Reclaimed water data center cooling: what Google does in Georgia

A reclaimed water data center cools its servers with treated wastewater instead of drinking water. Google’s Douglas County, Georgia site is a long running example.

The Georgia site

The Douglas County data center opened in 2007 and first used drinking water for cooling. A 2012 trade report says it then switched, diverting about 30 percent of the treated wastewater from a nearby plant, treating it again on site and using it in the cooling towers.

What Google says

Google says the site recycles local municipal wastewater that would otherwise go to the Chattahoochee River, and water that is not evaporated is treated and returned. The company also says it uses reclaimed or non-potable water at more than 25 percent of its campuses. Those are company claims.

The honest limits

Evaporating reclaimed water still removes it from the local system, even though it is not drinking water. Reclaimed supply only exists near a treatment plant, and a utility may have its own uses for it. The 2012 report is old, and I could not confirm current volumes.

A measurement gap

Researchers note that common WUE protocols do not separate reclaimed from potable water, so a good score does not tell you the source.

What this means for water planners

Treated wastewater is a real option when a plant sits close to the campus. The utility, the operator and the regulator have to agree on supply, treatment and discharge, and the deal should be written down in plain terms.

Communities can ask whether the reclaimed supply has other uses, such as irrigation or industry, before it is committed.

The takeaway

Using non-drinking water is a sensible step in water stressed areas. Ask each operator for the source and the volume, not just the ratio.

Every figure in this article comes from the sources listed below, and where a number is company reported we say so. Our Eco Tools page has a water estimator if you want to size up a project yourself. If you spot a mistake, tell us and we will fix it.

Sources: DatacenterDynamics on Google Georgia; Google on cooling. Figures marked as company reported come from the company itself.