Separate sewers are more and more preferred over combined ones but are sensitive to misconnections. Several inspection techniques (time consuming and expensive) are specifically devoted to detecting such misconnections: smoking test and dye tracing are the most popular. This paper presents a new, low-cost and easy to apply method based on 3D printed pills. Numbered (with a unique code) and coloured (blue or red) pills are thrown in toilets, washbowls etc. and then collected in sewers. After an automatic treatment of the collected pills in both the wastewater and the storm water system, the comparison between the sent and collected pill databases allows the identification and the location (inside the building itself) of the misconnections present. Pill and pill analyser designs, analysis methods and on-line tools are described on this paper. Social acceptability and legal issues are briefly discussed.@en

Sewer inspections are usually done with CCTV. For a decade, emerging techniques have been developed and drones seem to offer new opportunities. The use of a velocity profiler is investigated in this study in order to identify and quantify velocities distributions created by lateral connection along a pipe. Disturbances created by such connections are detectable but further investigations are required to quantify the discharge from the lateral connection.@en

Les réseaux d’assainissement séparatifs sont de plus en plus préférés aux réseaux unitaires mais ils sont sensibles aux erreurs (in)volontaires de branchements entre les bâtiments et le réseau. Il existe quelques techniques d’inspections spécifiques à ce type de recherche : les tests à la fumée et aux colorants sont les plus utilisés. Ces techniques restent chères et chronophages. Cette étude présente une nouvelle méthode, simple et bon marché, basée sur des pilules imprimées en 3d. Ces pilules, numérotées (avec un code unique) et colorées (bleu ou rouge), sont envoyées par courrier aux habitants, jetées à différents points (toilettes, gouttières, etc.) puis collectées dans les réseaux. Après une analyse automatique des pilules récupérées, une comparaison entre les bases de données des pilules jetées et collectées permet l’identification et la localisation des erreurs de branchements (à l ‘intérieur même des bâtiments). Les conceptions de pilules et de l’analyseur, les méthodes d’analyses et les outils en ligne sont décrits dans ce résumé. L’acceptabilité sociale de la méthode est brièvement discutée. Des tests in situ sont prévus aux Pays-Bas et en France d’ici la conférence. Separate sewers are more and more preferred than combined ones but are sensitive to (in)voluntary mistakes in the connections between buildings and the network. There are only a few inspection techniques specifically devoted to such investigations: smoking test and dye tracing are the most popular. Those techniques are time consuming and expensive. This paper presents a new, low-cost and easy method based on 3D printed pills. Numbered (with a unique code) and coloured (blue or red) pills are sent by mail to inhabitants, thrown in different locations (toilets, downpipes, etc.) and then collected in sewers. After an automatic treatment of the collected pills, the comparison between the sent and collected pill databases allows the identification and the location (inside the building itself) of the misconnections. Pill and pill analyser designs, analysis methods and on-line tools are described on this paper. Social acceptability is briefly discussed. Some in situ tests will take place in France and in the Netherlands before the conference. @en

In order to propose a new sewer inspection method, a velocity/turbidity profiler (Ubertone, UB Flow) has been tested in a laboratory. A 50 m glass flume has been adapted with several lateral connections (with a arnge of diameter, angle, intrusions, cracks), supplied by a 1 m3 tank. Placed just below the free surface on a rotating (to scan the wet section) and translating (along the main axe of the flume) structure, velocity profiles have been recorded and accurately positioned along the reach (with data from three laser distance meters and a 3 Mpix camera): a 3D cloud of raw velocities is created. After raw data pretreatment (deduction of translation velocity, Nyquist jumps correction, low quality data removal i.e. with low SNR threshold and vector projection corrections), five step-interpolation (adapted from [1]) methods have been implemented and tested: i) data filtering, ii) transformation to flume coordinates velocities, iii) isotropic gridding, iv) anisotropic gridding and v) continuity correction. These methods aim to produce contour lines and the quantification of different streamlines in the reach.@en