More than 6 million gallons of water at the U.S. National Whitewater Center started being discharged into the Catawba River on Saturday.
All of that water was dechlorinated on Friday, Mecklenburg County officials said.
The water tested positive for a brain-eating amoeba following investigations over the death last month of an 18-year-old Ohio woman. Officials believe she contracted the waterborne illness at the center when she fell out of a raft and water went up her nose.
Chlorinating the water will kill the organisms, and dechlorinating the water will assure it doesn’t hurt wildlife.
On Saturday, the Catawba Riverkeeper Foundation posted on Facebook that the water quality was excellent and chlorine levels dropped to acceptable levels, so water began to be discharged at 6:25 a.m.
Officials estimated that it will take 24 hours to complete the discharge.
The treatment included heavily chlorinating the water and then dechlorinating the water before draining it through the Whitewater Center's lower pond. That happened on Friday.
“Water is circulating and dissolved oxygen levels look good. Discharge can begin when dechlorination is complete,” Catawba Riverkeeper Sam Perkins posted on Instagram on Friday.
Rick Christenburg, a Mecklenburg County spokesman, said workers were giving extra time to allow the chlorine to naturally deplete further under the sunlight.
Officials learned around 6 p.m. Wednesday that the chlorination process was put on hold due to heat. High temperatures dissolve chlorine quickly.
“This is a natural waterway, so you want to make sure that there’s appropriate dechlorination,” Perkins said.
Mecklenburg County health officials said they are confident all of the precautions they are taking will clean the water, protect the environment and keep people safe.
Mecklenburg County Health Director Dr. Marcus Plescia said the amoeba is mainly in the sediment at the bottom of the pool at the Whitewater Center, which will be removed separately. The water will be chlorinated and dechlorinated before being drained through the Whitewater Center’s lower pond.
Plescia noted the water will be treated with 10 times the amount of chlorine needed to kill bacteria. The water needs to sit for at least two hours. Due to the heat Wednesday afternoon, the process was put on hold because the proper level could not be sustained.
The sediment, likely containing most of the amoeba, will be put out on the field above the center. Plescia said broadcasting that sediment will kill anything in it.
“We are pleased to see that the USNWC will be held to water quality standards similar to permitted discharges of wastewater treatment plants,” Perkins said in a statement.
“There is no question in my mind that this amoeba is in the Catawba River,” Plescia said of the organism living in natural water sources.
“The systems the Whitewater Center had in place were obviously not adequate to keep this amoeba away,” Plescia said. He expects the new process to be efficient.
“We feel really good about this,” Plescia said of the plan. He added that the county will monitor and test the water throughout the process.
“There will be testing at Long Creek, and there will also be testing at the Catawba River,” Lisa Corbitt, a program manager with the Mecklenburg County Health Department, said while chlorine was being pumped into lower pond at the Whitewater Center.
The health department said it want to ensure the public is safe and feels comfortable going forward before restarting the whitewater activities.
Observer staff writer Joe Maursak contributed.
WBTV is a news partner of The Charlotte Observer.