The project, started in 2010, was needed to meet new water regulations and increase capacity at the facility. It’s the largest and most complex construction project in the authority’s history, according to General Manager Glenn Page.
Though the plant’s official treatment capacity of 72 million gallons a day remains unchanged, the extra capacity means sections of the plant can be shut down and repaired, not affecting the facility’s output.
The Acworth plant treats water from Lake Allatoona.
The project took slightly longer than the estimated 36-month schedule due to heavy rains, Page said, but it met the water authority’s deadlines.
The improvements were paid for in cash with funds from water bills, Page said.
“A substantial part of the rate people pay for drinking water is infrastructure,” he said. “It costs very little to actually treat water, but infrastructure is where a majority of our rates come from. Our obligation is to create sustainable facilities.”
Of the $90 million in improvements, about $30 million was for a new filtration system.
“We added a new treatment step to meet federal water quality requirements,” Page said.
Another segment of the project was renewing parts of the plant, some of which dated to the 1960s.
“We replaced four large concrete basins that no longer functioned as they should and the concrete was getting up in age,” Page said. “When you combine the age of the concrete with a water level that goes up and down, the concrete eventually deteriorates.”
The average customer won’t notice much of a difference, said Tim Lee, Cobb Commission chairman and a member of the water authority board, but the improvements keep the plant up to date with new regulations from the Environmental Protection Agency.
“The plant was renovated. It will be more reliable to produce clean water,” Lee said. “We will now be able to do maintenance while not reducing capacity. You’ll get the same clean water you always get, but the plant will be more efficient with better technology and we’ll be able to process it less expensively.”
The Cobb-Marietta Water Authority is the second largest provider of drinking water in Georgia. It provides water to authorities in Cobb, Cherokee, Douglas and Paulding counties, Lockheed Martin and several local cities. About 66 percent of the authority’s water is sold to Cobb County. Paulding County buys 14 percent, the city of Marietta buys 8 percent, Smyrna buys 5 percent and the rest is split among six other customers.
The authority’s website is ccmwa.org.