SAVANNAH, Ga. (WTOC) - The U.S. Army Corps of Engineers announced a major update on the Savannah Harbor Expansion Project.
Inner harbor deepening is set to begin at the end of next month. The Army Corps of Engineers said Thursday that the dissolved oxygen injector site on the Savannah River injected enough oxygen into the river to satisfy environmental demands.
To satisfy the terms of a settlement with an environmental group, the Corps had to inject 12,000 pounds of oxygen per day into the river for two species of Sturgeons to survive. The bottom-swimmers are critically endangered. The Army Corps said the test showed an average of 13,385 pounds per day. The oxygen injector system will run in the three hottest months of the year, when oxygen levels are normally depleted in deeper parts of the river.
“The weight of evidence in the test is overwhelming in favor of showing that we’re successful not only at putting enough oxygen in the river, but that it gets to all the right places and that it’s throughout the entire water column vertically in the water,” said Russell Wicke, a spokesman for the Army Corps of Engineers. “In most cases, we’re able to increase the oxygen to better than before. It also demonstrates the kind of control that we have over the impacts that the deepening would cause.”
This is one of the last major environmental hurdles to cross. Environmental mitigation has cost more than $500 million for this project, or about half the $1 billion cost of the dredging project, according to an Army Corps spokesman.
“Just to give you an idea, most dredging projects, about 10 percent of the cost will cover environmental mitigation,” Wicke said.
“The data-driven results of these tests point to an unmistakable conclusion: The dissolved oxygen system is a remarkable success,” said Col. Daniel Hibner, Commander of the Savannah District. “The weight of evidence is immense.”
The testing period on the systems ran from March 14 to May 12. According to a Corps spokesman, the 60-day test period involved collecting 24 million data points with an acceptance rate of 97.4 percent.
“From the very beginning my team approached this challenge with incredible energy,” Hibner said. “We take our environmental stewardship very seriously. My team’s solutions-based approach and initiative demonstrate that the environmental component of the deepening is just as important to us as the navigation component.”
A second oxygen injector site is being built on the river in Effingham County; construction is almost done. Another test will be done next summer with both systems online.
Outer harbor deepening from Fort Pulaski to 19 miles into the Atlantic was completed in March 2018. The inner harbor dredging deepens the river from 42 feet to 47 feet. A spokesman for the Army Corps says the project will have a net benefit of $282 million annually.
An on-time completion in early 2022 will depend on the federal and state funding for the project. The parties involved in the settlement have 30 days to review the data, and then a roughly two-week waiting period starts before deepening work can begin.