2025 Texas & Southeast Best Projects
Award of Merit, Water/Environment: Santee Cooper Cross and Winyah ELG Projects
Santee Cooper Cross and Winyah ELG Projects
Moncks Corner, S.C.
Award of Merit
Submitted by Stantec Consulting Services
Owner Santee Cooper
Lead Design Firm, Structural/Civil/MEP Stantec Consulting Services
GC/CM Thompson Construction Group
Technology Provider Xylem Water Solutions
The projects at the Cross and Winyah stations in South Carolina were designed to treat flue gas desulfurization effluent and meet the U.S. EPA’s 2020 effluent limitation guidelines for arsenic, selenium, mercury and nitrates. Full regulatory compliance was required by Dec. 31, 2025. To meet the stringent limits, the project team designed and constructed two similar wastewater treatment systems in parallel and on a tight schedule.
In early 2023, Santee Cooper made the decision to operate its Winyah Generating Station past the EPA’s date for cessation of coal-fired power generation. The decision doubled the scope of the project and left just over two years to engineer, procure and construct the wastewater treatment system in time to meet the compliance deadline.
Crews drove 5,090 foundation support piles and installed over 11,000 cu yd of concrete. The project also included 631 new pieces of equipment, 300 tons of structural steel and over 34,000 linear ft of new pipe. Crews installed more than two miles of underground HDPE force main piping. The path crossed a railroad in two locations and passed under existing storm drain piping. The team decided to directional bore the entire force main line, which eliminated safety concerns for open excavations and reduced the amount of erosion controls needed. The strategy ultimately saved time and costs.
Despite the tight timeline, the $305-million project was delivered on schedule and at budget.
