Water and Data Centers

This page provides information for those looking to learn more about water program regulations, guidance, and technical tools that are relevant for data centers. By providing access to these resources, EPA is furthering its efforts to provide transparency and potential cost savings for data center developers, local communities, and Tribes across the U.S. 

On This Page: 

• Water Use and Data Centers
• Permitting for Data Centers
• Water Reuse Opportunities for Data Centers
• Opportunities for Data Centers to Collaborate with Local Utilities
• Best Practices for Data Center Water Management
• Data Centers and Water Case Studies

Water Use and Data Centers

The data center sector is among the fastest growing infrastructure sectors in the United States, driven by increased demand for cloud computing, artificial intelligence, and digital services. A primary use of water in data centers is for cooling processors and servers. Evaporative cooling is the most common technique in use, but non-evaporative and immersion cooling are also in use including no-discharge facilities employing closed-loop cooling systems, hybrid air- and water-based cooling, water reuse, and alternative water sources. A variety of data center parameters significantly influence water usage, including: 

• Facility size
• Cooling technology (i.e. evaporative vs non-evaporative coolers)
• Geographic location (i.e. seasonal temperature fluctuations)
• Processor advancement (i.e. heat-tolerant GPUs in development).

Permitting for Data Centers

Data center development and operation incorporate a range of facility designs and wastewater management configurations, including direct discharges to surface waters, indirect discharges to publicly-owned treatment works (POTWs), and no-discharge designs. There are a variety of permits and regulatory requirements that data centers may be subject to at the state and local level. 

• Water-related Permits for Data Centers 

Water Reuse Opportunities for Data Centers

The primary demand for water in data centers is related to cooling, because the servers that are providing data processing to users around the world generate considerable heat. Water utilities that serve data centers may face demand pressure to ensure sufficient water for all customers. Reclaimed water from wastewater utilities can serve as an alternative water source to potable water or freshwater withdrawals. Data centers may also be able to reuse water on site by optimizing their water use. Matching water quality requirements with end uses is important to ensure that facilities do not incur additional expenses by over-treating water that is being used for a specific purpose. Similar to those published in EPA's 2025 Risk-Based Framework for Developing Microbial Targets for Water Reuse, the agency is working to to identify appropriate water quality targets for wastewater treatment facilities that support data center cooling. This work is intended to help inform requirements that state and local governments may include in permits. 

• Water Reuse for Industrial Applications - in the future, this will be built out to more specifically address data centers
• Water Quality Targets and Data Centers

Opportunities for Data Centers to Collaborate with Communities

Engaging early with the community and water utility can help data center operators understand the dynamics of local water resources. In following industrial siting and operational best practices, data centers may consider the five actions below to better integrate their operations into the local water distribution network and community. A future fact sheet will provide more detail for each action.  

1. Engage early with the local water utility to understand their water demand pressures and how the data center water demand may affect the utility's ability to supply water or impact customer water rates. Early engagement can also help ensure that the data center is considering the best technical solutions up front (e.g., cooling approaches that minimize the need for potable water). 
2. Commit to assess water use by conducting audits to identify opportunities to reduce water use and identify metrics such as the ISO Water Use Effectiveness (WUE) standard to set targets and monitor progress in improving water efficiency. Sharing these data publicly can enhance the community engagement process.
3. Optimize operations to reduce water demand, including minimizing peak water demand. Employing less water-intensive cooling systems, such as air cooling or closed-loop liquid cooling, may significantly reduce water usage and demonstrates a commitment to be water conscious.
4. Commit to on-site or supplied water reuse if it will help reduce demand on the local water utility.  (Note: This may be less viable in areas where water utilities are also over-committed on reclaimed water supplies.) If possible, look to help finance infrastructure to treat and reclaim an available alternative water source or commit to pay for connection to a reclaimed water supply.
5. Look to offset an increase in demand (and possible water rates) by providing utilities with funding to help them expand water supplies, conserve water, address distribution system losses, or help off-set increases to residential water bills. If the data center intends to rely on direct withdrawals from ground water or surface water as their source of water, consider developing community agreements to support projects that benefit local water resources (this may already be required in some locations).

Best Practices for Data Center Water Management

Smart water management can help identify water savings across a data center - from sanitary uses to cooling towers to landscape design and irrigation. The resources below can provide a good starting point to identify opportunities for saving water.

• The DOE Federal Energy Management Program (FEMP) has a Cooling Tower Water Efficiency Opportunities for Data Centers website that provides technical resources which can be useful for non-federal audiences interested in strategies for water efficiency in cooling tower-based cooling systems.  
• The Lawrence Berkeley National Laboratory (LBNL) hosts the Center of Expertise for Data Center Energy. The Center includes some resources that focus on Water Efficiency. 
• EPA’s WaterSense at Work offers a compilation of best management practices to help facilities identify opportunities for savings.
• FEMP also has other resources that can help inform water efficiency in buildings.

Data Centers and Water Case Studies

• Water Reuse in Quincy, Washington: Microsoft and the City of Quincy partnered to construct the Quincy Water Reuse Utility, which treats cooling water from a Microsoft data center and recirculates it to the data center for the same purpose, reducing reliance on local potable groundwater.
• Do you have a case study to share?  Contact us at watersense@epa.gov.