A qualitative analysis on implementing the sewer system for an indigenous village in the influence area of Belo Monte Hydroelectric Plant (Brazil)

In this article, the project and implementation of the sewer system in the Paquiçamba Village, as a condition for environmental licensing, was investigated. This village is surrounded by the influence of the Belo Monte Hydroelectric Plant (Brazil). This research aimed to characterize the context of ethnodevelopment, thus recognizing the social participation of the indigenous people. The research within a qualitative approach between 2009 and 2018 was based on primary data sources (through structured interviews) and secondary data (electronic files related to the environmental licensing). Data were analysed according to descriptive, focused and selective observations until reaching theoretical saturation. The organization of the data was followed by the organization of the themes, which formed a spiral of interconnected activities based on Creswell's proposal (2014). It was detected that indigenous involvement occurred at some moments in the elaboration of the sewage system project. The maintenance of ancestral habits in the disposal of excreta by a portion of the indigenous people, even with the sewage system in place, makes it essential to broaden the debate on the projects proposed on the environmental licensing processes. The Indigenous can not only have a consultative role, but assume a deliberative participation, being protagonists in conducting their own development.

MODELLING AND MONITORING OF STRUCTURAL SAFETY OF UNIQUE UNDERGROUND STRUCTURES OF THE SEWAGE SYSTEM OF LARGE CITIES IN DIFFICULT GROUND CONDITIONS

Anthropogenic and dynamic impacts on facilities of underground urban infrastructure increase at intensive development of megacities. The unique long-operating underground structures of sewage system require special protection against anthropogenic influence as their wear degree in difficult soil conditions reaches 70 % and more. Therefore, providing structural (mechanical) safety of underground structures of excessive level of danger and responsibility defines sustainable operation and future development of geotechnical infrastructure of the megacity in general. Long-term studying dynamics of changes of technical state of underground sewage structures of the megacity, long operating (for more than 70 years) in soft soils, allowed establishing regularities of influence of intensive anthropogenic and dynamic impacts on this process. For the first time, based on developed continuous models of defective structures potentially dangerous sections have been identified, they are subjected to manifestation of critical failures; ways of their correction are presented. Numerical simulation has defined borders of defectless joint operation of the system “target area - geomassif - underground structure". Scientific substantiation of boundaries of areas with potentially dangerous sections of underground sewage facilities with account of external anthropogenic and dynamic impacts constitutes the basis for elaborating regulations on safe development of geotechnical infrastructure of the historical area of St. Petersburg. The proposed methods of monitoring and protection of geotechnical infrastructure have been successfully used for many years by St. Petersburg Vodokanal in areas of influence of anthropogenic factors and objects under construction on underground structures, they ensure an optimal combination of sustainable operation and development of geotechnical infrastructures of megacities.

Charles Liernurs pneumatische riool en het besturen van bodems

Charles Liernur’s Pneumatic Sewage System and the Governing of Soils This article interrogates the epistemological conditions of Charles Liernur’s pneumatic sewage system in order to shed light on the changing relation between soils and Dutch society in the nineteenth century. The first section discusses the relation between hygienism, soil and sewage. The second section unearths how Liernur’s design related to the agricultural chemistry of Justus Liebig. Through the epistemologies and the mediating technologies that are operationalized by hygienists and chemists, soils are made governable. The final section of this article discusses the struggle to commercialise the urban waste collected by Liernur’s system, highlighting the difference between governable and governed soils.

Vulnerability of urban floods in association with the sewage system and geographical features in the Giulești – Sârbi neighborhood, Bucharest, Romania

The study aims to analyze the vulnerability of floods and their impact in the Giulești-Sârbi area, the marginal northwestern neighborhood of Bucharest. The location of the accumulation lake has hydrological importance for the studied area. The anthropogenic dam is one of the susceptible sources of floods, but the most inefficiency of the sewage system is the actual principal cause, which frequently flows back when there are significant increases in rainfall. The motivation for choosing the study is represented by the vulnerability of the Giulești-Sârbi area and by the lack of a study on flood vulnerability and frequency in the area. A questionnaire was also applied locally, some of the results being presented in this paper. The main objectives of the study refer to the spatialization at the street level of the vulnerability of floods and their following impact. It also compares the vulnerability of floods after two key periods: before and after the construction of the dam, respectively 1980 and 2020 – for the comparison and evolution of terrain changes. The problem was also analyzed by the vulnerability related to the slope, land use and geological characteristics. The results show that the Giulești-Sârbi neighborhood is still susceptible to floods. The most affected streets are those from the southeastern part of the neighborhood and punctually to the NW. On the other hand, the application of the questionnaire shows that the southernmost street (Răsadniței Street) did not register problems as often as the current hazard maps from the rowater.ro source for which the highest vulnerability was expected to show. The areas indicating problems according to the questionnaires and Romanian Waters National Administration maps largely coincide with the results of the vulnerability maps resulting in this paper. The main solution that can reduce the effect of flood vulnerability is the modernization of the sewage system.

Wastewater based surveillance system to detect SARS-CoV-2 genetic material for countries with on-site sanitation facilities: an experience from Bangladesh

The presence of SARS-CoV-2 genetic materials in wastewater has become a matter of grave for many countries of the world. Wastewater based epidemiology, in this context, emerged as an important tool in developed countries where proper sewage system is available. Due to the recent shift in the spread of the infection from urban to rural areas, it is now equally important to develop a similar mechanism for rural areas as well. Considering the urgency of the issue a study was conducted in 14 districts of Bangladesh and a total of 238 sewage samples were collected in two different periods from December 2020 to January 2021. We are the first to propose a surveillance system for both urban and rural areas where a proper sewage system is absent. Based on RT-PCR analysis of the water samples, in more than 92% of cases, we found the presence of the SARS-COV-2 gene (ORF1ab, N, and Internal Control-IC). The trend of Ct value varies for different study locations. The spread of genetic material for on-site (m = - 0.0386) sanitation system was found more prominent than that of off-site sewage system (m = 0.0105); which indicated the shift of genetic material from urban to rural areas. Wastewater samples were also measured for physicochemical parameters, including pH (6.30 - 12.50) and temperature (22.10 - 32.60)C. The highest viral titer of 1975 copy/mL in sewage sample was observed in a sample collected from the isolation ward of the SARS-COV-2 hospital. Additionally, a correlation was found between bacterial load and SARS-CoV-2 genetic materials. The results indicated the association of increased Ct values with decreasing number of patients and vice versa. The findings reported in this paper contributed to the field of wastewater-based epidemiology dealing with SARS-COV-2 surveillance for developing countries where proper sewage system is absent and highlighting some of the challenges associated with this approach in such settings. Keywords: On-site Sanitation, Off-site Sanitation, SARS-CoV-2, Genetic Materials, Developing Countries, Rural Wastewater-Based Surveillance System.