This research aims at modeling the Good thing Basin (BCB), region Igatu, Chapada Diamantina - Bahia, especially as the physico-chemical quality of surface waters. The study area lies within the limits of the National Park of Chapada Diamantina (PNCD) and listed as a Historic, belonging to the municipality of Andaraí. Regarding the methodological procedures was used: principal components analysis (PCA), application of IQABa, spatial analysis methods by the inverse square of the distance and line graphs. The months were as follows: April, July and October 2010 and January 2011, covering twenty (20) sampling sites upstream and downstream of the BCB. The physicochemical parameters used to implement IQABa are those representing the Principal Component Analysis (PCA), which further explain how the quality of the waters of BCB: turbidity, total solids, pH, phosphate, nitrate, BOD and conductivity. From the results obtained during the sampling campaign, did the calculations Index Water Quality of Bascarán (IQABa) (Bascarán, 1979 apud Rizzi, 2001). The analysis of water quality of the BCB was performed in twenty collection points, contemplating headwater areas with little human interference, primary contact recreation, sewage discharge and areas around the mouth. It is observed that the quality of water in BCB decreases from upstream to downstream, as it is the entry of effluent generated by the anthropogenic Village Igatu. The amount of the BCB, has an area with springs, with little human interference and with good water quality, even in the dry season, reflecting the natural water of the study area. As for surface maps for the area studied, the technique called inverse square of the distance was visually satisfactory to the spatial data.Pages: 6526-653
