Problemas ambientais associados a sistemas de abastecimento de água e esgotamento sanitário: uma revisão da literatura científica e reflexões sobre a atuação do INEMA

Abstract

Although drinking water supply and sewage services are essential for sustainable development, they can also significantly impact the environmental and therefore must be regulated by governmental control agencies. In less favored regions of developing countries, such as in the Northeast of Brazil, the challenge of bringing basic sanitation services to the entire population comes with it the opportunity for expanding these services while minimizing the environmental impacts they cause, what highlights the importance of informed action by the control agencies. In the present work, I present a review of the scientific literature, inspired by the criteria of qualitative systematic reviews, aiming to exhaustively identify the environmental problems associated with the water supply and sewage systems as recognized by science. I analyzed 184 scientific documents on the topic, extracting statements about recognized problems, which inductively gave rise to 252 codes, which I also organized inductively into 14 classes of environmental problems associated with water supply and sanitation systems: climate change, electricity consumption, emission of greenhouse gases, habitat disturbance, occupation of areas by the physical structure of the system, water scarcity, water waste practices, contaminants (micropollutants, emerging pollutants, non-emergent organic pollutants, non-emergent inorganic pollutants, nutrients, pathogens and solids), consumption of chemical products, formation of toxic byproducts in the treatment processes, inadequate generation and management of effluents and waste, sewage leakage from the sewage system, inefficiency in the treatment systems (conventional technologies of treatment are not efficient for a particular type of contaminant, contaminant present in treated water or sewage, a factor that is harmful to treatment processes and contributes to the spread of antibiotic resistance), and underutilization of the system's potential. This process until the codification of the problems was systematized in a database, which is a useful tool for the technical sectors of the control agencies, service providers and holders of these basic sanitation services, since it allows them to easily detect bibliographic sources for any type of environmental problem associated with basic sanitation. Then, I identified each of the codes as associated only with water supply systems, only with sewage systems, or with both systems. I classified the problem classes inductively according to the main focus of the problem and also deductively according to its origin. I also sought to establish the strongest and most direct cause and effect relationships between classes. Then, from the scientific literature, I described each of these classes of problems, their causes and consequences. For classes that focus on basic sanitation services and focus on the opportunities that the systems offer in terms of the environment, the description was prepared separately for water supply and sewage systems. Finally, I exemplify the applicability of this product from the analysis of Institute of the Environment and Water Resources of the State of Bahia – INEMA's performance in the exercise of controlling these environmental problems. I indicate, based on my perception and the statutory attributions of each of the agency's technical directorates, which sectors act most directly in the face of each of the problems and present proposals that I consider useful to improve, by INEMA, the exercising control over environmental problems associated with basic sanitation systems. The result of this work contributes to bring scientific knowledge closer to the providers of basic sanitation services, to the regulatory and control agencies that operate in the sector and to the entities of the municipal sphere, legally owners of basic sanitation services in Brazil.