FULTON COUNTY, Ga. (CW69 News at 10) —  A new phase of the Big Creek Wastewater Expansion Project started this month in Fulton County. Workers have now started construction on the $320 million project about 2.5 years after initiating the design phase in Spring 2018.

“We believe this is the largest single infrastructure project that Fulton County has ever done from a cost-value standpoint,” said Fulton County Director of Public Works David Clark. He says they started clearing the site at the plant on Marietta Highway last fall, and they completed the design process in May 2020.

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“They had to move about 175,000 cubic yards of dirt in order to prepare for the expansion,” said Clark, describing that amount as the equivalent of about 11,000 dump trucks. He said there are 50 to 100 people working onsite at any given time.

According to officials, the last expansion was completed in 1992, increasing the wastewater treatment capacity to 24 million gallons a day. The 50-year-old plant now treats about 22 million gallons of wastewater per day, so more capacity is needed. Clark said it’s the result of significant population growth in the 70-mile service area, which includes parts of Cobb and Forsyth Counties.

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“We’re just about at the point where we can’t allow for anymore wastewater to come into the plant to be treated. So, therefore, we’re increasing it, expanding it to 32 million gallons a day,” he said.

The project is funded through bonds obtained by the county, and residents are paying for them through their water and sewer taxes.

“If we don’t stay ahead of the development, then we could actually be in a place where a moratorium of the development might occur, and other economic issues are going to become a part of it,” Clark said.

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The construction is expected to take 46 months, ending in Summer 2024. Once it is completed, officials say the expanded capacity should last for another 30 years.