Med målet att uppnå vattenkvalité av god status inom hela EU införde Europaparlamentet år 2000 ramdirektivet för vatten (2000/60/EC), även kallat Vattendirektivet. För att uppnå god vattenstatus sätts mål i form av ”miljökvalitetsnormer”(MKN) på vattendrag, sjöar, kustvatten och grundvatten inom varje län och kommun. Dessa ska beaktas vid framtagandet av nya detaljplaner vilket är ett juridiskt gällande dokument där den tillåtna exploateringen av ett område fastställs. I detaljplanen ska planens påverkan på möjligheterna att uppnå MKN för vatten utredas och presenteras. Det saknas dock tydliga riktlinjer för hur denna bedömning ska göras och vilka aspekter som ska ingå i utredningen. I de fall planen medför att målen i form av MKN riskeras att inte uppnås är det länsstyrelsens uppgift att hindra planen från att godkännas. Syftet med studien är att utreda vad som är viktigt i arbetet att ta fram en detaljplan som beaktar MKN för vatten och hur kommuner och länsstyrelser upplever arbetet. Målet är att undersöka det övergripande arbetet och därefter fokusera på den bedömning som görs av vilken påverkan på MKN en plan medför. Detta för att ge en bild av hur arbetet sker i dagsläget och belysa de utmaningar och förbättringsmöjligheter som finns. Studien avgränsas geografisk till länsstyrelserna inom Norra Östersjöns vattendistrikt och kommunerna i Stockholms län. För att undersöka det ovannämnda genomfördes en förstudie bestående av en intervjustudie riktad till konsulter och anställda på kommun och länsstyrelser, och en litteraturstudie. Förstudien ledde fram till formuleringen av frågor i enkätstudien. Enkätstudien bestod av två delar där den första riktade sig till kommuner i Stockholms län och den andra till länsstyrelserna i Norra Östersjöns vattendistrikt. Resultatet från studien bidrog till att identifiera viktiga steg i processen att ta fram en detaljplan som följer satta MKN. Även svårigheter kopplade till de olika processtegen framkom. Uppföljning visade sig vara ett steg som inte genomförs i så stor utsträckning men som troligtvis kan förbättra situationen genom att bidra med data och kvalitetssäkring av metodiken. Bedömningen som görs av hur en plan påverkar möjligheten att uppfylla MKN sammanställdes i några nyckelsteg. De flesta svårigheter som upplevs av de kommunanställda är kopplade till att utföra den här bedömningen. Främst är det osäkerheter i metod och modelleringsverktyg tillsammans med ofullständigt underlagsmaterial som bidrar till svårigheterna. Det preliminära åtgärdsprogram som presenterats våren 2016 av Vattenmyndigheten inför nästa 6-åriga arbetscykel bidrar förhoppningsvis med att vägledningsmaterial och tydligare riktlinjer tas fram. Detta efterfrågades från flera håll i enkätstudien. Förutom det som åtgärdsprogrammet adresserar ses ett behov av mer utbildning och samverkan av och mellan aktörer. Beräkningsmetoder och underlag som används behöver även ses över och det behöver finnas en tydligare samsyn på hur en detaljplansplans påverkan på MKN ska bestämmas. / With the goal of high quality recipients within the European Union the European Water Framework Directive (WFD; 2000/60/EC) was initiated in the year of 2000. In order to achieve water of high quality, goals have been established under the definition of Environmental Quality Standards (EQS). These are defined for lakes, rivers and other water bodies within each municipality. The EQS are defined as a level that are to be reached until a defined year. The EQS are to be kept in mind when zoning is carried out within a municipality. Zoning allows for strategic use of land and water within the municipality and is an important part in the work of achieving the EQS. If a zoning plan does not meet the EQS the plan should not be adopted. The county government should audit plans before they are approved to make sure the chance of reaching the EQS are not hindered by the plan. The aim of this study is to investigate which important factors that come into play when a zoning plan is created that will meet the EQS. The aim is also to get an understanding of the work from the municipalities perspective as well as from the viewpoint of the county government. Both the overall perspective and the more detailed field of assessing the impact from a zoning plan is to be analyzed. In the end the goal is to give an overview of how the work is done today, which difficulties that are experienced as well as improvements that could be needed. The study is focused upon the county governments within the North Baltic Sea basin and the municipalities within Stockholm county. Semi-structured interviews and a literature review were conducted followed by a survey study in order to address the research questions. The survey study was directed towards the county governments and municipalities within the geographical study area mentioned above. From the methods described above data was collected which resulted in the identification of important steps in the process of making zoning with consideration of the EQS. Also difficulties connected to each phase were identified. The work of follow-up and monitoring was found only to be carried out to a limited extent but is believed to support several important functions in the work, if improved. The impact assessment of zoning on water quality and EQS was found to be one of the more difficult parts of the work with the WFD. Foremost, this process is connected to many uncertainties in the method of calculation but also due to limited data available in some cases. Information needed is for example the current water quality and the levels of pollution connected to different land uses of the area. More developed guidelines and support from central authorities was requested by several participants of the survey. Hopefully the Water authorities’ planned action program for the next 6-year work cycle, will result in this. However, more investigations and studies are needed in order to improve and minimize uncertainties in the methods used to calculate impact from zoning on water quality. More education and cooperation between municipalities, county governments and agencies with issues connected to implementing the WFD is needed as well. Overall more consensus is needed in how the work can be carried out while meeting both environmental and societal goals.

Increasing global mean temperature or global warming has the potential to affect the hydrologic cycle. In the 21st century, according to the UN Intergovernmental Panel on Climate Change (IPCC), alterations in the frequency and magnitude of high intensity rainfall events are very likely. Increasing trend of urbanization across the globe is also noticeable, simultaneously. These changes will have a great impact on water infrastructure as well as environment in urban areas. One of the impacts may be the increase in frequency and extent of flooding. India, in the recent years, has witnessed a number of urban floods that have resulted in huge economic losses, an instance being the flooding of Mumbai in July, 2005. To prevent catastrophic damages due to floods, it has become increasingly important to understand the likely changes in extreme rainfall in future, its effect on the urban drainage system, and the measures that can be taken to prevent or reduce the damage due to floods. Reliable estimation of future design rainfall intensity accounting for uncertainties due to climate change is an important research issue. In this context, rainfall intensity-duration-frequency (IDF) relationships are one of the most extensively used hydrologic tools in planning, design and operation of various drainage related infrastructures in urban areas. There is, thus, a need for a study that investigates the potential effects of climate change on IDF relationships. The main aim of the research reported in this thesis is to investigate the effect of climate change on Intensity-Duration-Frequency relationship in an urban area. The rainfall in Bangalore City is used as a case study to demonstrate the applications of the methodologies developed in the research Ahead of studying the future changes, it is essential to investigate the signature of changes in the observed hydrological and climatological data series. Initially, the yearly mean temperature records are studied to find out the signature of global warming. It is observed that the temperature of Bangalore City shows an evidence of warming trend at a statistical confidence level of 99.9 %, and that warming effect is visible in terms of increase of minimum temperature at a rate higher than that of maximum temperature. Interdependence studies between temperature and extreme rainfall reveal that up to a certain range, increase in temperature intensifies short term rainfall intensities at a rate more than the average rainfall. From these two findings, it is clear that short duration rainfall intensities may intensify in the future due to global warming and urban heat island effect. The possible urbanization signatures in the extreme rainfall in terms of intensification in the evening and weekends are also inferred, although inconclusively. The IDF relationships are developed with historical data and changes in the long term daily rainfall extreme characteristics are studied. Multidecedal oscillations in the daily rainfall extreme series are also examined. Further, non-parametric trend analyses of various indices of extreme rainfall are carried out to confirm that there is a trend of increase in extreme rainfall amount and frequency, and therefore it is essential to the study the effects of climate change on the IDF relationships of the Bangalore City. Estimation of future changes in rainfall at hydrological scale generally relies on simulations of future climate provided by Global Climate Models (GCMs). Due to spatial and temporal resolution mismatch, GCM results need to be downscaled to get the information at station scale and at time resolutions necessary in the context of urban flooding. The downscaling of extreme rainfall characteristics in an urban station scale pose the following challenges: (1) downscaling methodology should be efficient enough to simulate rainfall at the tail of rainfall distribution (e.g., annual maximum rainfall), (2) downscaling at hourly or up to a few minutes temporal resolution is required, and (3) various uncertainties such as GCM uncertainties, future scenario uncertainties and uncertainties due to various statistical methodologies need to be addressed. For overcoming the first challenge, a stochastic rainfall generator is developed for spatial downscaling of GCM precipitation flux information to station scale to get the daily annual maximum rainfall series (AMRS). Although Regional Climate Models (RCMs) are meant to simulate precipitation at regional scales, they fail to simulate extreme events accurately. Transfer function based methods and weather typing techniques are also generally inefficient in simulating the extreme events. Due to its stochastic nature, rainfall generator is better suited for extreme event generation. An algorithm for stochastic simulation of rainfall, which simulates both the mean and extreme rainfall satisfactorily, is developed in the thesis and used for future projection of rainfall by perturbing the parameters of the rainfall generator for the future time periods. In this study, instead of using the customary two states (rain/dry) Markov chain, a three state hybrid Markov chain is developed. The three states used in the Markov chain are: dry day, moderate rain day and heavy rain day. The model first decides whether a day is dry or rainy, like the traditional weather generator (WGEN) using two transition probabilities, probabilities of a rain day following a dry day (P01), and a rain day following a rain day (P11). Then, the state of a rain day is further classified as a moderate rain day or a heavy rain day. For this purpose, rainfall above 90th percentile value of the non-zero precipitation distribution is termed as a heavy rain day. The state of a day is assigned based on transition probabilities (probabilities of a rain day following a dry day (P01), and a rain day following a rain day (P11)) and a uniform random number. The rainfall amount is generated by Monte Carlo method for the moderate and heavy rain days separately. Two different gamma distributions are fitted for the moderate and heavy rain days. Segregating the rain days into two different classes improves the process of generation of extreme rainfall. For overcoming the second challenge, i.e. requirement of temporal scales, the daily scale IDF ordinates are disaggregated into hourly and sub-hourly durations. Disaggregating continuous rainfall time series at sub-hourly scale requires continuous rainfall data at a fine scale (15 minute), which is not available for most of the Indian rain gauge stations. Hence, scale invariance properties of extreme rainfall time series over various rainfall durations are investigated through scaling behavior of the non-central moments (NCMs) of generalized extreme value (GEV) distribution. The scale invariance properties of extreme rainfall time series are then used to disaggregate the distributional properties of daily rainfall to hourly and sub-hourly scale. Assuming the scaling relationships as stationary, future sub-hourly and hourly IDF relationships are developed. Uncertainties associated with the climate change impacts arise due to existence of several GCMs developed by different institutes across the globe, climate simulations available for different representative concentration pathway (RCP) scenarios, and the diverse statistical techniques available for downscaling. Downscaled output from a single GCM with a single emission scenario represents only a single trajectory of all possible future climate realizations and cannot be representative of the full extent of climate change. Therefore, a comprehensive assessment of future projections should use the collective information from an ensemble of GCM simulations. In this study, 26 different GCMs and 4 RCP scenarios are taken into account to come up with a range of IDF curves at different future time periods. Reliability ensemble averaging (REA) method is used for obtaining weighted average from the ensemble of projections. Scenario uncertainty is not addressed in this study. Two different downscaling techniques (viz., delta change and stochastic rainfall generator) are used to assess the uncertainty due to downscaling techniques. From the results, it can be concluded that the delta change method under-estimated the extreme rainfall compared to the rainfall generator approach. This study also confirms that the delta change method is not suitable for impact studies related to changes in extreme events, similar to some earlier studies. Thus, mean IDF relationships for three different future extreme events, similar to some earlier studies. Thus, mean IDF relationships for three different future periods and four RCP scenarios are simulated using rainfall generator, scaling GEV method, and REA method. The results suggest that the shorter duration rainfall will invigorate more due to climate change. The change is likely to be in the range of 20% to 80%, in the rainfall intensities across all durations. Finally, future projected rainfall intensities are used to investigate the possible impact of climate change in the existing drainage system of the Challaghatta valley in the Bangalore City by running the Storm Water Management Model (SWMM) for historical period, and the best and the worst case scenario for three future time period of 2021–2050, 2051–2080 and 2071–2100. The results indicate that the existing drainage is inadequate for current condition as well as for future scenarios. The number of nodes flooded will increase as the time period increases, and a huge change in runoff volume is projected. The modifications of the drainage system are suggested by providing storage pond for storing the excess high speed runoff in order to restrict the width of the drain The main research contribution of this thesis thus comes from an analysis of trends of extreme rainfall in an urban area followed by projecting changes in the IDF relationships under climate change scenarios and quantifying uncertainties in the projections.

Made available in DSpace on 2016-03-15T19:22:40Z (GMT). No. of bitstreams: 1 Claudete Gebara Jose Callegaro.pdf: 32253053 bytes, checksum: fc08e149c9973e9e45ffe5687f131952 (MD5) Previous issue date: 2014-11-04 / There are many centuries that the rain, in the city, is not understood as life ; it incorporates road and health infrastructure, confined to gutters, manholes, underground galleries, returning to people perception like floods. Nowadays, the understanding about eco-systemic relationships brings new models for managing urban storm water, in the way of bioclimatic architecture, designing with nature, with contemporary principles of environmental comfort in the cities, i. e., sustainable urban development. The speech is ready; how to transfer theory into practice is one of the objectives of this work. Some places in the world have adopted this paradigm and developed methodology for public and private actions, according to a model called the green infrastructure system. Professionals in individual works also believe in that path, contributing with creative design, showing the model potential. By this principle, every place has its unique design, according to its physical territory and the cultural characteristics of its society. Considering that joint urban operations are the most advanced in urban policy for development, in Brazil, do they incorporate the urban sustainability principles brought by the green infrastructure model? That is what will be analyzed, in reference to the Água Espraiada Joint Urban Operation, in São Paulo. / A chuva, nas cidades, deixou por muitos séculos de ser entendida como vida e passou a incorporar a infraestrutura viária e sanitária, confinada a sarjetas, bueiros, galerias subterrâneas, retornando à percepção da população sob a forma de enchentes. Com a compreensão que se tem hoje sobre as relações ecológico-sistêmicas, novos modelos de gestão das águas pluviais urbanas surgem, consonantes com a arquitetura bioclimática, com a linha de pensamento de desenho com a natureza, com os preceitos contemporâneos do conforto ambiental nas cidades, ou seja, do desenvolvimento urbano sustentável. O discurso está pronto; como transferir a teoria para a prática é um dos objetivos deste trabalho. Alguns lugares no mundo já adotam tais paradigmas e vêm desenvolvendo metodologia para ações públicas e privadas, segundo um modelo denominado sistema de infraestrutura verde. Profissionais em obras individuais também apostam nesse caminho, contribuindo com projetos criativos, mostrando o potencial do modelo. Por esse princípio, cada lugar tem seu projeto único, seja pelas condições físicas de seu território, seja pelas características culturais de sua sociedade. Considerando-se que as operações urbanas consorciadas são o instrumento mais avançado como política urbana em prol do desenvolvimento, no Brasil, até que ponto elas incorporam os preceitos de sustentabilidade urbana trazidos pelo modelo de infraestrutura verde? É o que se analisará, tomando como referência a Operação Urbana Consorciada Água Espraiada, em São Paulo.

Les modèles de Rejets Urbains par Temps de Pluie (MRUTP) de Matières en Suspension (MES) dans les systèmes d’assainissement urbains sont essentiels pour des raisons scientifiques, environnementales, opérationnelles et réglementaires. Néanmoins, les MRUTP ont été largement mis en question, surtout pour reproduire des données mesurées en continu à l’exutoire des grands bassins versants. Dans cette thèse, trois limitations potentielles des MRUTP traditionnels ont été étudiées dans un bassin versant de 185 ha (Chassieu, France), avec des mesures en ligne de 365 événements pluvieux : a) incertitudes des données dû aux conditions sur le terrain, b) incertitudes dans les modèles hydrologiques et mesures de pluie et c) incertitudes dans les structures traditionnelles des MRUTP. Ces aspects sont approfondis dans six apports séparés, dont leurs résultats principaux peuvent être synthétisés comme suites : a) Acquisition et validation des données : (i) quatre stratégies d’échantillonnage pendant des événements pluvieux sont simulées et évaluées à partir de mesures en ligne de MES et débit. Les intervalles d’échantillonnage recommandés sont de 5 min, avec des erreurs moyennes entre 7 % et 20 % et des incertitudes sur ces erreurs d’environ 5 %, selon l’intervalle d’échantillonnage; (ii) la probabilité de sous-estimation de la concentration moyenne dans la section transversale du réseau est estimée à partir de deux méthodologies. Une méthodologie montre des sous-estimations de MES plus réelles (vers 39 %) par apport à l'autre (vers 269 %). b) Modèles hydrologiques et mesures de pluie : (iii) une stratégie d’estimation de paramètres d’un modèle conceptuel pluie-débit est proposée, en analysant la variabilité des paramètres optimaux obtenus à partir d’un calage Bayésien évènement-par-évènement; (iv) une méthode pour calculer les précipitations moyennes sur un bassin versant est proposée, sur la base du même modèle hydrologique et les données de débit. c) MRUTP (pollutographes) : (v) la performance de modélisation à partir du modèle traditionnel courbe d’étalonnage (RC) a été supérieur aux différents modèles linéaires de fonctions de transfert (TF), surtout en termes de parcimonie et précision des simulations. Aucune relation entre les potentielles erreurs de mesure de la pluie et les conditions hydrologiques définies en (iii) et (iv) avec les performances de RC et TFs n’a pu être établie. Des tests statistiques renforcent que l’occurrence des évènements non-représentables par RC ou TF au cours de temps suit une distribution aléatoire (indépendante de la période sèche précédente); (vi) une méthode de reconstruction Bayésienne de variables d’état virtuelles indique que des processus potentiellement manquants dans une description RC sont ininterprétables en termes d’un unique état virtuel de masse disponible dans le bassin versant qui diminue avec le temps, comme nombre de modèles traditionnels l’ont supposé. / Total Suspended Solids (TSS) stormwater models in urban drainage systems are often required for scientific, legal, environmental and operational reasons. However, these TSS stormwater traditional model structures have been widely questioned, especially when reproducing data from online measurements at the outlet of large urban catchments. In this thesis, three potential limitations of traditional TSS stormwater models are analyzed in a 185 ha urban catchment (Chassieu, Lyon, France), by means 365 rainfall events monitored online: a) uncertainties in TSS data due to field conditions; b) uncertainties in hydrological models and rainfall measurements and c) uncertainties in the stormwater quality model structures. These aspects are investigated in six separate contributions, whose principal results can be summarized as follows: a) TSS data acquisition and validation: (i) four sampling strategies during rainfall events are simulated and evaluated by online TSS and flow rate measurements. Recommended sampling time intervals are of 5 min, with average sampling errors between 7 % and 20 % and uncertainties in sampling errors of about 5 %, depending on the sampling interval; (ii) the probability of underestimating the cross section mean TSS concentration is estimated by two methodologies. One method shows more realistic TSS underestimations (about 39 %) than the other (about 269 %). b) Hydrological models and rainfall measurements: (iii) a parameter estimation strategy is proposed for conceptual rainfall-runoff model by analyzing the variability of the optimal parameters obtained by single-event Bayesian calibrations, based on clusters and graphs representations. The new strategy shows more performant results in terms of accuracy and precision in validation; (iv) a methodology aimed to calculate “mean” areal rainfall estimation is proposed, based on the same hydrological model and flow rate data. Rainfall estimations by multiplying factors over constant-length time window and rainfall zero records filled with a reverse model show the most satisfactory results compared to further rainfall estimation models. c) Stormwater TSS pollutograph modelling: (v) the modelling performance of the traditional Rating Curve (RC) model is superior to different linear Transfer Function models (TFs), especially in terms of parsimony and precision of the simulations. No relation between the rainfall corrections or hydrological conditions defined in (iii) and (iv) with performances of RC and TFs could be established. Statistical tests strengthen that the occurrence of events not representable by the RC model in time is independent of antecedent dry weather conditions; (vi) a Bayesian reconstruction method of virtual state variables indicate that potential missing processes in the RC description are hardly interpretable as a unique state of virtual available mass over the catchment decreasing over time, as assumed by a great number of traditional models.

Bibliography :leaves 158-171. A monitoring program, funded by the South Australian government (through the former MFP Development Corporation), was established to monitor the quality and quantity of storm water entering and leaving the wetland. This study formed part of the funded program. Simple regression models were developed; and will assist in the monitoring of performance of the wetland to alleviate the pollutant load into the Barker Inlet.

In order to better understand runoff characteristics from natural gas well sites in north central Texas, the City of Denton, with assistance through an EPA funded 104b3 Water Quality Cooperative Agreement, monitored storm water runoff from local natural gas well sites. Storm water runoff was found to contain high concentrations of total suspended solids (TSS). Observed TSS concentrations resulted in sediment loading rates that are similar to those observed from typical construction activities. Petroleum hydrocarbons, in contrast, were rarely detected in runoff samples. Heavy metals were detected in concentrations similar to those observed in typical urban runoff. However, the concentrations observed at the gas well sites were higher than those measured at nearby reference sites. Storm water runoff data collected from these sites were used to evaluate the effectiveness of the water erosion prediction project (WEPP) model for predicting runoff and sediment from these sites. Runoff and sediment predictions were adequate; however, rainfall simulation experiments were used to further characterize the portion of the site where drilling and extraction operations are performed, referred to as the "pad site." These experiments were used to develop specific pad site erosion parameters for the WEPP model. Finally, version 2 of the revised universal soil loss equation (RUSLE 2.0) was used to evaluate the efficiency of best management practices (BMPs) for natural gas well sites. BMP efficiency ratings, which ranged from 52 to 93%, were also evaluated in the context of site management goals and implementation cost, demonstrating a practical approach for managing soil loss and understanding the importance of selecting appropriate site-specific BMPs.

With the advent of national storm water regulations, municipalities with populations greater than 100,000 are required to obtain National Pollutant Discharge Elimination System Permits (NPDES) for storm water discharges. In addition to the sampling required for the permit process, the City of Fort Worth contracted with the University of North Texas' Institute of Applied Sciences to conduct acute toxicity testing using Pimephales prcmelas and Ceriodaphnia dubia on storm water samples received from the Dallas/Fort Worth Metroplex. A Toxicity Identification Evaluation (TIE) was performed on four samples that exhibited acute toxicity to C. dubia. High levels of metals as well as diazinon were some of the probable toxicants found.

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Med ett förändrat klimat förväntas nederbörd och kraftiga skyfall öka i framtiden. Detta i kombination med en ökad urbanisering och allt fler hårdgjorda ytor i städerna leder till att befintliga dagvattensystem kommer bli överbelastade. Nederbörden förväntas öka med 10-20 procent och avrinningen med 5-25 procent under det närmaste seklet. I många städer har de naturliga avrinningsområdena försvunnit i samband med urbaniseringen och bostäder byggs på olämpliga platser med stor översvämningsrisk. Behovet av en hållbar dagvattenhantering är betydande för att undvika negativa konsekvenser i städerna framöver. Den traditionella dagvattenhantering med rörsystem blir alltmer kritiserad för att vara ohållbar. I Malmö är dagvattenfrågan högst aktuell då staden nyligen blivit drabbad av översvämningar. Studiens fokus ligger på vilken syn större fastighetsägare och VA-huvudmannen har på dagvattenhantering i ett förändrat klimat. Studien är av både kvalitativ och kvantitativ karaktär och består av två intervjuer samt en kompletterande enkätundersökning. De slutsatser som framkommit av studien är följande: Det behövs ett ökat samarbete med skyfallsproblematiken i Malmö, förändring av lagstiftningen för tydligare ansvarsförhållanden, fastställa finansieringen av åtgärder, arbeta mer mot öppna lösningar och minska fokus på ledningsnätet, öka kunskapen hos stadsplanerare och fastighetsägare, lyfta dagvattenfrågan tidigt i planprocessen samt våga arbeta mot en långsiktigt hållbar stadsplanering som inte fokuserar på kortsiktiga vinstintressen. / As a result of the changing climate precipitation and intensified rainfalls is expected to increase. This combined with an increased urbanisation and more of hard surfaces in cities causes greater pressure on exsisting storm water systems. The precipitation over Sweden is expected to increase with 10-20 percent and the run-off with 5-25 percent over the next century. Due to the urbanisation the natural drainage areas have disappeared and areas with high flood risk have been exploitated. To avoid negative consequenses in the future, sustainable storm water management is needed. Conventional storm water systems is more and more criticized of being unsustainable. The storm water issue is a highly disscused topic in Malmö as the city flooded during 2014. The focus of the study is property owner and the public water suppliers view on storm water management in a changing climate. The study uses both quantitative and qualitative methods and consists of two interviews and a supplementary questionnaire. The study’s conclusions are as followed: the need for increased cooperation with torrential rain problems in Malmö, change in legislation in terms of clarify responsibilities, determine the financing of measures, work more towards open solutions and reduce the focus on pipe-based storm water system, increase knowledge among city planners and property owners, bring up the stormwater issue early in the planning process and a determenation to work towards long-term sustainable planning rather than focusing on short- term profits.

The EU's Water Framework Directive aims to a long-term and sustainable use of our water resources and wants to ensure good water quality in Europe's water bodies. Discharge of polluted stormwater into receiving waters can be a threat to their ecological and chemical status. Municipalities are responsible for supervision of the environmental quality standards (EQS) and therefore need to gain knowledge of current stormwater management, the expected level of pollution emissions and possible appropriate purification steps to ensure that the goal of good water quality is achieved. This master thesis aims to provide this knowledge in the example case of Vallentunas urban area and wants to prepare future oversight so that it can be assessed how much the discharge of polluted stormwater into the local receiving water is a threat to its status. With the help of maps, aerial photographs, site observations and individual discussions those areas are mapped where appearance of moderate to highly polluted stormwater could be suspected. The degree of pollution at the discharge points is determined based on land use upstream and uses standard values according to the administrators assistance "Tillsyn av dagvatten" (MSL 2014). The study identifies 100 areas in need of supervision regarding their stormwater management. The information is digitized and made available to all affected departments in the municipality via the internal GIS. Through literature review this thesis highlights even the legal provisions for the supervision and its importance to the environmental quality standards and also consider the importance of the expected climate change for the stormwater pollution. The work emphasizes the importance of increased information flow and communication between the different actors that are significant for surface water management and environmental quality standards for water. For being able to look at the examination area from an international perspective the essay does a simpler comparison of the municipal supervision of stormwater management between Sweden and the state of Schleswig Holstein in Germany. / EU:s ramdirektiv för vatten syftar till ett långsiktigt och hållbart utnyttjande av våra vattenresurser och ska säkra en god vattenkvalitet i Europas vattenförekomster. Utsläpp av förorenat dagvatten till recipienterna kan vara ett hot för deras ekologiska och kemiska status. Kommunerna har tillsynsansvar för miljökvalitetsnormerna (MKN) och därför behov att få kunskap om nuvarande dagvattenhantering, förväntad föroreningsgrad av utsläppen och eventuella lämpliga reningsåtgärder för att säkerställa att målet med en god vattenkvalitet uppnås. Arbetets syfte är att hjälpa till att skaffa denna kunskap i exempelfallet Vallentuna tätort och förbereda framtida tillsyn så att det kan göras en bedömning av hur pass mycket utsläppet av förorenat dagvatten till den lokala recipienten är ett hot för dess status. Med hjälp av kartor, flygbilder, platsobservationer och enskilda samtal kartläggs områden där man kan förvänta sig uppkomsten av måttligt till starkt förorenat dagvatten. Föroreningsgraden vid utsläppspunkterna bestäms utifrån markanvändning uppströms och använder schablonvärden enligt handläggarstödet "Tillsyn av dagvatten" (MSL 2014). Undersökningen pekar ut 100 områden som har behov av tillsyn rörande deras dagvattenhantering. Informationen digitaliseras och görs tillgänglig för alla berörda enheter i kommunen via det interna GIS-systemet. Genom granskning av litteraturen belyses bl.a. även de rättsliga bestämmelserna för tillsynen och dess betydelse för miljökvalitetsnormerna samt att det tas hänsyn till förväntad klimatförändring. Arbetet betonar vikten av ett ökat informationsflöde och kommunikation mellan de olika aktörerna som har betydelse för dagvattenhanteringen och miljökvalitetsnormerna för vatten. För att se på uppsatsens undersökningsområde ur ett internationellt perspektiv görs även en enklare jämförelse av tillsynen för dagvattenhanteringen mellan Sverige och förbundslandet Schleswig Holstein i Tyskland.