The S.C. Department of Natural Resources said Tuesday that it violated federal law while building a road in Horry County.

The agency said workers were not authorized to fill in 6 acres of wetlands on DNR property at the Lewis Ocean Bay Heritage Preserve. Agency Director John Frampton said staff thought it was following provisions of the Clean Water Act, but was wrong.

"Long story short, we had our staff working at the Lewis Ocean Bay Heritage Preserve in Horry near Myrtle Beach, and they inadvertently filled 6 acres of wetlands illegally," said Breck Carmichael, the DNR deputy director of Wildlife and Freshwater Fisheries.

The purpose of the Clean Water Act is to prevent pollution and assist improvement of wastewater treatment, while protecting the status of wetlands.

"Our DNR personnel did work that exceeded the provisions of the Clean Water Act," Frampton said. The staff assumed that it was following the best guidelines for management practices. "This assumption was an error, and they acted without proper coordination."

The DNR has authority to more than 250,000 acres of land that requires management in the land. It will work to remediate the affected wetlands at Lewis Ocean Bay Heritage Preserve, and it also will work with the Corps of Engineers to establish training for DNR staff in order to prevent further violations.