The studies in this dissertation address the issue of variability in runoff generation and pollutant concentration in urban areas, and specifically in the catchments of stormwater control measures. There is an imperfect correlation between runoff volumes and the capture area and land uses of urban catchments. Variable capture areas and uncertainty in urban runoff sources complicate stormwater control measure design and urban stream assessment. Four stormwater control measures in upstream suburban Philadelphia, ranging in capture area from 0.11 ha to 32 ha, were monitored, sampled, and modeled. Sampling was conducted in the watersheds of Wissahickon Creek, Tookany Creek, and Pennypack Creek. The approaches discussed below have the goal of better understanding runoff and the movement of associated contaminants into stormwater retention basins and streams. Rather than viewing runoff generation and contaminant transport as a static process, this work proposes that the amount of runoff contributed from different areas of a catchment changes during and between storm events, and that the origin and concentration of contaminants change as a result. Linking source areas to runoff volumes through natural and modeled tracers could improve predictions of water quality and quantity in stormwater control measures in urban streams. Nitrate (NO3–) isotope ratios were used as tracer of flow from different urban land uses. Time series samples of stormwater runoff entering two stormwater control measures (a constructed wetland and a small bioretention basin) were collected and analyzed to distinguish sources of NO3– by samples’ δ15N and δ18O ratios. A Bayesian mixing model was used to determine that NO3– sources were a mix of soil nitrogen (N) and atmospheric deposition across six storm events. Furthermore, atmospheric versus soil N sources varied throughout the storms. The large catchment of the constructed wetland had more NO3– source variability between samples compared to the small catchment of the bioretention basin. Thus, the NO3– isotopes suggest more distinct flow paths in the large catchment and more mixing of flow across land uses in the small catchment. Quantifying flow path variability from storm to storm and between different catchments can improve design and placement of urban stormwater control measures. A distributed hydrologic model, GSSHA, was used to simulate overland runoff from impervious and semi-pervious land covers in the catchment of a stormwater control measure. The positions of low vegetation and impervious land uses over the catchment were rearranged to create hypothetical catchments during four storm events. Fluctuating source proportions over time suggested that grab samples might not be adequate for capturing average overland runoff chemistry. It was also found that the portion of total runoff volume from impervious areas varied from 50 to 75% while the relative proportion of impervious cover remained constant at 54%. Land use percentages averaged over capture areas are frequently used to estimate runoff amounts and pollutant concentrations, but this model disrupts the assumption that urban hydrologic responses can be predicted from imperviousness alone. Overland runoff was measured and modeled before and after the installation of two stormwater control measures, a berm and a bioswale. Discharge in the stream was modeled for 9 storms ranging in size from 14 to 54 mm. We found that during 4 of the modeled storms there was no decrease in stream discharge and decreases in discharge were generally only observed for low intensity storms. Furthermore, only 5% of the stream catchment was captured by SCMs. Modeled tracers, used to track runoff contributions from areas upslope of the SCMs found that the size of upslope contributing areas did not predict the proportion of runoff generated in each area. Field data to support the models included water level loggers and samples of overland runoff collected in subsurface stormwater casing. After the SCMs were installed, less water was captured in downslope sampling bottles, but new flow paths developed. Furthermore, significant variation was observed in upslope concentrations of dissolved nutrients and total suspended solids, casting doubt on whether point samples of urban overland runoff geochemistry can be representative given variable runoff generation and heterogeneous land uses. This study points out the challenges in evaluating stormwater control measures and reveals that source areas’ contribution to stream flow varies independently of their size. Therefore, modeling before stormwater control measure installation is recommended to determine the factors that influence a capture area’s contribution to urban streamflow. / Geoscience

En France, face aux problèmes liés au réseau d’assainissement hérité du XIXème siècle, une solution consiste à gérer les eaux pluviales par des techniques « alternatives » au réseau. Le « tout tuyau » fait place à un ensemble d’objets techniques hybrides, composés d’éléments naturels et de matériaux synthétisés. Ces « objets de nature » présentent une apparence mixte (naturelle/artificielle) et assurent des fonctions multiples qui peuvent rendre leur intégration difficile. Dans quelles mesures l’appropriation des objets de nature par les publics est-elle difficile? Comment s’établit la place des objets de nature dans la ville? Cette thèse vise plusieurs objectifs. Il s’agit de renseigner les relations entre publics et objets de nature, d’obtenir des éléments sur les pratiques et usages des publics et d’apporter une réflexion sur la manière d’étudier les comportements humains. Pour se faire, trois enquêtes basées sur de l’observation directe doublée par une prise d’images systématisée ont été menées au cours de quatre saisons et à travers 12 études de cas réparties au sein de la métropole lyonnaise. Ces enquêtes ont tout d’abord permis de préciser la construction de l’objet de nature en tant qu’instrument à travers le concept de genèse instrumentale de Rabardel. Ensuite, les pratiques, usages ainsi que les conditions d’utilisation des dispositifs ont pu être définis grâce aux comportements observés chez les publics. Enfin, les avantages et limites de l’observation directe et des conditions d’analyse des données ont été discutés dans le but d’apporter des pistes d’amélioration à cette méthodologie pour de futures études. / To better manage storm water and to respond to problems related to the sanitation networks conceived in the 19th Century, some alternative techniques, other than networks, are being put forward. The “all tubes” concept is giving way to various technical objects of a hybrid nature made up of natural components and synthesized material. The physical appearance of these “natural objects” is double (both natural and artificial) and they fulfil various purposes. Thus, their insertion in the landscape can be delicate. How are these natural objects seized by society? In this process are any difficulties encountered? How is the place for natural objects defined in a city? The purpose of this dissertation is triple: (1) gather information on the relationship between societies and natural objects, (2) collect data on the public's use and practices, (3) discuss a methodology to study human behavior. Three inquiries were carried out during the four seasons of the year and in twelve sites; they were based on direct observation and systematized photography. Based on the fieldwork and the concept of “genèse instrumentale” developed by Rabardel, a discussion was developed on the building of a natural object as a tool. Subsequently, based on the observation of the public, practices, uses and the conditions in which these natural objects are used were defined. The dissertation concludes by highlighting the advantages and the limits of direct observation, and by developing the biases such as the context in which the data was analyzed, in order to suggest some possible methodological enhancements which could help future studies.

Des approches parcimonieuses sont aujourd'hui développées pour la modélisation de la qualité des rejets urbains par temps de pluie, e adéquation avec la quantité de données disponibles. De plus, l'analyse des incertitudes apparaît comme un outil incontournable pour le test des modèles. Parallèlement, le développement des techniques de mesure en continu en réseau, spectrométrie et turbidité, permet l'obtention de données continues de flux de matières en suspension et de demande chimique en oxygène en grand nombre, apportant une information riche. Ce travail constitue une des premières études en hydrologie urbaine basée sur l'exploitation d'une grande base de données acquises par la mesure de la turbidité. Des mesures sur la période 2004-2008 ont été exploitées sur deux sites. Après traitement et validation, 263 et 239 événements pluvieux ont été retenus. L'analyse des données a permis la formulation d'hypothèses sur la génération des flux pour la proposition de modèles adaptés. Le test de l'approche multi-régression a confirmé la nécessité de construire des modèles locaux, basés sur une analyse approfondie des données. Les meilleurs modèles obtenus sont ceux pour la masse événementielle qui parviennent à reproduire en tendance la variabilité des observations. La méthode bayésienne a été utilisée pour le test d'un modèle d'Accumulation-Erosion-Transfert simple à l'échelle du bassin versant. Les premiers résultats mettent e défaut la structure du modèle testé. Cependant ces premiers tests ont démontré l'efficacité de la procédure d'analyse bayésienne, dont l'application du principe d'apprentissage permet d'améliorer de manière significative les structures des modèles. / More and more urban water managers are tackling the issue of water quality modelling. Current research works focus on parsimonious modelling approaches that match the amount of data available for calibration. Moreover uncertainties analysis now appears as an integrated step and a powerful tool in models testing. In parallel, development of in sewer continuous measurements based on spectrometry and turbidimetry techniques, provides large data base of continuous total suspended solids and chemical oxygen demand concentrations, providing much information on fluxes dynamics. This research work is one of the first studies in urban hydrology based on a large turbidity data base. Data from two sites have been treated and validated, with measurements over the period 2004-2008. 263 and 239 stormwater events were selected for the modelling work for the two sites. Data analysis provided insights for making assumptions on the pollutant fluxes generation and proposing adapted models. Test of multi-regression approach that it is necessary to build local approaches based on detailed data analysis. Best models were obtained for event mass, data variability could be reproduced in trend. Formal Bayesian approach was used for testing a simple global Accumulation-Erosion-Transfer model for Chassieu. First results evidenced the difficulties of the model to reproduce the dynamics variability. This may be due to the simple structure. However these first tests have demonstrated the efficiency of the Bayesian analysis procedure. ln particular, the application of the learning principle showed that model structure can be significantly and efficiently improved.

L’objectif de ce travail est d’évaluer le transfert des métaux lourds au sein d’une installation de traitement des eaux de ruissellement routier et de développer un procédé épuratoire qui permettrait de parfaire le traitement de ces eaux. La démarche scientifique déployée a d’abord consisté en la caractérisation des flux métalliques acheminés dans un bassin de rétention recevant des eaux de ruissellement provenant d’une autoroute et en l’évaluation du transfert de cette pollution métallique vers la végétation environnante. Les résultats de cette première étude ont permis de mettre en évidence : (1) un transfert des métaux lourds (Cd, Ni, Zn) des compartiments eau – sol vers les macrophytes aquatiques présent sur le site, (2) la capacité de ces macrophytes à accumuler des polluants métalliques au sein de leurs tissus et (3) le caractère bioindicateur de ces macrophytes pour assurer une surveillance de la pollution métallique présente dans les eaux de ruissellement. Compte tenu de la capacité des plantes à accumuler des métaux, en particulier au niveau de leurs racines, un procédé de phytoremediation appelé marais flottant a été proposé pour affiner le traitement des eaux de ruissellement. Les performances épuratoires de ces systèmes ont été évaluées en microcosmes et la faisabilité technique de pouvoir implanter de tels systèmes directement à la surface d’ouvrages existants a également été appréhendée. Les résultats ont démontré que les marais flottants peuvent tout à fait être mis en œuvre à la surface de bassins de rétention sous réserve que les matériaux choisis pour la construction de ces systèmes soient adaptés aux conditions environnementales. Les résultats ont également mis en évidence la capacité des marais flottants à éliminer les métaux présents en phase aqueuse ainsi que l’importance du réseau racinaire qui se développe dans la colonne d’eau sur la rétention des polluants et la filtration des particules fines en suspension. Enfin, cette étude a démontré que les marais flottants peuvent être considérés comme des systèmes de traitement pérennes et nécessitant très peu de maintenance. / The objective of this work is to evaluate the heavy metal transfer into an urban stormwater treatment device and to develop a treatment process which would allow improving the treatment of these waters. The scientific approach consisted first to characterize the metal loads forwarded into a retention pond receiving stormwater runoff coming from a highway and to evaluate the transfer of this metal pollution to the surrounding vegetation. The results of this preliminary study demonstrated: (1) a heavy metal transfer (Cd, Ni and Zn) from the water and soil compartments to the aquatic macrophytes present on the studied site, (2) the capacity of these macrophytes to accumulate metal pollutants into their tissues and (3) the bioindicator value of these macrophytes for biomonitoring of stormwater metal pollution. Regarding the capacity of plants to accumulate metals, especially in their roots, a phytoremediation process called floating treatment wetlands was proposed to improve urban stormwater quality. The treatment performances of these systems were evaluated through a microcosm experiment and the technical feasibility for implanting such floating systems directly on the surface of existing ponds was also evaluated. The results showed that floating treatment wetlands can be operated on the surface of retention pond provided that the material chosen for the construction of these systems are well adapted to environmental conditions. The results also brought to light the efficiency of floating treatment wetlands for metal uptake from water as well as the importance of the root system on pollutant retention and the filtration of fine suspended particles. Finally, this study showed that floating treatment wetlands can be considered as sustainable treatment systems that need low maintenance.

Nonpoint source pollution captured by urban stormwater runoff is the greatest challenge for surface water quality improvements. Computer-based design tools have been developed to help mediate this issue by guiding end users through the implementation of decentralized stormwater management. The majority of these tools focus on treatment via biofiltration, yet concern regarding this treatment regime is rising. Case studies from research past clearly indicate the susceptibility of groundwater to contamination from extensive anthropogenic activity at the surface. Contaminants, such as nitrates and pathogens, are not completely removed before runoff enters the underground watercourse. Additionally, national and state legislation, which explicitly lists where neglect for groundwater quality is permissible—exacerbate concerns. This research analyzes the efficiency the BMP Siting Tool developed by the US Environmental Protection Agency and the Grey-to-Green Decision Support Tool developed by the University of South Florida. The tools were used to obtain cartographic data illustrating suitable sites for bioswales and infiltration basins throughout northern portion of Hillsborough County, Florida. This data was then integrated with the Karst Aquifer Vulnerability Index (KAVI) groundwater vulnerability model. The area of bioswales and infiltration basins that intersected areas of the KAVI model listed as ‘highly vulnerable’ or ‘moderate-to-highly vulnerable’ was calculated. This permitted an assessment of which BMP facility had the greatest sitings atop vulnerable areas, respective of the tool. The BMP Siting Tool sited 2.80% of all bioswales and 27.89% of all infiltration basins above vulnerable areas. Likewise, the Grey-to-Green Decision Support Tool sited 21.66% of all bioswales and 9.62% of all infiltration basins above vulnerable areas. These results prompted the development of a supplemental groundwater vulnerability framework to be incorporated into both tools’ analytical process.

A infiltração das águas de chuva dentro dos lotes urbanos é uma possível forma de promover o controle descentralizado do escoamento superficial na origem, com vistas ao gerenciamento das águas pluviais urbanas e conseqüente atenuação das cheias. Neste trabalho, foram conduzidos ensaios de campo com trincheiras de infiltração, em dois solos distintos, um arenoso e outro argiloso, com o objetivo de avaliar quantitativamente o comportamento hidráulico das estruturas de infiltração em resposta a volumes de escoamento. As trincheiras foram alimentadas com volumes de água controlados, e o campo de umidade do experimento foi monitorado com sonda de nêutrons, durante o processo de redistribuição da água no solo. Foi realizada a modelagem matemática do fenômeno bidimensional de infiltração em torno de trincheiras de seção retangular, em resposta à entrada de águas pluviais provenientes de áreas impermeabilizadas contíguas. A comparação entre os resultados experimentais e simulados pela equação bidimensional de Richards indica uma pequena defasagem dos valores de volume infiltrado e umidade do solo nos processos de infiltração e drenagem interna simulados em relação aos observados. A capacidade de infiltração da trincheira mostrou-se maior nos dados observados, possivelmente devido à simplificação de distribuição unimodal dos diâmetros dos poros adotada na modelagem numérica, uma vez que, experimentalmente, observou-se multimodalidade nos dois solos estudados. A curva de van Genuchten é, juntamente com a equação de Richards, a base do modelo computacional, e divergências no seu ajuste em relação aos dados observados podem conduzir a pequenas divergências dos volumes infiltrados e perfis de umidade ao longo do processo de infiltração simulado, em relação ao observado. São apresentadas algumas considerações de dimensionamento sobre a implantação de trincheiras de infiltração em lotes residenciais, bem como discussões com respeito aos planos diretores urbanos. É apresentado um estudo simplificado, baseado no método racional, sobre a redução no hidrograma de cheia proporcionada pelo uso de trincheiras em uma micro bacia urbana, o qual revelou reduções da ordem de até 94% do deflúvio superficial direto gerado pelo lote. / Stormwater infiltration process at the scale of housing is a possible way to promote the decentralized runoff control in order to manage the urban water and to attenuate flood peaks. In this work, field essays with infiltration devices at two different soils, either sandy and clay-loam soils, are assessed in order to study the hydraulic behavior of infiltration trenches to attenuate incoming runoff volume inputs. The infiltration trench experiments set a controlled water supply for specific boundary conditions, and the experimental moisture field were monitored with neutron probe during the water redistribution process at soil core. Bi-dimensional (2D) mathematical modeling is depicted at specific boundary conditions with a rectangular-trench layout, thereby mimicking a potential situation of runoff incoming from adjacent impervious areas. The comparison between experimental and numerical results, simulated by two-dimensional Richards\' equation, shows a small lag-time difference of both infiltrated volumes and soil moisture contents during infiltration and drainage periods. The trench infiltration capacity of observed data appears to be greater than simulated results, possibly due to an overall simplification of a uni-modal, homogeneous pore diameter distribution adopted by the modeling scheme. Experimental retention curves outline indirect evidences of multi-modal, heterogeneous behavior of pore structure. Bon van Genutchen-type retention curve and Richards-momentum equations represent the baseline approach to the computational model of non-saturated soils. Some fitting discrepancies between observed and simulated results could lead to negligible different estimations of infiltrated volumes and moisture profiles. Finally, further discussions on project design and best management practices (BMPs) of infiltration trenches at housing scale as well discussions on urban master plan are outlined herewith. A simplified study, based on rational method, is presented on the reduction of incoming hydrograph with the use of infiltration trenches. Preliminary results perform volume reductions of approximately 94% from incoming runoff generated at housing lots.

A infiltração das águas de chuva dentro dos lotes urbanos é uma possível forma de promover o controle descentralizado do escoamento superficial na origem, com vistas ao gerenciamento das águas pluviais urbanas e conseqüente atenuação das cheias. Neste trabalho, foram conduzidos ensaios de campo com trincheiras de infiltração, em dois solos distintos, um arenoso e outro argiloso, com o objetivo de avaliar quantitativamente o comportamento hidráulico das estruturas de infiltração em resposta a volumes de escoamento. As trincheiras foram alimentadas com volumes de água controlados, e o campo de umidade do experimento foi monitorado com sonda de nêutrons, durante o processo de redistribuição da água no solo. Foi realizada a modelagem matemática do fenômeno bidimensional de infiltração em torno de trincheiras de seção retangular, em resposta à entrada de águas pluviais provenientes de áreas impermeabilizadas contíguas. A comparação entre os resultados experimentais e simulados pela equação bidimensional de Richards indica uma pequena defasagem dos valores de volume infiltrado e umidade do solo nos processos de infiltração e drenagem interna simulados em relação aos observados. A capacidade de infiltração da trincheira mostrou-se maior nos dados observados, possivelmente devido à simplificação de distribuição unimodal dos diâmetros dos poros adotada na modelagem numérica, uma vez que, experimentalmente, observou-se multimodalidade nos dois solos estudados. A curva de van Genuchten é, juntamente com a equação de Richards, a base do modelo computacional, e divergências no seu ajuste em relação aos dados observados podem conduzir a pequenas divergências dos volumes infiltrados e perfis de umidade ao longo do processo de infiltração simulado, em relação ao observado. São apresentadas algumas considerações de dimensionamento sobre a implantação de trincheiras de infiltração em lotes residenciais, bem como discussões com respeito aos planos diretores urbanos. É apresentado um estudo simplificado, baseado no método racional, sobre a redução no hidrograma de cheia proporcionada pelo uso de trincheiras em uma micro bacia urbana, o qual revelou reduções da ordem de até 94% do deflúvio superficial direto gerado pelo lote. / Stormwater infiltration process at the scale of housing is a possible way to promote the decentralized runoff control in order to manage the urban water and to attenuate flood peaks. In this work, field essays with infiltration devices at two different soils, either sandy and clay-loam soils, are assessed in order to study the hydraulic behavior of infiltration trenches to attenuate incoming runoff volume inputs. The infiltration trench experiments set a controlled water supply for specific boundary conditions, and the experimental moisture field were monitored with neutron probe during the water redistribution process at soil core. Bi-dimensional (2D) mathematical modeling is depicted at specific boundary conditions with a rectangular-trench layout, thereby mimicking a potential situation of runoff incoming from adjacent impervious areas. The comparison between experimental and numerical results, simulated by two-dimensional Richards\' equation, shows a small lag-time difference of both infiltrated volumes and soil moisture contents during infiltration and drainage periods. The trench infiltration capacity of observed data appears to be greater than simulated results, possibly due to an overall simplification of a uni-modal, homogeneous pore diameter distribution adopted by the modeling scheme. Experimental retention curves outline indirect evidences of multi-modal, heterogeneous behavior of pore structure. Bon van Genutchen-type retention curve and Richards-momentum equations represent the baseline approach to the computational model of non-saturated soils. Some fitting discrepancies between observed and simulated results could lead to negligible different estimations of infiltrated volumes and moisture profiles. Finally, further discussions on project design and best management practices (BMPs) of infiltration trenches at housing scale as well discussions on urban master plan are outlined herewith. A simplified study, based on rational method, is presented on the reduction of incoming hydrograph with the use of infiltration trenches. Preliminary results perform volume reductions of approximately 94% from incoming runoff generated at housing lots.

La prise de conscience grandissante de la contamination des cours d'eau a entraîné l'établissement de réglementations de plus en plus strictes concernant les rejets urbains et la fixation d'objectifs de qualité à atteindre pour les milieux aquatiques. Cependant, l'échantillonnage ponctuel reste une limite importante dans l'estimation des flux de contaminants, et le besoin de suivis en continu est présent dans le milieu naturel et dans les réseaux d'assainissement urbains. Cette étude porte sur la quantification de la part des rejets urbains de l'agglomération grenobloise dans les flux totaux de matières en suspension (MES), nutriments (azote, phosphore), carbone organique et éléments traces métalliques (ETM) du milieu récepteur Isère (une rivière alpine). Ce travail s'est appuyé sur un réseau de mesures en continu de débits (Q) et de MES (par turbidimétrie) à l'amont et à l'aval de l'agglomération et sur une sonde spectrométrique à l'amont, associé à des campagnes de prélèvements réguliers et renforcés pendant les épisodes de crues. Des campagnes de mesures détaillées sur les principaux sous bassins du réseau d'assainissement ont été réalisées durant la période d'étude dans le cadre du schéma directeur d'assainissement de l'agglomération grenobloise. Le croisement de ces deux approches a permis de confronter les variations spatio-temporelles des MES, nutriments, carbone organique et ETM du réseau et du milieu récepteur en 2011 et 2012. Les flux sur ces deux années ont été établis afin de déterminer la contribution des rejets urbains dans les flux du milieu récepteur. La contamination en mercure a fait l'objet d'un suivi particulier du fait de la présence d'une source significative de mercure dans la région. Enfin, une réflexion sur l'amélioration des calculs de flux par l'utilisation de relations entre les ETM/carbone organique particulaire (COP) et un paramètre mesurable en continu (MES, Q) a été menée en parallèle de l'exploitation de ces résultats. Mots-clés : Matières en suspension ; Dynamique des flux ; Nutriments ; Eléments traces métalliques ; Mercure ; Rejets urbains (par temps de pluie et temps sec), sondes de turbidité et spectrométrique. / The growing awareness of the contamination of rivers has led to the establishment of more rigorous regulations related to urban waste, and to the setting of water quality objectives to be achieved for aquatic environment. However, grab sampling remains an important limitation for the estimation of contaminant flux, and the need for constant monitoring is present in both natural environment and urban sanitation. This study focuses on the quantification of the proportion of urban waste in the Grenoble area to the total flux of 1) suspended solids (TSS), 2) nutrients (nitrogen and phosphorus), 3) organic carbon and 4) metals trace element (MTE) of the receiving environment; the Isère (an alpine river). This work was supported by a network of continuous discharge measurements (Q) and TSS (turbidimetry), both upstream and downstream of Grenoble associated with regular sampling campaigns, with a higher measurement frequency during flood events. A spectrometric probe upstream was also placed upstream. Detailed measurement campaigns on major sub-basins of the sewerage network were performed during the study period as part of the sanitation master plan of Grenoble. The combination of these two approaches allowes to relate the spatio-temporal variations of TSS, nutrients, organic carbon and MTE in the urban water network of Grenoble and in the receiving environment (the Isère) for the years 2011 and 2012. Flows of the traced parameters have been established to determine the contribution of urban waste flows in the receiving environment, over these two years. Finally, a study on how to improve the flow calculations by the use of relations between MTE / particulate organic carbon (POC ) and a continuous measurable parameter (MES, Q ) was conducted in parallel with these results. Key words: suspended solids, Nutrients, metals trace element; Mercury; urban waste; turbidimetry and spectrometric probe

This diploma thesis presents the topic of urban drainage systems. The first theoretical part contains methods and options for urban drainage systems, stormwater management, blue-green infrastructure (BGI) in urban areas and introduction of numerical modelling of sewerage systems. The application of modelling platforms is further described in the feasibility study in the practical part of this thesis. By using the simulation model, the study assesses the hydraulic reliability of the drainage system in the city of Jedovnice in the Czech Republic, identifies hydraulic issues and their causes on the urban drainage system. The second part of the study assesses extra-urban stormwater inflow from fields around the city caused by heavy rainfalls, which causes local flooding in the urban area. The identification as well as proposed solutions and capital expenditures, their comparison and recommendation of the optimal solution are included in the study.

Low Impact Development (LID) is a sustainable stormwater management approach that aims to control runoff close to its source, mimicking the natural hydrological processes such as infiltration and storage. It is being adopted by many cities, where its implementation is rapidly evolving. The LID practices are small-scale measures; therefore, they need to be widely implemented to impact significantly. The selection of LIDs depends on the land use and characteristics of the area of interest. This study focuses on residential LIDs. First, a systematic and bibliometric literature review is conducted on the residential LIDs articles published up to the year 2020; a total of 94 papers were found in the Web of Science. This review resulted that LID implementation in residential areas still needs to be investigated. To assist the City, engineers, and policy-makers in implementing the suitable LIDs for detached houses, a multi-criteria decision analysis framework incorporating a hydrological model is developed in this study. The commonly used LIDs were identified, which are rain gardens, permeable pavement, rain barrels, soakaways. Seven criteria were selected – runoff depth reduction rate, peak runoff reduction rate, installation cost, maintenance cost, retrofit cost, life cycle, and aesthetical view. For the properties of the single-detached house and LIDs, the standards of Credit Valley Conservation (CVC) and Toronto and Region Conservation Authority (TRCA) were followed. The proposed decision-making framework also was applied to a case study. This framework is still in the preliminary stage, thus holds the potential to convert into a tool that will be handy enough for the homeowners and consume less time. / Thesis / Master of Applied Science (MASc)