Evaluación de las plantas de depuración de agua residual de las Comunidades de Soldados y Churuguzo, Cantón Cuenca, Azuay

Abstract

An evaluation of the performance of two wastewater treatment plants (WWTP’s) was conducted. The WWTP’s are located in Soldados and Churuguzo, both in the rural area of theCuenca canton, province of Azuay, Ecuador. BothWWTP’s are composed by a septic tank followed by a constructed wetland as secondary treatment. This research covered the following steps: (i) characterization of the population served and the sewers connected to the WWTP’s; (ii) the condition of the physical infrastructure of the WWTP’s and a description of the emergent works needed; (iii) characterization of the physical, chemical and biological processes occurring in each treatment unit; (iv) evaluation of the removal efficiency of the major pollutants by measurements on the influent and the effluent. The works executed include field and laboratory activities in collaboration with ETAPA EP and the Laboratorio de Sanitaria, Facultad de Ingeniería, Universidad de Cuenca. Besides, a literature review about wastewatertreatment technologies, specifically the ones present in the WWTP’s under study was performed. It was observed that both sewerage networkconnected to the WWTP’s have a high percentage of illicit water from irrigation and infiltration. Furthermore, despite the limitations found in the plant design, operation and maintenance, the built infrastructurein both cases reaches an acceptable percentage of pollutant removal, except for the coliforms. The latter suggests that the treatment systemsare operating wellconsidering the environment protection; however, not adequate for the public health; so, it is needed a greater effort in the design and maintenance stages of the WWTP’sto guarantee asound system performance.