Abstract
This work establishes a semi-automatic methodology to define and evaluate the Environmental Protection Areas (EPA),
in the Paraíba River Basin, Brazil, taking account the land use and the water quality. The development of this work
started from the water capitation point of Guaratingueta city located on the stream that runs through the city. From
ASTER GDEM data the drainage network and the basin catchment was automatically extracted. Landsat images for the
dates of 1989, 2001 and 2014 were digitally classified and the land uses were mapped, considering the area of permanent
protection (APP) for drainage, respecting the limits indicated by Brazilian forest code. Scenes from the RapidEye
satellite were used to answer questions of classification, due to good image definition. The study showed that in 1989,
the total area classified as APP, 37.59% were anthropized, reaching 37.98% in 2001 and 36.98% in 2014. In a few years
it was possible to associate data from water quality, measured directly at the capitation. In 2001 the water quality data
showed that the intensive use of fertilizers drained into the Guaratingueta stream by rice paddies was seriously affecting
the water supply of the municipality. In 2008 measures for water quality at the capitation point showed that the water
resources were still impacted by agricultural activities from the rice fields. So, this work indicates the need for
revitalization of the APP inside the EPA Guaratingueta in order to meet the law, protect watersheds and also avoid large
investments in water treatment arriving for public consumption.
