Data Centers and Groundwater

Part 1. Groundwater professionals help meet the challenges of data center water demands.

By William M. Alley, Ph.D., David Henrich, CWD/PI, CVCLD, and Charles Job

The rapid expansion of data centers across the United States and future ones on the horizon has captured the nation’s attention. Due to their large energy demands and often corresponding water-quantity needs, questions about groundwater availability are front and center. With that, I’m excited to share that Water Well Journal is launching a three-part series on the trending topic this month. Look for the second and third installments in the February and March issues.
—Thad Plumley, WWJ Editor

The growth of the internet, artificial intelligence, and cloud computing is resulting in rapid growth in data
centers. These warehouse-like buildings filled with long rows of computer servers are popping up across the country.

Drilling takes place for a submerged closed-loop heat exchanger system designed by Darcy Solutions in Minnesota. The system consists of 12 open hole wells, 12 inches in diameter and 580 feet deep.

Data centers in general aren’t new as they have been around for years housing infrastructure to process data that helps us function in our lives and workdays. But large hyperscale data centers are relatively new. Accompanying the rapid growth in their construction is a growing concern about the resources these installations require to operate and the long-term impact those demands might have on the surrounding areas.

Massive cooling racks of heat-producing servers have taxed water supply infrastructure and strained local water sources. Whether it be energy consumption, water consumption, or other resource pressures, data centers should be carefully planned to minimize their impacts and ensure resource sustainability.

On-site water consumption by data centers was estimated to total about 17 billion gallons nationally in 2023. Annual water usage can vary from 110 million gallons for a midsize center to 1.8 billion gallons for a large data center (Yañez-Barnuevo 2025). The latter is comparable to the water use of a medium-sized town.

Injection well piping for a 7000 gpm pump-and-injection system in Minnesota. The system consists of five supply wells and 10 injection wells. Photos courtesy David Henrich, CWD/PI, CVCLD, of Bergerson-Caswell Inc.

The U.S. Department of Energy estimates that by 2028 total annual on-site water consumption could double or even quadruple the 2023 level (Shehabi et al. 2024). The growth of AI, which uses larger and more complex chips that need far more power, heightens the concerns about cooling water demands.

Water usage by data centers depends on various factors including climate, size, and rack chip densities. With the increasing number of centers supporting AI requests, chip density is growing, leading to higher room temperatures and necessitating the use of more water chillers at the server level to maintain cool temperatures.

Early data centers were concentrated in a few areas such as northern Virginia and Santa Clara, California. Today, they are appearing across the country. Many areas with the fastest data center growth and planned capacity are water-challenged, including the San Antonio to Dallas, Texas corridor; Las Vegas, Nevada; and Phoenix, Arizona.

Because electricity is more costly for data centers than water, companies often prioritize building their facilities in places with cheap power, even if the area has limited available water resources. Data centers are also likely to spread to economically challenged rural areas, which tend to welcome data centers for their economic opportunities. Many of these areas are largely reliant on groundwater for their water supply.

Playing a Critical Role

Groundwater professionals are in a position to play critical roles in addressing water availability and the impacts of data center water use on local resources. As the number of data centers increases, it poses challenges for water resources planning and management. Data center companies want to build new facilities rapidly. Their timelines can be out of sync with the time that utilities need for planning, permitting, design, and construction of the necessary water infrastructure.

In response to the controversies over their water use, data center companies are increasingly pledging to become “water positive.” This could be achieved, in part, by greater use of treated wastewater and various means to conserve or replenish water in the area. Such projects can create opportunities for groundwater professionals. Hydrogeologists are also well versed in engaging community input, which is likely to become increasingly important in siting facilities.

Although most focus has been directed at on-site water consumption, a significant portion of data center water usage originates from the power facilities that generate their energy. The amount of added power demand by U.S. data centers in 2023 translated into about 211 billion gallons of indirect water use (Shehabi et al. 2024). Chip and server manufacturing are also significant sources of water consumption.

Data center companies rarely disclose how much water they use, creating challenges in water resources management. A 2016 report found that fewer than one-third of data center operators tracked water consumption (Heslin 2016). Water use accounting is likely to improve with increasing demands for accountability, with several states considering legislation to require data centers to report water use.

Approaches to Cooling

Data centers typically use either water- or air-based cooling systems. Tradeoffs exist between the two. Water-based systems that are reliant on evaporative cooling use less electricity, while air-based systems consume less water but require more power. As data centers face increasing cooling demands and environmental concerns, employing alternatives to evaporative cooling can lead to more sustainable and efficient operations.

Engineering alternatives to evaporative cooling include air-cooling methods, direct-to-chip cooling, immersion cooling, closed-loop systems, and hybrid systems. Each has its advantages and suitability depending on operational needs and environmental conditions.

Air-cooling systems release waste heat directly into the ambient air without using water. These can be used in cooler climates or during certain seasons. Direct-to-chip cooling involves circulating liquid directly to the heat-generating components of servers. In immersion cooling, entire servers or components are submerged in a non-conductive liquid coolant. Closed-loop cooling systems recirculate chilled water or coolant within a closed circuit, minimizing water loss and improving efficiency. Hybrid systems combine multiple cooling methods, using evaporative cooling only when necessary.

A Hydrogeologic Alternative

In addition to these engineering solutions for cooling data centers are the potential hydrogeologic approaches of managed aquifer recharge and geothermal systems. These have received much less attention but have considerable potential.

Hermiston, a small agricultural town in northeastern Oregon, is an example of the use of managed aquifer recharge. In 2025, Amazon Web Services (AWS) reached a 25-year agreement with Hermiston that will allow it to build data centers while providing additional water security to the city.

During low-demand months (October to March), water pumped from the Columbia River will be stored approximately 1500 feet underground in a deep basalt aquifer where it will be available for pumping during high-demand summer months. AWS will have access to some of the water to cool its data centers, while Hermiston will see a net increase of 100 million gallons per year in available drinking water for residents (Hermiston Oregon Public Works 2025).

AWS is covering construction costs associated with the agreement, including the drilling of an aquifer storage and recovery well and installation of necessary infrastructure. The agreement helps conserve Columbia River water during peak summer months, benefits fish populations, and provides irrigation water to local small farmers, allowing them to extend their irrigation season.

Geothermal Cooling

Geothermal systems are a highly scalable solution that can reduce or eliminate water consumption, while potentially reducing overall energy demand through improved HVAC system performance.

A key challenge is matching the system needs, the most efficient heat exchangers, the hydrogeologic setting, and the industry talents to design and construct these systems. These systems require registering them with or applying for permits from the applicable local, state, or federal agency to ensure groundwater is protected.

We’ll now focus on some of the key attributes of three types of geothermal heat exchange systems (see Table 1 for pros and cons of each) that could greatly reduce or eliminate water consumption in a wide range of circumstances.

1. Conventional closed-loop geothermal systems are easily the most recognizable geothermal
technology with a wide base of design and construction resources available in nearly every region of the United States and Canada.

Closed-loop geothermal has defined design methodologies and well-established standards and credentials for designers and installers. They are also relatively low maintenance, being almost entirely constructed of high-density polyethylene and having no subterranean moving parts.

The primary issue with applying this type of system in conjunction with data centers will be managing long-term thermal buildup. Even in northern climates, it is likely that some enhanced controls will be needed to relieve thermal buildup in the subsurface over time.

One approach to managing this buildup would be to combine a dedicated outdoor air system unit with the
geothermal system to reject heat during cooler parts of the year. It is a creative way to ensure stable temperatures by either proactively or reactively controlling thermal buildup in the loop field over time.

2. Pump and injection systems are comprised of supply and injection wells where water is pumped from the supply wells, passes through data center heat exchangers, and is returned into the ground through the injection wells.

When properly designed and installed, they provide the best and most consistent water temperatures, which in turn can yield exceptional and consistent system efficiency to cool the computer servers. Although they pump groundwater, all the water is returned to the aquifer, netting zero water consumption.

Pump and injection systems can generate an immense amount of capacity in areas with ample groundwater resources. Most heat pumps require as little as 2 gallons per minute per ton of unit capacity to facilitate the necessary amount of heat transfer. This contrast allows for large potential capacities in high-capacity wells, faster construction timelines than closed-loop systems, and usually less reserved footprint on site.

A wide range of expertise is crucial. Design engineers will need to contract with experienced hydrogeologists and well contractors to properly identify suitable aquifers in which to design and construct viable wells. Pump and injection systems may still require a large site to ensure that the supply wells don’t short-circuit with the injection wells.

3. Submerged closed-loop heat exchangers installed in wells utilize the convective flow of groundwater as the primary medium of heat exchange. These include accessories such as submersible pumps, a heat exchanger, and piping.

A recent entrant to the geothermal technology arena, submerged closed-loop heat exchangers combine features of the other two types to further reduce the required footprint while still producing high capacities. These factors make this technology ideal for urban environments with suitable aquifer availability.

These systems can generate up to 400 tons of cooling capacity per well in areas where groundwater temperatures are 50℉ and below. They don’t remove groundwater from the ground and use far less horsepower than pump and injection systems.

Although they require specific geologic conditions, they don’t necessarily require areas with large volumes of groundwater. These systems require the use of specialized commercial well drilling companies that can work within limited footprints. They also require advanced control systems.

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In summary, data centers certainly pose some interesting water and energy challenges.

To facilitate meeting these challenges, groundwater professionals have the professional resources necessary to help manage, reduce, or even eliminate water use in data centers no matter where they are located.

Our scientists and engineers can provide research, site evaluations, project planning, and design assistance. Our contractors have the construction assets necessary to install wells and geothermal systems. Our manufacturers and suppliers have or will create the products necessary to support and facilitate the completion of these projects.

Together, groundwater professionals have solutions to ensure our water resources are used responsibly and sustainably.

References

Hermiston Oregon Public Works. 2025. Hermiston water service agreement with AWS (FAQ). www.hermiston.gov/publicworks/page/hermiston-water-service-agreement-aws-faq. Accessed October 29, 2025.

Heslin, K. 2016. Ignore data center water consumption at your peril. Uptime Institute. June 16, 2016.

Shehabi, A. et al. 2024. 2024 United States Data Center Energy Usage Report. Technical Report LBNL-2001637. Lawrence Berkeley National Laboratory, California: 55-58.

Yañez-Barnuevo, M. 2025. Data centers and water consumption. Environmental and Energy Study Institute. June 25, 2025.

William M. Alley, Ph.D., is director of science and technology for the National Ground Water Association. Previously, he served as chief, Office of Groundwater for the U.S. Geological Survey for almost two decades. Alley has published more than 100 scientific publications. He can be reached at walley@ngwa.org.

David Henrich, CWD/PI, CVCLD, is president of Bergerson-Caswell Inc. in Maple Plain, Minnesota. He served as president of the National Ground Water Association in 2018 and received NGWA’s most prestigious award, the Ross L. Oliver Award, in 2022. He can be reached at david.henrich@bergersoncaswell.com.

Charles Job is the manager of regulatory affairs for the National Ground Water Association. Prior to that, he worked at the U.S. Environmental Protection Agency for more than 29 years. He is also a columnist for NGWA’s Groundwater Monitoring & Remediation. Job can be reached at cjob@ngwa.org.