SAVANNAH, Ga. (WSAV) – A recent report indicates a multi-million dollar dissolved oxygen system will be successful in replacing lost oxygen in the Savannah harbor due to the current deepening project.
The U.S. Army Corps of Engineers has been testing the system, which has what are called Speece cones at two locations — Hutchinson Island and Effingham County. The system captures river water inside the cones, adds fresh oxygen and then disperses the oxygen-rich water back into the river.
Environmental groups sued when SHEP (Savannah Harbor Expansion Project) was first proposed, charging that fish would be harmed by the dredging operations in the river. That’s because dredging allows more saltwater and chlorides to get into the water, which lowers the oxygen level.
Billie Birdwell, from the Savannah District of the Corps of Engineers, says the report indicates the system can keep oxygen levels the same as they were before dredging.
“That way the fish we already knew were going upstream and doing just fine will continue to go upstream and do just fine,” said Birdwell.
The Speece cones have never been used for such a large-scale project — a fact that led environmental groups to be concerned.
“But we thought it was really important to make sure that before we started digging, that we actually ran these tests,” said Savannah Riverkeeper Tonya Bonitatibus.
The Corps says its report indicates the system can place the required 40,000 pounds of pure oxygen into the river per day.
“A settlement agreement said that we would test this injection system through the summer, which we did last year, and that we would file the report,” said Birdwell.
Testing in the summer was important because hotter water temperatures are what affect fish the most.
“The full impact has not been seen yet, so the testing is a good indicator that we’re headed in a positive direction,” said Bonitatibus. “The important part is when all of this impact is realized after full dredging, will those (cones) able to keep up with it?”
The Corps has confidence in the system, which was not cheap.
“It costs about $2 million a year to operate, and we estimate it cost approximately $100 millIon to install,” said Birdwell.
Birdwell says they’ll use the system this summer as they move forward
“We’re moving forward,” he said. “This harbor is finally going to be deepened.”