Evaluación y propuesta de rediseño de la planta de tratamiento de aguas residuales de la comunidad de Churuguzo, parroquia Tarqui, cantón Cuenca, provincia del Azuay

Abstract

The wastewater treatment is a topic of high relevancebecauseof the direct implications on the public and human dignity. The Municipal Public Institution in charge of the telecommunications, drinking water, sewerage and sanitation in Cuenca (ETAPA EP) has been a pioneer in the implementation of both conventional and decentralized systems of wastewater treatment in the country.However, once the systems are implemented, they cannot operate and maintain by themselves;the deterioration begins and therefore, a corrective measures became crucial to keep the efficiency of the systems. This study focuses in the evaluation and proposal of redesign of the decentralized system located in the community of Churuguzo, Tarqui in Cuenca canton.Initially an analysis of previous studies of this facility was performed, and this was complemented with inflow wastewater characterizations.Currently the plant has a septic tank and two subsurface horizontal flowwetlands. Based on anexhaustive review of technical literature, the following redesign alternatives were proposedas the main treatment unit: i) Reciprocating Wetlands, ii) Recirculation Packed Bed Filter, and iii) Modify the existing Wetlands. Once the corresponding designs were elaborated and a technical and economic feasibility of the alternatives was analyzed, it was decided to redesign the current technology of the system:the subsurface horizontal flow constructed wetlands, applying the design methodology proposed by Kadlec& Knight (1996).Additionally,based on the flow and pollutant loads, the pretreatment structures, the septic tank and the pipelines were redesigned. As part of the final design, a proposal for the Operation and Maintenance of the system is also included.