O sistema de abastecimento de água de Natal: uma análise territorial dos riscos de colapso hídrico

Abstract

Human supply is one of the essential activities for the development of society, since commercial, industrial, residential actions, among others, require largescale water consumption. In urban centers, where the demand for consumption tends to be higher, there is a need for water supply systems to be technically well structured, so that they can serve the population effectively and minimize the risks of water collapse. Several Brazilian cities in recent years have experienced water shortages or collapse, such as Natal, capital of the state of Rio Grande do Norte, which has faced a series of problems in its water supply system. The analysis of this context took into account two sets of categories: the categories of land use by Santos (1985; 1994); and the Thywissen collapse risk categories (2006). From this perspective, the objective was defined to analyze the relationship between the use of the territory and the risk of water collapse in the Natal water supply system. To achieve this objective, a series of methodological procedures were adopted, such as the articulation of the categories of land use and risk analysis; the definition of analysis levels, study variables and weighting scales; database management in a matrix perspective (lines x columns); the mathematicalstatistical formulation of the Risk Index of Collapse of the Water Supply System (IRCSAA) of Natal; as well as the application of the Geographic Information System in the context of IRCSAA, to generate risk maps. Of the 26 supply sectors, 18 had a medium risk of water collapse; and 8, high risk. Most of the sectors that are at high risk of collapse are in the North subsystem (areas covered by the R8 reservoir; the Redinha water intake (P 45); the Brasil Novo intake (P 31); the Brasil Novo intake (P23); the Jardim Brasil and the Alvorada Collection); while only 02 sectors of the South subsystem presented a high risk of collapse (areas of reservoirs R9 and R13). To reduce these risks, it is necessary to implement integrated management plans for surface water sources; expansion of the sanitary sewage network; improvement of technical structures; and creation of a risk contingency plan for the supply system.