Submitted by Renata Lopes (renatasil82@gmail.com) on 2015-12-07T12:18:46Z No. of bitstreams: 1 catarinamattosbarbosadeoliveira.pdf: 10196740 bytes, checksum: bcd6015af6ac1fe57d36299302b84bbf (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2015-12-07T21:40:03Z (GMT) No. of bitstreams: 1 catarinamattosbarbosadeoliveira.pdf: 10196740 bytes, checksum: bcd6015af6ac1fe57d36299302b84bbf (MD5) / Made available in DSpace on 2015-12-07T21:40:03Z (GMT). No. of bitstreams: 1 catarinamattosbarbosadeoliveira.pdf: 10196740 bytes, checksum: bcd6015af6ac1fe57d36299302b84bbf (MD5) Previous issue date: 2015-01-26 / Sabendo-se que grande parte da população mundial vive em áreas geologicamente desfavoráveis e desprovidas de qualquer planejamento, esta dissertação apresenta uma pesquisa cuja temática é atual e de grande relevância no contexto urbano. Tal fato foi e continua sendo determinado pelo crescimento acelerado do processo de urbanização aliado à falta de controle e planejamento adequados ao uso do solo urbano. O objetivo principal deste trabalho é propor alternativas para a gestão das águas pluviais em comunidades de risco, estabelecidas em assentamentos precários, localizadas em áreas com infraestrutura insatisfatória e ambiente degradado, que contribuam para a redução de riscos da comunidade. A metodologia aplicada inicialmente é baseada em uma revisão bibliográfica multidisciplinar, que explora o contexto histórico, a formação, a natureza, as relações, os valores sociais e políticos, os conceitos, os riscos dos desastres naturais. Num segundo momento e tendo como base os conceitos teóricos sobre as soluções técnicas para drenagem superficial das águas pluviais e as condicionantes teóricas que validam essas soluções, foi aplicada uma nova metodologia através da elaboração de uma matriz de decisão adaptada da Metodologia para Desenvolvimento do Produto. Através da seleção de conceitos de produto, o somatório dos valores adotados para as condicionantes da matriz de decisão determinou o produto ou o conjunto de produtos passíveis de serem aplicados na gestão das águas pluviais em encostas acentuadas. Após a identificação das soluções viáveis, foi elaborada uma proposição de intervenção em local específico, tendo como base para a seleção da região, os dados das áreas de grau de risco a deslizamentos determinados pela Subsecretaria de Defesa Civil do município. / Given that much of the world's population lives in geologically unfavorable areas and devoid of any planning, this dissertation presents a research whose theme is current and highly relevant in the urban context. This fact has been and continues to be determined by the rapid growth of urbanization together with the lack of control and planning appropriate to the use of urban land. The main objective of this work is to propose alternatives for the management of stormwater at risk communities, established in slums located in areas with poor infrastructure and degraded environment, contributing to the community risk reduction. The methodology applied is initially based on a multidisciplinary literature review, which explores the historical background, training, nature, relationships, social and political values, concepts, the risks of natural disasters. Secondly, and based on the theoretical concepts of technical solutions for surface drainage of rainwater and the theoretical conditions that validate these solutions was applied a new methodology by developing a tailored decision matrix methodology for product development. By selecting product concepts, the sum of the values adopted for the constraints of decision matrix determined the product or set of products which can be applied in the management of rainwater on steep slopes. After the identification of viable solutions, an intervention proposition in a specific location was drawn up, taking as a basis for selection of the region, the data of risk degree of areas to mudslides determined by the Civil Defence Secretariat of the municipality.

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.

The intent of this project is to provide tools for public administrators to implement and evaluate the cost of an alternative on-site residential water supply using rainwater harvesting and greywater reuse in their jurisdiction. These tools are then applied to the city of San Luis Obispo (SLO), California as a case study to demonstrate how rainwater harvesting and greywater reuse could be implemented to supply all residential potable and non-potable water needs, completely replacing the current centralized publicly-managed water system. Further, energy and direct fiscal costs of the alternative system are compared with the current system. A cost analysis is crucial given that sustainability is heavily linked to appropriately valuing a resource and increasing the visibility of same to the public. Pursuing sustainable water supply options is particularly important given critical water shortages and the need to decouple the energy/water equation in pursuit of reducing energy use and greenhouse gas (GHG) emissions. A decision tree and other tools were developed as part of this project for use by public administrators to determine the site-specific scope of an alternative residential water supply system. For example, a key question is the capacity of such a system to supply both potable and non-potable water needs. These tools were applied to single family (SF) residences in the case study city of SLO and resulted in an alternative residential system capable of completely substituting for public water supply. Implementation requires a major adjustment of indoor water demand from the SLO average of 55 gallons per capita per day (gpcd) to a ‘best practice’ water conservation mode of 27 gpcd, including a greywater reuse system for irrigation and toilet flushing. With demand held constant, the costs of the alternative on-site residential water supply system were then compared to the costs of the current centralized public water system for both the municipality and the consumer in SF residences in SLO. The public water supply costs were based on overall budgeted costs, including implementing a new project the city is partially financing for conveying Nacimiento Reservoir water to SLO. Consumer-billed costs include expected price increases proposed for the next year by the City largely due to the addition of the Nacimiento project. The volumetrically apportioned municipal water supply cost ($0.0049/gallon) is 37% lower than that billed to the consumer ($0.0078/gallon), but the wastewater processing cost for the City ($0.0125/gallon) is 39% greater than that billed to the consumer ($0.0076/gallon). Thus the combined water supply and wastewater processing costs for the City are only 4% greater than that billed to residential customers. It is notable that the City intends to significantly increase water prices billed to customers over the next several years which would shift the cost analysis in favor of the alternative system. The alternative system costs were based on operating costs (such as electricity) and the cost of the installed components of the system averaged yearly according to the life of the parts (10-50 years). The municipal cost for water supply ($0.0049/gallon) was 55% less than the cost for the alternative system ($0.0111/gallon), but the cost savings of wastewater processing using the alternative system ($0.0086/gallon) is 31% less than the municipal cost ($0.0125/gallon). The alternative systems savings are mostly a result of on-site greywater reuse for irrigation and indicate the scope of the immediate fiscal benefit to the municipality to substitute residential greywater systems for current public wastewater services. To calculate the overall cost difference in terms of both water supply and wastewater costs, the total costs used are as if all SF residences in SLO used the system. Overall, the municipal costs for combined water supply and wastewater processing ($4,137,598/yr) were 20% less than the alternative decentralized on-site system ($5,376,735/yr). The cost to the consumer for current water supply through the public water system ($0.0078/gallon) is 29% lower than the proposed alternative system ($0.0111/gallon). The wastewater processing cost to the consumer ($0.0076) is also 11% less than that of the alternative system ($0.0086/gallon). On this basis, the consumer cost using expected billing rates ($4,137,598) is 23% lower using the public water system than the cost of the alternative system ($5,376,735). Expected water and sewer rate increases may skew these results in favour of the alternative system where it is viable for the consumer to completely replace their water system and remove their household off the public water system to their financial benefit. The overall energy for water supply and wastewater processing used by the public water system was 34% lower (1,216,849 kWh/yr) than the alternative system (1,855,894 kWh/yr). The alternative on-site system’s electrically-driven pump is mostly responsible for this energy use and could be virtually eliminated by using gravity feed, as is common in many parts of the world currently using rainwater harvesting technology. Solar energy is also an effective solution to eliminate fossil-fuel based electricity. From a fiscal perspective, the alternative system costs are inflated given that an expected drop in supply cost would likely ensue with the economies of scale gained if an entire city was purchasing equipment for the alternative systems. This could override the results of the study showing the alternative system’s 20-23% higher fiscal cost than current public water system. Considering the ‘no fossil-fuel’ energy alternatives and the expected significant drop in supply cost with large scale purchasing, the alternative system provides a promising alternative residential water supply for SLO.

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.

Yes / This paper presents a study to assess the roof-harvested rainwater (RHRW) in the Ikorodu area of Lagos state, Nigeria, and recommends guidance to minimise the health risk for its households. The types, design and use of rainwater harvesting systems have been evaluated in the study area to inspect the human risk of exposure to Escherichia coli (E. coli). To achieve these objectives, a detailed survey involving 125 households has been conducted which showed that 25% of them drink RHRW. Quantitative microbial risk assessment (QMRA) analysis has been used to quantify the risk of exposure to harmful E. coli from RHRW utilised as potable water, based on the ingestion of 2 L of rainwater per day per capita. Results have revealed that the maximum E. coli exposure risk from the consumption of RHRW, without application of any household water treatment technique (HHTTs) and with application of alum only, were 100 and 96 respectively, for the estimated number of infection risk per 10,000 exposed households per year. This estimation has been done based on 7% of E. coli as viable and harmful. Conclusively, it is necessary that a form of disinfectant be applied to the RHRW before use.

The project "Feasibility of evaporative cooling and toilet flushing using rainwater in a public building" combines rainwater harvesting with the evaporative cooling technology and toilet flushing and explores the practicality and viability of implementing this innovative system in the city of Gothenburg, Sweden. This study comprehensively investigates various aspects related to water and energy, and the entire system is computationally modelled using the Equation Engineering Solver (EES) software. The primary objective of the project is to assess the feasibility of utilizing harvested rainwater either for employing evaporative cooling for temperature control or for flushing toilets in a commercial building. By leveraging these sustainable practices, the project aims to reduce both water consumption and energy usage, thereby promoting environmental conservation and decreasing the ecological footprint. The study involves an in-depth analysis of several key aspects. Firstly, the local climate and rainfall patterns in Gothenburg are examined to evaluate the availability and adequacy of rainwater as a resource. Secondly, evaporative cooling technology is extensively investigated to determine its efficiency in cooling indoor spaces. The thermal dynamics and cooling potential of the system are analyzed, taking into account factors such as temperature differentials, humidity levels, and air circulation. The Equation Engineering Solver software is employed to simulate and compute the system's performance under varying conditions, allowing for predictions and optimization. For doing that, three cases with different conditions concerning the priorities of cooling and flushing necessities and the water volume in the two existing tanks in the installation have been developed in order to analyse the benefits they would bring in terms of energy and water savings. The comprehensive analysis of the technical and environmental feasibility of the three cases of study provides some advantageous results. Starting by analyzing the water aspect, in the first case, the one that prioritizes the cooling aspect while the water to fill the toilet flushing necessities is provided just if in the second tank there is any water left, a total of 37% and 10% of the requirements would be filled for the AHU and the toilet flushing respectively. Secondly, the case that still prioritizes the cooling demand but water for toilet flushing is provided as long as the storage tank is half full, meets 69% and 8% of the demand of the AHU and the flushing respectively. Laying aside the flushing aspect considering simply cooling in the third case, 75% of the supply within the AHU is met. When it comes to the thermal part, on the one hand, fractions provided by the new evaporative system are 22%, 32% and 49% respectively. This is due to the fact that almost every month in the three cases studied aims for extra cooling since the system does not hold the quantity of water required and therefore, an extra supply from the current cooling device is needed. Nevertheless, the system brings energy savings of 1005.3, 1510.4 and 2022.4 kWh per year. Furthermore, the energy consumption, in the three cases is very similar and low. The conclusions of the project, from a technical point of view, despite considering the fact that the requirements are not entirely met with actual medium contribution fractions either within the water and cooling aspects, with the existing water availability, the tanks and the pumps sizing and the existing AHU, the system is reliable and is capable to perform properly. Therefore, it can be concluded that it is technically feasible. Concerning the environmental feasibility, the key point of the study, depending on the case, the system would bring different savings. On the one hand, the water savings are 40.3, 47.0 and 8.2 m3 yearly for every case respectively, concluding that the second case is the one that would entail the highest water savings to the system. On the other hand, the energy savings hold values of 1005.3, 1510.4 and 2022.4 kWh annually, with the third case bringing the greatest value. Consequently, the three cases can be considered environmentally feasible since all of them achieve the overall objective of the project, the reduction of water and energy usage. However, depending on the savings’ preferences, either the second case with the highest reduction in water or the third case with the highest decrease in energy could be considered the best ones. From a general point of view, the second case could be the most suitable to set since it is the one that saves more water and moreover, it brings an energy reduction between the average values in the first and in the third case. These outcomes provide valuable insights and inform decision-making processes for the successful implementation and adoption of the system, and they guide future implementation strategies and contributions to sustainable urban development. / Projektet " Genomförbarhet för evaporativ kylning och spolning av WC med regnvatten " kombinerar insamling av regnvatten med evaporativ kylningsteknik och toalettspolning och utforskar möjligheten implementera detta innovativa system i Göteborgs stad, Sverige. Denna studie undersöker aspekter som vatten och energi. Systemet är modellerat med hjälp av programvaran Equation Engineering Solver (EES). Det primära syftet med projektet är att bedöma genomförbarheten av att använda uppsamlat regnvatten antingen för att endast evaporativ kyla för temperaturkontroll i en kommersiell byggnad eller för att spola toaletter med. Genom detta syftar projektet till att minska både vattenförbrukning och energianvändning, och därigenom främja miljö och minimera det ekologiska fotavtrycket. Studien gör en djupgående analys av flera nyckelaspekter. För det första undersöks det lokala klimatetoch nederbördsmönstren i Göteborg för att utvärdera tillgängligheten och tillräckligheten av regnvatten som resurs. För det andra undersöks tekniken för evaporativ kylning för att fastställa dess effektivitet vid kylning av inomhusutrymmen. Systemets kylningspotential analyseras med hänsyn till faktorer som temperaturskillnader, fuktighetsnivåer och luftcirkulation. Programvaran Equation Engineering Solver används för att simulera och beräkna systemets prestanda under varierande förhållanden, vilket möjliggör exakta förutsägelser och optimering.För att göra det har tre fall med olika förutsättningar avseende prioritering av kyl- och spolningsbehov samt vattenvolymen i de två befintliga tankarna i anläggningen testats för att analysera deras respektive energi- och vattenbesparingar. Utifrån vattenaspekten kunde det första fallet, den som prioriterar kyla medan vattnet för att fylla toalettens spolningsbehov tillhandahålls om det finns något vatten kvar i den mindre tanken, fylla totalt 37% och 10% av vattenbehovet för evaporativ kyla respektive toalettspolning. För det andra fallet, prioritering av kylbehovet men vatten för toalettspolning tillhandahålls så länge lagringstanken är halvfull, tillhandahåller 69 % och 8 % av behovet av evaporativ kyla respektive spolningen. För det tredje fallet, där allt vatten avses användas till evaporativ uppfylls 75 % av vattenbehovet. När det gäller den energimässiga aspekten tillhandahålls 22 %, 32 % respektive 49 % av det kylbehovs som krävs. Detta beror på att det under de tre studerade månaderna inte finns tillräckligt med vatten och därför krävs extrakyla. Systemet ger ändå en energibesparingar på 1005, 1510 respektive 2022 kWh per år.Projektets slutsatser, ur teknisk synvinkel, är att trots att man beaktar att hela behovet inte helt uppfylls vare sig inom vatten- och kylaspekterna, med den befintliga vattentillgången, tankarna och pumparnas dimensionering och den befintliga AHU:n är systemet pålitligt och kan fungera korrekt. Därför kan man dra slutsatsen att det är tekniskt genomförbart. När det gäller den miljömässiga genomförbarheten, den viktigaste punkten i studien, skulle systemet medföra olika besparingar beroende på fallet. Å ena sidan är vattenbesparingarna 40,3, 47,0 och 8,2 m3 årligen för varje fall, således är det andra fallet är det som skulle medföra störst vattenbesparing för systemet. Å andra sidan är energibesparingen störst för det tredje fallet. Följaktligen kan de tre fallen anses vara miljömässigt genomförbara eftersom de alla uppnår projektets övergripande mål, att minska vatten- och energianvändningen. Men beroende på besparingarnas preferenser kan antingen det andra fallet med den högsta minskningen av vatten eller det tredje fallet med den högsta minskningen av energi anses vara det bästa. Ur en allmän synvinkel kan det andra fallet vara det mest lämpliga att ställa in eftersom det är det som sparar mer vatten och dessutom ger det en energireduktion mellan medelvärdena i det första och i det tredje fallet. Slutligen ger dessa resultat ger värdefulla insikter hur framtida liknande system kan utformas för att bidrag till hållbar stadsutveckling.

The Master‘s thesis addresses sanitation installation and gas installation in the indoor swimming pool in Litomyšl. The theoretical part focuses on the use of greywater and rainwater as service water. The thesis includes the design of several variants with their assessment. The project for construction is also part ofthe thesis.

Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Lee R. Skabelund / Stormwater management is typically approached from different perspectives by practicing professionals. As such, stormwater planning/design is not always completed as a multi-disciplinary coalition of experts using holistic and synergistic methods. For a number of years, engineers and design professionals, particularly landscape architects, have been employing various strategies and techniques to address on-site stormwater management in terms of water quality and quantity. There is increasing awareness that in order to create solutions that are effective over both the short and long-term a landscape architect’s approach needs to account for the health, safety and welfare perspectives carried by engineers, the unique aspects of particular project sites, their surroundings and bio-regional context, as well as the perceptions of clients, other key stakeholders, and the broader public. This research investigates the various criteria integral to developing an analytic framework for ecologically-appropriate stormwater planning/design (Sustainable Stormwater Evaluation and Site Assessment or SSWESA). SSWESA is proposed as a type of decision-tree for site analysis of sustainable systems pertaining to stormwater. Using the SSWESA process is expected to help researchers and professionals make better planning and design decisions as they select and implement appropriate best management practices (BMPs) for a given site and context. My intent in developing SSWESA is to help designers assess existing and potential stormwater functions at the site scale in order to promote sustainable planning and design based upon the important principle: “First, do no harm”. It is also my intent to promote further research related to sustainability by providing references and sources from experts in the various fields related to ecologically-based stormwater management. A review of the literature related to ecological factors relevant to low impact stormwater management assisted in the development and refinement of the criteria for stormwater assessment and evaluation. In this report, the SSWESA framework is tested on a public school property in Manhattan, Kansas to demonstrate how the framework is applied and to understand the questions and issues that arise from its use.

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

L'objectif de ces travaux est de contribuer à augmenter la connaissance sur la réutilisation des eaux de ruissellement de toiture. Une maison individuelle située en zone rurale et équipée d'une toiture en tuiles, et un bâtiment collectif situé en zone périurbaine avec une toiture terrasse bitumée, ont été étudiés. Les eaux de pluie collectées sont réutilisées dans l'habitat pour l'alimentation des chasses d'eau. Un suivi analytique a permis l'étude de la qualité de l'eau en plusieurs points des systèmes. Les eaux stockées sont clairement non potables et révèlent une contamination microbiologique très variable. Des pathogènes ont été quantifiés à plusieurs reprises. La qualité de l'eau distribuée ne peut donc pas être garantie au cours de l'année, d'où la recommandation d'une désinfection de l'eau avant distribution. Un suivi hydraulique a permis de déterminer les volumes d'eau potable substitués et les taux de couverture de besoins en eau. Un modèle du comportement hydraulique a été développé puis utilisé pour discuter le dimensionnement des cuves. En présence d'une désinfection, les installations ne sont économiquement pas rentables. En l'absence de désinfection, le bilan économique est positif mais la période de retour sur investissement supérieure à la durée de vie de l'installation. Une première analyse de cycle de vie a été réalisée pour comparer les deux échelles étudiées. Dans les deux cas, les processus les plus impactants sont liés aux consommations électriques de l'éventuelle désinfection ultra-violet et des pompes. En présence d'une désinfection, l'échelle du bâtiment collectif présente des impacts plus faibles. Une deuxième analyse de cycle de vie a été réalisée pour étudier la pertinence de la substitution de l'eau du réseau d'eau public par de l'eau de pluie à l'échelle d'un particulier. Elle n'est pas probante d'un point de vue environnemental. / The aim of this work is to contribute to knowledge on roof runoff reuse. A private house located in rural area with a tiled sloping roof and a research building located in suburban zone with a bituminous flat roof were studied. The collected rainwater is reused for toilet flushing. An analytical monitoring allowed the study of water quality in several points of the systems. Stored rainwater is clearly non drinkable and reveals a very variable microbiological contamination. Pathogenic agents were quantified on several occasions. Distributed water quality cannot thus be guaranteed over the year and a disinfection before distribution is recommended. A hydraulic follow-up made it possible to determine substituted volumes of drinking water by collected rainwater and water saving efficiencies. A model of the hydraulic behaviour of systems was developed then used to discuss dimensioning of the tanks. In the presence of disinfection, the installations are economically not profitable. In the absence of disinfection, the economic assessment is positive but the payback period is longer than the lifespan of the installation. A first life cycle assessment was carried out to compare the two studied scales. In both cases, the more impacting processes are related to electricity consumptions of possible ultra-violet disinfection and the pumps. In the presence of disinfection, the scale of the building presents weaker impacts. A second life cycle assessment was carried out to study the relevance of the substitution of drinking water by rainwater on a private individual scale. It is not convincing of an environmental point of view.