A large number of dead fish in the Chattahoochee River west of Atlanta were reported Friday by the environmental nonprofit Chattahoochee Riverkeeper. Chattahoochee River Conservator Executive Director Jason Ulseth told CNN he discovered the dead fish while out on patrol in the river Friday morning.
Ulses estimates thousands of fish, some weighing 20 to 30 pounds, are dead along about 20 miles of the river on the western border of Fulton County. He found spotted bass, catfish, carp, shad, and striped bass floating, scattered along the shore, or caught in debris piles and low-hanging tree branches.
Urses said an unidentified, foul-smelling black substance was also covering the riverbank.
“It was just devastating to see everything dead,” Urseth said.
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The deaths followed a severe thunderstorm that dumped 3 inches of rain per hour in the Atlanta metropolitan area on Wednesday, flooding area roads and causing flash flooding.
An investigation into the cause of the fish death is ongoing by Chattahoochee River management and the City of Atlanta Watershed Management Authority. Both organizations believe that drought and heat contributed to the death toll.
Due to a prolonged drought, river levels were very low when the storm arrived. There just wasn’t enough cold water to buffer the much warmer influx of rainwater that was heated by city infrastructure.
“When heavy rains hit the downtown urban core, rivers had little buffering capacity to absorb nutrients and heat loads. Flows in the Chattahoochee River were very low, while urban streams had very high flows into the river. Rising temperatures and times of day likely contributed to the creation of additional heat loads and stress on aquatic life,” Lena Hardy, spokesperson for the Atlanta Watershed Management Authority, told CNN.
But Chattahoochee River managers believe that stormwater and sewage discharge from an underground tunnel system built to store excess wastewater likely also contributed to the accident.
“At this time, Chattahoochee River Management believes that reduced river flows due to drought, large amounts of contaminated stormwater flow from Peachtree Creek, untreated combined sewage discharges from the City of Atlanta to Peachtree Creek, and additional treated discharges from wastewater facilities to the Chattahoochee River created the conditions for the fish kill,” the organization said in a press release Saturday.
Urseth said she found condoms, menstrual products and wet wipes in the river, which she said were a strong indication of sewage contamination. Other debris, more consistent with stormwater runoff, is also accumulating along with dead fish, he said.
Additionally, Urses said the affected stretch of the river begins where the overflow structures associated with the tunnel system flow into the river.
As of Monday, Hardy said, “Preliminary water quality data indicates the tunnel system is operating as designed and within permitted water quality standards. However, all laboratory testing has not been completed and DWM is still investigating the relationship between impacts to the river and fish extinctions.”
Ulseth said lawsuits over sewage pollution in the Chattahoochee River date back to the 1990s and are still ongoing.
CNN has also reached out to the Georgia Department of Environmental Protection and the Georgia Department of Natural Resources. The Natural Resources Agency directed CNN to notify the Georgia Department of Environmental Protection.
