This trail traverses the top of the Niagara River bank, extending from Broderick Park to south of the International Bridge. This section of the Shoreline Trail experienced erosion from the Niagara River along Unity Island, and heavy armor stone had been placed to reduce the erosion. While much of the armor stone remained on the river bank, some of the fine soil and aggregate between the armor stone was eroded away, leaving voids between the armor and the trail above. The loss of the fine soil and aggregate caused undermining of the trail. Stabilizing the ground beneath the river side of the trail was required before the trail could be reconstructed.

McMahon & Mann developed a plan to fill the void spaces where the trail had been undermined, thereby providing support for the subgrade of the reconstructed path. Multiple aggregate gradations were required to provide support, and resist erosion. The aggregates needed to be compatible with adjacent material.