Understanding the nature of streamflow response to precipitation inputs is at the core of applied hydrological applications such as flood forecasting and water resource management. Indices such as the runoff ratio, recession constant and response time of a watershed retain an important place in hydrology decades after their establishment as metrics to compare watersheds and understand the impact of human activity, geology, geomorphology, soils and climate on precipitation-runoff relations. Extracting characteristics of the hyetograph-hydrograph relationship is often done manually, resulting in subjective and inconsistent results that require considerable time. In addition, there are a large number of metrics proposed to analyze the hyetograph-hydrograph relationship and hydrograph shape that are typically subjective in application. The objective of this research is to develop an automated and flexible toolkit for rainfall-runoff analysis. Using the MATLAB language, a series of inter-related functions are created to extract rainfall-runoff events from time-series of rainfall and streamflow data and compute commonly used characteristics of the hyetograph-hydrograph relationship. Furthermore, a number of input parameters are introduced to add flexibility to the toolkit. This toolkit has been applied successfully to four watersheds in Canada and Scotland. A subsequent analysis was performed assessing the sensitivity of parameter selection on the toolkit performance, and a number of suggestions for users provided. It is anticipated that this toolkit will provide hydrologists with a rapid objective method of analyzing rainfall and runoff data where in the past manual procedures resulted in considerable subjectivity in results. / Thesis / Master of Science (MSc)

Os custos econômicos e perdas potenciais de vidas humanas resultantes de falhas em sistemas de drenagem de águas pluviais podem ser enormes, aumentando a necessidade da busca de melhores métodos de dimensionamento destes. Os métodos baseados na precipitação de projeto são os mais usados para a estimativa do hidrograma de projeto em bacias urbanas, devido às facilidades que os mesmos apresentam em relação aos outros métodos. Entretanto, estes métodos têm suas limitações e incertezas, que podem influenciar as características do hidrograma de projeto resultante, incertezas que são, em consequência, transferidas ao dimensionamento hidráulico das obras propostas. No presente trabalho, foram avaliados os efeitos da discretização espacial da bacia, da discretização temporal e da posição do pico do hietograma de projeto, sobre as principais características do hidrograma de projeto. Esses efeitos foram ainda avaliados no dimensionamento hidráulico do sistema de macrodrenagem dos bairros de Mavalane “A” e Maxaquene “A”, localizados na cidade de Maputo em Moçambique. Para avaliar os referidos efeitos, a bacia foi discretizada em 1, 5, 7 e 12 sub-bacias. O intervalo de tempo do hietograma de projeto foi discretizado em 1, 2, 3, 4 e 5 minutos, sendo calculados para cada discretização e intervalo de tempo, hietogramas com pico no início, 25%, 50%, 75% e final do evento com duração correspondente a 90 minutos e 24 horas. Os hietogramas foram transformados em vazão no programa IPHS1, a qual foi propagada no sistema de macrodrenagem usando o modelo EPA SWMM 5.0, sendo obtidos os hidrogramas de projeto resultantes. O exutório da bacia e o trecho C19 localizado na região central da bacia foram escolhidos para análise dos resultados. Os resultados obtidos mostram uma influência importante dos efeitos avaliados nas características do hidrograma de projeto: vazão de pico, tempo de pico e volume parcial e, consequentemente, no dimensionamento da rede de macrodrenagem, sendo o efeito da discretização da bacia o mais influente, seguido dos efeitos da posição do pico da chuva e intervalo de tempo. / The economic costs and potential losses of human lives due to failure in stormwater drainage systems can be significant, calling for an improvement in methods used for its design. The design storm approach, also known as “single-event design-storm” is widespread used in formulating design hydrograph from historical rainfall data in urban watersheds, due to its relative advantages when compared to other methods. Therefore, this approach has its uncertainties which can affect the resulted design hydrograph, and consequently affect the hydraulic design of proposed structures. In this study is presented an assessment of the adopted values in design criteria, during the estimation of design hydrograph used in hydraulic design of stormwater drainage systems. In particular, are assessed the effects of spatial discretization of the watershed, the temporal discretization and peak position of the design hyetograph, in the main features of the resulted design hydrograph. The same effects are then assessed in the hydraulic design of the major stormwater drainage system of Mavalane “A” and Maxaquene “A” neighborhoods, located in Maputo city in Mozambique. To assess these effects, the watershed was discretized into 1, 5, 7 and 12 sub-watersheds. The time step of the design hyetograph was discretized into 1, 2, 3, 4 and 5 minutes, and then computed for each discretization and time step, hyetographs with peak positioned in the beginning, 25%, 50%, 75% and the end of the duration of 90 minutes and 24 hours. The hyetographs were converted into runoff in IPHS1, wish was dynamically routed in the drainage system, using EPA SWMM 5.0. The watershed outlet and conduit C19 were used to analyze the results. The results show an important influence of the assessed effects on the design hydrograph features: hydrograph peak, time to peak and partial volume and, consequently, on the hydraulic design of the major stormwater drainage system, being the effect of spatial discretization of the watershed, the most important, followed by hyetograph peak position and time step.

Os custos econômicos e perdas potenciais de vidas humanas resultantes de falhas em sistemas de drenagem de águas pluviais podem ser enormes, aumentando a necessidade da busca de melhores métodos de dimensionamento destes. Os métodos baseados na precipitação de projeto são os mais usados para a estimativa do hidrograma de projeto em bacias urbanas, devido às facilidades que os mesmos apresentam em relação aos outros métodos. Entretanto, estes métodos têm suas limitações e incertezas, que podem influenciar as características do hidrograma de projeto resultante, incertezas que são, em consequência, transferidas ao dimensionamento hidráulico das obras propostas. No presente trabalho, foram avaliados os efeitos da discretização espacial da bacia, da discretização temporal e da posição do pico do hietograma de projeto, sobre as principais características do hidrograma de projeto. Esses efeitos foram ainda avaliados no dimensionamento hidráulico do sistema de macrodrenagem dos bairros de Mavalane “A” e Maxaquene “A”, localizados na cidade de Maputo em Moçambique. Para avaliar os referidos efeitos, a bacia foi discretizada em 1, 5, 7 e 12 sub-bacias. O intervalo de tempo do hietograma de projeto foi discretizado em 1, 2, 3, 4 e 5 minutos, sendo calculados para cada discretização e intervalo de tempo, hietogramas com pico no início, 25%, 50%, 75% e final do evento com duração correspondente a 90 minutos e 24 horas. Os hietogramas foram transformados em vazão no programa IPHS1, a qual foi propagada no sistema de macrodrenagem usando o modelo EPA SWMM 5.0, sendo obtidos os hidrogramas de projeto resultantes. O exutório da bacia e o trecho C19 localizado na região central da bacia foram escolhidos para análise dos resultados. Os resultados obtidos mostram uma influência importante dos efeitos avaliados nas características do hidrograma de projeto: vazão de pico, tempo de pico e volume parcial e, consequentemente, no dimensionamento da rede de macrodrenagem, sendo o efeito da discretização da bacia o mais influente, seguido dos efeitos da posição do pico da chuva e intervalo de tempo. / The economic costs and potential losses of human lives due to failure in stormwater drainage systems can be significant, calling for an improvement in methods used for its design. The design storm approach, also known as “single-event design-storm” is widespread used in formulating design hydrograph from historical rainfall data in urban watersheds, due to its relative advantages when compared to other methods. Therefore, this approach has its uncertainties which can affect the resulted design hydrograph, and consequently affect the hydraulic design of proposed structures. In this study is presented an assessment of the adopted values in design criteria, during the estimation of design hydrograph used in hydraulic design of stormwater drainage systems. In particular, are assessed the effects of spatial discretization of the watershed, the temporal discretization and peak position of the design hyetograph, in the main features of the resulted design hydrograph. The same effects are then assessed in the hydraulic design of the major stormwater drainage system of Mavalane “A” and Maxaquene “A” neighborhoods, located in Maputo city in Mozambique. To assess these effects, the watershed was discretized into 1, 5, 7 and 12 sub-watersheds. The time step of the design hyetograph was discretized into 1, 2, 3, 4 and 5 minutes, and then computed for each discretization and time step, hyetographs with peak positioned in the beginning, 25%, 50%, 75% and the end of the duration of 90 minutes and 24 hours. The hyetographs were converted into runoff in IPHS1, wish was dynamically routed in the drainage system, using EPA SWMM 5.0. The watershed outlet and conduit C19 were used to analyze the results. The results show an important influence of the assessed effects on the design hydrograph features: hydrograph peak, time to peak and partial volume and, consequently, on the hydraulic design of the major stormwater drainage system, being the effect of spatial discretization of the watershed, the most important, followed by hyetograph peak position and time step.

Os custos econômicos e perdas potenciais de vidas humanas resultantes de falhas em sistemas de drenagem de águas pluviais podem ser enormes, aumentando a necessidade da busca de melhores métodos de dimensionamento destes. Os métodos baseados na precipitação de projeto são os mais usados para a estimativa do hidrograma de projeto em bacias urbanas, devido às facilidades que os mesmos apresentam em relação aos outros métodos. Entretanto, estes métodos têm suas limitações e incertezas, que podem influenciar as características do hidrograma de projeto resultante, incertezas que são, em consequência, transferidas ao dimensionamento hidráulico das obras propostas. No presente trabalho, foram avaliados os efeitos da discretização espacial da bacia, da discretização temporal e da posição do pico do hietograma de projeto, sobre as principais características do hidrograma de projeto. Esses efeitos foram ainda avaliados no dimensionamento hidráulico do sistema de macrodrenagem dos bairros de Mavalane “A” e Maxaquene “A”, localizados na cidade de Maputo em Moçambique. Para avaliar os referidos efeitos, a bacia foi discretizada em 1, 5, 7 e 12 sub-bacias. O intervalo de tempo do hietograma de projeto foi discretizado em 1, 2, 3, 4 e 5 minutos, sendo calculados para cada discretização e intervalo de tempo, hietogramas com pico no início, 25%, 50%, 75% e final do evento com duração correspondente a 90 minutos e 24 horas. Os hietogramas foram transformados em vazão no programa IPHS1, a qual foi propagada no sistema de macrodrenagem usando o modelo EPA SWMM 5.0, sendo obtidos os hidrogramas de projeto resultantes. O exutório da bacia e o trecho C19 localizado na região central da bacia foram escolhidos para análise dos resultados. Os resultados obtidos mostram uma influência importante dos efeitos avaliados nas características do hidrograma de projeto: vazão de pico, tempo de pico e volume parcial e, consequentemente, no dimensionamento da rede de macrodrenagem, sendo o efeito da discretização da bacia o mais influente, seguido dos efeitos da posição do pico da chuva e intervalo de tempo. / The economic costs and potential losses of human lives due to failure in stormwater drainage systems can be significant, calling for an improvement in methods used for its design. The design storm approach, also known as “single-event design-storm” is widespread used in formulating design hydrograph from historical rainfall data in urban watersheds, due to its relative advantages when compared to other methods. Therefore, this approach has its uncertainties which can affect the resulted design hydrograph, and consequently affect the hydraulic design of proposed structures. In this study is presented an assessment of the adopted values in design criteria, during the estimation of design hydrograph used in hydraulic design of stormwater drainage systems. In particular, are assessed the effects of spatial discretization of the watershed, the temporal discretization and peak position of the design hyetograph, in the main features of the resulted design hydrograph. The same effects are then assessed in the hydraulic design of the major stormwater drainage system of Mavalane “A” and Maxaquene “A” neighborhoods, located in Maputo city in Mozambique. To assess these effects, the watershed was discretized into 1, 5, 7 and 12 sub-watersheds. The time step of the design hyetograph was discretized into 1, 2, 3, 4 and 5 minutes, and then computed for each discretization and time step, hyetographs with peak positioned in the beginning, 25%, 50%, 75% and the end of the duration of 90 minutes and 24 hours. The hyetographs were converted into runoff in IPHS1, wish was dynamically routed in the drainage system, using EPA SWMM 5.0. The watershed outlet and conduit C19 were used to analyze the results. The results show an important influence of the assessed effects on the design hydrograph features: hydrograph peak, time to peak and partial volume and, consequently, on the hydraulic design of the major stormwater drainage system, being the effect of spatial discretization of the watershed, the most important, followed by hyetograph peak position and time step.

This report deals with rainfall-runoff modeling and small water reservoir projection with usage of modern software equipments (GIS, HEC-HMS), using maximum number of available data sources (BPEJ, LPIS, N-year rainfall gages, 3D contours …). The advantage of this method is that it is possible to predict the shape of hydrograph and flood wave volume as well. Other methods cannot offer judgment of flood wave volume and hydrograph shape as this method does. The most important thing in small water reservoir projection is the flood wave volume value, which is undervalued nowadays using wrong evaluation. This method’s advantage is variability of scenarios depending on soil surface, used agricultures, hydraulic and hydrologic parameters etc.

Pluvial floods are the most difficult and to date least investigated phenomena in urban hydrology. While efforts are being made to increase the knowledge base concerning this type of flooding, a large part of the difficulty lies in the nature of the precipitation. Convective storms represent most of the larger intensity short term rainfall in urban areas and is also the raintype, that is expected to increase the most in the future. The rain cells of this type have a more distinct boundary, larger intensity, a smaller extent and a shorter life span, than frontal rains. Combined with the low availability of densely spaced rain gauge networks and also low temporal resolution of measurements in 15 minutes intervals at best, makes this rain type still very difficult to analyze and even harder to predict. The resolution of cloud radar images at 2x2km and taken every 15 minutes is too coarse and the error reduction algorithms for radar based precipitation (HIPRAD) images to analysera in patterns are not sufficient by them selves to analyze the characteristics of such rainfields and the processes occurring within these fields. The spatial variation of raincells, their development and decay, the distance between them, and the velocity and direction of their movement can however be investigated employing a combination of densely spaced rain gauges and radar images to reach a more realistic representation of short-term precipitation for the use of in hydraulic models. The movement of rain fields has been investigated with two main areas of focus: The influence of direction or directional bias, often with an interest in the most crucial case referred to as the resonance effect, and in context of areal reduction of point rainfall. Most of these studies have been carried out with statistical methods and in laboratory experiments. In this study a hydraulic model was built on the terrain model of a realcity, a 28 km area in the city of Falun, to test the recently gathered information about the temporal variation of five empirical hyetographs with different peak arrival times and peak intensities, which are representative of Swedish climate. The hyetographs were produced and provided by SMHI. The empirical rain types were derived from 20 years of rain gauge observations and confirmed by radar images. For reference purposes, a standard Chicago design storm (CDS) rain was modeled as well. The simulated scenarios were modeled as a MIKE 21 hydraulic model, as a stationary scenario and in four movement directions. It was foundthat the empirical rain types produced lower inundation depth than the CDS, in a range of 20 to 50 % lower. The effect of modeling rainfall in motion produced on average only about 4-20 % lower water depths than the corresponding non-moving scenario. In a few instances, in a single evaluation point, the moving scenarios resulted in a relative water depth of a maximum of just above 1%. It was concluded that the conceptual approach of areal reduction from movement seems to be accurate and could help improve modeling rainfall in general, and specifically for cloud burst scenarios of shorter durations in urban catchments. It was also found that further investigation of the physical processes in rainfields could serve to increase the accuracy in areal reduction of precipitation for more realistic hydraulic models and in turn reduce over design. / Pluviala översvämningar är den typen, som är både svårast att reda ut och samtidigt den minst utforskade fenomenen inom urban hydrologi. Medan ansträngningar görs för att förbättra kunskapsläget, ligger den största svårigheten i nederbördens skepnad. Det är konvektiva regn som utgör de flesta av de starkare korttids regntillfällen i urbana områden och är också regntypen som förväntas att öka mest i framtiden. Regncellerna har en tydligare avgränsning, en större intensitet, mindre utsträckning, och en kortare livscykel än frontala regn. I kombination med den låga tillgängligheten av regnmätarnätverk med hög täthet i positioneringen av mätare, samt den låga tidsupplösningen av mätningar i intervaller av 15 minuter gör att konvektiva regn fortfarande är svåra att analysera och ännu svårare att förutse. Upplösningen av molnradar bilder av 2x2 km som tas varje 15:de minut är för grova och algoritmer för felreducering av bilder från radarbaserad nederbördsdata (HIPRAD) för analys av regn mönster är inte tillräckligt noggranna, för sig, för att kunna analysera egenskaperna av sådana regnfält och de processerna som karakteriserar dessa. Den spatiala variationen inom regnceller, deras utveckling och förfall, avståndet mellan dem samt riktningen och hastigheten kan ändå undersökas med hjälp av kombinationen av regnmätarnätverk och radar bilder för att uppnå mer realistiska korttids nederbördsscenarier för användning i hydrauliska model. Studier, som har undersökt regn i rörelse har varit fokuserade på två huvudområden: Betydelsen av riktningen, i vilken regnet rör sig, där den största effekten som denna riktningsbias kan uppnå, har döpts resonans effekt och i samband med ytreducering (areal reduction) av punkt nederbörd. De flesta av dessa studier har genomförts med hjälp av statistiska metoder och laboratorieexperiment. I denna studie skapades en hydraulisk modell baserad på en realistisk terräng av ett existerade urbant område, en yta på 28 km i Falun, för att testa den nyligen utvärderade informationen om temporala intensitets fördelningen som representerar det svenska klimatet. Regndatat producerades och tillhandahölls av SMHI och representerar en mätserie från regnmätare över en period av 20 år. Som referens modellerades även ett Chicago regn (CDS). Med hjälp av en MIKE21 hydraulisk modell, simulerades ett stationärt scenario och fyra rörelseriktningar för varje empirisk hyetograf. Resultaten visade att de empiriska regntyperna skapade översvämningar med 20-50% lägre vattendjup än CDS regnet. Att modellera rörelsen resulterade i 4-20% lägre vattennivåer jämfört med respektive stationär scenario. I några enstaka tillfällen, i en av evalueringspunkterna, skapade de rörliga scenarierna större resultat, med lite över 1% i det största fallet. Det drogs slutsatsen att konceptet av areal reduction genom molnrörelse verkar vara korrekt och skulle kunna hjälpa att förbättra sättet att modellera regn generellt, men också specifikt för skyfalls scenarier med korta varaktigheter över urbana avrinningsområden. Man kom ytterligare till slutsatsen att framtida studier i samband med de fysiska processerna i regnceller skulle kunna användas för att höja noggrannheten av ytreducering av nederbörd för mer realistiska hydrauliska modeller, som i sin tur kunde minska överdesign.

The field of urban hydrology is in need of high temporal resolution data series in order to effectively model and analyse existing and future trends in extreme precipitation. When high resolution data sets are, for any number of reasons, not available for a given location, the technique of disaggregation using a random cascade model can be applied. Previous studies have demonstrated the relevance of random cascades in the context of rainfall data disaggregation with temporal resolutions usually down to 1 hour. In this study, an attempt at disaggregation to a resolution of 1 minute was made. Using newly disaggregated rainfall data for different regions in Sweden, the possibility of clustering rain events into separate regional hyetographs was investigated. The random cascade model was calibrated using existing municipal rainfall data with a temporal resolution of 1 minute, in order to disaggregate continuous 15 minutes data series provided by the Swedish Meteorological and Hydrological Institute (SMHI). The disaggregation process was then performed in multiple stochastic realisations, in order to correct the uncertainties inherent to the random cascade model. The disaggregation results were assessed by comparing them with calibration data: two main rainfall parameters, EV and ED, were analysed by determining their behaviours and distribution. The possibility of transfering calibration parameters from one station to another was also assessed in a similar manner, again by studying EV & ED for different scenarios. Finally, hyetographs were clustered, compared and contrasted, in order to ascertain previously theorized differences between regions. This research showed the feasibility of applying a random cascade model to very high temporal resolutions in Sweden, while replicating rainfall characteristics from the calibration data quite well. The analysis of the spatial transferability of calibration parameters yielded inconclusive results, as rainfall characteristics were preserved in some cases but failed in others. Lastly, distinct regional differences in hyetographs were noted, but no clear conclusions could be drawn owing to the delimitations of this study. / Inom småskalig hydrologisk modellering finns det idag ett behov av dataserier med hög tidsupplösning för att effektivt kunna modellera och analysera både aktuella och kommande trender hos extrema regnhändelser. När högupplösta dataserier är otillgängliga vid en önskad mätplats kan disaggregering med hjälp av en slumpmässig kaskadmodell tillämpas. Tidigare forskning har visat att kaskadmodeller är användbara för disaggregering av regndata med en tidsupplösning av 1 timme. I denna studie disaggregerades dataserier med syftet att uppnå en tidsupplösningav av 1 minut. För att kunna analysera eventuella skillnader mellan regioner klustrades även hyetografer med de framtagna dataserierna. Den slumpmässiga kaskadmodellen kalibrerades med befintlig kommunal data med en tidsupplösning på 1 minut, för att sedan kunna disaggregera 15 minuters data från SMHIs databaser. Disaggregeringen genomfördes i ett antal olika stokastiska realisationer för att kunna ta hänsyn till, och korrigera, de inneboende osäkerheterna i den slumpmässiga kaskadmodellen. Disaggregeringsresultaten bedömdes genom en jämförelse med kalibreringsdata: två regnegenskaper, regnvaraktighet (ED) och regnvolym (EV), analyserades för att kunna bestämma derasfördelningar och beteenden. Kalibreringsparametrarnas överförbarhet analyserades också med hjälp av ED & EV för olika scenarier. Slutligen klustrades hyetografer för att fastställa potentiella skillnader mellan regioner. Studien påvisade möjligheten att använda en slumpmässig kaskadmodell till höga tidsupplösningar i Sverige. Modellen lyckades återskapa regnegenskaper från kalibreringsdata vid disaggregeringen. Möjligheten att överföra kalibreringsparametrar från en station till en annan visade sig dock inte vara helt övertygande: regnegenskaper återskapades endast i vissa fall, men inte i samtliga. Slutligen konstaterades regionala skillnader i hyetografer, men tydliga slutsatser kunde inte dras på grund av underliggande begränsningar med studien.

Pluvial floods are formed directly from surface runoff after extreme rain events. Urban areas are prone to suffer from these floods due to large portions of hardened surfaces and limited capacity in the stormwater infrastructure. Previous research has shown that catchment response is influenced by the spatio-temporal behaviour of the rainstorm. A rainstorm moving in the same direction as the surface flow can amplify the runoff peak and temporal variability of rainfall intensity generally results in greater peak discharge compared to constant rainfall. This research attempted to relate the effect of storm movement on flood propagation in urban pluvial flooding to the effect from different distributions of rainfall intensity. An additional objective was to investigate the flood response from recent findings on the temporal variability in Swedish rain events and compare it to the flood depths produced by a CDS-rain (Chicago Design Storm), where the latter is the design practice in flood modelling today. A 2D surface model of an urban catchment was coupled with a 1D model of the drainage network and forced by six different hyetographs. Among them were five empirical hyetographs developed by Olsson et al. (2017) and one a CDS-rain. The rainstorms were simulated to move in different directions: along and against the surface flow direction, perpendicular to it and with no movement. Maximum flood depth was evaluated at ten locations and the model results show that storm movement had negligible effect on the flood depths. The impact from the movement was likely limited by the big difference in speed between the rainstorm and the surface flow. All evaluated locations showed a considerable sensitivity to changes in the hyetograph. The maximum flood depth increased at most with a factor of 1.9 depending on the hyetograph that was used as model input. The CDS-rain produced higher flood depths compared to the empirical hyetographs, although one of the empirical hyetographs produced a similar result. Based on the results from this case study, it was concluded that storm movement was not as critical as the temporal variability of rainfall when evaluating maximum flood depth. / Pluviala översvämningar skapas från ytavrinning vid intensiva nederbördstillfällen. De uppstår ofta i urbana miljöer till följd av den höga andelen hårdgjorda ytor och ledningsnätets begränsade kapacitet. Forskning har visat att ett regnmolns rörelseriktning och hastighet påverkar avrinningsförloppet. Om molnet rör sig längs med flödesriktningen i terrängen kan en ökning i vattenlödet nedströms ett avrinningsområde uppstå. Denna effekt har visat sig vara störst om hastigheten hos regnmolnet och vattenflödet är likvärdiga. Ytterliggare en faktor som påverkar avrinningsförloppet är hur regnintensiteten är fördelad över tid. Olsson et al. (2017) har tagit fram fem empiriska regntyper som speglar tidsfördelning inom ett Svenskt regntillfälle. Inom översvämningsmodellering är det vanligt att använda ett så kallat CDS-regn (Chicago Design Storm), vilken har en given tidsfördelning. Med anledning av detta är det intressant att jämföra översvämningar genererade av ett CDS-regn och av de empiriska regntyperna. Syftet med denna studie var att utreda hur regnmolns rörelse påverkar urbana pluviala översvämningar med avseende på vattendjup, samt att jämföra denna påverkan med effekten från olika tidsfördelningar av regnintensiteter. En kombinerad dagvattenmodell (1D) och markavrinningsmodell (2D) av en mindre svensk tätort användes för att simulera olika regnscenarier. De fem empiriska regntyperna och ett CDS-regn simulerades med en rörelseriktning längs med, emot och vinkelrätt i förhållande till flödesriktningen. Även scenarier med stationära regnmoln simulerades. Maximala översvämningsdjup utvärderades i tio punkter spridda över hela modellområdet. Resultatet från simuleringarna visade att regnmolnets rörelse hade försumbar påverkan på översvämningsdjupen. De olika tidsfördelningarna av regnintensitet hade däremot betydande påverkan på de maximala översvämningsdjupen. Som mest var det det maximala översvämningsdjupet 1.9 gånger större beroende vilken regntyp som användes som indata. CDS-regnet genererade i regel de största översvämningsdjupen, även om utfallet från en av de fem empiriska regntyperna var förhållandevis likvärdigt. Regnintensitetens tidsfördelning var därmed en kritisk parameter vid den hydrauliska modelleringen av urbana pluviala översävmningar, till skillnad från molnrörelse som hade försumbar påverkan.