and rainwater harvesting is rare. This study tried to combine solar power system and rooftop rainwater harvesting system. According to practical conditions, four different types of combination can be found. They are categorized: independent system (TypeⅠ); connect with public electric system (Type Ⅱ); connect water public water supply system (Type Ⅲ); standard system (Type Ⅳ). The simulation process of each type of the system has been written by Microsoft Visual Basic 6.0 selected for sample study Keelung and Penghu are with data for 1999 to 2009. Results obtained from the simulation will provide on reference for people who are interested to installing the system required. Results show that total average annual rainwater used for toilet flushing occupies 40% of water supply in Penghu area, and 30% of power generation in used. On the contrary, in Keelung area, total average annual rainwater used reaches 40% and 58% of power generation is used. For the assumed care study, the suitable storage tank volume on the ground and temporary storage volume on the roof are 5 tons and 1 ton respectively in Penghu area. For Keelung area, they are 1.5 tons and 1 ton, respectively. Both of there deployments, rainwater used for toilet flushing can reach 50% of water supply. Results obtained from this research will provide a reference for system selection but other factor may influence the system deployment.

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.
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碩士
國立臺灣科技大學
建築系
105
The research of evaluation indicator and zoning potential of rainwater harvesting system in Java, Indonesia Thesis adviser: Cheng-Li Cheng Graduate student: Diana Wijaya Abstract Rainwater harvesting system has been widely used as an alternative solution to solve the insufficient access of clean water. The optimized utilization of this system creates maximum effectiveness. However, this system is still minimally practiced in Indonesia. In this research, the rainfall data are evaluated to create a rainwater harvesting system guideline for architectural planning in Java Island, Indonesia. This proposed system is a practical sytem to identify the decision-making process and assess the solution. Rainfall data are arranged and analyzed using statistical programs. The procedure of this methodology is based on the practical application of rainwater harvesting system in Taiwan. The evaluation indicator can be used to review the proposed design and achieve optimization of rainwater harvesting system utilization in Java. These results carry implication for the use of evaluation indicator to evaluate the system design based on each district's rainfall characteristic. Keywords: rainwater harvesting system; evaluation indicator

碩士
國立臺灣海洋大學
河海工程學系
96
ABSTRACT Because of climate change, both floods and droughts hit Taiwan occasionally. Unfortunately, 97% of energy must be imported in Taiwan. Therefore, we need to explode any renewable energy and any water resource. Renewable energy includes: solar energy, wind energy, small hydraulic power etc. Among them, wind energy generation is the most feasible alternative in seashore area. And rainwater harvesting from rooftop is one of the most economic selection in Taiwan. Research for combining renewable energy and rainwater harvesting is rare till now. The purpose of this research is to assess the feasibility of combining the wind energy and rainwater harvesting system. Firstly, the 3000 W and vertical axis wind energy generation machine is installed at front yard of the 2th building of Department of Harbor and River Engineering in February 2007. In the following, efficiency coefficient of wind energy generation was examined by measured hourly wind speed and electric generated during the period of February and May 2007. From the measured data, the average efficiency coefficient of wind energy generation was found at about 0.3 which is in the range of world values. In the following, the assumed case study is studied. The assumed case with 100 m2 of roof area and two floors having 4 persons and rainwater harvesting system with 1 ton of storage tank on the floor. And rainwater is solely for toilet flush. Based on these conditions, the simulation model is constructed using Visual Basic 6.0. The hourly wind speed at wind energy generator for 2007 is correlated from Keelung meteorological station. From the simulation results, 50% of wind energy generation will be used in pumping water and 50% of rainwater is used for toilet flush.

Cape Town, South Africa, falls within a winter rainfall region, making it difficult to assess the feasibility of rain- and stormwater harvesting. The reason for this is because the region’s high water demand period coincides with the low rainfall summer season, thereby limiting the availability of this alternative water resource when most needed. During this study, rainwater harvesting for toilet flushing purposes, collected from roof surfaces, was practically assessed by means of inserted flow meters at a pilot study site in Kommetjie, Cape Town. The combined and single system roof- and land surface runoff yields and savings of commercial buildings within the Kommetjie business area, were also theoretically assessed by making use of a mathematical roof- and land surface runoff model specifically developed during this study. The statistical testing of the hypotheses statements relating to the pre- and post-harvesting savings at the pilot study building, compared against the average actual municipal water usage, were performed. Hypotheses testing were also performed in order to compare the theoretical rain- and stormwater runoff yields for the commercial business area against the average actual municipal water consumption. The conclusions drawn from this study indicated that valuable potable water, as well as related financial savings, can be achieved within a winter rainfall region, thereby making rain- and stormwater harvesting a feasible option for commercial businesses in Cape Town.
Environmental Sciences
M.Sc. (Environmental Management)

Dissertação de mestrado integrado em Engenharia Civil
Face à crise ambiental, social e económica sentida globalmente, provocada pelo aumento populacional das últimas décadas, é necessário contrariar esta crise mudando alguns aspectos no dia-a-dia do Homem. Nesta dissertação abordar-se um aspecto muito importante no combate a essa crise sentida globalmente que é a utilização e aproveitamento da água pluvial. O aumento da população mundial tem como consequência uma maior necessidade de água, tanto para consumo doméstico, agrícola ou industrial. Por isso, é necessário tomar medidas para o uso eficiente deste bem essencial, que é esgotável. Esta dissertação aborda um tema que foca na poupança de água nos usos domésticos, sendo a água potável substituída por água pluvial em fins menos nobres, tais como as descargas sanitárias, rega, lavagem de veículos e de roupa. Esta poupança é conseguida através de um Sistema de Aproveitamento de Águas Pluviais. A viabilidade do uso da água da chuva é demonstrada pela significativa redução do volume da água fornecida pelo sistema de abastecimento, tendo como consequência a diminuição dos custos em relação à água potável bem como a redução do risco de cheias em casos de episódios de pluviosidade intensos. A metodologia de ensaio adoptada nesta dissertação consiste na recolha de amostras de água armazenada nos depósitos do dispositivo de first flush com filtro incorporado desenvolvido para se proceder a análise da sua turvação através do turbidímetro Hach 2100 Q is. É também analisada a turvação da água de entrada, que é uma mistura de resíduos, folhas e água. Nesta dissertação realizam-se experiências com diferentes volumes de água, de resíduos e número de folhas. Foram utilizadas diferentes combinações destes três factores para estudar a variação da turvação da água nas diferentes etapas do dispositivo de first flush com filtro incorporado desenvolvido. Com a realização deste trabalho conclui-se que utilizando o dispositivo de first flush com filtro incorporado desenvolvido os valores de turvação de água nos diferentes depósitos do dispositivo desenvolvido vão diminuindo ao longo do seu percurso, que todas as folhas e resíduos de maiores dimensões introduzidos nos ensaios ficam retidos no Primeiro Depósito de Águas de Lavagem e que a turvação da água armazenada no Segundo Depósito de Águas de Lavagem não sofre alterações significativas consoante do volume de água introduzido.
With this environmental, social and economic crisis felt globally, caused by the increase of the population in recent decades, it is necessary to counter this crisis by changing some aspects in the human being daily activities. In this dissertation it is discussed a very important aspect for the combat of this crisis felt worldwide which is the use of rainwater. The increase of the world population results in a bigger need for water, for domestic, agricultural and industrial consumption. Therefore, it is necessary to take measures to use the water more efficiently because it is an exhaustible natural resource. This dissertation addresses a theme that focuses on saving water in domestic use, replacing the drinking water by rainwater in less noble purposes such as toilet flushing, irrigation, washing vehicles and clothing. This savings are achieved through a Rainwater Harvesting System. The feasibility of using rainwater its demonstrated by the significant reduction of the volume of water supplied by the purveyance system, resulting in the reduction of costs in relation to drinking water as well as reducing the risk of flooding in the event of intense rainfall. The test methodology adopted in this thesis is to collect samples of water stored in the deposits of the first flush device with a filter incorporated developed to analyze the water turbidity with the turbidimeter Hach 2100 Q is. It is also analyzed the turbidity of the entry water, which is a mixture of waste, leaves and water. In this thesis, experiments are carried out with different volumes of water, waste and number of leaves. Different combinations of these three factors were used to study the variation of the turbidity of the water in various stages of the first flush device with incorporated filter developed. With this work it is possible to conclude that using the first flush device with incorporated filter developed the values of turbidity of the water stored in the different deposits suffer a decrease along the course, that all the leaves and bigger size residues introduced into the rehearsals are held on the first deposit of washing waters and the turbidity of the water stored in the second deposit of washing waters does not change with the volume of water introduced.

Dissertação de mestrado integrado em Engenharia Civil
A procura de estratégias de racionalização no consumo de água ou de fontes alternativas de água têm levado ao surgimento de várias soluções, sendo algumas já utilizadas no passado mas caídas em desuso com o desenvolvimento das sociedades. Uma das soluções já adotada de forma significativa em vários países é o aproveitamento da chuva em todo o tipo de utilizações. Neste trabalho explora-se a viabilidade da implantação de um sistema de aproveitamento de água pluvial (SAAP) para fins domésticos em Portugal continental. Esta dissertação pretende ajudar a resolver a problemática do aproveitamento de água pluvial em contexto doméstico, determinando onde um SAAP pode constituir um sistema economicamente atraente e uma fonte alternativa credível de água não potável. O investimento inicial na implantação de um SAAP constitui o maior entrave na expansão deste tipo de sistema, sendo o reservatório de armazenamento de água pluvial o elemento mais dispendioso. Desenvolveu-se um programa denominado PSAAP, para fazer a simulação do aproveitamento de água pluvial. O PSAAP foi desenvolvido com o objetivo de dimensionar a capacidade ideal do reservatório e estudar a viabilidade económica do SAAP. Para um determinado SAAP, este simulador calcula iterativamente até encontrar a capacidade ideal. A capacidade ideal do reservatório de um SAAP será a capacidade que levar a que o SAAP tenha o menor período de recuperação do investimento (PRI) possível. Através do PSAAP, o utilizador pode obter a capacidade do reservatório recomendável para a sua localização, consumo e capacidade de captação da chuva, conseguindo também perceber qual o investimento inicial e o PRI associados ao respetivo SAAP. Na aplicação da ferramenta, estuda-se a implantação de um SAAP em cidades de diferentes regiões de Portugal continental, de forma a perceber a sua viabilidade em condições distintas. Estudou-se numa primeira análise a utilização de um SAAP que abastece-se apenas uma moradia unifamiliar e numa segunda análise estudou-se a utilização de um SAAP que abastece-se um conjunto de quatro moradias unifamiliares, de forma a verificar se o projeto beneficia economicamente por ser um sistema de maior dimensão. Através das simulações efetuadas no PSAAP, conclui-se que quanto mais elevado for o nível de consumo, o custo da água consumida, área de captação e a precipitação disponível, menor é o PRI do SAAP.
The demand for rationalizing strategies or alternative sources of water have led to the appearance of several solutions, some already used in the past, but have fell into disuse with the development of societies. One of the significantly solutions, already adopted in several countries, is the use of rainwater. This work explores the economic viability of implementing a rainwater harvesting system (RWHS) for domestic purposes in Portugal mainland. This dissertation aims to help solve the problem of use rainwater in the domestic context, determining where a RWHS can be an economically attractive system and a credible alternative source of non-potable water. The initial investment in the implementation of a RWHS is the major obstacle in the expansion of this type of system where the rainwater storage tank is the most expensive element. In order to study the economic viability of a RWHS and calculate the ideal capacity to the storage tank under different conditions, was developed a program for simulation of rainwater harvesting called PSAAP. For a RWHS with different storage capacities, this simulator calculates iteratively to find the ideal capacity. The ideal capacity of a RWHS’s storage tank is the capacity that leads to the RWHS has the lowest possible payback period. Through PSAAP, the user can get the recommended capacity of the reservoir to its location, consumption and ability to capture the rain. This program can also help the user realize the initial investment and the payback period associated with the respective RWHS. In the application of this tool, was study the implementation of a RWHS in cities of different regions of Portugal mainland in order to understand its viability in different conditions. It was studied the use of a RWHS that supplies just one dwelling unfamiliar house and has also been studied the use of a RWHS which supplies a set of four dwelling unfamiliar houses in order to benefit from a larger dimension. Through simulations performed on PSAAP, it is concluded that the higher the level of consumption, the cost of water consumed and precipitation available, the lower is the payback period.

碩士
國立臺灣海洋大學
河海工程學系
107
Due to global climate change, the United Nations treats rainwater harvesting systems as an adaption alternative toward water shortage problem. In domestic, Water Resources Agency, Ministry of Economic Development, has listed rainwater harvesting as an alternative new water resources in the water law. But, research in the subject of economic assessment of rainwater harvesting systems is rare. The purpose of this study is to establish the economic assessment framework of rainwater harvesting systems and apply this framework to the cases completed in 2018 in the project titled Smart Management in Water Resources and Water Conservation Technology (107). These results can be used as a reference for the government in promoting and installing rainwater harvesting systems in the future. In the study, the life cycle base concept is used to calculate the benefits and costs in the stages of system construction and operation. For calculating the benefit-cost analysis, the Net Present Worth, the Benefit/Cost Ratio and Payback Period methods are used to establish the economic benefit assessment framework of rainwater harvesting systems. The cost part can be divided into "direct" and "indirect" costs of the rainwater harvesting systems. Direct costs include facilities of rainwater collection, transport, storage, pump, treatment, monitoring etc. Indirect costs include business tax, air pollution tax, supervision service fees etc. The benefits part can be divided into "direct" and "indirect" benefits of the rainwater harvesting systems. Direct benefits include water saving fees and sewage discharge reduction fees. Indirect benefits include electricity saving and carbon emission reduction fees. For those cases, no monitoring rainwater usage data is collected and calculating the theoretical rainwater usage is laborious due to large number of cases. Therefore, in the study, figures and tables for relationship between average number of rainwater storage use vs. water storage volume and water supply reliability vs. water storage volume for selected roof areas, rainwater demand and areas are constructed to estimate the amount of rainwater use. Finally, the sensitivity analysis is carried out by increasing selected percentage of current water price and wastewater discharge fee to explore the variation of benefit/cost analysis. For the base case, the unit price for calculating benefits is listed as followings: unit price of water equals NT$ 7.35 per m3, unit sewage discharge fee equals NT$ 5 per m3, unit electricity fee equals NT$ 4.27 per KWH and unit price for carbon emission equals NT$ 388 per ton. From the results, 41 cases with a benefit/cost ratio between 0.01 and 0.50, 21 cases with a benefit/cost ratio between 0.51 and 1.00, 14 cases with benefit/cost ratio is greater than 1. The average payback period is 37.04 years. For carrying sensitivity analysis, water price was raised to between NT $ 17 and 22 per m3 and the wastewater discharge fee was raised to between NT$ 11 and 14 per m3and the electricity fee and unit price of carbon emission charges remained unchanged. The results show that 11 cases with a benefit/cost ratio between 0.01 and 0.50, 18 cases with benefit/cost ratio between 0.51 and 1.00, 44 cases benefit/cost ratio greater than 1. The average payback period is 29.4 years. Therefore, as price of water, wastewater, electricity increase, rainwater harvesting system will become more attractive and vital.

博士
國立臺灣海洋大學
河海工程學系
103
The average annual available water resource per capital in Taiwan is 1/5 of the world’s average. Water shortage problem becomes worse because water demand increases along with rapid urban development. To increase water supply, rainwater harvesting has been adopted as an alternative water resources by Water Resources Agency, Ministry of Economic Affairs. Also, rainwater harvesting technology has been included in the water resources indicator which is one of the evaluation indicators in green building rating system published by Architecture and Building Research Institute, Ministry of Interior. However, the information of amount of rainwater available nationwide and definition of rainwater potential are not available currently. Traditionally, storage volume of rainwater harvesting is determined using rainfall data from rainfall station without considering the regional scale. In addition, increased impervious area in urban area will alter surface runoff which affects water supply, stormwater, water quality and mico-climate in urban area. To restore the healthy and nature water cycle in urban area, reducing the impervious area is needed. The purpose of this study is to start a universal definition of rainwater potential, establish the mainframe for estimating the rainwater potential, establish the regional and dimensionless design curve for rainwater storage volume, and set up a stormwater management strategy for reducing impervious area in urban area. There is no universal definition of rainwater potential worldwide. For considering the influenced factors including characteristics of building, hydrology, economics and ecology to rainwater potential, three different categories of rainwater potential are suggested: theoretical potential, available potential and environmental bearable potential. To estimate the rainwater potential nationwide, four major steps are recommended: (1) using both average annual 10-day rainfall distribution for rainfall stations and administration boundary to classify region into rainfall homogeneous sub-regions; (2) with the assistance of GIS and land use data base to estimate the total roof area in each sub-region; (3) estimating the optimal rainwater substitution ratio for equivalent building in each sub-region for selected water demand and rainwater supply reliability; and (4) estimate the environmental bearable rainwater potential by selecting different percentage of total roof and its impact to downstream stream flow. Through these steps, annual theoretical rainwater potential reaches 1,763.20×106 m3; available rainwater potential is 1,168.73×106 m3 and; environmental bearable rainwater potential is 116.87×106 m3 with 10% of total roof area used. Determination of rainwater storage volume is the major component in rainwater harvesting system design. Rainfall data is the most significant factor in determining rainwater storage volume. However, such information is available only at a few locations, and in the majority of catchments, particularly those at remote locations, the data are normally extremely scant. For areas with incomplete or no rainfall data, storage sizing is difficult for rainwater harvesting system design. This research selects the northern part of Taiwan as the study area and sets up the regional and dimensionless design curves for estimating rainwater storage volume. These curves consider the factors of water demand, effective roof area and annual rainfall. Storage volumes estimated from these curves are compared with those by methods of simulation using single rainfall data. The absolute difference percentages between estimated and simulated values are less than 20% which is acceptable in storage volume estimation. The storage volumes estimated by those dimensionless curves are also compared with those values obtained by method used in green building evaluation manual. Based on the dimensionless curves, nomograms in four sub-region were constructed for designing rainwater harvesting system at a rainwater supply reliability of 95%.The methodology developed herein can be used effectively for the preliminary design of a rainwater harvesting system and for overcoming the difficulties faced in designing a rainwater harvesting system without rainfall data and with incomplete rainfall data. To develop the evaluation strategy for improving the imperviousness in urban area, image processing is used to differentiate the green coverage ratio in the urban areas firstly. Then VIKOR method for multiple attribute decision making will be used to determine the priority of improvement of imperviousness among metropolis plan districts in urban area. Decision indicators include non-green coverage ratio, population density, land area of schools and land area of parks in decision making. For those priority improvement districts, further detailed image differentiate process is needed to generate the goal and strategy for imperviousness improvement. Twenty districts in New Taipei city are selected as the study area. From the results, Tai-Shan, Shu-Lin, Hsin-Zun, Shi-Chi and Tan-Shwei districts are selected as the first priority to improve the imperviousness. The suggested short-term goal of improvement of imperviousness is 9% and middle term ranges between 16% - 18%. For long-term, it ranges between 41% - 46%.

碩士
國立臺灣科技大學
化學工程系
101
This study aimed to investigate the effects of typhoon and dust storm on harvested rainwater quality. Total of 192 rainwater samples were collected from two rainwater harvesting systems (RWHSs) on a campus in northern Taiwan between January 2011 and April 2013. There were five typhoons and one dust storm invaded Taiwan during the period. Harvested rainwater was analyzed, including pH, electrical conductivity (EC), turbidity, alkalinity, total organic carbon (TOC), acute biotoxicity test, concentration of 13 metals (Al, Ca, K, Mg, Na, Cu, Fe, Mn, Zn, Cd, Cr, Pb and Ni) and 3 anions (Cl-, SO42- and NO3-). In addition, multiple-tube fermentation was included fordetection of total coliforms (TC) and fecal coliforms (FC). For pilot-scale RWHS, results of harvested rainwater of dust storm showed higher pH, turbidity, TOC, Na, Mg, Ca, Cl-, NO3- and SO42- than normal rainwater. On the other hand, in the case of typhoon rainwater, due to strong wind and dilution effect, most of the ion concentrations in harvested rainwater were lower than normal rainwater. However, lethal concentration 50% (LC50) and TC in harvested rainwater during dust storm and typhoon were not significantly different from normal rainwater. In terms of ultraviolet disinfection on harvested rain from full-scale RWHS, complete inactivation occurred within 21 and 63 s by using 254 nm wavelength UV light at intensity of 1231 and 224 (μW/cm2), respectively. However rainwater flowed into temporary tank with pollutant on rooftop and sports ground resulted in higher TC and FC on rainy day, therefore, it was necessary to increase UV light intensity or extend exposure time on rainy day to achieve complete inactivation.

Dissertação de mestrado em Engenharia Urbana
No actual contexto em que as relações entre os seres humanos e os recursos naturais são cada vez mais relevantes em razão do aumento populacional no mundo e da mudança dos hábitos de consumo dos seres humanos - com aumento da exploração destes recursos, em especial a água - é essecial que sejam estudadas formas alternativas de obtenção e consumo destes recursos sob a ótica sustentável. Dentre as possibilidades de mundanças em relação ao uso de água no dia-a-dia das populações está o aproveitamento de águas pluviais, que é um método muito antigo, com registos de utilização a mais de 5000 anos. A adoção de métodos alternativos de abastecimento de água, entretanto, pode acarretar em impactes nos sistemas de distribuição de água já existentes, que por isso devem ser estudados para que se possa tomar atitudes em relação a possíveis constrangimentos causados por esta mudança de comportamento. O objetivo desta dissertação é analisar a influência que a adoção de métodos alternativos de abastecimento de água, como os Sistemas de Aproveitamento de Águas Pluviais - SAAP, podem causar numa rede pública de distribuição de água potável; mais especificamente avaliar quais as influências da redução do consumo de água da rede pública – causada pelo aumento do uso de SAAP – nas velocidades médias nas condutas de água, nas pressões dinâmicas nos nós da rede, e também na concentração de cloro residual nos nós desta rede. Utilizou-se como caso de estudo a rede que abastece o Lago Norte, Brasília-DF Brasil. Os resultados das simulações demostram que quanto maior o uso de SAAP (e menor consumo de água da rede pública) menores as velocidades mínimas e máximas nas condutas, maiores as pressões dinâmicas mínimas e máximas nos nós e menor a quantidade de CRL nos nós da rede. Portanto, o uso de sistemas alternativos de abastecimento pode causar alterações no funcionamento da rede pública de abastecimento de água, que por este motivo devem ser monitoradas. Sugere-se a realização de alterações à rede, já que as mudanças dos valores destes parâmetros provocadas pela adopção de SAAP podem afetar os aparelhos hidráulicos da rede, assim como a qualidade da água fornecida pelo sistema público tradicional. É apresentada uma nova configuração da rede simplificada, com o uso de válvulas redutoras de pressão e de pontos de cloragem ao longo da rede.
The relations between humankind and natural resources are, in actual context, getting more relevant because of the increasing number of populations in the world and changes about people consumption habits – with the increase of the exploration of these resources, especially water – is essential that alternative ways of obtaining and consuming these resources have to be studied looking for sustainable practices. Rainwater harvesting is one of the alternatives about changing the way people deal with water daily, and it is an old method with registers of more than 5000 years old. Adopting alternatives methods of water supply, however, can cause impacts at the public water supply network, and it must be studied to try to solve possible problems these changes of behavior can cause, if necessary. The objective of this master thesis is to analyze the influence of the adoption of alternative methods of water supply, such as rainwater harvesting systems - RWS, can cause at the public water supply network; more specifically, the influence of the reduction of water from the public system – caused by the increase of rainwater harvesting – can occur relatively at the average velocity in the pipes, at the dynamic pressures at the nodes as well as the variations of the free residual chlorine at the nodes of the network. It was used as a case of study the water network that supplies the Lago Norte, Brasília-DF Brazil. The simulation’s results demonstrate that as much as the use of RWS increase (and the water from public supply network decrease) lower the minimum and maximum velocities in the pipes are, higher the dynamic minimum and maximum pressure at the nodes are, and lower the FRC quantities are at the network nodes. Therefore, the use of alternative systems of water supply can cause disturbs at the public water supply network, so it has to be monitored, and modification plans for this network must be done, whereas the changes of the parameters values provoked by the use of alternative systems can affect the hydraulic equipment of the network, as well as the quality of the water offered by traditional public system. A new network is presented after adding pressure reduction valves, as well as new chlorination points throughout the network.