LILBURN -- On Sept. 20, construction crews and sewage plant workers were preparing to test new influent pumps that would bring sewage to the Yellow River Water Resources Facility for treatment.
The next day, they did more than test the new pumps. When rains deluged the area and the nearby river crested, the old pump station building was under water.
When the river receded about a foot from the new pump station, workers were able to turn it on and minimize the plant's sewage spill into the river.
"We are much more prepared for rainfall than we were a year ago," plant supervisor Ben Bagwell said as Water and Sewerage Authority members toured the plant Monday. "It definitely helps us."
Before construction began on the plant's expansion, Bagwell said only about 3 million gallons of sewage could be stored before treatment. With two 20-million-gallon tanks newly constructed, operators were allowed to store 36 million gallons during the September floods.
The expansion will allow the plant to treat an average of 22 million gallons a day, doubling the plant's capacity and allowing smaller, less efficient plants to close in southern Gwinnett.
The $250 million construction project began in January 2007, and about 55 to 60 percent of the project is complete, officials said.
By the end of the week, Bagwell said sewage will begin running through a brand new preliminary primary treatment building, where much of the larger particles that end up in sewage pipes, including sludge and scum, are filtered out before the water is treated.
While the construction contract concludes at the end of 2012, Bagwell said the secondary treatment facility should be complete in a year.
Michael Sullivan, the chairman of the Water and Sewerage Authority who lives very close to the plant, said nearby residents haven't been impacted by the process.
"I think it's a great neighbor," he said, amazed that operators continue to treat sewage during the construction period.
"It's amazing all the work that has been done while it's still (operating). That's some serious multitasking."
Construction is ahead of schedule for the major expansion at the Yellow River.