Disinfection by products estimation in a water distribution network

Even though disinfection is necessary to ensure water safety for human consumption, some disinfectants produce disinfection by-products (DBPs) that may be dangerous for human health. Current European legislation obligates water distributors to limit some DBPs concentration to final consumers. Then, water companies must control these compounds and are obligated to periodically monitor their network. DBPs modeling can be very useful for estimating online DBPs concentration throughout the network, increasing DBPs control and knowledge, but avoiding DBPs analytics time and resources consumption [1]. Trihalomethanes (THM), the first DBPs discovered, have long been the most studied and modeled. Previous studies have mostly used linear relations between variables and THM concentration, but also computational modelling, mechanistic and data driven models [2, 3]. Even though, there are still challenges to beat: most studies use a small database and laboratory-scale for model building, forgetting the impact of network pipelines and season. In addition, significant variables for DBPs’ formation such as retention time are most of the time neglected due to its difficulty to measure. Finally, THMs are not the only DBPs generated from disinfection or even the most toxic: other DBPs must be studied, and their formation pathways along the network investigated. In this study, data from a full-scale distribution network was used: online sensors and sampling campaigns. To include hydraulic conditions as retention time, EPANET software and R programming are used to simulate the network. Different models, mechanistic and data driven, have been used to estimate the chlorine decay and DBP formation within the network. Results of the calibration and validation of these models and the conclusions obtained are presented.Peer ReviewedPostprint (published version

Calidad del agua, contexto social e higiene en comunidades rurales alto-andinas de Huancavelica (Perú)

En Perú un 50.35% (Año 2017) de la población total dispone de acceso a agua para el consumo humano gestionada de forma segura, mientras que, en el sector rural, este indicador llega solo al 20.75% (JMP, 2019). Por otro lado, en el Departamento de Huancavelica la prevalencia de enfermedades diarreicas agudas en niños (as) menores de 5 años, se encuentran entre el 10-12.8%. Mientras que la prevalencia de anemia en niños (as) de 6-59 meses de edad, se encuentra entre el 40-49% (ENDES, 2018). Siendo muchos de ellos atribuibles a la falta de condiciones adecuadas de servicios de Agua, Saneamiento e Higiene (ASH). En este contexto, en el 2019 se llevó a cabo la primera fase del proyecto, entre la Universidad Nacional de Huancavelica (UNH) y Centro de Cooperación para el Desarrollo (CCD) de la Universidad Politécnica de Cataluña (UPC), con la finalidad de mejorar la gestión del agua y fortalecer las capacidades técnicas de los operadores de agua en comunidades rurales alto-andinas de Huancavelica (Perú). La primera fase de este proyecto tuvo como objetivo hacer un estudio del contexto social, higiene y calidad del agua en cinco comunidades rurales de la Provincia y departamento de Huancavelica, así como una evaluación de los sistemas de cloración y protocolos utilizados. Los resultados de este estudio concluyeron con la necesidad de capacitar a los representantes de las Juntas Administradoras de Servicios de Saneamiento (JASS) para una correcta gestión de los diferentes sistemas de agua, establecimiento de protocolos de cloración adecuados, dotación de insumos (cloro, detergentes) a las comunidades rurales, así como mantenimiento/limpieza de manantiales, reservorios y redes de distribución. Se detectó también falta de acceso a jabón en gran parte de las Instituciones Educativas y una muy baja participación de la mujer en las JASS.Peer ReviewedPostprint (author's final draft

Chlorine concentration modelling and supervision in water distribution systems

The quality of the drinking water distributed through the networks has become the main concern of most operators. This work focuses on one of the most important variables of the drinking water distribution networks (WDN) that use disinfection, chlorine. This powerful disinfectant must be dosed carefully in order to reduce disinfection byproducts (DBPs). The literature demonstrates researchers’ interest in modelling chlorine decay and using several different approaches. Nevertheless, the full-scale application of these models is far from being a reality in the supervision of water distribution networks. This paper combines the use of validated chlorine prediction models with an intensive study of a large amount of data and its influence on the model’s parameters. These parameters are estimated and validated using data coming from the Supervisory Control and Data Acquisition (SCADA) software, a full-scale water distribution system, and using off-line analytics. The result is a powerful methodology for calibrating a chlorine decay model on-line which coherently evolves over time along with the significant variables that influence it.Peer ReviewedPostprint (author's final draft