Proper water quality monitoring is a valuable tool for water resource management, helping to identify polluting sources and risks related to the use of water resources. One of the main types of contamination found in Brazilian water bodies is fecal contamination, which originates mainly from point source pollution through wastewater disposal. Thus, this study analyzed water quality monitoring data from the responsible environmental body (Minas Gerais Institute of Water Management, IGAM), related to the fecal contamination indicator (FCI), for the years 2000–2018. This was done for the Minas Gerais portion of the São Francisco River basin (SFRB-MG), one of the most important basins in the country. The 10 sub-basins in the area were compared using statistical tools. The work found significant differences between the sub-basins in terms of FCI concentration, highlighting the most impacted ones (SF2, SF3, and SF5) as also being the most densely populated. It is necessary to invest in sanitation measures in order to ensure that water resources are preserved, as well as to reduce the public health risks of downstream municipalities that are supplied with previously contaminated water.
Treated wastewater may affect water quality and thereby significantly alter physicochemical and biological water quality parameters. The impact of wastewater treatment plants (WWTPs) on receiving water bodies is a multivariate problem. In this study, we investigated the effect of 45 full-scale WWTPs on tropical receiving water bodies in Mato Grosso do Sul State, Brazil. Most of the Pantanal wetland area lies within Mato Grosso do Sul State, thus representing a region of great hydrological relevance. Partial least squares-discriminant analysis (PLS-DA) was employed to discriminate samples collected at four WWTPs monitoring sites: influent, final effluent, upstream, and downstream of the discharges. The model demonstrated excellent accuracy when discriminating the influent from the effluent samples, but poor accuracy when discriminating upstream and downstream samples, indicating the high dilution capacity of the receiving water bodies as a critical factor in the water resources management. The results demonstrate the great potential of the methodology for better water resources management, which can be used in even more complex WWTP databases, allowing the assessment of effluent disposals' impacts in detail. It is recommended to use this methodology in water-limited regions to determine the effect of disposals in areas with different characteristics.
In Brazil, domestic effluents represent the primary source of pressure on water resources. Water pollution can be controlled by defining, applying, and enforcing the effluent standards for wastewater discharge. Discussions are ongoing in Minas Gerais State regarding the possibility of setting a discharge standard for ammonia nitrogen in municipal wastewater, which is currently not required. However, providing technical support for decision-making is challenging because of the difficulties in accessing monitoring data from sewage treatment plants. This study aimed to analyze the monitoring data from 49 sewage treatment plants operating in Minas Gerais to offer guidance for decision making. High concentrations of ammonia nitrogen in the effluents of the treatment plants were found, reinforcing the need for better control and the adoption of more advanced technologies. Furthermore, it was observed an increase in concentrations downstream of the discharges in the receiving water bodies. Adopting a progressive and adaptable discharge standard can be a solution for better control of treatment systems.
RESUMO Apenas 30% dos municípios brasileiros apresentam tratamento de esgotos domésticos. Mesmo quando existentes, muitas estações de tratamento de esgotos têm problemas operacionais e de projeto. Neste estudo, analisou-se o desempenho operacional de dez reatores anaeróbios de manta de lodo e fluxo ascendente, seguidos ou não de pós-tratamento, localizados na bacia hidrográfica do Rio das Velhas operando em escala real, uma tecnologia bastante difundida no país. As concentrações dos esgotos tratados e as eficiências de remoção foram comparadas com valores típicos reportados na literatura, bem como os desempenhos operacionais foram comparados estatisticamente entre as estações. Os percentuais de violação aos padrões de lançamento foram calculados, e realizou-se uma análise de cluster com os dados de concentrações efluentes das dez estações de tratamento de esgotos para avaliar se as estações seriam agrupadas em função das suas configurações. Em sete das dez estações de tratamento de esgotos avaliadas (70% dos sistemas), observaram-se desempenhos inferiores ao esperado para as tecnologias empregadas, sendo os problemas operacionais e de projetos os principais fatores responsáveis pelo comportamento das estações analisadas.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.