Application of Remote Sensing to Environmental Monitoring: A Case Study of the 1996 Saguenay Flood in Québec

Remote sensing has been used widely for monitoring natural resources over large territories. Recently, with advances in sensor technology and computation power, application of remote sensing has been extended to monitoring local situations that have been traditionally served by black and white survey aerial photographs. In 1996, after the flood in the Saguenay region, the Canada Centre for Remote Sensing mobilized a team to study the application of advanced remote sensing technology to assist the rehabilitation efforts by various groups and governments. Satellite and airborne sensors, including Landsat Thematic Mapper (TM), SPOT Haute Résolution Visible (HRV), Radarsat Synthetic Aperture Radar (SAR) imagery and multispectral airborne videography, were acquired after the flood in the Saguenay region. The black and white aerial photographs acquired at the same time as the videography were used as a visual reference for the study. The images were analyzed and interpreted with the assistance of scientists from the Geological Survey of Canada. This paper summarizes the flood information provided by the different datasets, moving from a regional to a local scale. It also discusses issues involved in flood monitoring and compares high resolution videography with optical and microwave satellite sensors.