How much water will Effingham’s OpenAI data center need? A lot – but not on site.

When Effingham County announced plans for a massive OpenAI data center last month, area residents immediately questioned where it would get its water and how much it would need.

Data centers have a reputation as water hogs, and the Savannah area has struggled in recent years to meet growing demands for water while protecting its natural water supplies.

The “how much” question was one that even Effingham County seemed unsure of at first. In filing paperwork for a development of regional impact, the county’s senior planner wrote “no clue” in response to the question “Is sufficient water supply capacity available to serve the proposed project?”

About a week later she updated the form to indicate the data center will need 30,000 gallons of water a day. That’s low for an industrial user, about as much as 100 average households use. The authority’s website explains that quantity is for “ordinary workplace uses such as sinks, restrooms, kitchens, cleaning, and sanitation.” It does not include the one-time initial fill of the data center’s closed-loop cooling system. “That initial fill and the project’s final ongoing annual demand are still being determined through final design and water-service planning and will be disclosed when finalized,” the website states.