This work proposes a method for detecting variation in water front between low and high tide conditions in the Gulf of Mexico area using high resolution satellite imagery. Radarsat 1, Landsat images and aerial photography from the Apalachicola region in Florida were used to test the proposed algorithm. A change detection approach was implemented through the analysis of RGB false color composites. In order to alleviate the effect of the inherent speckle in the SAR images ancillary data were used. The flood prone area was a priori delineated through the determination of lower and higher water contour lines with Landsat images and digital elevation model. This technique improved the performance of the proposed algorithm with respect to the detection technique using the entire scene.