Cobb County Government
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What We Do

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How we provide you with water

The Cobb County Water System partners with our wholesale provider, the Cobb County-Marietta Water Authority, in distributing clean, safe water to our customers. The Cobb County-Marietta Water Authority withdraws water from the Chattahoochee River and Allatoona Lake and purifies it. The treatment plant located on Lower Roswell Road in Marietta treats water withdrawn from the Chattahoochee River. The treatment plant located on Mars Hill Road in Acworth and treats water withdrawn from Allatoona Lake. Combined, these plants can produce up to 158 million gallons of drinking water a day.

The Cobb County Water System purchases drinking water from the Cobb County-Marietta Water Authority and distributes it to over 180,000 homes and businesses in unincorporated Cobb County and in the cities of Acworth and Kennesaw. The Cobb County Water System maintains more than 2,900 miles of water main ranging in size from 6 inches to 14 inches in diameter.

How we maintain the environment

We use water each day in homes, schools, businesses, and industry. When it leaves these places it is piped to a water reclamation facility. The Cobb County operates and maintains approximately 2,500 miles of sanitary sewer lines and 38 pump stations. These convey the used water, also known as wastewater, to a wastewater treatment plant (water reclamation facilities) where it is cleaned and treated then released back into the Chattahoochee River or Allatoona Lake. The Cobb County Water System operates and maintains four water reclamation facilities that have a combined capacity to treat up to of 128 million gallons of wastewater a day.

    Wastewater Treatment Process:
  • First, sand, dirt and large particles are removed from the incoming wastewater. The second stage is primarily a biological process. Air and special nutrients are supplied to stimulate the growth of bacteria in large basins. These bacteria actually eat most of the waste materials. The wastewater then moves through a series of filters, which remove whatever small particles are remaining. Separated solids are concentrated, de-watered and removed from the process as bio-solids. Bio-solids (sludge) are disposed of either through incineration or hauled to a landfill. In the last process, the treated wastewater receives final disinfecting which kills any remaining micro-organisms.

In addition to providing wastewater treatment for our retail customers in unincorporated Cobb County and the cities of Acworth and Kennesaw, the Cobb County Water System, through regional relationships, treats wastewater from the cities of Marietta, Smyrna, Austell, and Powder Springs and portions of the city of Atlanta and Bartow, Cherokee, Douglas, and Fulton counties.

The Cobb County Water System also protects the environment by minimizing the impact of stormwater runoff.