Great Falls-Dearborn Diversion Dam Bypasses

This project received the top Palmetto Award at the 2024 ACEC-SC Engineering Excellence Awards Ceremony.

S&ME provided geotechnical engineering, environmental design, permitting, and construction materials testing and support for Duke Energy’s Great Falls, South Carolina Dearborn Diversion Dam Bypasses. The project consisted of the rehabilitation of the Long Bypassed Reach Diversion Dam, Short Bypassed Reach Spillway, and Headworks Spillway. Rehabilitation of the Long Bypassed Reach Diversion Dam included notching the Dam in two locations, one to restore flows to a portion of the Catawba River that had not seen flow in over 120 years, and one to provide a recreational space and safe river access for kayakers, canoeists, and rafters. The kayak and canoe course consisted of a 1,000-foot-long switchbacked channel for water flow with concrete structures serving as deflectors, radius walls, roughness elements, and energy dissipation pools.

S&ME supported the Owner of the Project, Duke Energy, by providing the following multi-disciplined services:

  • Geotechnical Drilling and Engineering for proposed Crane Pad and Control Building Structures
  • Well Abandonment Services
  • Construction Quality Assurance and Construction Quality Control services
  • Short Bypassed Reach Pre-Construction Notification (PCN):
    • Section 401/404 Permitting; PCN Application; Protected Species;
    • Historic Properties; Tier 1 Evaluation of Dredged Materials; and
    • FEMA Flood Insurance Program Compliance.
  • Access Ramp & Drilling:
    • Geotechnical Drilling, split-spoon soil sampling, and standard penetration testing (SPT); Rock Coring for the proposed Tower Crane and Control Building structures; Soil and Rock Laboratory Testing; and
    • Geotechnical engineering to include drilled shaft skin friction design parameters for the Tower Crane and allowable bearing evaluation for the Control Building.
  • Construction Materials Testing:
    • Reinforcing Evaluations; Grout Field and Laboratory Testing; Concrete Field and Laboratory Testing; Dowel and Threaded Anchor Tensile/Pull Tests;
    • Stainless Steel Inspection to include dye penetration/liquid penetrant testing of welds and visual inspection of stainless steel welds; In-Place Density Testing and Soil Proctor Compaction Testing; and Subgrade and Soils Evaluation/Testing and Laboratory Testing.
  • S&ME supported the Contractor (Brasfield & Gorrie) by providing erosion and sedimentation control (E&SC) design and permitting for their laydown area and throughout changes on the project and increases in disturbance area.

After 120 years of dry riverbeds, the Catawba River at Great Falls now experiences a regular, natural flow of water, creating vibrant recreational, environmental, and economic impacts on the surrounding area. World-class whitewater channels and easily accessible boat-put-ins increase tourism while promoting outdoor recreation opportunities, including rafting, kayaking, paddleboarding, fishing, canoeing, biking, and hiking. Centrally located between Charlotte, NC, and Columbia, SC, the revitalized river and its surrounding access elements will draw a sizable population to bolster the Great Falls community that was so negatively impacted by the textile industry’s decline.

The restoration of water reinstates flow to two river channels that were blocked when the Great Falls Hydro Station was constructed in 1907. The restored ecology provides meaningful environmental enhancements by reinvigorating a healthy biological habitat for aquatic life and an overall contribution to clean, economical, and renewable hydropower. In the coming years, the project will continue to expand into a diverse mix of other recreation, including hiking trails and a pedestrian bridge that will connect to the new state park at Dearborn Island. S&ME’s commitment was integral to successful project completion and long-lasting impacts on the community.