The inversion of resistivity data produces smoothed results due to regularization. This potentially adds difficulty into interpretations if regions within the subsurface are defined by sharp boundaries. This problem is improved by incorporating prior information into the inversion. Prior information applied to such inversions have recently been obtained from other geophysical datasets, such as seismic, well-logs, or borehole-based GPR. I propose to incorporate data obtained from surface-based GPR. This approach will achieve higher spatial resolutions, improved accuracy resistivity values, provide more realistic models, and will be especially useful for near-surface geophysical investigations. The Boise Hydrogeophysical Research Site (BHRS) located in Boise, Idaho, is a well known area due to several previous studies at the site, and will be used to test the performance of this inversion method. An application study will also be conducted at a research site near the Bogus Basin recreational ski resort, located just outside of Boise, Idaho, where the inverted results will be used to estimate lateral variations in soil moisture of a hill slope during melt events of an overlying snowpack.