Augusta Utilities let two fire hydrants run into storm drains through the weekend, closing the drains' gate into the river to divert the flow back to Augusta Canal's third level, Director Tom Wiedmeier said.
The treatment comes in light of a recent Augusta Chronicle analysis of samples taken from 50 sites in Richmond, Columbia and Aiken counties that found high levels of fecal coliform, a bacteria found in animal or human waste, in the Olde Town storm drain and elsewhere.
It also anticipates the Sept. 26 Iron Man Triathlon, when more than 3,000 athletes will swim a 1.2-mile course that begins at Fifth Street, just upstream from Olde Town.
"The hydrants were running to flush a line at Second Street that has a gate on it that's closed in the event of a flood," Wiedmeier said.
"The line also goes all the way back down across Second Street and eventually winds up in the third level of the canal."
Sending the water to the canal's third level, which flows to Beaver Dam Creek, lessens the chance of humans coming into contact with the bacteria, he said.
"The only reason we're doing it during these particular times is that there's far less chance of public contact there," Wiedmeier said.
In the 1980s, the city tried to separate its sanitary sewer lines from its storm sewer drains, which traditionally had flowed sewage and stormwater runoff together into the river, but officials acknowledge that the process was incomplete.
By pumping smoke through the lines, the department traced one source of the coliform to an East Telfair Street apartment complex whose sewer line was seeping into a storm drain line.
But the elevated levels remain, and the department thinks they may be coming from one or more of the older houses located within a block of Second Street, Wiedmeier said.
"We think it has to be individual houses tied onto the storm sewer," he said.