Domestic wastewater from homes without sewerage is discharged directly into the ground, rivers or streams, which generates health and pollution problems. Septic tanks are used as an on-site treatment by a significant fraction of the world's population. This study aimed to evaluate the efficiency of domestic wastewater treatment using septic tanks with baffles implemented in rural households. The septic tanks were built and evaluated as part of a research project, focused on decentralized domestic wastewater treatment systems at the rural level. The septic tanks operated with detention times of 4.44; 2.67 and 1.90 days. The data was obtained through five monitoring campaigns with a fortnightly frequency, taking water samples at the entrance and exit of each septic tank. After sample collection, concentration levels of BOD5, COD, total suspended solids (TSS), nitrates, and phosphates were ...

This study assessed a high Andean lake’s trophic state and water quality using methodologies with eutrophication and water quality indexes. Water samples were collected at six points in the lake, with a monthly frequency, for three winter and three summer months. Dissolved oxygen, pH, phosphates, nitrates, transparency, chlorophyll-a, fecal coliforms, biological oxygen demand (BOD), temperature, and turbidity were determined at each point. The trophic state of the lake was categorized by applying the Organization for Economic Cooperation and Development (OECD) eutrophication index, Carlson’s trophic state index (CTSI) and trophic index (TRIX). In addition, National Sanitation Foundation water quality index (NSF-WQI), Canadian Water Quality Index (CCME-WQI) and Oregon Water Quality Index (OWQI) were used to evaluate water quality. Results indicated that the lake had a high level of eu...