Digitally processed satellite data as a tool in detecting potential groundwater flow systems

Recent hydrologic research provides support for the regional groundwater flow systems concept. The fundamental unit of such a concept is a vertical section in which three groundwater regions are distinguished, namely: recharge, transition, and discharge regions. Simulation of regional groundwater flow models has been devised using this concept. This paper presents an investigation into the use of digital satellite data as a tool in identifying the potential of groundwater flow system areas. Digital radiance data collected by LANDSAT over Big Creek and Big Otter Creek basins in southern Ontario, Canada, have been utilized to delineate the principal groundwater regimes according to the proximity of the water table to the surface, i.e. discharge, recharge, and transition areas. During the spring, the modulating influence of ground water on the near-surface temperature enables such a classification to be performed using only the near-infrared energy band of the satellite. Such classification is directly comparable with thermal data collected by aircraft overflights of the watersheds. During the summer months, however, the presence of phreatophytic vegetation throughout the watershed requires that the visible energy band data be used in conjunction with the near-infrared data to effect such a classification scheme. The location of such groundwater flow systems provides valuable input to the hydrological modeling, the selection of sites for solid waste disposal and non-point-source modeling.