Officials are investigating a pollution incident that occurred earlier this month a few miles south of downtown Atlanta, which local water advocates say sent toxins into a tributary of the South River and killed fish for miles downstream.
The pollution was discovered Sept. 6 by a group of Georgia State University students conducting regularly scheduled water sampling, when they noticed black, smoky water flowing in the river as it crosses under Forrest Park Road in south Fulton County, said Sarah H. Ledford, a Georgia State professor of geosciences.
Lab analysis of the samples collected revealed E. coli concentrations thousands of times higher than the federal Clean Water Act allows, Ledford said. Data from U.S. Geological Survey water gauges stationed in the same part of the river and farther downstream show dissolved oxygen values plummeted to around 2 milligrams per liter from Sept. 6-7 . Oxygen concentrations that low are known to trigger fish kills.