Design of the Interceptor-Collector and Wastewater Treatment System for Pollution Mitigation: A Case Study

Abstract

Sustainable Development Goal 6 proposes clean water and sanitation for all. Urban parishes Veintimilla and Polibio Chávez of the Guaranda canton in Ecuador have a combined sewage network. However, they do not have an operational wastewater treatment plant (WTP), which discharges directly into the river generating significant pollution and affecting the health and well-being of the inhabitants. This work aims to design the interceptor-collector and treatment system for wastewater discharges to the Guaranda river, considering the technical aspects and sustainability criteria, contributing to the quality of life of its inhabitants, the mitigation of pollution, and the compliance with current regulations. The methodology used was: (i) review and analysis of existing information, which included topographical, social, economic, technical, and environmental restrictions; (ii) proposal and selection of alternatives; (iii) design of the selected alternative, with its respective budget, plans, and environmental analysis. The results were: (i) design errors in the existing system, industrial discharges contaminate domestic wastewater; (ii) alternatives were proposed that were assessed using the Likert scale, with number A1b being the winner; (iii) the estimated future population is 32,922 inhabitants, and the design period is 15 years, which generates a flow of 0.226 m 3 /s. The interceptor-collector consists of four bypass chambers; the WTP consists of two independent lines, each with preliminary treatment, a sand trap of 17.25 × 3.85 × 1.15 m, and percolating filters 15.4 × 7 × 2.4 m, and a clarifier of 15.4 m by 3.5 m in height. The budget is USD 941,953.49, including the environmental management plan.