Water Conservation in Data Centres: Innovations for a Sustainable Future

Every byte of data streamed, stored, or shared leaves behind an invisible footprint: water. Behind the smooth flow of information, data centres quietly use large amounts of this limited resource to stay cool and running. As climate change worsens and water shortages increase in many areas, this hidden footprint is becoming hard to overlook.

For the digital infrastructure industry, the discussion can no longer focus only on energy efficiency. Attention is shifting towards water-smart operations. This means looking for ways to save water, using new cooling technologies for data centres, and rethinking what it means to be a genuinely green data centre.

Why Water Conservation is Critical in Data Centres
Large data centres need water to keep servers cool and avoid outages. Local water supplies are under a lot of strain because traditional cooling systems, particularly water-cooled chillers, can use millions of litres annually.

The urgency is obvious:

• Growing water scarcity: Freshwater supplies are running low in many nations, including India. Both industries and communities are at risk from this.

• Operational resilience: Data centres that rely heavily on freshwater may be exposed to local laws and climate-related hazards. 

• Sustainable growth: In order to ensure that data centre expansion is both environmentally and socially sound, responsible water management is essential as digital demand rises.

Increasingly, global sustainability benchmarks and certifications such as Net Zero Water are pushing data centres to not only reduce consumption but also demonstrate measurable water efficiency, reuse, and replenishment outcomes.

Challenges in Water Management for Data Centres 
Despite advancements, data centre water efficiency still faces difficulties:

• Performance and cooling must be balanced: High-performance computing tasks, particularly for AI and GPU clusters, require robust cooling systems, which frequently result in increased water consumption.

• Geographical restrictions: Data centres located in regions with scarce water supplies are more likely to experience operational limitations or require costly substitutes.

• Trade-offs in technology: Making the switch from water-heavy cooling systems to liquid- or air-cooled ones requires a large financial outlay as well as technological advancements.

• Monitoring and reporting: Although it can be resource-intensive, measuring Water Usage Effectiveness (WUE) across complex facilities is essential for accountability.

In addition, maintaining detailed tracking of water inflows, reuse cycles, and discharge quality is critical for compliance with emerging Net Zero Water certification requirements.

A combination of proactive policies, innovative technology, and sound operational procedures is required to address these issues.

Innovations in Water Conservation 
The industry is implementing new cooling technologies for data centres that prioritise scalability, resilience, and efficiency in order to directly address water challenges.

Among the major innovations are:

• Liquid Immersion Cooling: This technique greatly reduces the need for water-based chillers by immersing entire servers in a non-conductive liquid. Data centres that use liquid cooling are more water- and energy-efficient thanks to this method.

• Direct-to-Chip Liquid Cooling: This method uses liquid to remove heat directly from CPUs and GPUs, allowing for precise cooling with minimal water usage.

• Hybrid Cooling Systems: These systems use less water overall and perform better by combining water-cooled and air-cooled chillers. STT GDC India integrates reverse osmosis (RO) plants for cooling tower water reuse and has rainwater harvesting systems installed at select campuses where harvested water supports chiller operations and landscape irrigation.

• Water Reuse and Recycling: Facilities can reuse water several times before needing to replace it thanks to on-site treatment and a higher tolerance for Total Dissolved Solids (TDS). 

• AI-powered Operations: Real-time cooling load adjustments by smart monitoring tools cut down on wasteful water use.

Complementing these innovations are structured water management systems that include rainwater harvesting, treated wastewater reuse, and continuous performance monitoring to maximise efficiency across the entire facility lifecycle.

These developments not only demonstrate dedication to sustainability in data centres, but also how the industry is advancing to satisfy international water management objectives.

STT GDC India’s Water Stewardship in Action
As pioneers in the data centre sector in India, at STT GDC India, we have incorporated water responsibility into our operations and strategy. Our strategy makes use of cutting-edge cooling technologies for data centres, vigilant oversight, and constant innovation. Our important projects include:

• Liquid Cooling Technologies: To increase efficiency while using less water, we deploy In-row Cooling, Rear Door Heat Exchangers (RDHX), Liquid Immersion Cooling, and Direct-to-Chip Liquid Cooling to support some of the biggest AI/GPU clusters in India. 

• Monitoring WUE at Every Location: Water Usage Effectiveness (WUE) is monitored at every facility.

In addition to WUE, STT GDC India has achieved key Net Zero Water certification benchmarks, including a Water Performance Ratio (WPR) of 0.70 and a Water Back to Source (WBS) ratio of 1.69, meeting mandatory certification criteria.

Between 2020 and 2024, STT GDC India achieved a 34.5% reduction in WUE, averaging 0.73, reflecting continuous improvements in water efficiency.

• Water-Smart Site Selection: When selecting new sites, we take water risk assessments into consideration to make sure that facilities are constructed in areas with consistent water supply. 

• Programs for On-Site Efficiency: At Chennai DC2, reliance on water-based cooling was decreased by integrating the piping systems for air- and water-cooled chillers.

Water withdrawals at Pune DC1 were significantly reduced as a result of modifications such as raising Cycles of Concentration, altering conductivity set points, and enhancing high-TDS water reuse.

Advanced Water Management Systems have been deployed across campuses, including the installation of water flow meters on rainwater and irrigation lines, continuous rainwater level monitoring through sensors, and reuse of treated rainwater via Water Treatment Plants (WTPs).

• Non-Potable Water Use: To lessen the burden on nearby freshwater supplies, we give priority to non-potable water sources whenever feasible.

100% of STP-treated water is utilised for landscape irrigation and flushing systems, supported by efficient sprinkler-based irrigation and real-time monitoring through dedicated flow meters.

STT GDC India follows responsible ESG practices across its data centre portfolio, with all sites designed on a Zero Liquid Discharge (ZLD) concept to ensure maximum water recycling and minimal freshwater dependency.

Water treatment and reuse systems such as Sewage Treatment Plants (STP) and Rainwater Harvesting (RWH) are integral to site design, enabling treated water reuse for landscaping, horticulture, toilet flushing, and other non-potable applications. Chiller blowdown water is also filtered and reused to further enhance water efficiency.

To reduce water consumption, water-cooled chillers are progressively complemented by air-cooled chillers, while site efficiency is maintained through design innovations. Condensate and return-line water from PAHUs is collected via dedicated piping systems and reused, supporting a closed-loop, water-efficient operating model.

As a result of these measures, overall water consumption was reduced by 30%, while raw water procurement dropped by 60% year-on-year, leading to total water savings of 1,697 KL and cost savings of approximately INR 2.69 lakh.

Through these initiatives, we at STT GDC India are not only figuring out how to conserve water but are also establishing new benchmarks for the industry's sustainable growth.

The Future of Water-Smart Data Centres
Water efficiency will be the focus of the upcoming generation of green data centres. Future-shaping emerging trends include:

Scalable technologies for liquid cooling

• Increased use of reclaimed and treated wastewater

• AI-driven optimisation of cooling and water systems

• Stricter regulatory frameworks governing industrial water use

Net Zero Water-aligned design and operations will increasingly become a core requirement rather than a differentiator.

Data centres of the future will be inherently water-smart thanks to the integration of digital innovation and sustainable design.

Data centre sustainability must go beyond energy efficiency to include water management as the demand for data storage and AI-driven computing increases globally. The definition of a truly green data centre is evolving due to new cooling technologies such as hybrid systems and liquid immersion cooling.

By integrating measurable sustainability targets, verified under the Global Reporting Initiative (GRI) and Business Responsibility and Sustainability Reporting (BRSR) frameworks, STT GDC India demonstrates that sustainability is not just a practice but a performance metric. With 46.7% WUE improvement, carbon neutrality by 2030, and AI-ready cooling innovations, the company continues to set new standards for responsible data centre operations in India.

Water conservation needs to be a shared priority if the digital economy is to expand sustainably. Data centres of the future will not only spur innovation but also safeguard water, the planet's most precious resource.