The purpose of this study is to document the performance and effectiveness of two mitigation techniques, geosynthetic reinforced fill and flowable fill, installed behind four Wisconsin bridges. Two of the bridges (Hemlock and Cranberry bridges) are founded on granular soil foundations that are relatively incompressible. The other two bridges (Western Avenue and Beloit bridges) are founded on compressible foundations. This was done to investigate the  effectiveness of the chosen mitigation techniques (geosynthetic-reinforced fill and flowable fill) in reducing approach settlements for two different foundation conditions: incompressible and compressible. There was no attempt to reduce the consolidation of the compressible foundation soils.