Ulseth estimates thousands of fish, some weighing 20 to 30 pounds, are dead along a roughly 20-mile stretch of river on the western border of Fulton County.<\/p>\n
Published May 26, 2026 10:26 AM EDT\t\t\t\t\t<\/p>\n
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Updated May 26, 2026 10:26 AM EDT\n\t\t<\/p>\n
\n\tJason Ulseth gives a boat tour of the Chattahoochee River in Atlanta in April 2025. (Photo Credit: Erik S Lesser\/EPA-EFE\/Shutterstock via CNN Newsource)\n<\/p>\n
\n\t(CNN) \u2014\u00a0A massive fish kill on the Chattahoochee River west of Atlanta was reported Friday by environmental protection non-profit, Chattahoochee Riverkeeper. Chattahoochee Riverkeeper executive director Jason Ulseth told CNN he discovered the dead fish when he embarked on a river patrol Friday morning.\n<\/p>\n
\n\tUlseth estimates thousands of fish, some weighing 20 to 30 pounds, are dead along a roughly 20-mile stretch of river on the western border of Fulton County. He found spotted bass, catfish, carp, shad and striped bass \u2014 floating, strewn along banks and caught in debris piles and low-hanging tree branches.\n<\/p>\n
\n\tAn unidentified, foul-smelling black substance has also coated the river banks, according to Ulseth.\n<\/p>\n
\n\t\u201cTo see everything dead was just catastrophic,\u201d Ulseth said.\n<\/p>\n
\n\tThe die-off followed an intense thunderstorm that dumped three inches of rain per hour on the Atlanta metro area Wednesday, which also\u00a0flooded area streets resulting in flash flooding<\/a>.\n<\/p>\n \n\tInvestigations into the cause of the fish kill are ongoing by Chattahoochee Riverkeeper and the City of Atlanta\u2019s Department of Watershed Management. Both entities believe drought and heat played a role in the die-off.\n<\/p>\n \n\tDue to prolonged drought, the river was running very low when the storm arrived. There simply wasn\u2019t enough cool water to moderate the influx of significantly warmer stormwater, heated by urban infrastructure.\n<\/p>\n \n\t\u201cOnce the heavy rainfall event hit the downtown urban core, the river had little buffer capacity to absorb nutrients and thermal loads. The flow on the Chattahoochee River was very low, while the urban streams were very high flowing into the river. The elevated temperature and time of day may have contributed to the creation of additional thermal load and stress on aquatic life,\u201d Lena Hardy, a spokesperson for the City of Atlanta Department of Watershed Management, told CNN.\n<\/p>\n \n\tBut Chattahoochee Riverkeeper believes stormwater and sewage discharge from an underground tunnel system built to hold excess wastewater likely also contributed to the incident.\n<\/p>\n \n\t\u201cAt this time, Chattahoochee Riverkeeper believes low flows in the river due to drought, massive polluted stormwater flows from Peachtree Creek, a discharge of untreated combined sewage from the City of Atlanta into Peachtree Creek, and additional treated discharges from wastewater facilities into the Chattahoochee River created the conditions for the fish kill,\u201d\u00a0the organization said in a Saturday press release<\/a>.\n<\/p>\n \n\tUlseth said he found condoms, menstrual products and wet wipes in the river, which he says strongly suggest sewage contamination. Other litter, more consistent with stormwater flows, have also accumulated with the dead fish, he said.\n<\/p>\n \n\tMoreover, the affected stretch of river begins where an overflow structure associated with the tunnel system drains into the river, according to Ulseth.\n<\/p>\n \n\tHardy said that, as of Monday, \u201cpreliminary water quality data indicates the tunnel system operated as designed and within permitted water quality standards. However, all laboratory tests have not been completed, and DWM is still investigating the impact to the river and the relationship to the fish die off.\u201d\n<\/p>\n \n\tUlseth says litigation over sewage contamination in the Chattahoochee River dates back to the 1990s and is ongoing.\n<\/p>\n \n\tCNN also reached out Georgia Environmental Protection Division and Georgia Department of Natural Resources. The natural resource agency directed CNN to the Georgia Environmental Protection Division.\n<\/p>\n \n\tThe-CNN-Wire\u2122 & \u00a9 2026 Cable News Network, Inc., a Warner Bros. Discovery Company. All rights reserved.\n<\/p>\n