Water scarcity in Brazilian metropolitan regions has been aggravated by the characteristics of its own development. The disrupted urban expansion in watersheds, along with the lack of infrastructure for wastewater collection and treatment, has contributed to the degradation of water sources used for public supply. This is the reason why the population is more susceptible to waterborne diseases, and to the detrimental effects of the various types of contaminants present in the water. This condition requires the improvement of water and wastewater treatment systems, by using adequate technologies in order to promote safe drinking water for the population.This study is part of the Project Water Connection from the Public Federal Ministry and aims to observe the supply systems through the concept of multiple barriers, which consists in analyzing it from the water source up to the water distribution system, seeking to ensure its quality by means of the protection of fountainheads, definition of water quality standards and implementation of appropriate treatment systems; compare the process efficiency between the conventional system and the advanced systems, in order to promote the concept of best available technology; and to develop a simplified method for the characterization of water quality using control indicators. In this method, turbidity, pH, chemical toxicity, total organic carbon, electrical conductivity, enzyme inhibition potential and estrogenicity and androgenicity tests are considered, and its efficiency have been analyzed in relation to the standards of former Ministry of Health Ordinance nº. 2914 of 2011, which was repealed and incorporated in annex XX and XXI of Consolidation Ordinance nº 5 of 2017. The results obtained in this study demonstrated that water safety plans (WSP) enable better monitoring and control of treatment systems. In this way, the study and comparison of Brazilian legislation dealing with the quality of the raw water and drinking water was presented. In this analysis it was possible to verify that 40 (forty) indicators were repeated between the legislations, showing that there is no need to monitor them in both stages, in raw water and in the post-treatment. In addition, the WSP study demonstrated that the technologies used nowadays in Brazil are not efficient for removing many pollutants, such as organic and inorganic compounds, that is, there is a need to improve them. Thus, the best technologies currently used for the groups of organic and inorganic compounds, suspended solids and microorganisms were presented. Finally, the proposed control indicators are satisfactory in systems where advanced technologies are used together, demonstrating security in simplifying water quality standards.