No description available.

<p>The aim of this project was to look into ten small sewer systems in the municipality of Laholm, in Sweden, in order to work out common assessment grounds for them. The sizes of the systems for purification of wastewater were within the range of 25 to 2000 population equivalents. Our method was to study literature, the laws and regulations applicable and the files at the municipality. The conclusion is that every sewer system is different and every situation is unique. We concluded that based on laws and assessment grounds sewer systems equal in size and pollution load ought to have similar demands attached to them. Four of the sewer systems are in need of adjustments or renovations. One sewer system in particular, Hishult, needs large-scale adjustments and improvements to live up to the demands attached to it. This sewer system is where we think the focus from the municipality ought to be the strongest, based on the result from this review. It requires most effort, time and money, to get it running with least amount of environmental impact. We also suggested levels for degree of purification for all of the sewer systems. As a common ground we set the demands equal to the ones for private sewer systems. The demand for purification of phosphorus was adjusted to if the system was equipped with chemical precipitation or not. Subsurface filters are left without measures. The focus of demands on systems of that kind is set to new construction or full scale restoration.</p>

The aim of this project was to look into ten small sewer systems in the municipality of Laholm, in Sweden, in order to work out common assessment grounds for them. The sizes of the systems for purification of wastewater were within the range of 25 to 2000 population equivalents. Our method was to study literature, the laws and regulations applicable and the files at the municipality. The conclusion is that every sewer system is different and every situation is unique. We concluded that based on laws and assessment grounds sewer systems equal in size and pollution load ought to have similar demands attached to them. Four of the sewer systems are in need of adjustments or renovations. One sewer system in particular, Hishult, needs large-scale adjustments and improvements to live up to the demands attached to it. This sewer system is where we think the focus from the municipality ought to be the strongest, based on the result from this review. It requires most effort, time and money, to get it running with least amount of environmental impact. We also suggested levels for degree of purification for all of the sewer systems. As a common ground we set the demands equal to the ones for private sewer systems. The demand for purification of phosphorus was adjusted to if the system was equipped with chemical precipitation or not. Subsurface filters are left without measures. The focus of demands on systems of that kind is set to new construction or full scale restoration.

Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Waterborne sewage system design and expansion objectives are often focused on minimising initial investment while increasing system capacity and meeting hydraulic requirements. Although these objectives make good sense in the short term, the solutions obtained might not represent the optimal cost-effective solution to the complete useful life of the system. Maintenance and operation of any system can have a significant impact on the life-cycle cost. The costing process needs to be better understood, which include maintenance and operation criteria in the design of a sewer system. Together with increasing public awareness regarding global warming and environmental degradation, environmental impact, or carbon cost, is also an important factor in decisionmaking for municipal authorities. This results in a multiplicity of different objectives, which can complicate the decisions faced by waterborne sewage utilities. Human settlement and migration is seen as the starting point of expansion problems. An investigation was conducted into the current growth prediction models for municipal areas in order to determine their impact on future planning and to assess similarities between the models available. This information was used as a platform to develop a new method incorporating indirect costs into models for planning waterborne sewage systems. The need to balance competing objectives such as minimum cost, optimal reliability, and minimum environmental impact was identified. Different models were developed to define the necessary criteria, thus minimising initial investment, operating cost and environmental impact, while meeting hydraulic constraints. A non-dominated sorting genetic algorithm (NSGA-II) was applied to certain waterborne sewage system (WSS) scenarios that simulated the evolutionary processes of genetic selection, crossover, and mutation to find a number of suitable solutions that balance all of the given objectives. Stakeholders could in future apply optimisation results derived in this thesis in the decision making process to find a solution that best fits their concerns and priorities. Different models for each of the above-mentioned objectives were installed into a multi-objective NSGA and applied to a hypothetical baseline sewer system problem. The results show that the triple-objective optimisation approach supplies the best solution to the problem. This approach is currently not applied in practice due to its inherent complexities. However, in the future this approach may become the norm. / AFRIKAANSE OPSOMMING: Spoelafvoering rioolstelsel ontwerp en uitbreiding doelwitte is dikwels gefokus op die vermindering van aanvanklike belegging, terwyl dit die verhoging van stelsel kapasiteit insluit en ook voldoen aan hidrouliese vereistes. Alhoewel hierdie doelwitte goeie sin maak in die kort termyn, sal die oplossings verkry dikwels nie die optimale koste-effektiewe oplossing van die volledige nuttige lewensduur van die stelsel verteenwoordig nie. Bedryf en instandhouding van 'n stelsel kan 'n beduidende impak op die lewensiklus-koste hê, en die kostebepalings proses moet beter verstaan word en die nodige kriteria ingesluit word in die ontwerp van 'n rioolstelsel. Saam met 'n toenemende openbare bewustheid oor aardverwarming en die agteruitgang van die omgewing, is omgewingsimpak, of koolstof koste, 'n belangrike faktor in besluitneming vir munisipale owerhede. As gevolg hiervan, kan die diversiteit van die verskillende doelwitte die besluite wat munisipale besluitnemers in die gesig staar verder bemoeilik. Menslike vestiging en migrasie is gesien as die beginpunt van die uitbreiding probleem. 'n Ondersoek na die huidige groeivoorspelling modelle vir munisipale gebiede is van stapel gestuur om hul impak op die toekomstige beplanning te bepaal, en ook om die ooreenkomstes tussen die modelle wat beskikbaar is te asesseer. Hierdie inligting is gebruik as 'n platform om ‘n nuwe metode te ontwikkel wat indirekte kostes inkorporeer in die modelle vir die beplanning van spoelafvoer rioolstelsels. Die behoefte is geïdentifiseer om meedingende doelwitte soos minimale aanvanklike koste, optimale betroubaarheid en minimum invloed op die omgewing te balanseer. Verskillende modelle is ontwikkel om die bogenoemde kriteria te definiëer, in die strewe na die minimaliseering van aanvanklike belegging, bedryfskoste en omgewingsimpak, terwyl onderhewig aan hidrouliese beperkinge. ‘n Nie-gedomineerde sorteering genetiese algoritme (NSGA-II), istoegepas op sekere spoelafvoering rioolstelsel moontlikhede wat gesimuleerde evolusionêre prosesse van genetiese seleksie, oorplasing, en mutasie gebruik om 'n aantal gepaste oplossings te balanseer met inagname van al die gegewe doelwitte. Belanghebbendes kan in die toekoms gebruik maak van die resultate afgelei in hierdie tesis in besluitnemings prosesse om die bes-passende oplossing vir hul bekommernisse en prioriteite te vind. Verskillende modelle vir elk van die bogenoemde doelwitte is geïnstalleer in die nie-gedomineerde sorteering genetiese algoritme en toegepas op 'n hipotetiese basislyn rioolstelsel probleem. Die resultate toon dat die drie-objektief optimalisering benadering die beste oplossing vir die probleem lewer. Hierdie benadering word tans nie in die praktyk toegepas nie, as gevolg van sy inherente kompleksiteite. Desnieteenstaande, kan hierdie benadering in die toekoms die norm word.

Magistro studijų baigiamasis darbas, 58 puslapiai, 46 paveikslai, 10 lentelės, 32 literatūros šaltiniai, 9 lietuvių kalba ir 23 už sienio kalba Tyrimo objektas – Vakuuminis ir savitakinis nuotakynas. Darbo tikslas – atlikti vakuuminio ir savitakinio nuotakyno palyginamąją analizę. Uždaviniai: 1. Išanalizuoti sistemų privalumus ir trūkumus; 2. Suprojektuoti savitakinį ir vakuuminį tinklą pasirinktai gyvenvietei; 3. Atlikti suprojektuotų tinklų ekonominė analizė Tyrimo metodai – lietuvių ir už sienio mokslinės literatūros lyginamoji analizė, scheminio vaizdavimo metodas, projektavimas. Išstudijavus Lietuvių ir užsienio literatūrą apie vakuuminį bei savitakinį nuotakyną, apžvelgta dabartinė nuotakynų būklė Lietuvoje, atlikta palyginamoji analizė, nustatyti pagrindiniai sistemų privalumai bei trūkumai, apžvelgtos vakuuminės sistemos pritaikymo sritys. Vilniaus raj. Sakališkių gyvenvietei suprojektuoto vakuuminio bei savitakinio tinklo analizė parodė, kad vakuuminio nuotakyno statybos kaštai yra beveik dvigubai mažesni negu savitakinio. Atlikta analizė parodė, kad vakuuminiai nuotakynai yra perspektyvūs tam tikromis sąlygomis, tačiau Lietuvoje nepagristai nenaudojami. Vakuuminiai nuotakynai yra nepakeičiami projektuojant lygiose, retai apgyvendintose kaimiškose vietovėse. Priimant sprendimą dėl gyvenvietės nuotekų sistemos pasirinkimo, turi būti atliktas bent dviejų skirtingų sistemų variantų palyginimas. / Master degree final work consists of 58 pages, 46 pictures, 10 tables and 32 literatures. Test object – Vacuum and gravity system. Work purpose is to perform vacuum and gravity sewer system’s comparison analysis. Main tasks: 1. Analyze systems advantages and disadvantages; 2. Project gravity and vacuum systems for chosen village; 3. Perform economical analysis for projected systems; Test methods are Lithuanian and foreign scientific literatures comparison analysis, schematic representation method, planning. Overviewed Lithuanian and foreign scientific literature about vacuum and gravity sewer system was overlooked now days sewer situation in Lithuania, completed systems comparison analysis, identified the main systems advantages and disadvantages, overlooked vacuum sewer systems appliances areas, for Sakaliskes village was projected vacuum and gravity systems. Accomplished analysis showed that vacuum sewers are perspective under certain conditions, but in Lithuania interfere unused. Vacuum sewers are unchangeable in flat territories and in rural areas. Before project starts, there should be completed comparison of vacuum, gravity and pressure sever systems.

Este trabalho descreve os diversos materiais que podem ser utilizados nas tubulações de sistemas de esgotos sanitários, apresenta suas principais características, a hidráulica das tubulações, principais fabricantes, aspectos construtivos, operação e manutenção e comentam-se as normas técnicas referentes a esses materiais. Os dados apresentados foram obtidos através de pesquisa na área norte de São Paulo cujo sistema é operado pela Sabesp, consultando-se as unidades funcionais de projeto, apoio técnico, operação, manutenção e obras da Sabesp. Destaca-se a preferência pelo uso das tubulações de PVC para a implantação e manutenção das ligações prediais e redes coletoras devido às vantagens de sua aplicação, tais como: facilidade de transporte e manuseio, maior produtividade, menos problemas operacionais, praticidade e segurança. Para coletores de maiores diâmetros e interceptores há preferência pelos tubos de PRFV, PVC e PEAD e pelo sistema de tubo de concreto cravado. Na escolha do melhor material a ser utilizado, deve-se considerar além das características dos esgotos, a resistência, a disponibilidade, a facilidade de transporte, e custos desse material . Deve-se, também se levar em conta, o método aplicado na construção e as condições locais da obra. Como principais conclusões, destaca-se a viabilidade econômica da utilização do PVC em relação ao tubo cerâmico nas obras de redes e ligações, e a tendência da utilização de PRFV e PEAD na implantação de novos coletores com diâmetro de 300 a 500mm. Recomenda-se a utilização de juntas elásticas nas tubulações cerâmicas e a especificação do tipo de material precedida de estudos amplos de viabilidade que considerem a sua vida útil, praticidade de aplicação, custos, aspectos ambientais, operação, manutenção, segurança e rapidez na implantação da obra. / This dissertation describes the various materials used in sanitary sewer systems, presents their main characteristics, pipeline hydraulics and manufacturers. It also features construction, operational and maintenance aspects for the different materials as well as the technical regulations concerning these materials. Data were collected in the Northern area of São Paulo, whose sewer system is operated by Sabesp, through research in the following functional units: project, technical support, operations, maintenance and construction. This study highlights the operation area\'s preference for PVC pipes for building and maintenance of sewage connections and sewers because its advantages such as: ease of transportation and handling, greater productivity, less operational problems, practicity and safety. For large diameter trunk sewers and interceptors, FRP (Fiberglass reinforced plastic), PVC (Polyvinyl chloride) and PE (Polyethylene) pipes and Jacking Pipe system are usually the choice. In the selection of the best material, one should consider the wastewater characteristics and the material resistance, availability, ease of transportation and cost. The construction methods and local conditions should also be taken into account in this process. In conclusion, this study stresses the economical viability of PVC pipes over ceramical pipes in sewers and connections, the tendency to use FRP and PE in new 300 - to 500- mm- diameter trunk sewers and recommendation for the use of elastic joints with ceramical pipes. Lastly, the specification of the type of material to be used should be preceded by broad viability studies that consider its required life, practicity, cost, environmental aspects, operational and maintenance aspects and safety in the building process.

La corrosión del concreto es uno de los principales problemas de deterioro y pérdida de funcionalidad que puede llevar al colapso parcial o total de una estructura. En los sistemas de alcantarillado existe un proceso denominado Corrosión Microbiana Inducida, el cual es causado por la acción del consorcio de bacterias presentes en las aguas residuales, las mismas que generan ácido sulfúrico como parte de su metabolismo. El trabajo experimental desarrollado comienza con la preparación y muestreo de un diseño de concreto patrón y tres de concreto antibacterial con diferente dosificación de Aditivo Antimicrobial, los cuales fueron evaluados por un ensayo microbiológico. En esta etapa se determinó la dosis de aditivo con la que se realizarán nuevos diseños. Como alternativa de solución frente al ataque de ácido sulfúrico se realizó en laboratorio la preparación y muestreo de seis diseños de concreto, para los cuales se establece algunas variables de estudio: relación agua/cemento y porcentaje de adición mineral Filler Calizo. Las propiedades del concreto se evaluaron mediante ensayos en estado endurecido. Asimismo, se determinó la resistencia del concreto frente a concentraciones de 3%, 5% y 7% de ácido sulfúrico; el rendimiento se evaluó mediante la pérdida de peso. Finalmente, se realizó una evaluación económica en base a un proyecto de Saneamiento, en el cual se determinó el presupuesto para la construcción de buzones considerando los costos del concreto patrón y antibacterial elegido. Para determinar la rentabilidad económica se consideró los costos por mantenimiento para un periodo de análisis de 20 años. / The experimental work developed begins with the preparation and sampling of a single concrete pattern design and three antibacterial concrete designs with different dosage of Antimicrobial Additive, which are evaluated through a microbiological test. This consists in the exposure of the concrete samples at the consortium of bacteria present in a wastewater treatment plant. The effectiveness of the additive under study was determined by a visual analysis of the coloration, pH variation and then compared to the results of the concrete pattern design. As an alternative solution for sulfuric acid attack, the preparation, sampling and control of six concrete designs was carried out in laboratory, for which some study variables were established: the water / cement ratio and the mineral addition percentage of Filler Limestone. The durability of the concrete was evaluated by hardened destructive and non-destructive tests. Likewise, the resistance of the concrete was determined against concentrations of 3%, 5% and 7% of sulfuric acid, for an exposure time of 4 and 8 weeks and analyzed by the weight loss. Finally, an economic evaluation was carried out based on a sanitary project, in which the budget for the construction of mailboxes was determined considering the costs of the standard and antibacterial concrete previously chosen. To determine the benefit, a schedule was established with the items of preventive and corrective maintenance according to the frequency and necessity of each design. The results were presented through a flow of expenditures for a period of analysis of 20 years. / Tesis

Este trabalho descreve os diversos materiais que podem ser utilizados nas tubulações de sistemas de esgotos sanitários, apresenta suas principais características, a hidráulica das tubulações, principais fabricantes, aspectos construtivos, operação e manutenção e comentam-se as normas técnicas referentes a esses materiais. Os dados apresentados foram obtidos através de pesquisa na área norte de São Paulo cujo sistema é operado pela Sabesp, consultando-se as unidades funcionais de projeto, apoio técnico, operação, manutenção e obras da Sabesp. Destaca-se a preferência pelo uso das tubulações de PVC para a implantação e manutenção das ligações prediais e redes coletoras devido às vantagens de sua aplicação, tais como: facilidade de transporte e manuseio, maior produtividade, menos problemas operacionais, praticidade e segurança. Para coletores de maiores diâmetros e interceptores há preferência pelos tubos de PRFV, PVC e PEAD e pelo sistema de tubo de concreto cravado. Na escolha do melhor material a ser utilizado, deve-se considerar além das características dos esgotos, a resistência, a disponibilidade, a facilidade de transporte, e custos desse material . Deve-se, também se levar em conta, o método aplicado na construção e as condições locais da obra. Como principais conclusões, destaca-se a viabilidade econômica da utilização do PVC em relação ao tubo cerâmico nas obras de redes e ligações, e a tendência da utilização de PRFV e PEAD na implantação de novos coletores com diâmetro de 300 a 500mm. Recomenda-se a utilização de juntas elásticas nas tubulações cerâmicas e a especificação do tipo de material precedida de estudos amplos de viabilidade que considerem a sua vida útil, praticidade de aplicação, custos, aspectos ambientais, operação, manutenção, segurança e rapidez na implantação da obra. / This dissertation describes the various materials used in sanitary sewer systems, presents their main characteristics, pipeline hydraulics and manufacturers. It also features construction, operational and maintenance aspects for the different materials as well as the technical regulations concerning these materials. Data were collected in the Northern area of São Paulo, whose sewer system is operated by Sabesp, through research in the following functional units: project, technical support, operations, maintenance and construction. This study highlights the operation area\'s preference for PVC pipes for building and maintenance of sewage connections and sewers because its advantages such as: ease of transportation and handling, greater productivity, less operational problems, practicity and safety. For large diameter trunk sewers and interceptors, FRP (Fiberglass reinforced plastic), PVC (Polyvinyl chloride) and PE (Polyethylene) pipes and Jacking Pipe system are usually the choice. In the selection of the best material, one should consider the wastewater characteristics and the material resistance, availability, ease of transportation and cost. The construction methods and local conditions should also be taken into account in this process. In conclusion, this study stresses the economical viability of PVC pipes over ceramical pipes in sewers and connections, the tendency to use FRP and PE in new 300 - to 500- mm- diameter trunk sewers and recommendation for the use of elastic joints with ceramical pipes. Lastly, the specification of the type of material to be used should be preceded by broad viability studies that consider its required life, practicity, cost, environmental aspects, operational and maintenance aspects and safety in the building process.

<p>Sewer pipelines are an essential component of wastewater infrastructure and serve as the primary means for transporting wastewater to treatment plants. In the face of increasing demands and declining budgets, municipalities across the US face unprecedented challenges in maintaining current service levels of the 800,000 miles of public sewer pipes. Inadequate maintenance of sewer pipes leads to inflow and infiltration, sanitary sewer overflows, and sinkholes, which threaten human health and are expensive to correct. Accurate condition information from sewers is essential for planning maintenance, repair, and rehabilitation activities and ensuring the longevity of sewer systems. Currently, this information is obtained through visual closed-circuit television (CCTV) inspections and deterioration modeling of sewer pipelines. CCTV inspection facilitates the identification of defects in pipe walls whereas deterioration modeling estimates the remaining service life of pipes based on their current condition. However, both methods have drawbacks that limit their effective usage for sewer condition assessment. For instance, CCTV inspections tend to be labor intensive, costly, and time consuming, with the accuracy of collected data depending on the operator’s experience and skill level. Current deterioration modeling approaches are unable to incorporate spatial information about pipe deterioration, such as the relative locations, densities, and clustering of defects, which play a crucial role in pipe failure. This study attempts to leverage recent advances in deep learning and data mining to address these limitations of CCTV inspection and deterioration modeling and consists of three objectives. </p> <p> </p> <p>The first objective of this study seeks to develop algorithms for automated defect interpretation, to improve the speed and consistency of sewer CCTV inspections. The development, calibration, and testing of the algorithms in this study followed an iterative approach that began with the development of a defect classification system using a 5-layer convolutional neural network (CNN) and evolved into a two-step defect classification and localization framework, which combines a the ResNet34 CNN and Faster R-CNN object detection model. This study also demonstrates the use of a feature visualization technique, called class activation mapping (CAM), as a diagnostic tool to improve the accuracy of CNNs in defect classification tasks—thereby representing a crucial first step in using CNN interpretation techniques to develop improved models for sewer defect identification. </p> <p> </p> <p>Extending upon the development of automated defect interpretation algorithms, the second objective of this study attempts to facilitate autonomous navigation of sewer CCTV robots. To overcome Global Positioning System (GPS) signal unavailability inside underground pipes, this study developed a vision-based algorithm that combines deep learning-based object detection with optical flow for estimating the orientation of sewer CCTV cameras. This algorithm can enable inspection robots to estimate their trajectories and make corrective actions while autonomously traversing pipes. Hence, considered together, the first two objectives of this study pave the way for future inspection technologies that combine automated defect interpretation with autonomous navigation of sewer CCTV robots.</p> <p> </p> <p>The third and final objective of this study seeks to develop a novel methodology that incorporates spatial information about defects (such as their locations, densities, and co-occurrence characteristics) when assessing sewer deterioration. A methodology called Defect Cluster Analysis (DCA) was developed in order to mine sewer inspection reports and identify pipe segments that contain clusters of defects (i.e., multiple defects in proximity). Additionally, an approach to mine co-occurrence characteristics among defects is also introduced (i.e., identification of defects which occur frequently together). Together the two approaches (i.e., DCA and co-occurrence mining) address a key limitation of existing deterioration modeling approaches (i.e., the lack of consideration to spatial information about defects)—thereby leading to the generation of new insights into pipeline rehabilitation decision-making. </p> <p> </p> <p>The algorithms and approaches presented in this dissertation have the potential to improve the speed, accuracy, and consistency of assessing sewer pipeline deterioration, leading to better prioritization strategies for maintenance, repair, and rehabilitation. The automated defect interpretation algorithms proposed in this study can be used to assign the subjective and error-prone task of defect identification to computer processes, thereby enabling human operators to focus on decision-making aspects, such as deciding whether to repair or rehabilitate a pipe. Automated interpretation of sewer CCTV videos could also facilitate re-evaluation of historical sewer inspection videos, which would be infeasible if performed manually. The information gleaned from re-evaluating these videos could generate insights into pipe deterioration, leading to improved deterioration models. The algorithms for autonomous navigation could enable the development of completely autonomous inspection platforms that utilize unmanned aerial vehicles (UAVs) or similar technologies to facilitate rapid assessment of sewers. Furthermore, these technologies could be integrated into wireless sensor networks, paving the way for real-time condition monitoring of sewer infrastructure. The DCA approach could be used as a diagnostic tool to identify specific sections in a pipeline system that have a high propensity for failure due to the existence of multiple defects in proximity. When combined with contextual information (e.g., soil properties, water table levels, and presence of large trees), DCA could provide insights about the likelihood of void formation due to sand infiltration. The DCA approach could also be used to periodically determine how the distribution of defects and their clustering progresses with time and when examined alongside contextual data (e.g., soil properties, water table levels, presence of trees) could reveal trends in pipeline deterioration. </p>

Cette thèse valorise les données de mesure en continu de pluie de débit et de turbidité, ainsi que les bases de donnée de résultat d'analyse et les connaissances acquises dans le cadre des trois observatoires français en hydrologie urbaine, OPUR-Paris, OTHU-Lyon et ONEVU Nantes, pour valider et améliorer les connaissances sur les flux et les sources de particules vectrices de contaminants, en réseaux d'assainissement unitaire. Les données provenant de 6 sites expérimentaux drainés par un réseau d'assainissement unitaire ont été exploitées : Marais, Quais et Clichy à Paris, Cordon Bleu et Saint-Mihiel à Nantes et Écully à Lyon, avec sur chaque site des bases de données de longue durée qui ont permis des études statistiques sur des échantillons de plusieurs dizaines d'événements pluvieux et de journées de temps sec. Cette thèse a permis : 1- d'évaluer la représentativité de la turbidité pour analyser du transport solide en réseau ; 2- d'analyser et de modéliser statistiquement les concentrations et les masses de particules à l'échelle événementielle ; 3- d'étudier la dynamique des flux et des concentrations à l'échelle intra-événementielle. Les résultats obtenus indiquent d'une part, que la turbidité permet de décrire les dynamiques intra-événementielles des flux et des concentrations à condition d'exprimer ceux-ci sous forme relative, normalisée par les valeurs moyennes événementielles. En revanche, ces valeurs événementielles sont attachées par des erreurs systématiques non négligeables induites par les variations inter-événementielles de la relation MES-Turbidité (intervalle de confiance de l'ordre de 30% de la moyenne). Ils confirment d'autre part que la contribution des dépôts aux flux de temps de pluie est importante mais variable (entre 20 et 80% de la masse à l'exutoire selon l'événement), y compris sur un site réputé exempt de dépôts (grossiers). Autrement dit, les problématiques d'ensablement et de pollution de temps de pluie ne sont pas nécessairement liées. L'autre contribution majeure est celle des eaux usées « de temps sec ». De plus, ils nous ont permis de progresser dans la compréhension des phénomènes de décalage temporel entre hydrogramme et pollutogramme et d'effet piston / This thesis exploits continuous measurement of rainfall, discharge and turbidity data and the knowledge acquired by three French observatories in urban hydrology, OPUR-Paris, OTHU Lyon and ONEVU-Nantes, to validate and improve knowledge on suspended solids discharges and sources of particles, which are major vectors of contaminants in combined sewer systems. Data from six experimental sites served by a combined sewer system were used: Marais, Quais and Clichy in Paris, Cordon Bleu and Saint-Mihiel in Nantes and Ecully in Lyon. At each site, a long duration databases enabled statistical studies on samples of several tens of rainfall events and dry weather days. This thesis allowed: 1-to assess the representativeness of turbidity to analyze sediments transport in network; 2-to analyze and model concentrations and masses of particles at the scale of rain events; 3-to study the dynamics of fluxes and concentrations at intra-event scale. Results show that turbidity can describe the dynamics of intra-event fluxes and concentrations provided these are expressed in a relative form, normalized by the event mean values. However, these mean values are attached by significant systematic errors induced by variations of the inter-event TSS-turbidity relationship (95% confidence interval about 30% of average). The contribution of sewer deposits to wet weather suspended solids discharges is important but variable (between 20 and 80% of the mass at the outlet depending on the event), including for a site allegedly free of (coarse) sewer deposits. In other words, the problems of silting and contribution from deposits to wet weather pollution are not necessarily related. The other major contribution is from “dry weather” wastewater. In addition, they we made some progress in understanding the lag-time phenomena between hydrograph and pollutograph and the piston effect