Dissertations / Theses on the topic 'Sustainable urban drainage system'

Sustainable Urban Drainage Systems (SUDS) is a generic term that refers to various measures aimed at minimising surface runoff (and consequent flooding and pollution problems) from urban catchments. SUDS technologies include local infiltration, storage and storm-water re-use devices. Although there is considerable international evidence of the successful incorporation of SUDS technologies in new developments, there is very little indication of the extent to which they represent a viable rehabilitation option for retrofit applications to problem urban catchments in the UK. It is believed that uncertainties about the design, hydraulic performance and cost of retrofit SUDS schemes, as well as some regulatory issues, have prevented UK engineers from exploiting the full potential of this approach. This thesis presents two case studies in which retrofit SUDS have been evaluated against 'conventional' (i. e. in-sewer) drainage rehabilitation schemes. The case studies relate to the City of Leeds in Northern England, UK. In both cases it was found that SUDS technologies were viable, both in terms of hydraulic performance criteria (number and volume of CSO spills or flooding events) and in terms of comparative construction costs. Novel procedures were developed for evaluating hydraulic performance and SUDS scheme costings. The identification of the most cost-effective from all feasible SUDS technologies for a given location is not straightforward. This thesis, therefore, proposes a design methodology for retrofit SUDS. The methodology comprises a decision making model (flow chart) that indicates whether SUDS-based approaches are likely to be viable, and cost-effective for a particular application. The flow charts make reference to SUDS design criteria (such as land-take, slope and infiltration capacity) and regulatory constraints (such as Building Regulations and local groundwater protection policies). Fundamental to the flow charts arc hierarchies that characterise urban surface type, the treatment train concept, the disposal mechanism, and cost.

Our planet stands before many great challenges, where climate change and urbanization are two of the major challenges. One of the challenges due to climate change is the increased amount of precipitation and of extreme rainfall, which creates a higher amount of stormwater within the urban areas and an increased risk of urban flooding. Urbanization and an increasing global population put pressure on the environment as more land is exploited and existing urban areas are further developed and densified. Urban areas are already under high pressure to handle the risks of climate change, therefore is climate change adaptation prominent to create more resilient and sustainable urban areas, where stormwater management is one of the challenges that need to be tackled. The aim of this study is to answers one main research question and three sub research question about enablers, barriers, and key factors regarding planning, designing, and implementing sustainable urban drainage systems in the built environment. The used methods are literature study research and multiple case study research. Five case study areas where studied to gather knowledge about areas that have implemented sustainable urban drainage systems. Lessons learned for each of the case study areas where gathered and connected to the literature and used to answer the research questions. The gathered knowledge from the literature and case studies where used to compile recommendations of how a sustainable urban drainage system could be planned and implemented at a pilot study area, which is Välsviken in Karlstad, Sweden. To be able to achieve a sustainable and resilient urban drainage system, that can handle the challenges of climate change and urbanization, it is important that the stormwater planning process is changing. It is crucial to implement facilities and systems that are sustainable, multifunctional, and flexible. The planning process needs to use planning and costing approaches that include flood mitigation and co-benefits, in the long-term and short-term simultaneously. Implementation of sustainable urban drainage systems also needs to be enabled in new areas or being retrofitted into already exploited areas. This could make it possible to create urban areas that are able to tackle the challenges of climate change and urbanization, and create multifunctional, sustainable, and flood mitigated urban areas.<br>Vår planet står inför många stora utmaningar, där klimatförändringar och urbanisering är två av dessa. En av utmaningarna med avseende på klimatförändringarna är den ökade mängden av nederbörd och extrema regntillfällen, vilka bidrar till större mängder dagvatten i urbana områden och en ökad risk för översvämningar. Urbaniseringen och det ökande antalet invånare globalt sätter press på miljön eftersom mer landyta exploateras och nuvarande urbana områden fortsätter att bebyggas och förtätas. De urbana områdena har redan stora utmaningar med att hantera riskerna med klimatförändringarna. Klimatanpassning är därför viktigt för att skapa mer resilienta och hållbara urbana områden, där dagvattenhanteringen är en av utmaningarna som behöver hanteras. Målet med denna studie är att besvara en övergripande forskningsfråga och tre underliggande forskningsfrågor om möjliggörare, barriärer och nyckelfaktorer gällande planering, design och implementering av hållbara urbana dagvattensystem i den bebyggda miljön.  Metoderna som användes var litteraturstudie och multipel fallstudie. Arbetet började med litteraturstudien och sedan genomfördes en fallstudie där fem områden som implementerat hållbara urbana dagvattensystem undersöktes. Lärdomar från varje område sammanställdes och kopplades samman med den andra litteraturen för att besvara forskningsfrågorna.  Utifrån litteraturen och fallstudierna sammanställdes rekommendationer för hur ett hållbart urbant dagvattensystem kan planeras och implementeras inom ett utvalt studieområde, vilket är Välsviken i Karlstad, Sverige.   För att åstadkomma ett hållbart och resilient urbant dagvattensystem, som kan hantera utmaningarna gällande klimatförändringar och urbanisering, är det viktigt att planeringsprocessen för dagvatten ändras. Det är viktigt att implementera anläggningar och system som är hållbara, multifunktionella och flexibla. Planeringsprocessen behöver använda planerings- och kostandsmetoder som inkluderar översvämningsanpassning och sidofördelar, både långsiktigt och kortsiktigt samtidigt. Man behöver också möjliggöra implementering av hållbara urbana dagvattensystem i nya områden eller anpassa områden som redan är bebyggda. Detta kan bidra till att skapa urbana områden som kan hantera klimatförändringarnas och urbaniseringens utmaningar, och skapa multifunktionella, hållbara och översvämningssäkrade områden.

Infiltration trenches and filter drains are the most common types o f sustainable urban drainage systems (SUDS) in Scotland. Despite their extensive use there has been only limited examination of their performance, with the general expectation that failure through lack of maintenance and poor detailing design would necessitate reconstruction within a limited time period. This research worked towards enhanced detailing and improved operation and maintenance of in-ground SUDS. It focused on information gained from on-site monitoring of three filter drain and three infiltration trench systems and combined the outcomes with information gathered from some 40 assessments of in-situ systems in Eastern Scotland. Performance results were produced using a newly developed scoring system, named the Schliiter Score, and results showed good performance at only 19% of systems; 19% were rated as poor and a high failure rate of 23% was discovered. Similar results were produce from a conventional environmental risk assessment identifying more than 30% of systems which require immediate mitigation measures to reduce their environmental risk. These findings give an indication of the varied performance of systems in Scotland and also show the need for knowledge enhancement in the field of in-ground SUDS. A main outcome from this research is a list of recommendations which are applicable to design engineers, developers, and authorities and contribute to achieving optimum long-term performance in terms of outflow quality and flow attenuation. A total number of 43 sites were investigated, the majority being systems located in small-to-medium size housing developments. The average age o f the sites was 4 years, the oldest and youngest being 10 and 1 years, respectively. Almost 75% o f all systems discharge to natural watercourses, disconnecting a significant amount of impermeable area from combined sewer systems. Catchment areas varied from 392m² to 200,000m², typically consisting of road and roof surfaces. High-level by-passes are used to ensure hydraulic performance and these were found at more than 50% of all systems. Maintenance programmes were generally not in place but this study showed that regular maintenance is vital for the longevity of in-ground SUDS. A significant number o f systems require major upgrading before they may be considered satisfactory and a maintenance appraisal is provided for each system. Hydraulic results from on-site monitoring showed good-to-satisfactory performance with flow volume reduction of 34-80% and peak flow reduction of 47-86%. The system’s design, treatment volume and soil permeability were found to be the main influence on the hydraulic performance. Simulation of flows significantly contributed to the conclusions drawn and hydraulic simulation was carried out for each o f the monitored systems. It was found that existing models did not represent in-ground filter systems adequately and an improved model was developed based on the finite-volume-method and Darcy’s law. This model, which uses the acronym FVD, was developed in collaboration with HR Wallingford Ltd and enables flow- simulation through gravel-filled SUDS. The FVD model was validated using on-site monitored data and an excellent agreement with observed data was achieved. Wallingford Software have proposed to include the FVD model in their next release o f Info works Version 6.5.

Water and energy are two of the most precious and essential resources which are inseparably connected; vital for the survival and well-being of humanity. Sustainable water resources and energy management emphasizes the requirement for a holistic approach in meeting the needs of the present and future generations. In order to indentify the needs and obstacles relating to water reuse and renewable energy initiatives, Hanson Formpave in partnership with The University of Edinburgh implement a five-year pilot project between May 2005 and June 2010. The research project addressed the use of sustainable urban drainage systems (SUDS) such as permeable pavements systems (PPS) and integration of renewable energy tools such as geothermal heat pumps (GHPs). The research uses the novel and timely urban drainage system and focuses on water quality assessment when incorporated with GHPs. Twelve-tanked laboratory scaled experimental PPS were evaluated at The King’s Building campus (The University of Edinburgh, Scotland) using different compositions. Variations in designs included the presence of geotextiles layers and geothermal heating/cooling applications. The experimental rigs were examined for a two year period (March 2008 to April 2010). Two types of urban stormwater were used in the analysis; (i) gully pot liquor and (ii) gully pot liquor spiked with Canis lupus familiaris (dog) faeces. This urban wastewater represented the extreme worstcase scenario from a storm event, which can occur on a permeable pavement parking lot. The pavement systems operated in batch-flow to mimic weekly storm events and reduce pumping costs. Six PPS were located indoor in a controlled environment and six corresponding PPS were placed outdoors to allow for a direct comparison of controlled and uncontrolled environmental conditions. The outdoor rig simulated natural weather conditions whilst the indoor rig operated under controlled environmental conditions such as regulated temperature, humidity and light. The project assessed the performance of these pavement rigs with the integration of ground-source heating and cooling, standalone PPS and the abilities for water quality treatment from a physical, chemical and microbiological perspective. The performance efficiency of the GHP was measured by the energy efficiency ration (EER) for steady state cooling efficiency and the coefficient of performance (COP) for the heating cycle efficiency. Findings from the combined PPS and GHP system and standalone systems were able to significantly lower levels for all physiochemical and microbial water quality parameters in the range of (70-99.99%) respectively. Outflow concentrations for all pavement systems met the European Commission Environment Urban Wastewater Treatment Directive (91/271/EEC). The presence of geotextiles resulted in a significant reduction of contaminants when compared to PPS systems without (p <0.05). Photocatalytic disinfection with titanium dioxide (TIO2) was applied to the effluent from PPS for further treatment and polishing of the stormwater. After the photocatalytic disinfection, the water met the requirements for the United States Environmental Protection Agency (US EPA) water recycling guidelines and the World Health Organisation (WHO) guidelines for potable water consumption with regards to microbial contamination. An Energy and temperature balance was developed for two PPS using a 4th order Runge-Kutta numerical method to model the heat fluxes and energy balance within the pavement system. Machine learning techniques such as artificial neural networks (backpropagatioin feed forward neural networks) and self-organising maps (SOM) were applied and successfully predicted the effluent concentrations of nutrients, biochemical oxygen demand (BOD) and microbial pollutants. The overall outcome of this research is a significant contribution to the development of a new generable of sustainable and eco-friendly pavements. The research project proves scientifically that PPS is one of the most appropriate systems for GHP installation and does not affect its efficiency for water pollutant removal.

The research presented in this thesis addressed the performance of Sustainable Urban Drainage Systems (SUDS) at three sites in Scotland - a porous paved car park and two swales. It is the first research to provide results for such systems in the UK and also the first direct comparison between SUDS and traditional systems in situ. The aim of developing guidance on effectiveness and synthesising design recommendations has been achieved with the integration of hydrological and water quality studies together with modeling. Monitoring data and information were analysed on both a site-by-site basis and as a comparison between sites. Hydrological and water quality data were collected at each site. Key hydraulic parameters examined include percentage runoff, initial runoff loss, peak flow reduction and lag time. The term Benefit Factor has been introduced as a volumetric measure used to summarise the hydraulic benefit gained by installing SUDS, as no comparable terminology has yet been used elsewhere. The water quality parameters include physical/ chemical, hydrocarbons and metals. All three sites had low levels of pollution with little scope for water quality improvement, however the changes in water quality did indicate the different processes occurring within the systems. Computer models were built for the porous paving installation and one of the swales, further to understand the processes of source control and to analyse the systems. Hydraulic capacity exceedence criteria were investigated using design storms, and finally the models were used to evaluate improvements to design detailing. The results of this research have shown that, despite being under-designed according to current guidance, all three sites performed very favourably. The performance of porous paving and swales can be similar depending on design and detailing. A number of design recommendations are made as a result of observations and sensitivity analysis, and these should be considered in conjunction with current guidance.

A study conducted by The Department of Environment Malaysia shows that there is an increase in numbers of polluted rivers. One problem is said to be due to indiscriminate dumping of wastes into the rivers. This phenomenon adversely affects the drainage capacities of rivers which then leads to more frequent occurrences of floods as well as an increase in the intensity of the floods. The issues are critical since 97% of the total water use originates from rivers. In Malaysia, 40-60% of water use comes from the domestic domain. Domestic wastewater gives an impact on the quality of water. Public involvement is very important in order to control the current water situation as public contributions to water issues are very significant. In daily activities, the public pollutes the drainage runoff unconsciously. Increasing urban population causes a massive impact on human activities, especially in a developing country like Malaysia. In Malaysia, urbanization has a lot of advantages for the economic sector. Therefore, development needs to be carried out in order to provide a range of facilities for the population. On the other hand, living in comfortable and convenient spaces has persuaded many people to renovate their houses. This then results in an increase in the number of impervious areas because housing developers only have to comply with providing 10% of open space. Developers usually choose to maximise the built-up areas to take full advantage of land use and this situation has resulted in an increase in surface run-off. This is in fact a major cause of flash floods. Natural filtration devices have been incorporated in Sustainable Urban Drainage System (SUDS) as a means of imitating natural hydrological processes. They are found to be more effective compared to the conventional drainage system, and delay filtration and run-off of surface water. SUDS not only improve the technical approaches of a drainage system, but also assists in `Best Management Practices' (BMPs). This includes management and maintenance together with better daily water usage. However, to assist the success of SUDS, public participation should be encouraged. The wider public and all stakeholders should have a better understanding of SUDS in order to allow them to get a clearer idea of their potential role. Improvement in the education system, frequent updates on information and training for maintenance workers are some of the actions that might influence the implementation of SUDS in Malaysia.

Purpose: Climate change and increased proportion of hard surfaces due to urbanization is causing problems with flooding. Although it has been known for a long time that traditional stormwater management needs to be complemented, progress towards Sustainable Drainage Systems, SuDS, is slow. Techniques to locally handle storm water are available for most situations, but there is a lack of knowledge and experience. The aim of this thesis is to present a proposal on how implementation of SuDS can be promoted in urban development projects in Jönköping municipality. Method: Using literature review, interviews, document analysis and observation a qualitative study was conducted in two urban development projects; Ekostaden Augustenborg in Malmö and Munksjöstaden in Jönköping. Findings: The majority of the stormwater management techniques available in Augustenborg have also been discussed in Munksjöstaden by Jönköping municipality. Only one third of the techniques which has been discussed will be realized. Jönköping municipality lacks clear goals and a vision that is integrated into the planning process, which can explain this. During the interviews the site conditions were presented as arguments to why SuDS is difficult to implement. However the analysis showed that it is the other conditions that are decisive, something that also the scientific studies indicated. In order to promote the implementation of SuDS general and project-specific actions were elaborated. Implications: The local plan is the municipality’s sharpest tool for control of the physical development and demands must be submitted in the local plan in order to promote SuDS. The municipality needs to reprocess a practice level and equate SuDS with traditional stormwater management in order to make relevant demands on developers. To promote the implementation of SuDS, the authors suggests that Jönköping municipality carry out a pilot project focusing on sustainable stormwater management in an upcoming urban development project. Limitations: Since the thesis only includes two projects, there is a limitation of the conditions treated. Since the other conditions and the recommended actions are based on the factors identified in a national survey, the applicability is considered to be good. Although the project-specific actions are based on Jönköping municipality, it is possible for other municipalities to apply the PDSA-wheel to the extent that is suitable for the municipality.<br>Syfte: Klimatförändring och urbanisering med ökad andel hårdgjorda ytor orsakar problem med översvämningar. Trots att det sedan länge är känt att den traditionella dagvattenhanteringen behöver kompletteras går utvecklingen mot Sustainable Drainage Systems, SuDS, långsamt. Tekniker för att ta hand om dagvattnet lokalt finns för de flesta situationer men det saknas kunskap och erfarenhet. Målet med arbetet är därför att presentera ett förslag på hur implementering av SuDS kan främjas i stadsbyggnads-projekt i Jönköpings kommun. Metod: Med hjälp av litteraturstudie, intervjuer, dokumentanalys och observation har en kvalitativ studie genomförts på två stadsbyggnadsprojekt; Ekostaden Augustenborg i Malmö och Munksjöstaden i Jönköping. Resultat: Majoriteten av de tekniker för dagvattenhantering som finns i Augustenborg har diskuterats även i Munksjöstaden från Jönköpings kommuns sida. Det visade sig dock att endast en tredjedel av det som diskuterats kommer att förverkligas. Detta kan bland annat förklaras av att Jönköpings kommun saknar tydliga mål och en vision som är integrerad i planeringsprocessen. Vid intervjuerna lyftes platsen förutsättningar fram som argument till varför SuDS är svårt att tillämpa. Analysen visade dock att det är de övriga förutsättningarna som är avgörande, något som även de vetenskapliga studierna pekat på. För att främja implementeringen av SuDS har därför generella och projektspecifika åtgärder riktade mot de övriga förutsättningarna utarbetats. Konsekvenser: Detaljplanen är kommunens skarpaste verktyg för att styra den fysiska bebyggelsen och för att främja SuDS är det därför viktigt att det finns krav i detaljplanen. Kommunen behöver upparbeta en praxisnivå och likställa SuDS med traditionell dagvattenhantering för att kunna ställa relevanta krav på exploatörer. För att främja implementeringen är författarnas förslag att Jönköpings kommun genomför ett pilotprojekt med fokus på hållbara dagvattenlösningar i ett kommande stadsbyggnadsprojekt. Begränsningar: Eftersom arbetet endast innefattar två projekt finns det en begränsning i vilka förutsättningar som behandlats. Eftersom de övriga förutsättningarna och de rekommenderade åtgärderna utgår från faktorer som identifierats i en nationell enkät-undersökning bedöms ändå tillämpligheten vara god. Även om de projektspecifika åtgärderna utgår från Jönköpings kommun, är det möjligt för andra kommuner att tillämpa PGSA-hjulet i den omfattning som passar den aktuella kommunen.

In recent times urban flooding has become more frequent and more complex due to the effects of increasing urban areas and climate change. In some established urban areas the existing drainage infrastructure is unable to cope with the volume of surface runoff and flooding events are more frequent, therefore new approaches to create more space for water within developments are required. This research was conceived in that context. It aims to investigate the potential for integrating green space planning with water planning and to develop a framework for the same in order to reduce the risk of flooding. An extensive literature review was carried out in the areas of urban planning, water planning, planning legislations, and issues related to integrating green space and water planning. The review identified the need for an inclusive framework which could integrate aspects of green space and storm water planning more holistically to achieve greater spatial planning efficiency. To satisfy this need, a conceptual framework was developed which took into consideration the opinions of various stakeholders. The conceptual framework included green spaced planning for SUDS, recreational and storm water indicators and a mechanism for integrated evaluation of SUDS for recreation and storm water management. The conceptual framework provided a joint approach where both engineers and planners will need to work together for the development of integrated storm water and green space plans. The framework showed processes for both disciplines and also indicates how spatial planning and water planning interfaced so that there was clarity of roles. In order to evaluate integrated plans, an ‘integrated evaluation tool’ was developed which uses indicators from both the areas of green space planning and water planning. The evaluation tool also contained a scoring system which can be used to select storm water management options with more recreational potential. The tool provides a mechanism to balance the requirements of recreation and storm water management so that more holistic solutions can be developed by teams of engineers and planners. The conceptual framework and the integrated evaluation tool were applied to two case study catchments. Results from the case studies showed the relationship of spatial planning and flooding. It further tested whether recreational aspects could be integrated into storm water planning. A number of drainage options were tested to show the application of the evaluation tool under various scenarios. This results of the research showed that the conceptual framework was appropriate in both case study areas even though the areas had different patterns of development. It is therefore proposed that the approach has potential for wider application in other geographical areas. Results from the two areas also showed that the integrated approach established in this research could enhance the recreational aspects associated with urban storm water management. The framework presented in this thesis will potentially be of use to a wide range of stakeholders such policy makers, local authorities, water companies, consultants and researchers. It could also be useful in informing the evolution of planning policies and technical guidance associated with water and green space planning.

Urban drainage systems are influenced by several future drivers that affect the performance as well as the costs of the systems. The uncertainties associated with future drivers and their impact creates difficulties in designing urban drainage systems sustainably. A review of the different future drivers for urban drainage systems illustrates that no sufficient future predictions for the long operational life spans of the systems are possible. This dissertation contends that to deal with future uncertainties, flexibility in urban drainage systems is necessary. At present, profound insights about defining, measuring, and generating flexible urban drainage systems do not exist. This research systematically approaches these issues. First, a clear definition of flexibility and an approach for the measurement and optimization of flexibility is operationalized. Based on the generic definitions of flexibility used in other disciplines, a definition tailored for urban drainage systems is generated. As such, flexibility in sustainable urban drainage systems is defined as `the ability of urban drainage systems to use their active capacity to act and respond to relevant alterations during operation in a performance-efficient, timely, and cost-effective way'. Next, a method for measuring flexibility is provided based on the developed definition of flexibility including the metrics, 'range of change', 'life-cycle performance' and 'effort of change'. These metrics are integrated into a framework for the measurement of flexibility based on a comparison of performance and effort in different alternative solution with respect to different future states. In addition the metrics are the core components for optimizing flexible design of urban drainage system. The measurement method is successfully applied in two case studies in Tuttle Hill, UK and Hamburg-Wilhelmsburg, Germany. Using the developed definition and method for the measurement of flexibility, this dissertation illustrates that a transfer of the general theoretical background of flexibility to the field of urban drainage is possible. It is currently unclear how the flexible design of urban drainage systems can be executed. Based on a review, this research identifies nine potential principles of flexible design, described by the indicators of modularity, platform design, flexible elements, cost efficiency, decentralized design, real time control, low degree of specialization, scalability, and a combination of these principles. A case study of Hamburg-Boberg is then presented to analyze which of these principles of flexible design can be verified. For each alternative solution in the sample, the indicators for the different potential principles of flexible design as well as the flexibility provided by the design are calculated. Testing is done to determine if there is a significant correlation between the potential principles of flexible design and the measured flexibility using a chi-square-test and F-test. Two principles are verified with a high degree of confidence, 'platform design' and `flexible elements'. The `platform design' principle provides high flexibility, in which urban drainage system elements with high change costs are designed robustly with huge tolerance margins, whereas elements with low change costs are designed with flexibility options. The 'flexible elements' principle aims to include as many component elements as possible, which provides high individual flexibility in the design of the urban drainage system. These design principles and associated static indicators enable a quick screening of huge number alternative solutions and provide guidance for the development and optimization of flexible urban drainage system. Within the framework for optimization of flexibility, the design principles can help identify the most promising alternative solutions for the design of urban drainage systems. The optimization framework includes the following steps: identification of the required flexibility, generation of alternative solutions for the design of urban drainage systems, screening of the most promising alternative solutions, detailed measurement of flexibility provided by the alternative solutions; and selection of optimal solution. Hence out of a sample of different design approaches, the solutions with the highest flexibility could be identified. The successful application of flexible design in three case studies illustrates that the concept provides a suitable strategy for dealing with the challenges associated with future uncertainties. For urban drainage systems, flexible design guarantees high levels of performance in uncertain future states while reducing the effort required to adapt the system to changing future conditions. This study contends that flexibility allows for profound decision making for urban drainage design despite future uncertainties.

Stormwater provides a direct link between urban infrastructure and the urbanised natural environment. In particular, highway drainage presents a high risk of pollution when compared to other urban land use areas (Ellis et al., 2012); introducing heavy metals, suspended solids and hydrocarbons to urban waterways. This research investigated runoff from the R300 highway, located in the greater Cape Town area. The City of Cape Town Management of Urban Stormwater Impacts Policy requires the treatment and attenuation of stormwater from developments within the city, and proposes Sustainable Drainage Systems (SuDS) as a means to achieve this (CSRM, 2009b). SuDS are structural and process controls that attenuate surface drainage, improve runoff water quality, provide amenity and deliver ecosystem services. This study characterized the R300 runoff through a sampling program and modelling exercise in order to provide an indication of the ability of SuDS to manage highway runoff in South Africa. Sediment and runoff samples were collected from the road surface and an undeveloped parcel of land adjacent to the highway. The sampling results showed that heavy metals, suspended solids and phosphorus are present in significantly greater concentrations in road runoff compared to rainwater from the same area. The concentration of aluminium, copper, lead, zinc and phosphorus exceed the Department of Water and Sanitation's water quality guidelines for aquatic ecosystems in excess of 1000%. The concentration of heavy metals, phosphorus and fats, oils and greases was significantly greater in road sediment compared to sediment from the surrounding area. Barring copper, all contaminant concentrations in the road surface sediment are less than the maximum concentration required to protect ecosystem health. The R300 rainfall-runoff response was modelled in PCSWMM to evaluate the performance of SuDS such as infiltration trenches, bioretention areas and swales for managing highway runoff in terms of quantity and quality. The modelling exercise showed SuDS to be a viable means to attain the City of Cape Town's stormwater objectives, provided that SuDS are implemented in treatment trains along the entire road length.

Dagens dagvattenhantering i urbana områden är inte hållbar vilket resulterar i översvämningar, förfallav naturen och hälsoproblem. Fortsatt urbanisering och klimatförändringar påverkar systemet negativtoch kräver en brådskande förändring. Ett alternativ till traditionell dagvattenhantering är naturligalösningar, NBS, definierat som inspiration och användandet av naturen för att hanterasamhällsproblem. Det kan ge resilienta och adaptiva lösningar som främjar biologisk mångfald,människors välbefinnande, ett lovande alternativ för att tackla de här problemen. NBS är dock förenatmed osäkerheter såsom kunskapsbrister kring prestanda, underhåll och möjliga negativakonsekvenser. Även om NBS kan anses vara en hållbar lösning är den inte frekvent implementerad iurbana områden. Den här uppsatsen använder fallstudien Årstafältet för att samla och analysera föroch nackdelar av NBS och traditionella dagvattenlösningar. Med hjälp av intervjuer med inblandadeaktörer, plandokument, regleringar och en litteraturstudie visar resultatet att NBS kan ge ett resilient,flexibelt och kostnads-effektivt system med multipla fördelar vilket kan uppfylla t.ex. vattendirektivet(WFD), hållbarhetsmålen (SDGs) och miljömålen. Det traditionella systemet är en oelastisk lösninginkapabel att förebygga miljöförändringarna och med frekvent breddning av smutsigt dag- ochavloppsvatten. Systemet är sett som oförmögen att uppfylla mål kring biologisk mångfald, miljömåloch reningskrav och därav en ohållbar lösning. Existerande infrastruktur och ett välarbetat arbetssättgör att det traditionella systemet dock fortfarande förlitas på. Problem som identifierades med NBSvar kunskapsbrister, en ny process för att hantera dagvatten som inkluderar en omfattande inblandningav aktörer, övergångsbarriärer, oklarheter gällande ansvarsfördelning, brist på deltagande frånallmänheten, avsaknad av tekniskt vägledning, bristen och behovet av att kontrollera och mätalösningar samt beroendet av entusiastiska aktörer.<br>The current stormwater management in urban areas is not sustainable, resulting in frequent floodingevents, degeneration of the environment and human health issues. Increased urbanization and climatechange negatively impact the outcome and calls for an urgent change. An alternative to traditionalstormwater management is nature-based solution, NBS, broadly defined as the usage or inspiration ofnature to address societal challenges. It can provide resilient, adaptive solutions which promotebiodiversity and human well-being, a solution to address these challenges. NBS is however unitedwith uncertainties such as knowledge gaps of performance, maintenance, efficiency and potentialtradeoffs. Although NBS can be considered a sustainable solution, it is not widely adopted andimplemented in urban areas. This thesis uses the case study of Årstafältet project to identify andanalyze opportunities and challenges of NBS and conventional drainage system. Based on interviewswith involved actors, plans, regulation and a conceptual framework, the result shows that NBS canprovide a resilient, flexible and cost-effective system with multiple benefits which addresses allaspects of sustainability. It is widely supported by laws and policies, addressing the EU WaterFramework Directive (WFD), the Sustainable Development Goals (SDGs) and the EnvironmentalObjectives for example. The conventional drainage system is an inflexible system unable to mitigateclimate change, with frequent overflows (CSOs) of dirty storm and sewage water. It is unable toachieve biodiversity goals, environmental objectives and water quality targets and thus recognized asan unsustainable solution. With an existing infrastructure and an established way of managing theconventional drainage system, it is however still relied on. Identified challenges of NBS areknowledge gaps, a new management process with extensive stakeholder involvement, transitionbarriers, unclear division of responsibilities, lack of public participation and technical guidance, lackof and the need to monitor solutions and the dependence on enthusiastic actors.

The research programme was relevant to urban planning and in particular to the design of stormwater management schemes that are more environmentally and socially acceptable. It examined social and perception issues relating to stormwater management techniques within residential areas, and in particular to the application of SUDS, mainly ponds, and river management schemes. The thesis arose from a project funded by the Environment Agency of England and Wales through SNIFFER under a programme titled “Social impacts o f stormwater management techniques including river management and SUDS”, SNIFFER Code: SUDS01. The public perception of construction is becoming a matter of increasing importance both in the UK and internationally since socio-economic parameters and public consultation both have to be taken into consideration in the planning and implementation of relevant projects. This research programme endeavoured to match the relevant legislative goals with society’s actual needs. The main aims of the research programme were to obtain an in-depth understanding and knowledge of the perceptions of popular stormwater management practices (SUDS and river management), and to evaluate these techniques from a social perspective. To satisfy these aims the following objectives were set: • To assess public awareness and perceptions of SUDS (particularly retention ponds) in the UK; • To assess professional perceptions of SUDS in the UK; • To assess perceptions of different stormwater management techniques, in three European cities; • To compare perceptions of different stormwater management techniques, SUDS and river management practices; • To link the research findings with trends in perceptions of nature and water. To meet the programme’s aims and to satisfy the objectives, the perceptions of SUDS in the UK (principally ponds) were investigated over a wide range of locations. In addition, the different river management approaches used in three heavily urbanised European cities, Glasgow, London, and Athens were investigated. The results of this research programme provide a means to understand perceptions of stormwater management and to appreciate what types of schemes will be more readily accepted by the public. The research has shown that members of the public hold strong views as to what they like or dislike about SUDS and water management installations in their local area, in spite of the fact that there were demonstrably low levels of public awareness of SUDS. The amenity, recreational value and aesthetics of new schemes seem to be of major importance for public acceptability, while function, efficiency, and maintenance are primarily important in areas facing flooding problems. Other key findings include the fact that there is a general preference for sustainable urban water management and for river restoration schemes compared with more conventional, ‘hard engineering’ approaches, such as culverting of rivers. This preference was expressed both by members of the public and by professionals involved in their planning and implementation. Another important result was that although unfamiliarity can produce negativity, education can influence attitudes positively even in sensitive issues such as safety, and can be used by authorities and planners as a means of enhancing the acceptability of new schemes. Consequently, the results of the surveys can be used as arguments towards the application of informative campaigns which should be taken into account prior to scheme implementation. This information can be utilised not only for stormwater management design, but also for other environmentally friendly constructions which the public may have a low level of awareness. Recommendations are made with respect to public and professional attitudes for improving the public acceptability of new and modified stormwater management systems. Recommendations and barriers to the uptake outlined in this thesis mainly refer to the appearance of schemes rather than technical issues. They are therefore of most use as guidance for improving aesthetics and increasing public acceptability. The outcomes of this research will be of use to policy makers, water companies, local authorities, environment agencies, planners, developers, consultants active in urban development, and researchers in applying wider-accepted practices for the assessment of public perception. Some findings from this research have been presented at several stakeholders’ meetings, at 4 conferences, and are published in the form of papers and reports, including the DTI SR 622 report titled “An Assessment of the Social Impacts of Sustainable Drainage Systems in the UK”, and the Environment Agency & SNIFFER report, SUDS01, 2005, titled “Social Impacts of stormwater management techniques including river management and SUDS”. This publication also constitutes Environment Agency R&D Technical report P2-258.

Increased flooding, urban diffuse pollution and habitat fragmentation are predicted as the climate changes and urbanisation increases; all will affect human and wildlife well-being negatively. Sustainable drainage systems (SuDS) have the potential to mitigate these effects and also provide additional amenity and biodiversity benefits. However, the current SuDS approach is site-specific and technically focused, hence, failing to generate anticipated amenity and biodiversity benefits. Therefore, a new SuDS approach is required. A critical evaluation of the SuDS approach, the Ecosystem Approach, ecosystem services and disservices enabled an innovative SuDS Communication and Planning Framework to be created. The framework highlights key amenity and biodiversity related ecosystem services and disservices produced by vegetated SuDS systems, coupled with drivers affecting the production of these services and disservices. This framework was validated by examining 49 representative sites within Greater Manchester using two ecosystem services and disservices variables assessment methods (vegetation structure cover-abundance and cultural ecosystem services and disservices appraisals). Resultant scores for five ecosystem services were calculated, where habitat for species and recreation ecosystem services were found to be synergistically linked to each other in a positive correlation. The result also enabled recommendations to be made that future vegetated SuDS development would benefit from involving local communities. Overall the research produced practical Ecosystem Approach methods for SuDS development decision making, and the SuDS Communication and Planning Framework provides an innovative, easy to use tool to implement Ecosystem Approach compliant solutions for key SuDS stakeholders (planners, developers, designers, researchers and policy makers). Finally, the SuDS Communication and Planning Framework can now be found in the second part of the UK National Ecosystem Approach, UK NEA follow-on, as part of a series of Ecosystem Approach toolkits incorporated into the decision making processes for managing the urban environment in a sustainable way.

El creixement de les ciutats arreu del món porta associat un increment en la demanda d’infraestructures de sanejament i drenatge. Combinat amb els efectes del canvi climàtic, la situació d’aquests sistemes en entorns urbans és crítica. Bona part dels sistemes de clavegueram existents requereixen una renovació urgent, d’altres han de ser construïts en zones en creixement, mentre que l’escolament superficial d’aigua pluvial esdevé una amenaça quant a inundacions degut a la impermeabilització del sòl. En aquest context, cal determinar quines són les millors pràctiques per reduir aquestes problemàtiques i al mateix temps adaptar les ciutats al canvi climàtic. En resposta a aquestes demandes, aquesta tesi estudia l’ecoeficiència dels sistemes de sanejament i drenatge urbà per determinar les millors alternatives en diferents contextos urbans. Així, es fa ús del marc de l’ecologia industrial, tot aplicant mètodes específics com l’anàlisi del cicle de vida (ACV), l’anàlisi dels costos del cicle de vida (ACCV) i l’ecoeficiència. Aquesta recerca interdisciplinària requereix mètodes addicionals, com ara estudis estadístics o anàlisis experimentals. El cicle de vida de les xarxes de clavegueram ha estat àmpliament analitzat i s’ha pogut observar que els materials de la canonada no són els únics determinants de l’impacte ambiental d’una solució constructiva per clavegueram. En alguns casos, la contribució de la rasa pot representar fins un 80% dels impactes ambientals de l’etapa constructiva, fet rellevant de cara a la presa de decisions. Mitjançant un estudi estructural paramètric s’han trobat les solucions constructives equivalents amb menor impacte ambiental. Així, reduir l’ús de formigó en les rases i reutilitzar els materials del sòl excavats pot significar una millora ambiental. Per altra banda, l’etapa d’operació mostra reptes en l’àmbit del planejament urbà. S’han comparat el municipi costaner de Calafell (Espanya, clima mediterrani) i Betanzos (Espanya, clima atlàntic). La ubicació de l’estació depuradora de Calafell a una cota més elevada que el municipi fa que el consum d’energia de bombeig (0.47 kWh/m3) sigui major que a Betanzos (0.11 kWh/m3), on l’aigua circula per gravetat. A més, s’han observat emissions gasoses al clavegueram a través de campanyes de mostreig. Principalment es van detectar majors emissions durant l’estiu associades a les elevades temperatures i en zones de turbulència del clavegueram. A més, mitjançant un estudi d’ecoeficiència, es van comparar els resultats ambientals i econòmics del cicle de vida del clavegueram i es va trobar que, independentment del clima i l’estructura urbana del municipi, l’etapa d’operació és la que genera més impactes ambientals (fins el 74% dels impactes), mentre que la instal·lació (és a dir, la rasa) contribueix als costos econòmics (70-75%). El debat de la centralització vers la descentralització de les infraestructures s’ha estudiat en un entorn insular (Menorca, Espanya) amb problemàtica turística. Ambientalment, sembla que un escenari centralitzat en què es connecta l’assentament a una depuradora de gran capacitat és beneficiós degut a les economies d’escala. Aquest escenari generaria un 12% menys impacte que descentralitzar parcialment amb fosses sèptiques o un 36% respecte a tractar el flux estacional en uns aiguamolls construïts. En general, els resultats depenen de la duració de l’època turística. En l’àmbit de la prevenció d’inundacions, s’aporta una nova visió, doncs es tracta d’un dels primers estudis que integra l’impacte ambiental i econòmic d’invertir en mesures preventives amb els danys evitats. Aquests són de gran interès per a la planificació urbana. En base a dos climes i sistemes diferents, s’han analitzat les rieres del Maresme (Catalunya) i un sistema verd implantat al Brasil. Des d’una perspectiva metodològica, els estudis d’inundacions aporten una discussió en l’àmbit de les metodologies d’ACV i en com abordar les conseqüències de les inundacions des d’un punt de vista integrador.<br>El crecimiento de las ciudades alrededor del mundo lleva asociado un incremento en la demanda de infraestructuras de saneamiento y drenaje asociadas al ciclo del agua. Combinado con los efectos del cambio climático, la situación de estos sistemas en entornos urbanos es crítica. Buena parte de las redes de alcantarillado existentes requieren una renovación urgente, otras han de ser construidas en zonas en crecimiento, mientras que la escorrentía superficial de agua pluvial es una amenaza en cuanto a inundaciones debido a la impermeabilización del suelo. En este contexto, se debe determinar a través de una nueva visión ambiental y económica cuáles son las mejoras prácticas para reducir estas problemáticas y al mismo tiempo adaptar a las ciudades al cambio climático. En respuesta a estas demandas, esta tesis estudia la ecoeficiencia de los sistemas de saneamiento y drenaje urbano para determinar las mejores alternativas en diferentes contextos urbanos. Así, se usó el marco de la ecología industrial, aplicando métodos específicos como el análisis del ciclo de vida (ACV), el análisis de costes del ciclo de vida (ACCV) y la ecoeficiencia. Esta investigación interdisciplinaria requiere métodos adicionales, como estudios estadísticos o análisis experimentales. El ciclo de vida de las redes de alcantarillado fue ampliamente analizado y se observó que los materiales de la tubería no son los únicos determinantes del impacto ambiental de una solución constructiva. En algunos casos, la contribución de la zanja representa hasta un 80% de los impactos ambientales de la etapa constructiva, hecho relevante para la toma de decisiones. Mediante un estudio estructural paramétrico encontraron las soluciones constructivas equivalentes con menor impacto ambiental. Así, reducir el uso de hormigón en las zanjas y reutilizar los materiales del suelo excavado puede significar una mejora ambiental. Por otro lado, la etapa de operación presenta retos en el ámbito del planeamiento urbano. Se compararon el municipio costero de Calafell (España, clima mediterráneo) y Betanzos (España, clima atlántico). La ubicación de la estación depuradora de Calafell a una cota más elevada que el municipio hace que el consumo de energía de bombeo (0.47 kWh/m3) sea mayor que en Betanzos (0.11 kWh/m3), donde el agua circula por gravedad. Además, se observaron emisiones gaseosas del alcantarillado a través de campañas de muestreo. Principalmente se detectaron mayores emisiones durante el verano asociadas a las elevadas temperaturas y en zonas de turbulencia del alcantarillado. Adicionalmente, mediante un estudio de ecoeficiencia se compararon los resultados ambientales y económicos del ciclo de vida del alcantarillado y se encontró que, independientemente del clima y la estructura urbana, la etapa de operación es la que genera más impactos ambientales (hasta el 74% de los impactos), mientras que la instalación (es decir, la zanja) contribuye a los costes económicos (70-75%). El debate de la centralización frente a la descentralización de las infraestructuras se estudió en un entorno insular (Menorca, España) con problemática turística. Ambientalmente, parece que un escenario centralizado en el que se conecta el asentamiento a una depuradora de gran capacidad es beneficioso debido a las economías de escala. Este escenario generaría un 12% menos impactos que descentralizar parcialmente con fosas sépticas o un 36% respecto a tratar el flujo estacional en un humedal construido. En general, los resultados dependen de la duración de la época turística. En el ámbito de la prevención de inundaciones, se aporta una nueva visión, pues se trata de los primeros estudios que integran el impacto ambiental y económico de invertir en medidas preventivas con los daños evitados. Estos estudios son de gran interés para la planificación urbana. En base a dos climas y sistemas diferentes, se analizaron las rieras del Maresme (Catalunya) y un sistema verde implantado en Brasil. Desde una perspectiva metodológica, los estudios de inundaciones aportan una discusión en el ámbito de las metodologías de ACV y en cómo abordar las consecuencias de las inundaciones desde un punto de vista integrador.<br>The growth of cities worldwide is associated with an increasing demand for sanitation and drainage infrastructure in the context of the water cycle. Combined with the effects of climate change, the situation of these systems in urban environments is critical. Part of the existing sewer networks require an imminent renovation, others must be constructed in developing areas, whereas stormwater runoff becomes a threat in terms of flooding because of the soil imperviousness. In this context, we must determine the best practices aimed at reducing these issues from an innovative environmental and economic viewpoint and at the same time adapt cities to climate change. In response to this demand, this dissertation assesses the eco-efficiency of urban sanitation and drainage systems to determine the best alternatives in different urban contexts. To this end, the industrial ecology framework is used by applying specific methods such as life cycle assessment (LCA), life cycle costing (LCC) and eco-efficiency. This interdisciplinary research requires additional methods, such as statistical studies or field experimental analyses. The life cycle of sewers was widely analyzed and it was observed that pipe materials are not the only factors that determine the environmental impacts of a sewer constructive solution. In some cases, the trench might contribute to 80% of the environmental impacts of the construction phase, which is a relevant issue to consider in decision-making. Through a structural parametric study, we found the equivalent constructive solutions that generate the lowest environmental impact. Reducing the use of concrete or reusing the excavated soil might entail environmental improvements. On the other hand, the operation stage is challenging in the context of urban planning. The coastal city of Calafell (Spain, Mediterranean climate) was compared with the city of Betanzos (Spain, Atlantic climate). The location of Calafell’s wastewater treatment plant at a higher elevation than the city resulted in Calafell consuming more pumping energy (0.47 kWh/m3) than Betanzos (0.11 kWh/m3), where wastewater flows gravitationally. Additionally, gas emissions were found in the sewer through sampling campaigns. The largest emissions were mainly detected during the summer due to high temperature, and in turbulent areas of the sewer. Furthermore, through an eco-efficiency assessment, the environmental and economic results of a sewer’s life cycle were compared. Regardless of climate and urban form, results show that the operation stage generates the largest environmental impacts (up to 74%), whereas the installation (i.e., the trench) mostly contributes to the economic costs (70-75%). The infrastructure centralization versus decentralization debate was studied in an insular context (Minorca, Spain) with a tourist-related issues. It seems that a centralized scenario that connects the settlement to an existing treatment plant with a large treatment capacity is environmentally beneficial due to economies of scale. This scenario entails a 12% impact reduction with respect to partial decentralization through septic tanks, or 36% reduction with respect to treating seasonal wastewater at a constructed wetland. In general, results depend on the duration of the seasonal period. In the field of flood prevention, this thesis provides a new vision, as these are the first studies that integrate the avoided impacts of damage prevention into the environmental and economic effects of investing in preventive measures. These analyses are of interest in the framework of urban planning. Based on two different climates and systems, ephemeral streams in the Maresme region (Catalonia, Spain) and a green system implemented in Brazil were assessed. From a methodological perspective, flooding analyses provide some ideas in the field of LCA methods and discuss how to deal with the consequences of flooding from an integrated viewpoint.

The dramatic global trend of population growth has led to a rapid urbanisation, resulting in unprecedented land cover change. The incarnation of accompanying developed has typified impermeable surfaces. These surfaces have disconnected the stormwater component of the natural hydrological cycle, disregarding it as a nuisance and designing it to be rapidly removed from urban areas. Utilising Sustainable Urban Drainage Systems (SUDS) offers opportunities in urban areas to recycle the water and challenge the perception that stormwater is a nuisance and of no value. The current context of drought experienced by Cape Town has highlighted the need for less reliance on surface water resources; implementing SUDS could be a way of reconnecting the hydrological urban water cycle. It could also help to repair the human disconnect from nature that is prevalent in urban areas. The research question explored the role of spatial planning in enabling the implementation of SUDS in the City Bowl, Cape Town. While conceptual and technical frameworks have been developed for SUDS in South Africa, at present there is no spatial guide as to how these interventions could be realised in a specific context and area. This research utilise s the tools of spatial planning to re-imagine the City Bowl in relation to water. The case study methods used, enabling a detailed understanding of the site. This was complemented by interviews with various planning professionals in order to understand the current role spatial planning plays in terms of implementing SUDS. The research suggest is that whilst SUDS has many constraints, the opportunities that they provide for improving water quality and quantity, and surrounding amenities, suggests that this is one which has to be embraced if the City Bowl is going to respond innovatively and sustainably to the drought. It also highlights the need to improve coordination across different spheres and departments of governance, and emphasises the need to value local community knowledge. A prevalent silo approach to complex problems is no longer acceptable. The implications of the research are that implementing SUDS in the City Bowl requires planners to embrace a water literacy approach to spatial plans, and in doing so, return the focus to water

This bachelor thesis aims to clarify the relationship between urban stormwater management and heritage sites. The topic is so far relatively unexplored, but may become highly relevant in the near future. Scientifically there is a lot of information about the impact from stormwater in heritage objects, also when repeated. The solution is sustainable urban drainage systems (SUDS) and insertion of green infrastructure in the actual area or the surrounding areas. However, science and local management are not the same. At a local level, more information is requested. It appears that, from the investigated examples in this thesis, the problem is to find available areas for the drainage systems. Also the protection and conservation of the heritage objects create restrictions considering changes in the actual area. However, it is not impossible to apply these solutions, as showed in the thesis concluding chapter. In general both experts and laymen are positive to the insertion, as long as SUDS are introduced in respect to the heritage values.<br>Denna kandidatuppsats har tittat på förhållandet dagvattenhantering och kulturmiljö. Det är ett relativt outforskat ämne, men kommer att bli relevant i en snar framtid. Forskningen visar på en kemisk nedbrytningsprocess av på kulturhistoriska objekt från dagvatten. Det är en problematik som ökar med klimatförändringarna. Lösningen som forskningen förespråkar är införande av en hållbar dagvattenhantering och grönska, vilket begränsas av kulturmiljöns riktlinjer och skydd. Det råder dessutom en platsbrist inom områden för kulturhistoriska objekt. Generellt sett finns det inget hinder från kulturmiljöns sida kring dagvattenhantering, men varje förändring ska noga vägas mot de kulturhistoriska värdena. Däremot är både tjänstemän och lekmän positivt inställda till miljömässiga fördelar så som en hållbar dagvattenhantering även i denna miljö.

With an ever-increasing population and global warming, fresh water resources are nearing depletion resulting in a global water crisis. As a consequence, cases of drought have been reported worldwide especially in sub-Saharan Africa. In addition to climate change, urbanisation adds strain to infrastructure as well as water supply and the management of water resources. As a result, most developing countries are faced with a water management challenge. There is thus a need for a paradigm shift towards an Integrated Water Management (IWM) approach. Worldwide, countries have responded to the Integrated Urban Water Management (IUWM) concept through the implementation of various management strategies; with Water Sensitive Urban Design (WSUD) emerging from Australia. Some closely allied management strategies in response to IUWM emerged in the USA as Low-Impact Development (LID), in the UK as Sustainable Drainage Systems (SuDS), and in New Zealand as Low-Impact Urban Design and Development (LIUDD). Namibia is situated along the south-west coast of Africa and is considered the driest country in sub-Saharan Africa. It is characterised by a semi-arid environment, with more than 80% covered by desert or semi-desert. The country is regularly afflicted by drought and has fluctuating and unreliable rainfall patterns, often accompanied by high evaporation rates. The City of Windhoek, as the capital city, the biggest municipality and also the largest densely populated town in Namibia, is faced with an ever-increasing shortage of water for its inhabitants. For close to 50 years, the water scarcity situation has led to direct waste water reclamation for potable re-use in Windhoek. Other measures implemented by the City of Windhoek (CoW) towards IUWM include Water Demand Management (WDM), Managed Aquifer Recharge (MAR) and Water Conservation (WC). In order for Windhoek to transform into a Water Sensitive City, the implementation of WSUD is imperative. Although the CoW has implemented measures towards IUWM, more options still need to be explored in order to contribute to IUWM processes and to ultimately become a Water Sensitive City. This research was aimed at conducting a comprehensive review of existing WSUD practices within the CoW and identifying gaps pertaining to WSUD implementation. The research confirmed, via a review of relevant literature, that the implementation of WSUD mainly flourishes when documented policies and regulations drive implementation. To review WSUD implementation in the CoW, this study followed a qualitative research approach by gathering data via online questionnaires using the SurveyMonkey platform. To validate the survey outcomes, structured interviews were conducted with selected survey participants to gain more insight into the outcomes. For the data collection, the study targeted a sample of managers and specialists from the three departments within the CoW that deal with urban infrastructure design and planning. A 72% response rate was achieved. The study revealed that there was a general understanding and knowledge of WSUD concepts among all the CoW stakeholders involved in water management, planning and design. This was mostly due to their academic knowledge and sometimes via exposure to existing WSUD practices within the city. Water Demand Management, Water Recycling, and Voluntary Green Roofs and Rainwater Harvesting were identified as existing WSUD options currently practised within the CoW. The study identified lack of capacity, lack of knowledge, lack of management support, a fragmented approach, the absence of policies and legislation, and no perceived financial benefits as barriers to WSUD implementation within the CoW. Based on the above findings, the study recommended that the City of Windhoek address existing barriers to WSUD implementation, increase awareness of WSUD within the city, secure government funding and apply for carbon credits to upscale the implementation of WSUD.

Sustainable urban Drainage Systems (SuDS) have become an important approach for protection of natural watercourses from non-point sources of pollution. In particular, filtration based SuDS build on the concept of simple, low-cost technology that has been utilized in water treatment for over a century. While it is widely studied and acknowledged that filtration of polluted water through granular material is extremely effective, the inherent geochemical and biogeochemical mechanisms are complex and difficult to ascertain. This is especially true for SuDS filter drains as they have been less well studied. Therefore, this thesis set out to quantify heavy metal removal in gravel filter drains and investigate (bio)geochemical mechanisms responsible for metal immobilization. Determining specific mechanisms responsible for pollutant removal within SuDS provides data that can be used to enhance SuDS design and performance. First, the impact of engineered iron-oxide coatings on heavy metal removal rates were investigated. It was determined that unamended microgabbro gravel immobilized similar quantities of heavy metals to the engineered iron oxide coated gravel. Consequently, engineered iron-oxide coatings were not recommended for future research or use in SuDS systems. Analysis of the surface of microgabbro gravel revealed the surface minerals are weathering to clays, enhancing the gravels affinity for heavy metals naturally. Comparison of microgabbro with other lithologies demonstrated microgabbro displayed enhanced removal by 3-80%. Comparison of microgabbro gravels with and without weathered surfaces demonstrated the weathered surface enhanced metal removal by 20%. From this, it is recommended weathered microgabbro gravel be used in filtration based SuDS where immobilization of incoming heavy metals typical in surface water runoff is important. Following this, the contribution to metal immobilization due to biofilm growth in a gravel filter was examined. Through heavy metal breakthrough curves obtained from experimental flow cells with and without biofilm growth, it was determined that biofilm enhances heavy metal removal between 8-29%. Breakthrough curves were modelled with an advection diffusion equation. The model demonstrated heavy metal removal mechanisms within the column could be described effectively by a permanent loss term. Further, the typical microbial community found within biofilms collected from an urban filter drain was determined to be composed of over 70% cyanobacteria. However, when inoculated into two different lithologies of gravel, the biofilm community composition changed and was influenced by gravel lithology. Dolomite gravel retained 47% cyanobacteria dominance while microgabbro demonstrated 54% proteobacteria dominance. Despite variations in biofilm composition, heavy metal removal capacity and mechanisms were broadly similar between different biofilm types. An additional approach to determine effects of biofilm growth on porosity and flow patterns through a horizontal gravel flow cell was assessed with non-invasive magnetic resonance imaging (MRI). While a copper (Cu) tracer could be imaged within the gravel flow cell, the transport pathways were too complicated to model as the Cu does not follow a plug flow. Processing of 3D high resolution images determined the porosity of the gravel filter to be between 32-34%, in line with literature values for coarse grained dolomite gravel. Further post-processing allowed for localized biofouling to be analyzed. Highest concentration of biofilm growth in columns resulted from longer growth periods and exposure to light. Moreover, biofilms tended to grow closer to the inlet which typically offers a higher nutrient dose and in pore space regions close to the light source (both of which would be representative of the surface of a filter drain). Thus, MRI analysis of biofouling has important implications for filter drain design and efficiency through assessment of pore space blockage. Finally, the possibility of enhancing heavy metal removal in sand (another filter material common in SuDS) with nano zero-valent iron (nZVI) particles was considered. Metal breakthrough curves for column experiments indicate that use of 10% nZVI enhanced sand improved metal immobilization between 12-30% and successfully removed > 98% Cu and Pb. It is therefore believed that nZVI enhanced sand is a promising avenue of future research for areas prone to high heavy metal loads.

Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2017-02-21T14:20:24Z No. of bitstreams: 1 TeseSPS.pdf: 7148087 bytes, checksum: 030a3087a773f12ba04ea57e6ff1eb13 (MD5)<br>Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-03-20T13:30:09Z (GMT) No. of bitstreams: 1 TeseSPS.pdf: 7148087 bytes, checksum: 030a3087a773f12ba04ea57e6ff1eb13 (MD5)<br>Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-03-20T13:30:17Z (GMT) No. of bitstreams: 1 TeseSPS.pdf: 7148087 bytes, checksum: 030a3087a773f12ba04ea57e6ff1eb13 (MD5)<br>Made available in DSpace on 2017-03-20T13:38:30Z (GMT). No. of bitstreams: 1 TeseSPS.pdf: 7148087 bytes, checksum: 030a3087a773f12ba04ea57e6ff1eb13 (MD5) Previous issue date: 2016-10-27<br>Não recebi financiamento<br>Many municipalities have problems with the drainage system and the excess rainwater in certain periods of the year. The management of cities should take into account the sustainability and for this, the indicators are important tools in helping to making the use and land use decision and thus avoid risk situations related to urban water. The sustainability principles guided the development of this research for this, were developed 13 sustainability principles specific to the management of stormwater based on general principles in the literature. After surveying the literature of sustainability indicators, they were found 102 indicators and of those, 65 that could be used in the management of rainwater, one of the indicators selection criteria was the correlation with the specific principles and other direct relationship with problem. Then we sought in the literature, the problems faced by the government and the people related to rainwater, were 47 major found this total, 19 were considered direct problems and the remaining effects caused by these problems. These 19 problems were divided into five dimensions of sustainability: environmental, social, economic, political, cultural and technological or management. For each problem have been assigned their respective indicators, a total of 54, leaving at least 2 indicators of the problem. Using multi-criteria method, priority indicators were selected, that is, those that would be most suitable for the monitoring of problems, however, in the absence of information available to these priority indicators can be used side indicators. These indicators served for the preparation of SAMSAP tool - Support System for Water Management Stormwater, which will serve for the development of scenarios for monitoring and decision making of managers and responsible for the management of rainwater.<br>Muitos municípios brasileiros apresentam problemas com o sistema de drenagem e com os excessos de águas pluviais em determinados períodos do ano. A gestão das cidades deve levar em conta a sustentabilidade e para isso, os indicadores são ferramentas importantes no auxílio à tomada de decisão do uso e ocupação do solo e dessa maneira evitarem situações de risco relacionados a águas urbanas. A finalidade foi produzir uma ferramenta capaz de orientar gestores do manejo de águas pluviais na tomada de decisão. Os princípios de sustentabilidade nortearam o desenvolvimento dessa pesquisa, para isso, foram elaborados 13 princípios de sustentabilidade específicos ao manejo de águas pluviais baseados em princípios genéricos presentes na literatura. Após o levantamento na literatura de indicadores de sustentabilidade, foram encontrados 102 indicadores e desses, 65 que poderiam ser utilizados no manejo de águas pluviais, um dos critérios de seleção dos indicadores foi a correlação com os princípios específicos e a outra a relação direta com o problema. Em seguida, buscou-se na literatura, os problemas enfrentados pelo poder público e pela população relacionados às águas pluviais, foram 47 os principais encontrados, desse total, 19 foram considerados problemas diretos e o restante, efeitos causados por esses problemas. Esses 19 problemas foram subdivididos em 5 dimensões de sustentabilidade: ambiental, social, econômica, política, cultural e tecnológica ou gestão. Para cada problema foram designados seus respectivos indicadores, num total de 54, cabendo no mínimo 2 indicadores por problema. Usando método multicritério, foram selecionados indicadores prioritários, isto é, aqueles que seriam mais adequados para o monitoramento dos problemas, entretanto, na ausência de informações disponíveis para o desses indicadores prioritários, poderá ser utilizado os indicadores secundários. Esses indicadores serviram para elaboração da ferramenta SAMSAP – Sistema de Apoio ao Manejo de Águas Pluviais, que servirá para a elaboração de cenários, para monitoramento e para tomada de decisão dos gestores e responsáveis pelo manejo de águas pluviais.

[EN] Under the well-known slogan 'think global, act local', cities in the 21st century face the enor-mous challenge of catalyzing, intensifying and accelerating sustainable urban transformations. Without losing a holistic view, the methodology presented in this thesis places the focus on 're-source management and climate mitigation and adaptation', in particular in urban stormwater management, proposing processes that can bring about the required change, shaped by the place-based approach of the regenerative sustainability paradigm. Building upon literature and practice that supports a flexible approach to stormwater manage-ment in urban environments that mimic natural processes and predevelopment hydrology (Sus-tainable Drainage Systems, SuDS) as one way to, amongst others, help to prevent and adapt to climate change, the thesis highlights the relevance of the connection to the place for adoption of best practices that conduct towards a regenerative system. Hence, it incorporates this con-nection to the place to the SuDS representation, naming it the SuDS 'landed rocket'. The proposed methodology includes a conceptual framework, specific method and tools, that allows for the understanding and the characterization of the current situation of a urban stormwater system in a process that guides future actions to move towards the desired regen-erative urban built environment concept, with a place-based holistic view. This methodology has been applied to Benaguasil, a Mediterranean city, where stormwater management is the local authority's responsibility and has been historically guided by main-stream conventional drainage practices. The thesis shows how, by taking a multi-dimensional and trans-disciplinary approach to solve environmental problems, future actions can be proper-ly addressed. Working with academia has been essential to develop wider evidence base. In this case, a sequence of research projects has advanced the innovative approach to stormwater management in Benaguasil, but it is contended that this methodology could be applied to any urban context. The thesis aims to enhance smart governance by providing information about the successful implementation and monitoring of SuDS showcase sites in Mediterranean Spain. These show-case sites are catalysts in the transition towards regenerative urban built environments in the region. In addition, it provides international examples that add further credence for improved urban ecological infrastructure by demonstrating what success can look like.<br>[ES] Bajo el conocido eslogan 'piensa global, actúa local', las ciudades del siglo XXI se enfrentan al gran reto de catalizar, intensificar y acelerar las transformaciones hacia un urbanismo sostenible. Desde una perspectiva holística, la metodología presentada en esta tesis se centra en 'la gestión de los recursos y la adaptación y mitigación al cambio climático', en particular en la gestión de las escorrentías urbanas, proponiendo los procesos que pueden ayudar al cambio requerido, bajo el enfoque del paradigma de la sostenibilidad regenerativa local. A partir de las referencias bibliográficas y experiencias que avalan a los Sistemas de Drenaje Sostenible (SuDS) como enfoque flexible a la gestión de las escorrentías urbanas, tratando de mimetizar los procesos hidrológicos previos al desarrollo urbano (que entre otros, contribuyen a la prevención y adaptación frente al cambio climático de las ciudades), la tesis subraya la relevancia de la conexión con el lugar para la selección de las mejores soluciones que lo conduzcan hacia un sistema regenerativo. Así, se incorpora esta conexión con el lugar a la representación de los SuDS, dándole el nombre de 'SuDS landed rocket'. La metodología propuesta incluye un marco conceptual, un método y herramientas específicas que permiten el entendimiento y caracterización de la situación actual de un sistema de drenaje urbano en un proceso que guíe acciones futuras para progresar hacia el concepto del medioambiente urbano regenerativo deseado, con una perspectiva holística local. La metodología se ha aplicado en Benaguasil, una ciudad mediterránea, donde la gestión del agua de lluvia es responsabilidad local y que ha estado influenciada históricamente por prácticas convencionales de drenaje. La tesis muestra cómo adoptando un enfoque multidimensional y multidisciplinar para resolver problemas medioambientales, las acciones futuras se pueden plantear correctamente. El trabajo con las instituciones académicas se ha demostrado esencial para desarrollar evidencias de base más amplias. En este caso, una serie de proyectos de investigación ha permitido el avance de Benaguasil hacia una gestión del agua de lluvia más innovadora. La experiencia demuestra que la metodología podría ser aplicada a cualquier otro contexto urbano. La tesis pretende mejorar la gobernanza inteligente proveyendo información respecto de la implementación y monitorización exitosas de SuDS en experiencias piloto en la España mediterránea. Estas demostraciones son catalizadoras de la transición hacia un medio ambiente urbano regenerativo en la región. Además, presenta ejemplos que se añaden al catálogo internacional de experiencias, mostrando el camino del éxito hacia un entorno urbano más saludable y habitable.<br>[CAT] Sota el conegut lema 'pensa global, actua local', les ciutats del segle XXI s'enfronten al gran repte de catalitzar, intensificar i accelerar les transformacions cap a un urbanisme sostenible. Des d'una perspectiva holística, la metodologia presentada en esta tesis es centra en 'la gestió dels recursos i la adaptació i mitigació al canvi climàtic', en particular en la gestió de les escorrenties urbanes, proposant processos que poden ajudar al canvi requés, des d'una òptica del paradigma de la sostenibilitat regenerativa local. A partir de les referències bibliogràfiques i experiències que avalen els Sistemes de Drenatge Sostenible (SuDS) com una aproximació flexible a la gestió de les escorrenties urbanes, tractant de mimetitzar els processos hidrològics previs al desenvolupament urbà (que entre altres, contribueixen a la prevenció i adaptació al canvi climàtic de les ciutats), la tesis subratlla la rellevància de la connexió al lloc per a la selecció de les millors solucions que el puguen conduir cap a un sistema regeneratiu. D'esta manera, s'incorpora esta connexió al lloc en la representació dels SuDS, donant-li el nom de 'SuDS landed rocket'. La metodologia proposta inclou un marc conceptual, un mètode i unes eines especifiques que permeten l'enteniment i caracterització de la situació actual d'un sistema de drenatge urbà en un procés que guie accions futures per a progressar cap al concepte de medi ambient urbà regeneratiu desitjat, amb una perspectiva holística local. La metodologia s'ha aplicat a Benaguasil, una ciutat mediterrània, on la gestió de l'aigua de pluja és responsabilitat local, i que ha estat influenciada històricament per pràctiques convencionals de drenatge. La tesis mostra com adoptant un punt de mira multidimensional i multidisciplinari per a resoldre problemes medi ambientals, les accions futures es poden plantejar correctament. El treball amb les institucions acadèmiques s'ha demostrat essencial per a crear evidències de base més amples. En este cas, una sèrie de projectes europeus d'investigació ha permès l'avanç de Benaguasil cap a una gestió de l'aigua de pluja més innovadora. L'experiència demostra que la metodologia podria ser aplicada a qualsevol altre context urbà. La tesis pretén millorar la governança intel¿ligent aportant informació respecte de la implementació i monitorització exitoses de SuDS en experiències pilot en la Espanya mediterrània. Estes demostracions son catalitzadores de la transició cap a un medi ambient urbà regeneratiu en la regió. A més a més, presenta exemples que s'afegeixen al catàleg internacional d'experiències, mostrant el camí del èxit cap a un entorn urbà més saludable i habitable.<br>Perales Momparler, CS. (2015). A regenerative urban stormwater management methodology. The role of SuDS construction and monitoring in the transition of a Mediterranean city [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59063<br>TESIS

The overarching goal of this research is to establish a successful forum for a transition from the existing paradigm of managing wastewater infrastructure to a more sustainable paradigm that achieves a more efficient utilisation of wastewater assets. A transitioning approach to support a more efficient utilisation of surface water and wastewater assets and infrastructure is proposed and developed. The determined transitioning approach possesses key stages namely developing the arena, developing the agenda, case study, and monitoring. The case study stage investigates a drainage utility identifying their improvement drivers, the removal of surface water through detailed drainage modelling and the financial examination of the costs incurred under the various scenarios conducted. Understanding the implications of removing/attenuating surface water from the network is improved through obtaining data by detailed drainage modelling. Infoworks software is used to investigate and assess the current and future operational scenarios of a wastewater system operating over one calendar year. Modelling scenarios were conducted removing surface water from selected areas focusing on the volumes requiring pumping and durations of pumping station(s) operation prior to treatment during storm conditions. The financial implication of removing surface water in combined sewer systems is examined in three main components. Firstly the costs of electricity incurred at the single sewage pumping station (SPS) investigated during the various scenarios modelled require to be addressed. Secondly the costs to retrofit sustainable urban drainage system (SUDS) solutions needs to be identified. Thirdly the implications of removing surface water for the drainage utility at the national level and the potential saving for householder’s committing to a surface water disconnection rebate scheme. When addressed at the macro level i.e., with over 2,100 pumping stations, some operating in sequence and contained within one drainage utility annually treating 315,360 megalitres the significance of the same multiple quantifiable and intangible benefits becomes amplified. The research aims, objectives and findings are presented to the identified and convened stakeholders. The transitioning approach developed encourages positive discourse between stakeholders. The level of success of the transitioning approach determined is then tested using a quantitative methodology through the completion of questionnaires. From the questionnaires completed the respondents unanimously agreed that surface water flows should be removed as well as reduced from the combined sewer system. The respondents agreed that the removal of surface water from a typical combined sewer system is justified by applying a transitioning approach focusing on the energy consumption required to pump increased volumes during storm events. This response is significant based upon the economic evidence and is contrary to the respondents previous position that finance was their most influencing factor. When provided with other potentially available benefits the respondents were even more supportive of the justification to remove surface water from the combined sewer system. The combined findings of the work presented in this thesis provide further justification that the transitioning approach applied to the removal of surface water from a typical combined sewer system, as determined in this research has been successful.

Over the past decades, the fast-changing global climate poses a significant challenge to many cities around the world to embrace resilience concepts, whereby a safe-to-fail planning approach replaces traditional fail-safe practices. The change in perspectives has seen an increase in climate-adapted infrastructural projects being integrated with the new urban planning agendas across the world. The investigation conducted was designed to understand the process of how resilience concepts travel between different cities, by investigating the actors who move policy knowledge, their roles in it, as well as the knowledge transfer process mechanism that is responsible for the movement of such policies. The investigation took advantage of a scoping study technique to answer the research questions, using mostly secondary data and an interview to verify the secondary sources. The findings and the discussion provided insights on who is involved in resilience policies and how these policies are transferred from one place to another. The investigation uncovered the influence policy mobilizers has on the movement of policy knowledge, as well as how the mobilization of policy knowledge can both be beneficial or detrimental, depending on the way it was moved or implemented.<br>Under de senaste decennierna utgör det snabba föränderliga globala klimatet en betydande utmaning för många städer runt om i världen med att anamma motståndskraftskoncept, där en planeringsstrategi med säkerhet att misslyckas ersätter traditionella felsäkra metoder. Förändringen i perspektiv har ökat klimatanpassade infrastrukturprojekten som integrerats med nya stadsplaneringsagendorna över hela världen. Studien genomfördes för att få en förståelse av hur motståndskraftskonceptet färdas mellan olika städer och detta genomfördes genom att undersöka de aktörer som förflyttar politisk kunskap och deras roller i den samt den kunskapsöverföringsmekanism som är ansvarig för rörelsen av sådan politik. Studien utnyttjade en scoping-studieteknik för att få svar på forskningsfrågorna, med mestadels sekundär data och en intervju för att verifiera sekundärkällorna. Resultaten och diskussionen gav insikter om vem som är inblandad i motståndskraft och hur policy överförs från en plats till en annan. Studien avslöjade även inflytande av politiskt mobilisering och kunskap som både kan vara fördelaktig eller skadlig beroende på hur den flyttades eller genomfördes.

Stormwater Management (SWM) or Best management practices (BMPs) treat the stormwater runoff that carries pollutants. Pollutants in the waters and in the stormwater, negatively impact the environment, the ecology, and natural resources. Stormwater Control Measures (SCM) are used in different projects to improve water quality and quantity. This thesis aims to understand the connection between SWMs, the economy, and environmental sustainability. This thesis evaluates the cost-effectiveness of SWMs in Mediterranean climates. The research aims to guide the next project managers to choose better SWMs based on cost-effectiveness, socio-economic, and environmental implications. Various studies suggest that the terms SWM, SWM, and SCM are used interchangeably. The research methodology uses a mix of qualitative and quantitative data analysis The research was conducted in Los Angeles at the request of UCLA. Therefore, it focused on water quality improvement projects in Los Angeles. The costs for the projects, areas, and whatSWMs are used will be acquired through data gathering and personal communication with experts. This thesis compares several projects which include different SWMs. It calculates the cost-effectiveness with two different methods, firstly, the cost per drainage area, and secondly, the cost per pollutant removed. Data is gathered from the city of LA and other secondary data sources to calculate the cost-effectiveness. The calculation results showed that the Glenoaksproject and the Machado lake project were the most cost-effective. Glenoaks utilizes infiltration wells and grass swales, and the Machado lake is a large wetland. Based upon these facts, generally, wetlands and grass swales can be recommended for Mediterranean climates. The expensive total costs of SWMs or their inability to remove pollutants can strongly affect the cost-effectiveness of some projects, and produce a negative impact on the economy. Quantitative assessment of study investigates cost-effectiveness of SWMs and for highlighting its economic impact. For qualitative assessment thematic analysis of 14 sample studies related to stormwater management (SWM) was carried out. Findings reveal that 78% of sample studies reflect the themes associated with the positive economic impact of SWMs. Additionally, the sample studies confirm a 76% positive impact of SWMs on the environment and ecology of the region. Further research with better data and more accurate calculations are needed. It would be beneficial if other factors such as recreation and unquantifiable factors such as the aesthetic improvements and community benefits were incorporated into or considered together with the cost-effectiveness for future projects.

L'essor que connaît aujourd'hui la gestion intégrée des eaux pluviales s'accompagne d'un recours croissant à des techniques favorisant l'infiltration de l'eau “à la source”, disséminées sur des bassins versants urbains. Néanmoins, de telles pratiques suscitent des interrogations sur la capacité du sol à jouer le rôle de “filtre” vis-à-vis des polluants présents dans le ruissellement. Ces travaux de thèse s'intéressent à la contamination du sol par les métaux et les hydrocarbures aromatiques polycycliques (HAP) dans ces dispositifs, avec trois objectifs : (i) évaluer les niveaux et l'étendue spatiale de la contamination, (ii) mieux comprendre les mécanismes qui gouvernent le devenir de ces contaminants dans le sol des ouvrages, et (iii) proposer des recommandations sur la conception et la maintenance de ces installations, afin de leur assurer un fonctionnement épuratoire durable.La première partie du travail consiste en une série d'investigations expérimentales sur dix sites d'étude aux caractéristiques contrastées, en service depuis plus de dix ans. Cette phase donne lieu à des cartographies de la contamination superficielle en éléments traces métalliques, puis à des profils verticaux de métaux et HAP, accompagnés de différentes variables explicatives. La distribution spatiale des métaux en surface, qui est toujours structurée autour de la zone d'arrivée de l'eau, porte la signature du fonctionnement hydraulique réel des dispositifs, et révèle le caractère non-uniforme de l'infiltration lors des événements pluvieux courants, qui représentent la plus grande partie du flux polluant à l'échelle annuelle. Dans la zone la plus contaminée des ouvrages, métaux et HAP présentent un enrichissement significatif sur 10 à 40 centimètres de profondeur. La rétention des contaminants résulte de la combinaison de processus physico-chimiques (adsorption) et mécaniques (sédimentation et filtration) ; leur importance relative peut être quantifiée grâce au déficit de zirconium dans le sédiment urbain par rapport au bruit de fond géochimique local. La variabilité inter-sites des niveaux de contamination s'explique à la fois par les capacités de rétention du sol et par les flux de polluants issus du bassin versant d'apport. Bien que les teneurs de surface excèdent, sur certains sites, les seuils internationaux de remédiation du sol pour des espaces “multifonctionnels”, la zone concernée représente — latéralement et verticalement — une région assez limitée dans les ouvrages.La seconde partie de la thèse consiste en une approche de modélisation, dont la finalité est de décrire l'évolution à long terme de la contamination du sol, et d'évaluer l'incidence de différentes pratiques de conception ou de gestion. Une analyse de sensibilité est d'abord mise en œuvre afin d'identifier les “éléments-clés” dans la description du système, et d'orienter le choix du modèle. Les résultats montrent qu'une mauvaise estimation de la dispersivité ou de l'isotherme d'adsorption du sol est susceptible de biaiser significativement la prévision des profils de contamination. Dans la suite du travail, on propose une méthode visant à décrire l'infiltration non-uniforme et la filtration des polluants particulaires. Le modèle ainsi construit est validé via une comparaison entre mesures et simulations sur l'un des sites d'étude faisant l'objet d'une nouvelle caractérisation approfondie. Enfin, une analyse de scénarios illustre les bénéfices d'un amendement de l'horizon superficiel par un matériau adsorbant, ainsi que d'une répartition homogène des flux d'eau en surface, en matière de durée de vie des installations et de fréquence d'intervention<br>Sustainable Urban Drainage Systems (SUDS) are increasingly used for stormwater management. However, the generalization of runoff infiltration in urban watersheds raises some concerns regarding the soil's ability to retain ubiquitous micropollutants. The present work addresses soil contamination by trace metals and polycyclic aromatic hydrocarbons (PAHs) in such infiltration devices, with the aims of: (i) appraising the levels and spatial extent of soil contamination, (ii) better understanding the mechanisms which govern the fate of contaminants in these systems, and (iii) identifying design and maintenance guidelines which may enhance long-term pollutant control through SUDS.The first part of the study consists in a series of experimental investigations in ten contrasting study sites, which have been in operation for more than ten years. The two-stage methodology successively leads to cartographies of metal contamination in the surface soil, and vertical profiles of metal and PAH concentrations, along with different explanatory variables. The spatial distribution of trace metals in the upper horizon displays a systematic structure with respect to the inflow area, and bears the time-integrated signature of the infiltration fluxes and flow pathways at the surface. In the most contaminated zone of the facilities, a significant enrichment of metals and PAHs is detectable until 10 to 40 cm depth. Contaminant retention results from the combination of different physicochemical and mechanical processes (resp. sorption and sedimentation/filtration), the contribution of which can be assessed via the zirconium deficit in urban sediment in comparison to the soil's geochemical background. The inter-site variability of contamination levels is attributable to (i) differences in the soil's retention capacities, and (ii) differences in pollutant loads from the watershed. Although surface contents may exceed intervention thresholds for “multi-functional” spaces in several study sites, the area which would require soil remediation is laterally and vertically limited.These experimental assessments are complemented by a modelling approach, to describe the long-term evolution of soil contamination, and to evaluate the effect of various SUDS designs and maintenance operations. A sensitivity analysis is first carried out so as to identify the “key elements” in the system description: the results show that a wrong estimation of the soil's dispersivity or sorption isotherm is likely to induce significant biases in the predicted contamination profiles. A method is then proposed to describe non-uniform water infiltration fluxes, and the filtration of particle-bound contaminants. The model is validated via a comparison between measured and predicted metal profiles in one of the study sites, where a comprehensive soil characterization is undertaken. Finally, a “scenario analysis” illustrates the benefits of (i) using soil enrichment products with enhanced sorption capacities, and (ii) facilitating water spreading at the surface, in terms of “lifespan” of the devices and maintenance requirements

Ce travail de thèse a évalué les niveaux et les voies d'introduction de la contamination en micropolluants des eaux pluviales d'un petit bassin versant urbain, et mis en évidence les impacts de l'utilisation de techniques alternatives (TA) sur les flux d'eau et de contaminants. Quatre bassins versants à Noisy-le-Grand, homogènes par leur taille et leur occupation du sol (1 à 2 ha, résidentiel dense), et présentant une diversité de gestion des eaux pluviales (séparatif classique et différentes combinaisons de TA) ont été étudiés. La présence d'un certain nombre de substances prioritaires de la directive cadre européenne sur l'eau (HAP, alkylphénols, phtalates, diuron, isoproturon, atrazine, plomb) a été mise en évidence dans les eaux pluviales d'un bassin versant amont, à des niveaux de contamination globalement plus faibles qu'à l'aval des réseaux séparatifs. Cette contamination est tout de même significative pour certains paramètres qui ont été mesurés au dessus des normes de qualité. Pour le zinc, la contamination à l'amont est même plus élevée qu'à l'aval du fait de l'émission par des matériaux de couverture.Ce travail a montré que les TA diminuent les volumes d'eau rejetés vers l'aval d'environ 50% et réduisent les masses de contaminants émises de 20 à 80% (MES, DCO, PCB, HAP, alkylphénols, métaux traces). Cette réduction de masse est essentiellement liée à la diminution de volume, l'effet épuratoire sur les concentrations n'étant pas systématiquement mis en évidence. L'amplitude de ces effets varie suivant l'importance de la pluie, mais surtout en fonction du type d'ouvrage mis en place.La gestion à l'amont des eaux pluviales est donc à favoriser car elle évite la sur-contamination liée aux processus en réseau (mauvais branchements, érosion...). Elle permet de séparer les eaux peu chargées (infiltration ou rejet au milieu) des effluents contaminés qui pourront être traités localement ou à l'aval. Dans un objectif de réduction des flux polluants la conception des TA devra prendre en compte les pluies courantes et non pas seulement les événements exceptionnels

The drainage behaviour of sports pitches is not well understood nor has performance been measured in the past. Within planning authorities there is a perceived contribution of pitch water discharge to local flood risk; whereby all the rainfall surface runoff is rapidly channelled through the drainage system to the pitch outfall. However, empirical evidence from industry suggested that this may not be a realistic assumption from observations of low drainage volumes yielded from pitch drainage systems. Furthermore, discharge constraints imposed have in many cases resulted in grossly over-designed off-line drainage attenuation systems for new sports developments through lack of understanding. In contrast, sports pitches indeed have the potential to enhance the attenuation performance of the subsoils and provide localised effective management of surface water runoff, and a significant storage volume if designed appropriately The findings in this thesis confirm that pitch bases demonstrate the key functions that are in fact reflected in the design requirements of Sustainable Urban Drainage Systems (SuDS). This PhD research project was conducted to investigate and document the performance of common pitch construction and drainage systems to better characterise the key drainage mechanisms that occur and control the flow of surface rain water through the pitch to the discharge outfall. The project developed a triangulated approach to the investigations, comprising: field measurements of climate and discharge behaviour at a range of artificial and natural turf pitches in England; laboratory physical model testing of pitch component hydraulics; and predictive mathematical modelling of how a pitch system may be expected to perform hydraulically based on key material and system drainage principles. The field monitoring systems were developed as part of the research, as was bespoke laboratory physical simulation of a pitch construction. It was found that very variable yields (% out versus % in) of water were detected from the monitored field sites. The values varied across a range of < 1 to 88%, with the natural turf providing higher yields in general. The antecedent weather patterns did not show a clear relationship with yield as might have been expected. However, it was not always possible to retrieve detailed information on the subsoil conditions or hydraulic capability reducing the conclusiveness of the discharge flow measurements. The scaled laboratory testing of pitch materials established the importance and magnitude of barriers to percolation of surface water through the layers of the pitch constructions, in particular artificial pitch profiles. It was found that a significant proportion of the total rainfall head was required to instigate percolation of surface water through the carpet and into the pitch i.e. breakthrough head. In addition, several constituent pitch materials exhibited water retention characteristics that reduced that rate of free percolation of surface water through the pitch profile. The net impact is to reduce the net available head of water to further drive flow through the layers to the pipe network drainage system. A conceptual hydraulic model, developed from the literature, was further developed into a simple numerical model. The model was informed by parameters determined from the laboratory measurements and key groundwater drainage flow theory to attempt to replicate a pitch drainage system. It was envisaged that the models would be validated by the field data, although this proved challenging as a result of the field data variability and the multivariate nature of the influences on flows measured. A key finding of the modelling was further establishing the likely head of water generated at the interfaces between the bottom of the granular sub-base and the pipe collection drainage system beneath. This resulted in limited pipe infiltration and low total flows to the outfall, further corroborating the project field results and the anecdotal observations from practitioners. The combined unique data sets provide a refined model for sports pitch drainage to both reinforce understanding and inform practical design and operation.

El fenómeno El Niño provoca intensas precipitaciones pluviales que se acumulan y discurren por la superficie, transportando importantes caudales de agua que se incrementan con el desplazamiento debido a la carencia de un pavimento permeable como sucede en la ciudad de Tumbes. Esta deficiencia produce daños en los sistemas de abastecimiento de agua, alcantarillado y aguas pluviales que, debido a la cantidad de basura y lodo que transportan los azolvamientos severos, afectan a las infraestructuras hidráulicas, medio ambiente y calidad de vida de la población. Una propuesta de solución es utilizar un sistema de drenaje urbano sostenible que permita complementar el sistema único de saneamiento diseñado para las aguas servidas, residuales y pluviales, existente en la gran mayoría de ciudades. Esta solución consiste en el diseño de un pavimento permeable porque permite alcanzar un volumen de captación de agua de 81-730 l/min/m2 debido al contenido de vacíos de 13 a 25%. Esta característica física es importante para garantizar la infiltración de grandes volúmenes de agua mediante sus poros para luego transmitir a estratos subyacentes; reducir el flujo del calor al conductor; y mitigar la isla de calor urbano en las ciudades. La presente investigación tiene como objetivo evaluar el desempeño del concreto permeable mediante 5 diseños de mezcla para estudiar la resistencia a la compresión, a la flexión y permeabilidad; la comparación de la escorrentía superficial pluvial de un pavimento de concreto permeable con un pavimento de concreto convencional mediante el software SWMM 5.1; y la comparación respecto al costo.<br>The El Niño phenomenon causes intense rainfall that accumulates and runs over the surface, transporting significant volumes of water that increase with displacement due to the lack of a permeable pavement, as happens in the city of Tumbes. This deficiency causes damage to the water supply, sewerage, and rainwater systems that, due to the amount of garbage and mud transported by severe silts, affect the hydraulic infrastructures, environment, and quality of life of the population. A proposed solution is to use a sustainable urban drainage system that allows complementing the unique sanitation system designed for sewage, waste, and storm water, existing in most cities. This solution consists of the design of a permeable pavement because it allows reaching a water collection volume of 81-730 l/min/m2 due to the void content of 13 to 25%. This physical characteristic is important to guarantee the infiltration of large volumes of water through its pores and then transmit to underlying strata; reduce heat flow to the conductor; and mitigate the urban heat island in cities. The objective of this research is to evaluate the performance of permeable concrete through 5 mix designs to study the resistance to compression, bending and permeability; the comparison of the surface rain runoff of a permeable concrete pavement with a conventional concrete pavement using SWMM 5.1 software; and the cost comparison.<br>Tesis

Urbanisation, a process associated with industrialisation and development has been characterised by unsustainable impacts such as increased impervious surfaces, increased air pollution, increased use of natural resources, increased volume of surface run-off, decreased quality of surface run-off, and depletion of biodiversity and habitats. The effects of these impacts on the environment include climate change, flooding, erosion, pollution of water bodies, and destruction of aquatic life and biodiversity. Studies have shown that sustainable designs such as Sustainable Drainage Systems (SuDS) would help mitigate some of these effects sustainably. SuDS are natural drainage systems that simulate the natural drainage of a site/catchment and work in harmony to achieve increase in ground infiltration and treatment of runoff; and reduction in flow rates and volume of surface runoff, thereby improving storm water quality, reducing erosion, recharging groundwater, improving biodiversity and ultimately improving sustainability. However, sustainability of SuDS devices are questionable because their component parts involve the use of natural resources i.e. topsoil and gravel. The overall aim of this research was to evaluate the efficacy of the application of recycled/waste materials in performing at least as well as topsoil and gravel in vegetative SuDS, thereby improving water quality and overall sustainability. The materials applied were compost and recycled aggregates. In assessing their efficacy in vegetative SuDS, the risk these materials could pose to water quality was not overlooked but was considered in establishing an ideal model for the treatment of pollutants in vegetative SuDS. Results of this research showed that overall compost and recycled aggregates were able to perform at least as well as gravel and topsoil in vegetative SuDS in terms of characterisation, biofilm and vegetative development, and remediation of runoff pollutants thereby improving the sustainability of vegetative SuDS. Compared to gravel and topsoil, characterisation of compost and recycled aggregates was shown to be less expensive, less time consuming (except for recycled aggregates) and more sustainable, in terms of conserving natural resources. It was deduced that compost would be able to biodegrade organic pollutants in vegetative SuDS in varying conditions, compared to topsoil, thereby improving water quality. Vegetative growth in profiles containing compost were more prolific than those with topsoil alone, indicating that vegetative SuDS containing compost would attenuate stormwater and remediate pollutants by phytoremediation, better than topsoil. Results showed that compost and recycled aggregates performed as well as gravel and topsoil in remediating pollutants, with >98% of pollutants being retained mostly within the growth media, confirming that most pollutants are treated within the growth media of vegetative SuDS devices. This research was able to establish that SuDS components can be as unsustainable as components of conventional drainage systems in terms of their social, economic and environmental impacts; and that recycled materials could perform just as well as conventional materials, whilst improving their sustainability. This research further established that compost and recycled aggregates can be used in vegetative SuDS, such as swales, as literature has shown that the use of compost and recycled aggregates in vegetative SuDS has been limited to compost blankets and socks and substrates for green roofs. Suggestions for other waste materials that can be used instead topsoil and gravel in vegetative SuDS were also made. Results from this research were applied in the development of a swale model for the treatment of pollutants in vegetative SuDS.

One of the main challenges in promoting rainwater management into practise is the fact that it was not recognized as an interdisciplinary issue. We should seek ways how to open the problem to other professions, specially for architects and urban planners, who are the key element of its farther development. This work analyzes the reasons of this unsatisfactory state of rainwater management in the Czech Republic and it defines the possible ways how to remedy this state and outlines scenarios of its further development. The default document of the work is czech technical standard "TNV 75 9010 Hospodaření se srážkovými vodami". The new methodological guide, which is part of this work, is based on it. The work extends the range of measures which are mentioned in the standard. It brings new ways for assessing the benefits of the various measures to streamline the application of rainwater management measures in urban space.

The El Niño phenomenon is caused by the change in atmospheric pressures, which produce the accumulation of hot surface waters on the eastern flank of the Pacific Ocean; causing intense rainfall that runs over the surface affecting the urban drainage of the city due to the lack of a permeable pavement; porous concrete allows infiltration of surface water runoff through its pores. The present investigation evaluates porous concrete in the range of w/c relationships of 0.30 and 0.32; the results indicate that the compressive strength, flexural strength and permeability coefficient increase; and that the surface runoff, cost, water footprint and carbon footprint are lower than conventional concrete.

Urban drainage in Saudi Arabia is an increasingly challenging issue due to factors such as climate change and rapid urban expansion. The existing infrastructure, based on traditional drainage systems, is not always able to cope with the increased precipitation, sometimes leading to rainwater runoff and floods causing disturbances and damage to property. Therefore, there is a need to find new ways of managing drainage, such as Sustainable Urban Drainage Systems (SUDS). This thesis places knowledge as a central issue in the adoption of Sustainable Urban Drainage approaches, as revealed through qualitative research with representative officials and professionals from key government departments and organisations in Riyadh. Twenty-six semi-structured interviews were conducted during fieldwork in 2013 and 2014, which explored the challenges in adopting sustainable drainage approaches, and through a Grounded Theory analysis, the key role of knowledge was revealed. This research identifies barriers to change in favour of the adoption of sustainable drainage approaches, such as the marginal status of sustainable development in drainage decisions; lack of technical standards for other unconventional drainage solutions; and lack of consideration by decision makers in other disciplines such as contributions from environmental and geographical studies. Due to the form of centralisation revealed, decision-making processes are complex and time-consuming; resulting in the discouragement of the adoption of new knowledge and approaches. Stakeholders with knowledge of sustainable approaches are often excluded from the hierarchical system of urban planning and drainage management. In addition, the multiplicity of actors involved in drainage implementation and the different technical standards cause problems around coordination and cooperation. Three types of knowledge of sustainable approaches and unconventional experiences were revealed across government departments and institutions. From those participants who have procedural and explicit knowledge, a range of opportunities (e.g. significant increase in government support) and obstacles (e.g. the deficit in specialists on sustainable approaches) were revealed regarding adopting new approaches. The thesis presents recommendations for overcoming some of the challenges revealed in the context of Saudi Arabia; such as enhancing the decision-making process through applying decentralisation, and promoting awareness of sustainability and sustainable development through establishing educational and outreach programmes. This would enhance knowledge and facilitate the adoption of sustainable drainage approaches to promote sustainable development.

Orientador : Ph.D. Daniel Costa dos Santos<br>Coorientador : Ph.D. Berry Gersonius<br>Tese (doutorado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia de Recursos Hídricos e Ambiental. Defesa: Curitiba, 28/03/2016<br>Inclui referências : p. 121-130<br>Resumo: O desenvolvimento das áreas urbanas e a consequente impermeabilização dos solos são responsáveis por grandes alterações no ciclo hidrológico natural. Enquanto ocorre a diminuição das taxas de evapotranspiração e infiltração, há um aumento no volume de escoamento superficial além da diminuição do tempo de concentração das bacias hidrográficas. No Brasil, grande parte das áreas urbanas se desenvolveram sem o devido planejamento o que, aliado a cultura de projeto, contribuiu para a implementação de sistemas tradicionais de drenagem, os quais visam o lançamento da água de escoamento superficial o mais rápido possível em um corpo hídrico receptor. Tal abordagem vai de encontro às metas de sustentabilidade e constam de soluções inadequadas para o controle de poluição e das inundações. No entanto, o uso de soluções alternativas está longe de se tornar realidade no Brasil. Apesar disso, há um crescente desenvolvimento de ferramentas de gestão que visam auxiliar o processo de tomada de decisão e a implementação de abordagens mais sustentáveis para as áreas urbanas. Por outro lado, não há consenso quanto a melhor abordagem a se utilizar. Neste contexto, o presente trabalho objetivou adaptar o Urban Water Use (UWU) Model, no intuito de tornar viável a avaliação de medidas de drenagem urbana sustentável (SuDS) e auxiliar o processo de tomada de decisão, além de contribuir para o debate e modernização da infraestrutura de drenagem urbana no Brasil. A metodologia foi dividida em duas etapas principais: o desenvolvimento do módulo de drenagem (Etapa 1), e a aplicação do modelo (Etapa 2). Foram implementados sete indicadores e cinco medidas de SuDS. Não obstante, o método de formulação dos cenários foi adaptado. A seguir, o modelo foi aplicado em uma pequena bacia urbana (208;44 hectares) na Região Metropolitana de Curitiba (RMC), no norte da bacia do Rio Belém. Quatro cenários foram formulados para um horizonte de projeto de 30 anos e cinco diferentes grupos de medidas (GMm) foram propostos. As seguintes medidas foram utilizadas: trincheiras de infiltração, pavimentos permeáveis, utilização de águas pluviais nas edificações, bacias de detenção e bioretenções. As visions foram estabelecidas com base nas estimativas iniciais e seus atuais valores. Os resultados demonstraram a possibilidade de avaliação dos grupos de medidas de drenagem urbana sustentável considerando o atendimento ou não aos critérios estabelecidos por meio de indicadores e metas refletidas nas visions. Além disso, foi possível se estabelecer interfaces entre o sistema de drenagem urbana e o de abastecimento de água por meio do uso de água da chuva nas edificações e as tabelas de parametrização do consumo residencial. Excetuando-se os grupos de controle (GM0 and GM5), os resultados mostraram que a combinação de bacias de detenção, bioretenções e coleta de água de chuva (GM2) forma o melhor grupo de medidas para a área de estudo considerando os critérios avaliados. Portanto, o UWU Model se mostrou útil no processo de tomada de decisão para o planejamento de medidas de drenagem urbana. Nesse sentido, a principal contribuição do presente trabalho foi a adaptação do modelo, fornecendo um ambiente integrado para avaliação das medidas. Trabalhos futuros devem ser desenvolvidos no sentido de testar o modelo em outras áreas buscando a adição de novos indicadores e medidas. Palavras-chave: UWU Model; sistemas de drenagem sustentáveis; abordagem integrada, planejamento estratégico; tomada de decisão.<br>Abstract: It is well known that developed urban areas are characterized by alteration of the natural hydrologic cycle. Whereas evapotranspiration and infiltration decrease, there is an increase in the runoff volume. In Brazil, many urban areas have developed without any kind of planning. It has led to the implementation of drainage systems which primarily focus on collecting, transporting and disposing as quickly as possible the runoff into a receiving water body. These systems, called traditional systems, were not designed in agreement with the sustainability goals, and appears to be an inadequate solution to flood control since it has contributed to flooding downstream and to water body pollution. However, alternative solutions are still incipient in Brazil due to many issues that remain uncertain regarding the use of such technologies. Currently, some tools are being developed in order to assist the decision-making process and help planners to implement more sustainable approaches in cities, but the debate remains as the best approach. In this context, present work aimed at improving the Urban Water Use (UWU) Model and implement it as a decision-making support tool for sustainable urban drainage systems and contribute to the discussion and modernization of urban drainage infrastructure in Brazil. The methodology was divided into two main phases which were the drainage module development (Phase 1) and a case study application (Phase 2) in order to test the whole model. Seven indicators and five sustainable drainage measures were implemented. Notwithstanding, the scenarios formulation approach was adapted. Hereafter, the model was applied in a small study area (208:44 hectares) in the Curitiba Metropolitan Region (CMR), located within the Belém river basin. Four future scenarios were formulated considering a design period of 30 years and five different groups of measures (GMm) were tested. The groups of measures combined the following structural measures: infiltration trenches, permeable pavements, rainwater harvesting, stormwater detention basins, and bioretention. The visions were established based on current and initial estimates and six simulations were performed in order to test the model outcomes. The results demonstrate the possibility of evaluating groups of drainage measures as to meet the indicators' visions in the formulated scenarios by using the UWU Model structure. Notwithstanding, the simulations showed that drainage measures can be evaluated in an integrated context linking the rainwater harvesting devices and the water usage per appliance in the buildings. Disregarding the control groups (GM0 and GM5), the results showed that a combination of detention basins, bioretentions and rainwater harvesting devices (GM2) was the best group of measures to the study area considering the selected indicators. Therefore, the UWU Model could be useful in the decisionmaking process when planning the drainage measures for urban areas. In this sense, this work main contribution was to adapt the original model and provide an integrated environment for drainage measures evaluation. Further work could implement other indicators and measures and integrate the drainage measures with sewage system indicators. Key-words: UWU Model; sustainable drainage system; integrated approach, strategic planning; decision-making.

Urban SIS is a project that develops, demonstrates and puts into production a method to downscale climate and impact indicators to urban scale, realizing a set of Essential Climate Variables over three area of Europe, including Bologna; in particular the precipitation was estimated for 5 non-consecutives years at a spatial resolution of 1x1 km2 and a temporal resolution of 15 min. The database of the area of Bologna contains an amount of data in the order of 10 millions that was managed in this study with RStudio. An analysis of the high resolution precipitation data over the most critical flood prone area of Bologna was performed, selecting a set of critical rainfall events. In the selection were considered the intensities, the cumulated depth and an index of spatial rainfall variability, taken from a firstly in-depth research in the literature regarding the use and the application of high resolution precipitation data in urban drainage modelling. Thanks to HERA, that gently provided the model of the entire urban drainage network of Bologna and the license for the utilization of InfoWorks software, the high resolution precipitation data were implemented into the drainage system. A series of indicators were calculated, in order to quantify the critical surcharge and flooded states of the network. Using the Intensity-Duration-Frequency curves of the area of Bologna, two types of synthetic events were elaborated: one constant over the area and another one with a pyramidal structure, representing the effects of a pour down rainfall event. The comparison between the synthetic events and the selected ones from Urban SIS assesses the direct correlation between the evaluation of the intensity at 1 hour and the indicators of the critical states in the network; the index of spatial rainfall variability has proved to be irrelevant in most of the cases. This study has to be considered valid for the urban drainage system of the area of Bologna.

Thesis (Doctoral)--İzmir Institute Of Technology, İzmir, 2005.<br>Keywords:Infrastructure, city form, sustainable development, sewerage systems, geographical information systems. Includes bibliographical references (leaves. 164-174).

Cape Town is experiencing its worst drought in recorded history. Notwithstanding that the Western Cape has always been a water scarce region, it is this current drought that has brought home the area’s inherent vulnerability and highlighted the governance issues. The world wherein South Africa’s water governance was created is very different to the world we find ourselves in today. It is a world of uncertainty and unpredictability not contemplated in water governance comprised of legislation, policy, guidelines and practice. The current water governance constructs a conventional approach based upon predictability and certainty and is no longer appropriate to meet today’s new challenges. Consistent with this conventional approach, Cape Town’s municipal water supply is almost completely dependent upon surface water which makes it even more vulnerable to drought than if its supply was comprised of a variety of water supply options. With surface water sources fully exploited and storage opportunities within the urban edge limited alternative water supply options must be more seriously considered and the water governance reformed to accommodate its use. Water governance is the focus of reform because it is the framework for infrastructure planning and therefore controls the resultant system, infrastructure and management. This thesis interrogates the current water governance as the starting point before firstly discussing the proposed incremental approach towards a decentralised, hybrid system for water infrastructure and secondly, identifying specific areas where intervention is necessary for implementation.

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.<br>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.

Thesis (M.S.V.)--University of Toledo, 2004.<br>Typescript. "A thesis [submitted] as partial fulfillment of the requirements of the Master of Science degree in Civil Engineering." Bibliography: leaves 116-121.

With sustainable development as the new overarching goal, urban wastewater system (UWS) managers are now being asked to take all social, economic, technical and environmental facets related to their decisions into account. In this complex decision-making environment, uncertainty can be formidable. Uncertainty is present both in the ways the system is interpreted stochastically, but also in its natural ever-shifting behaviour. This inherent uncertainty leads to the conclusion that better decisions will be made if the decision-making process is adaptive and iterative. UWS decision-support frameworks exist in the literature, but none of them effectively addresses all these needs. Hence, there is a need for an adaptive framework that supports UWS management by addressing aspects of sustainability and uncertainty of various types. The development of such a framework is the main outcome of this work, and is supported by two demonstrative applications presented in this thesis.<br>En el marc de desenvolupament sostenible, els gestors dels sistemes de sanejament han d’incloure factors socials, econòmics, tècnics i ambientals durant la presa de decisions. Donada l’elevada complexitat en la presa de decisions, la incertesa relacionada amb aquests factors pot esdevenir rellevant i per tant s’ha d’incorporar de forma adequada. La incertesa està present no només en la forma d’interpretar el sistema sinó també en el seu comportament natural i canviant. Necessitem processos de decisió que siguin adaptatiu i iteratiu per tal d’assegurar que el sistemes de sanejament mantenen la seva eficàcia durant la seva vida útil. Tot i que existeixen en la bibliografia alguns marcs d’ajuda a la presa de decisions cap d’ells inclou de forma efectiva tots aquests aspectes. Per tant, necessitem disposar d’un marc que ajudi en la gestió dels sistemes de sanejament sota el paradigma de gestió adaptativa al mateix temps que consideri aspectes de sostenibilitat i incertesa de diferent origen. Aquest és l’objectiu principal d’aquest treball, conjuntament amb dos aplicacions de demostració.