This repair project involved the excavation of waste slide materials on top of inverted siphon pipe and removal and replacement of top 120 degrees of cast-in-place concrete section of pipe, for an approximate distance of 70 feet. Inside diameter 9 feet, at a slope of 77 vertical feet for each horizontal foot of run, with a wall thickness of 10 inches. Installed MSE retaining walls with micro pile foundations to provide cover for siphon pipe.