There are 103 known data center facilities in operation in Georgia. There are another 76 either under construction or in the planning process. They are owned by 19 different companies.
Obviously for people who care about rivers, creeks and aquifers, the amount of water that’s used by data centers is a concern. Data centers in the Flint River watershed or those that will use water from the Flint River that Flint Riverkeeper is aware of include (either fully or partially in operation, under construction or proposed): two in Coweta County, two in Fayette County, one in south Fulton County, one in Henry County (with another in the ‘rumor’ category), one in Early County, one in Crisp County and four in Spalding County (which would use water from the Griffin water system that sources water from the Flint River.) Many other communities are discussing data center sites including Baker County, Bainbridge/Decatur, and Albany/Dougherty. Dozens of Georgia counties and cities have instituted moratoriums or implemented new ordinances to control data center construction including Taylor County and Pike County. In Mitchell County, there has been a rezoning for a power plant which is related to data center development in terms of grid ‘balance’ and demand.
Data centers are typically large facilities that house servers, storage and networking equipment to provide services such as cloud computing, web hosting, financial transactions, healthcare systems, research, public safety operations, artificial-intelligence platforms, and streaming services. Types of data centers include ‘enterprise’ facilities which are owned by a single organization, ‘cloud’ facilities which are operated by cloud storage and software providers, ‘colocation’ facilities which are multi-tenant merchant facilities and ‘edge’ facilities which are smaller facilities located near and either owned or leased by end-users. These basic types can also be mixed depending upon the business models selected by developers and owners.
The main thing for people to understand is that the threat to the river depends upon several things. Where the data center is located matters a lot. The exact same size data center could pose a tremendous threat in one place and not be very threatening at all in another place. If there is adequate power and water and local officials are able to control the noise, vibration, light and any potential runoff pollution from construction or operational sites, then the impact is not zero but is a whole lot less. The threats are not uniform across the landscape.
Newer data centers can be extremely large with some operational facilities exceeding 1 million square feet (around the size of 17 football fields, more than 22 acres under roof). At least one data center currently under construction in the Flint River watershed will have approximately 7 million square feet under roof, including all machinery and office space, on more than 600 acres of land, plus an ‘extension’ slated to be in excess of 300 acres. One proposed in Early County in the Chattahoochee River watershed would reach 12 million square feet in size. Data centers account for 1 to 5% of global electricity use - about 4.4% in the U.S.
In terms of water use for cooling the computer equipment, there are two basic types of data centers, those with closed loop cooling systems and those with open loop cooling systems. There are of course ‘closed’ portions of any cooling system; the nomenclature refers roughly to using a fixed volume of water repeatedly versus ‘once through.’ Open loop systems are the most inefficient in terms of water loss from our river, creek and aquifer systems. The heat exchangers lose up to 80 percent of water to evaporative loss. The water is not lost to the regional and global water cycle, but it is gone from the local natural-resource base. If the data center extracts 6 million gallons a day from the local system, it may be evaporating somewhere between 4 and 5 million gallons of water. Also, there are serious effluent concerns. What doesn’t evaporate into the sky is usually wastewater that goes into a creek or a river somewhere and it can have a high concentration of pollutants simply because whatever was already in the water, even at ‘drinkable’ levels, is magnified in the water not lost to evaporation; even if that water does not pick up anything else along the way. Water going into the open system can be good enough to drink but the concentrated wastewater can cause problems in the effluent. We’ve seen this issue in a proposed effluent permit for the data center under construction in Hampton.
Closed-loop systems are much more efficient as measured by water use. Instead of millions of gallons of water, they use tens of thousands of gallons a day. That’s a much more manageable number from a natural resources standpoint. On the lower end of that scale, it’s like the water use of two large subdivisions. But, in order to get that type of efficiency, it burns a tremendous amount of electricity, so you are literally exporting the negative effects on our resources. The water that is not used onsite is used elsewhere to generate electricity. On the average, in Georgia, about 85% of the generation capacity relies on water, and 80% on the evaporation of water. One megawatt-hour of generation requires about 750 gallons. Therefore, on average, a large data center (250MW to 750MW power demand) will use between 3.6 and 10.8 million gallons per day OFFSITE in order to generate the ELECTRICITY required by the facility. (The math of that is 250x750x24*.8, or substitute 750 for 250 to get the higher end of the estimate). In other words, this water use is massive and is on ‘someone else’s river’ if the data center is in the Flint River watershed. Typically, in Georgia the larger steam-turbine-type generation facilities can be found on the Savannah, Chattahoochee, and Ocmulgee/Altamaha river systems. Proposals for new power-plant sites are pending in several places including Mitchell County in the Flint’s watershed.
In terms of water quality, both closed-loop and open-loop cooling systems have something in common with other industries called ‘blowdown’ or ‘backwash’ or ‘descaling’ where from time to time the facility operator must flush the system with harsh chemicals because materials build up in the pipes and would otherwise make the system inefficient or inoperable. That becomes a disposal issue, so it’s critical to know where that waste is going and what it actually is. Is it going into a local municipal system and are they prepared to handle it? Or is it going into a creek and will the discharge permits be adequate to protect the receiving waters?
Also, like any large project, there are concerns about control of sediment leaving the jobsite. Uncontrolled sediment is the most common pollutant in Georgia waters and can severely negatively affect aquatic wildlife and downstream users by increasing water-treatment costs for municipal systems and degrading the use and enjoyment of creeks and rivers for public and private property owners. Clearing land, excavating and grading exposes soil and rainfall often washes it into nearby water bodies if not properly controlled. Construction sites also frequently use paints, solvents, oils and other chemicals that can enter streams through runoff which contaminates surface and groundwater. In addition, adding surfaces like roofs and roads changes natural drainage patterns and increases surface runoff that can lead to altered flow rates for streams and rivers, increasing flooding, decreasing dry-time flows, and often carrying higher loads of pollutants to bodies of water.
Stormwater issues during construction and even after construction are all about proper containment. A 300- or 600-acre data center is like having 10 to 30 big box stores being constructed at once. A lot of dirt is being moved, trees are being removed and it’s a lot to manage. After construction is over, the design of how stormwater is managed is a big deal also. There’s also typically a lot of chemicals for cleaning, fuel for backup power and other potentially hazardous liquids that must be properly contained to prevent spills and keep those pollutants from showing up in stormwater that washes off the property.
Other concerns are about how land is used. Runoff from a forest or a farm is not the same as runoff from a bunch of rooftops and parking lots. There are also concerns about how noise, vibration and lighting can affect and disrupt wildlife.
Another concern a lot of people have is the use of eminent domain – the taking of private property at a price that you don’t get to choose - for powerlines and sub-stations and those sorts of things. More than one community experiencing construction of a data center has had to endure what in our opinion is an abuse of the government’s power of eminent domain to facilitate the revenue and profitability of both that data center owner and the power company.
Flint Riverkeeper works daily to prevent damage to and restore the
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