City of North Augusta

Augusta Greenway Culvert Replacement

North Augusta, SC

The North Augusta Greenway is a significant recreational trail that stands as a center piece of the City’s efforts to establish a highly regarded community quality of life environment. The trail primarily follows a late 19th Century railroad bed, elevated to accommodate the steep terrain. Heavy rainfall, localized slope failure and erosion jeopardized the integrity of the embankment forcing the City to close the trail for emergency repairs. Along with existing side slopes of 1.5:1 (H:V), alternative reconstruction methods were explored.

Benesch was contracted to provide civil design services for the reconstruction of the failed Greenway culvert and embankment. Design services included hydrologic and hydraulic analysis of the contributing drainage basin tributary to the Greenway crossing. Specific design elements unique to the project included foundation design of an 84-inch diameter concrete culvert, piping failure analysis, embankment and slope reinforcement specifications, and surface reinforcement for mitigation of erosion along slopes steeper than 2:1 (horizontal and vertical). Benesch led environmental coordination efforts with the U.S. Fish & Wildlife Department to address impacts to endangered species including the Relict Trillium.

Project highlights

  • Slope failure – closed popular pedestrian/bicycle trail
  • Old rail bed with steep side slopes
  • Endangered botanical species environment
  • Undersized culvert
  • Maintaining stormwater flows during construction
  • Minimizing construction footprint to accommodate Relict Trillium
  • Constructing a new large diameter culvert through a 30ft embankment
  • Maintaining existing sanitary sewer along embankment during construction