Spatial and temporal distribution of thermotolerant coliform in Canal de Passagem (Vitória - ES) - related to physico-chemical parameters and tide

Abstract

The Canal de Passagem (CP), Vitória - ES, is an estuarine system undergoing a process of environmental degradation due to the discharge of in natura and semi-treated sewage. The surrounding local community's use of the estuarine resources conflicts with environmental quality and this offers risks to public health. The objective of this study was 1. to evaluate the distribution of fecal coliforms in the HCP (multiple tubes method), relating it to the distribution of sources of fecal pollution, the dynamics of the tides and physico-chemical parameters, and 2. evaluate the results in the light of the limits established by Brazilian legislation to ensure the health of the users of the water whatever the use to which it is put. Samples were taken spatially and temporally, to assess the tidal cycle of the spring tide in the winter, autumn and spring seasons, and also of the neap and spring tides at two sampling events in the summer. The sanitary parameters - thermotolerant coliforms, physico-chemical, and tidal action, were considered. Meaningful correlations were found with the tidal regime. As conclusion, that the distribution of thermotolerant coliforms was related to the point sources of pollution, and the concentrations were different between spring and neap tides. This difference between tides is not taken into consideration by the Brazilian Bathing Water Legislation up to now.