The sources consist of an overflow of the water table which gives rise to the flows of water. These waters become the drainage network. Negative environmental impacts, caused on any portion of the basin, may interfere with water quantity and quality and, depending on the impact, different ways or alternatives of handling should be put in place to improve the environment. The aim of this work was to characterise the sources of the Corrego Itanguá basin, Capão Bonito, SP, Brazil, as regards the type and state of conservation, and to identify the negative environmental impacts present. As far as the type is concerned, the sources have been classified as point or diffuse, and the conservation status obtained by means of the macroscopic assessment has been ranched in optimal, good, reasonable, ruim and very poor terms. In the basin, 19 sources were identified and out of the 15 visited nine were classified as one-off while six were diffuse. As regards conservation status, two were classified as optimal, 12 as good and one as reasonable. Also from the macroscopic assessment it was observed that the presence of alien species, both animal (Sus scrofa) and plant (Pinus spp.), and the absence of native vegetation in the permanent preservation area were the most frequent negative environmental impacts. The methodology used proved to be efficient as a visual qualitative analysis of the situation of the springs and as providers of information to subsidise actions for the conservation of water in the Capão Bonito National Forest, SP, Brazil.