Introduktion: Många städer i Sverige har fler lågpunkter i sin terräng och är drabbadevid kraftigt regn. Förtätning i städerna förvärrar ofta problemet ytterligare då mängdenhårdgjorda ytor utökas samtidigt som tillgänglig mark för dagvattenhantering minskar.Detta gör att dagvattenflöden som behöver hanteras kan vara mycket stora och avrinnamycket snabbt. Därför är det viktigt att städerna får till en långsiktig och hållbardagvattenhantering som klarar dagens och framtidens klimatförändring. Denna rapportska undersöka hur Karlstad och Växjö kommun arbetar och planerar för den ökaderisken av skyfall samt studera de olika lösningarna som används idag. Rapporten skaäven identifiera vilka omkringliggande faktorer som påverkar dagvattenlösningarna. Metod: Först har det utfört en litteraturstudie för att fördjupa kunskaper och få en bravetenskaplig grund som är baserad på ämnet. För att kunna svara på frågeställningar såhar det genomförts två fallstudier och tre intervjuer med respondenter från VAavdelningen på Växjö och Karlstad kommun samt en expert. Sedan utfördesdokumentanalys av respektive kommuner utifrån planbeskrivning, hållbarhetsindexsamt dagvattenutredningen för att kunna få så omfattande material som möjligt. Resultat: Planeringen och arbetet har påbörjats genom att en skyfallskartering ochförsta konsekvensanalys framtagits. Ingen fullständig handlingsplan har framställts avde tillfrågade kommunerna. För att komma igång med arbetet ska Karlstad kommunanställa en skyfallssamordnare. Lösningar som används mest i kommunerna ärreningsdammar, utjämningsmagasin, gatuhantering och förnyelse av ledningsnätet.Speciell lösning i Växjö kommun är reduktion av dagvattentaxan. Platsen som skaåtgärdas, kunskap, lagar, tidsåtgång och VA avdelningens samarbete medfastighetsägare och andra avdelningar i kommun är viktiga beståndsdelar som påverkarimplementeringen av olika lösningar. Analys: Av resultatet kan slutsatserna dras att kommunerna arbetar och planerar välmed den ökade risken av skyfall i sårbara lågstråk. Mer arbete kan dock göras genomatt framställa en handlingsplan anpassad efter VA. Vilken lösning som tillämpas berorpå en del faktorer. Klimatförändringen som är en viktig faktor tar kommunerna hänsyntill i planeringen och arbetet genom att säkerhetsfaktor tilläggs fördagvattenanläggningar och vid dimensionering av ledningsnätet. Arbetet fortsättergenom att få ett gott samarbete mellan VA-avdelningen och teknikavdelningarna ikommunen samt fastighetsägare då det ofta leder till en god och noga förberedd lösning.Kommunerna förklarar att använda sig av kosteffektiva lösningar är viktigt dåfinansiering kommer ifrån VA-taxan. Det spekuleras i att en förändring i lagen som gerVA avdelningen möjlighet att få finansiera för skyfalls åtgärder hade minimeratöversvämningsriskerna. Diskussion: Resultatet anses vara användbart då kommunerna kan ta del av varandrasplanering och arbete samt hjälpa varandra i utvecklingen av hållbaradagvattenlösningar. Resultatet främjar en större förståelse kring vilka faktorer somligger till grund för de valda lösningarna. Generaliseringen av resultatet kan sättas ifråga eftersom det är platsspecifikt. Men det går att tillämpa eftersom förståelsen ökarkring hur man kan hantera ett liknande problem på en annan plats eller kommun. / Introduction: Many cities in Sweden have many low points in their terrain and areaffected by heavy rain. Urban sprawl often exacerbates the problem by increasing theamount of paved surfaces while reducing available land for stormwater treatment. Thismeans that stormwater flows that need to be managed can be very heavy and drainquickly. It is therefore important that cities achieve long-term sustainable stormwatermanagement that can cope with current and future climate change. This report willexamine how Karlstad and Växjö municipalities are working and planning for theincreased risk of stormwater and study the different solutions currently in use. Method: This report began with a literature study to deepen knowledge and get a goodbase. In order to answer the research questions, two case studies and three interviewswere conducted with respondents from the Water and Wastewater Departments ofVäxjö and Karlstad Municipality. One expert was also interview. Document analysiswas then carried out based on the plan description, sustainability index and thestormwater study in order to obtain as comprehensive material as possible. Results: The planning and work started with the preparation of a flood mapping and afirst impact assessment. No full action plan has been prepared by the consultedmunicipalities. In order to start the work, Karlstad will employ a rainfall coordinator.Most common solutions used in municipalities are treatment ponds, levellingreservoirs, street management and renewal of the sewerage and stormwater system. Aspecial solution in Växjö is the reduction of stormwater tax. Location, knowledge, laws,time and the cooperation of the water department with property owners and otherdepartments in the municipality are important elements that influence theimplementation of different solutions. Analysis: From the results it can be concluded that the municipalities are working andplanning well with the increased risk of rainfall in low-lying areas. However, morework can be done by producing an action plan adapted to these areas. The solutionapplied depends on a number of factors. These factors are adding safety factors tostormwater facilities and increasing the capacity of the pipeline system. The work iscontinued through good cooperation the different technical facilities in themunicipalities but also property owners as it often leads to a good and carefullyprepared solution. The municipalities explain that using cost-effective solutions isimportant because the funding comes from the water and wastewater departments tax.It is speculated that a change in the law allowing the water and wastewater departmentto receive funding for stormwater measures would have minimized flood risks. Discussion: The results are considered useful because the municipalities can learn fromeach other's planning and work as well as help each other in developing sustainablestormwater solutions. The result promotes a better understanding of the factorsunderlying the chosen solutions. The generalization of the results can be questioned asit is site-specific. However, it can be applied because it increases understanding of howto address a similar problem in another location or municipality.

Nonpoint source (NPS) pollution is one of the leading causes of water quality problems in the United States. Bioretention has become one of the more frequently used stormwater management practices for addressing NPS pollution in urbanized watersheds in New England. Yet despite increased acceptance, bioretention is not widely practiced. This study explores and evaluates the efficacy of bioretention for protecting urban water quality. This research found that numerous monitoring methods are used by researchers and industry experts to assess the effectiveness of stormwater best management practices (BMPs) and low impact development (LID) practices that include bioretention. The two most common methods for analyzing and evaluating water quality data are pollutant removal efficiency and effluent quality. While effluent quality data is useful for characterizing classes of BMP treatment performance on a statistical basis, pollutant removal efficiency is more representative of the actual pollutant load being reduced by the stormwater treatment practice over time, and is used in Total Maximum Daily Load (TMDL) assessments. However, despite this difference, monitoring is still arguably the best method for determining the effectiveness of stormwater treatment practices. Monitoring of bioretention performance results is needed to inform improvements to design standards and guidance to aid state and local municipalities in the proper selection of bioretention/stormwater controls. This study advocates for instituting fine-scale, “safe-to-fail” design experiments as part of an adaptive management process that is used to advance bioretention design guidance and future applications of monitoring practice(s) that target reduction of pollutants in downstream receiving waterbodies. This innovative approach could result in increased use of bioretention in New England urban environments.

Construction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and other impervious surfaces are routinely discharged into ponds for treatment before being released into a receiving water body. Stormwater harvesting from a pond for irrigation of adjacent lands is promoted as one approach to reducing pond discharge while supplementing valuable potable water used for irrigation. The reduction of pond discharge reduces the mass of pollutants in the discharge. In the dissertation, presented is the investigation of the effectiveness of temporary sediment barriers and then, development of a modeling approach to a stormwater harvesting pond to provide a comprehensive stormwater management pollution reduction assessment tool. The first part of the research presents the investigation of the performance efficiencies of silt fence fabrics in turbidity and sediment concentration removal, and the determination of flowthrough-rate on simulated construction sites in real time. Two silt fence fabrics, (1) woven and the other (2) nonwoven were subjected to material index property tests and a series of field-scale tests with different rainfall intensities and events for different embankment slopes on a tilting test-bed. Collected influent and effluent samples were analyzed for sediment concentration and turbidity, and the flow-through-rate for each fabric was evaluated. Test results revealed that the woven and nonwoven silt fence achieved 11 and 56 percent average turbidity reduction iv efficiency, respectively. Each fabric also achieved 20 and 56 percent average sediment concentration removal efficiency, respectively. Fabric flow-through-rates were functions of the rainfall intensity and embankment slope. The nonwoven fabric exhibited higher flow-throughrates than the woven fabric in both field-scale and laboratory tests. In the second part of the study, a Stormwater Harvesting and Assessment for Reduction of Pollution (SHARP) model was developed to predict operation of wet pond used for stormwater harvesting. The model integrates the interaction of surface water and groundwater in a catchment area. The SHARP model was calibrated and validated with actual pond water elevation data from a stormwater pond at Miramar Lakes, Miramar, Florida. Model evaluation showed adequate prediction of pond water elevation with root mean square error between 0.07 and 0.12 m; mean absolute error was between 0.018 and 0.07 m; and relative index of agreement was between 0.74 and 0.98 for both calibration and validation periods. The SHARP model is capable of assessing harvesting safe-yield and discharge from a pond, including the prediction of the percentage of runoff into a harvesting pond that is not discharged. The combination of silt fence and/or polyacrylamide PAM before stormwater harvesting pond in a treatment train for the reduction of pollutants from construction sites has the potential of significantly exceeding a performance standard of 85 percent reduction typically required by local authorities. In fact, the stringent requirement of equaling pre- and post-development pollutant loading is highly achievable by the treatment train approach. The significant contribution from the integration of the SHARP model to the treatment train is that real-time assessment of pollutant loading reduction by volume can be planned and controlled to achieve target performance standards.

The shrinking of permeable areas in favour of urban development is a phenomenon described in both scientific literature and policy documents. Changes in rainfall intensity and frequency following climate change are expected, but predicting the exact magnitude of these changes remains unclear. The uncertainty of what we will have to face in the future and when it will happen causes a blur of activities that may successively influence the mitigation of climate change. This study aims to explore and understand sustainable stormwater management within nature-based solutions (NBS) by reviewing both scientific and grey literature, as well as development plans in a specific area in southern Stockholm. Both risks and benefits of NBS implementation in urban stormwater management have been reviewed and described. Moreover, it is found in the literature that conceptual ambiguities and uncertainties of the NBS concept lead to weaker decision-making and planning processes. The goal of this study was to understand stormwater management recommendations for climate change mitigation, how these recommendations relate to detailed planning documents, what types of solutions are considered and proposed in the planning process, whether there is a link between the NBS and the proposed solutions, and finally, whether spatial analysis can help in the planning process in locating the strengths and weaknesses of the planned construction in flood-prone areas. The results of this study indicates whether the selected detailed development plans follow the recommendations of strategic documents. Detailed planning documents followed the recommendations to a limited extent. Moreover, in terms of spatial analysis, the analysed plans rarely referred to Skyfallsmodell, the model used to represent the flood-risk caused by 100-year rain event. In one of the cases of the early-stage detailed development plan, the new construction area were proposed inside an area with significant risk of flooding. The use of spatial analysis could help urban planners to identify both areas unsuitable for development and locate places suitable for NBS implementation. / Minskningen av genomsläppliga markområden till förmån för stadsutveckling är ett fenomen som beskrivs i både vetenskaplig litteratur och policydokument. Förändringar i nederbördsintensitet och storlek efter klimatförändringar förväntas, men det är fortfarande svårt att förutsäga den exakta storleken på dessa förändringar. Osäkerheten om vad vi kommer att behöva möta i framtiden och när det kommer att hända orsakar en oklarhet kring vilka aktiviteter som kommer att kunna påverka och mildra effekterna av klimatförändringarna. Denna studie syftar till att utforska och förstå hållbar dagvattenhantering genom naturbaserade lösningar (NBS) genom att granska både vetenskaplig och grå litteratur, samt utvecklingsplaner i ett specifikt område i södra Stockholm. Både risker och fördelar med NBS-implementering i urban dagvattenhantering har granskats och beskrivits. Dessutom framgår av litteraturen att begreppsmässiga oklarheter och osäkerheter i NBS-begreppet leder till svagheter i beslutsfattande och planeringsprocesser. Målet med denna studie var att förstå rekommendationer för dagvattenhantering för att mildra klimatförändringar, hur dessa rekommendationer relaterar till detaljerade planeringsdokument, vilka typer av lösningar som övervägs och föreslås i planeringsprocessen, om det finns en koppling mellan NBS och de föreslagna lösningarna, och slutligen - om rumslig analys kan hjälpa till i planeringsprocessen för att lokalisera styrkor och svagheter med den planerade konstruktionen i översvämningsutsatta områden. Resultaten av denna studie indikerar hur de valda detaljutvecklingsplanerna följer rekommendationerna i strategiska dokument. Detaljerade planeringshandlingar följde rekommendationerna i begränsad omfattning. Dessutom, när det gäller rumslig analys, hänvisade de analyserade planerna sällan till Skyfallsmodellen, som används för att representera översvämningsrisken orsakad av 100-årsregn. I ett av fallen med en tidig detaljplanen föreslogs nybyggnadsområdet inom ett område med stor risk för översvämning. Användningen av rumslig analys skulle kunna hjälpa stadsplanerare att identifiera både områden som är olämpliga för utveckling och att lokalisera platser som är lämpliga för implementering av NBS.

further development of the simple and promising analytical probabilistic approach / Urban stormwater management aims at mitigating the adverse impacts of urbanization. Hydrological models are used in support of stormwater management planning and design. There are three main approaches that can be applied for this modeling purpose: (1) continuous simulation approach which is accurate but time-consuming; (2) design storm approach, which is widely used and its accuracy highly depends on the selected antecedent moisture conditions and temporal distribution of design storms; and (3) the analytical probabilistic approach which is recently developed and still not used in practice. Although it is time-effective and it can produce results as accurate as the other two approaches; the analytical probabilistic approach requires further developments in order to make it more reliable and accurate. For this purpose, three subtopics are investigated in this thesis. (1) Rainfall data analysis as required by the analytical probabilistic approach with emphasis on testing the exponentiality of rainfall event duration, volume and interevent time (i.e., time separating it from its preceding rainfall event). A goodness-of-fit testing procedure that is suitable for this kind of data analysis was proposed. (2) Derivation of new analytical probabilistic models for peak discharge rate incorporating trapezoidal and triangular hydrograph shapes in order to include all possible catchment’s responses. And (3) the infiltration process is assumed to continue until the end of the rainfall event; however, the soil may get saturated earlier and the excess amount would contribute to the runoff volume which may have adverse impact if not taken into consideration. Thus, in addition to the infiltration process, the saturation excess runoff is also included and new models for flood frequencies are developed. All the models developed in this thesis are tested and compared to methods used in practice, reasonable results were obtained. / Thesis / Doctor of Philosophy (PhD) / Urban stormwater management aims at mitigating the adverse impacts of urbanization. Hydrological models are used in support of stormwater management planning and design. The analytical probabilistic stormwater management model (APSWM) is a promising tool for planning and design analysis. The purpose of this thesis is to further develop APSWM in order to make it more reliable and accurate. First, a clear procedure for rainfall data analysis as required by APSWM is provided. Second, a new APSWM is derived incorporating other runoff temporal-distribution patterns. Finally, the possibility of soil layer saturation while it is still raining is added to the model. All the models developed in this thesis are tested and compared to methods used in engineering practice, reasonable results were obtained.

In urban areas, trees are often planted in bare soil sidewalk openings (tree pits) which recently are being covered with permeable pavements. Pavements are known to alter soil moisture and temperature, and may have implications for tree growth, root development and depth, drought resilience, and sidewalk lifting. Furthermore, tree pits are often the only unsealed soil surface and are important for water exchange between soil and atmosphere. Therefore, covering tree pits with pavement, even permeable, may have implications for the urban water balance and stormwater management. A better understanding of permeable pavement on tree pavement soil system functioning can inform improved tree pit and street design for greater sustainability of urban environments. We conducted experiments at two sites in Virginia, USA (Mountains and Coastal Plain) with different climate and soil. At each location, we constructed 24 tree pits in a completely randomized experiment with two factors: paved with resin-bound porous-permeable pavement versus unpaved, and planted with Platanus x acerifolia 'Bloodgood' versus unplanted (n = 6). We measured tree stem diameter, root growth and depth, and soil water content and temperature over two growing seasons. We also monitored tree sap flow one week in June 2017 at the Mountains. In addition, we calibrated and validated a soil water flow model, HYDRUS-1D, to predict soil water distribution for different rooting depths, soil textures and pavement thicknesses. Trees in paved tree pits grew larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster under pavement, possibly due to the increased soil water content and the extended root growing season (14 more days). Tree transpiration was 33% of unpaved and planted pit water outputs, while it was 64% for paved and planted pits. In June 2016, planted pits had decreased root-zone water storage, while unplanted pits showed increased storage. A water balance of the entire experimental site showed overall decreased soil water storage due to tree water extraction becoming the dominant factor. HYDRUS-1D provided overall best results for model validation at 10 cm depth from soil surface (NSE = 0.447 for planted and paved tree pits), compared to 30- and 60 cm depths. HYDRUS-1D simulations with greater pavement thickness resulted in changes in predicted soil water content at the Coastal Plain, with higher values at 10- and 30-cm depths, but lower values at 60-cm depth. At the Mountains, virtually no difference was observed, possibly due to different soil texture (sandy vs clayey). Tree pits with permeable pavement accelerated tree establishment, but promoted shallower roots, possibly increasing root-pavement conflicts and tree drought susceptibility. Paved tree pits resulted in larger trees, increasing tree transpiration, but reduced soil evaporation compared to unpaved pits. Larger bare soil pits surrounded by permeable pavement might yield the best results to improve urban stormwater retention. Also, HYDRUS 1D was successful at simulating soil water content at 10-cm depth and may be valuable to inform streetscape design and planning. / PHD / Trees in cities are often planted in pavement cutouts (tree pits) that are usually the only available area for water exchange between soil and atmosphere. Tree pits are typically covered with a variety of materials, including permeable pavement. Pavements are known to modify soil water distribution and temperature, affecting tree growth, rooting depth, drought resilience, and sidewalk lifting. A better understanding of this system can inform tree pit and street design for greater sustainability. We constructed 24 tree pits at each of two regions in Virginia, USA (Mountains and Coastal Plain). These tree pits were paved with permeable pavement or unpaved, and planted with London Plane or unplanted. We measured stem diameter, root growth, and soil water content and temperature over two years and tree sap flow for one week in summer (Mountains only). We also used a soil water flow model, HYDRUS-1D, to predict water distribution for different rooting depths, soil textures and pavement thicknesses. After the first growing season trees in pavement were larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster under pavement, possibly due to increased soil water content and a 14-day increase in root growing season. Also, in June 2017, tree transpiration was 33% of unpaved-and-planted pit water outputs, and 64% of paved-and-planted pits. In June 2016, root-zone water storage decreased in planted pits but increased in unplanted pits. When considering the entire experimental site, soil water storage decreased, with tree water extraction being the dominant factor. HYDRUS-1D performed better at 10-cm soil depth than at 30- and 60-cm depths. At the Coastal Plain, HYDRUS-1D predicted higher soil water content at 10- and 30-cm depths with increased pavement thickness, but lower values at 60-cm depth. At the Mountains, there was no effect, possibly due to higher clay content. Permeable pavement accelerated tree establishment, but promoted shallower roots, increasing drought susceptibility and risk for root-pavement conflicts. Pavement resulted in larger trees and greater transpiration, but reduced soil evaporation. Larger bare-soil pits surrounded by permeable pavement might optimize stormwater retention.

L’implantation répandue de nouveaux quartiers résidentiels sur le territoire de la périphérie urbaine est en partie responsable de la baisse du couvert végétal et de l’augmentation des surfaces imperméables à grande échelle. Les villes sont maintenant aux prises avec une augmentation constante de la production de ruissellement qu'elles doivent gérer au moyen d’un vaste réseau d’égouts et de canalisations. Des données sur les impacts de ces modèles de quartier résidentiel nous révèlent que cette forme d’habitat provoque la dégradation des milieux naturels et aquatiques. La présente étude vise à mettre à l’épreuve la stratégie d’aménagement de l’Open space design en comparant l’effet de trois situations d’aménagement d’ensembles résidentiels sur le coefficient de ruissellement pondéré (Cp). Les trois situations étudiées sont 1 : le développement actuel tel que conçu par le promoteur, 2 : un scénario de quartier visant la préservation des cours d’eau existants ainsi qu’une réduction des lots et des surfaces imperméables et 3 : un quartier avec des types d’habitation plus denses. Les coefficients pondérés obtenus sont respectivement de 0,50 pour le quartier actuel, de 0,40 pour le scénario 1 et de 0,34 pour le scénario 2. Au terme de cet exercice, il apparaît, d’une part, que la densification du bâti, la nature des surfaces et l’organisation spatiale peuvent concourir à diminuer la production de ruissellement d’un quartier. Cette étude permet de situer l’importance de la gestion du ruissellement dans la planification et l’aménagement du territoire. / The widespread introduction of new residential developments in the urban periphery is partly responsible for declining vegetation cover and a large scale increase in impervious surfaces. Cities are now grappling with a constant increase in runoff, which they have to manage through a vast network of sewers and drains. Data on the impacts of current residential models reveal that this form of development causes the degradation of natural and aquatic environments. The present study aims to test Open space design strategy by comparing the effect of three development situations on the weighted runoff coefficient (Cw). The three situations are 1: the actual development as conceived by the project’s promoter; 2: development aimed at preserving existing streams, reducing lot sizes and impervious surfaces; and 3: a higher-density cluster development plan. The weighted coefficients obtained are 0.50 for scenario 1, 0.40 for scenario 2 and 0.34 for scenario 3. As a result, it appears that the density of the structures, the nature of the surfaces and the spatial organization can all contribute to reducing the runoff in a given area. This study underlines the importance of runoff management in planning and land use.

L’implantation répandue de nouveaux quartiers résidentiels sur le territoire de la périphérie urbaine est en partie responsable de la baisse du couvert végétal et de l’augmentation des surfaces imperméables à grande échelle. Les villes sont maintenant aux prises avec une augmentation constante de la production de ruissellement qu'elles doivent gérer au moyen d’un vaste réseau d’égouts et de canalisations. Des données sur les impacts de ces modèles de quartier résidentiel nous révèlent que cette forme d’habitat provoque la dégradation des milieux naturels et aquatiques. La présente étude vise à mettre à l’épreuve la stratégie d’aménagement de l’Open space design en comparant l’effet de trois situations d’aménagement d’ensembles résidentiels sur le coefficient de ruissellement pondéré (Cp). Les trois situations étudiées sont 1 : le développement actuel tel que conçu par le promoteur, 2 : un scénario de quartier visant la préservation des cours d’eau existants ainsi qu’une réduction des lots et des surfaces imperméables et 3 : un quartier avec des types d’habitation plus denses. Les coefficients pondérés obtenus sont respectivement de 0,50 pour le quartier actuel, de 0,40 pour le scénario 1 et de 0,34 pour le scénario 2. Au terme de cet exercice, il apparaît, d’une part, que la densification du bâti, la nature des surfaces et l’organisation spatiale peuvent concourir à diminuer la production de ruissellement d’un quartier. Cette étude permet de situer l’importance de la gestion du ruissellement dans la planification et l’aménagement du territoire. / The widespread introduction of new residential developments in the urban periphery is partly responsible for declining vegetation cover and a large scale increase in impervious surfaces. Cities are now grappling with a constant increase in runoff, which they have to manage through a vast network of sewers and drains. Data on the impacts of current residential models reveal that this form of development causes the degradation of natural and aquatic environments. The present study aims to test Open space design strategy by comparing the effect of three development situations on the weighted runoff coefficient (Cw). The three situations are 1: the actual development as conceived by the project’s promoter; 2: development aimed at preserving existing streams, reducing lot sizes and impervious surfaces; and 3: a higher-density cluster development plan. The weighted coefficients obtained are 0.50 for scenario 1, 0.40 for scenario 2 and 0.34 for scenario 3. As a result, it appears that the density of the structures, the nature of the surfaces and the spatial organization can all contribute to reducing the runoff in a given area. This study underlines the importance of runoff management in planning and land use.

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.

Förekomsten av vattenrelaterade problem som extrem nederbörd, översvämningar, torka och vattenbrist kommer att öka i urbana områden till följd av de globala klimatförändringarna. Sponge city-konceptet är ett urbant dagvattenhanteringssystem som lanserades i Kina och syftar till att förbättra vattenhanteringen i städer genom att återställa stadens kapacitet att absorbera, infiltrera, lagra och rena vatten. Den här studien syftade till att undersöka om sponge city-konceptet hade kunnat implementeras i Malmö genom att besvara frågeställningen ” Vilka möjligheter respektive hinder finns det för Malmö att implementera sponge city-konceptet?”. Genom en systematisk litteraturstudie och innehållsanalys i kombination med det teoretiska ramverket som baserades på konceptet sårbarhet för klimatförändringar visade resultatet på att det både finns en del möjligheter men också hinder. Det huvudsakliga hindret som identifierades är att en stor del av marken i Malmö består av täta moränleror vilket utgör ett hinder för de infiltrationsåtgärder som ingår i sponge city-konceptet. Några möjligheter som identifierades är att sponge city-konceptet kan minska känsligheten för skada som uppstår i förhållande till exponeringsnivån, samt att Malmös anpassningskapacitet är relativt hög. På grund av att den här studien enbart undersökte specifika fysiska/miljömässiga aspekter inom sponge city-konceptet krävs däremot fler studier som tar hänsyn till fler aspekter om en implementering av konceptet skulle bli aktuell. / The occurrence of water related problems such as extreme precipitation, floods, drought and water scarcity will increase in urban areas as a result of global climate change. The sponge city-concept is an urban stormwater system launched in China and aims to improve the water management in cities by restoring the city’s capacity to absorb, infiltrate, store and purify water. This study aimed to investigate if the sponge city-concept could be implemented in Malmö by answering the question “What possibilities and obstacles exist for Malmö to implement the sponge city-concept?”. Through a systematic literature review and content analysis in combination with the theoretical framework, which was based on the concept climate change vulnerability, the results showed that there are some possibilities but also obstacles. The main obstacle that was identified is that the ground in Malmö largely consists of dense moraines which forms an obstacle for the infiltration measures that are included in the sponge city-concept. Some possibilities that were identified is that the sponge city-concept can decrease the sensitivity to harm that occurs in relation to the exposure level but also that Malmö’s adaptation capacity is relatively high. However, because this study only investigated specific physical/environmental aspects within the sponge city-concept, more studies that consider more aspects are required if an implementation of the concept would become prevailing.