What is the main risk for a data centre when the water supply fails?

A critical, and sometimes overlooked, risk of a water supply failure is the impact on backup power systems. Large backup diesel generators often use water-based cooling systems (e.g., radiators with cooling towers) to dissipate heat during operation. In an extended utility power outage, these generators must run continuously. A failure in the make-up water supply can cause the generator's cooling system to fail, leading to the generator overheating and shutting down. This would result in a complete power loss to the data center during a critical period, negating the purpose of the backup power infrastructure.

A. This describes a potential outcome of a system failure, not the direct, primary risk from the water supply failure itself.
B. Direct Expansion (DX) cooling systems are refrigerant-based and typically air-cooled; they do not depend on a continuous water supply to operate.
D. Loss of humidification is a concern, but the resulting change in relative humidity is a slower-developing issue and less immediately catastrophic than a total power loss.

1. Geng, H. (2014). Data Center Handbook. Wiley. Chapter 13, "Electrical Systems," Section 13.4.3, discusses generator cooling methods, which include water-dependent heat exchanger systems essential for continuous operation.

2. ASHRAE. (2021). Datacom Equipment Power Trends and Cooling Applications, 2nd Ed. Chapter 4, "Facility Infrastructure," discusses the interdependencies of support systems, including the reliance of backup generators on facility water for cooling.

3. Uptime Institute. (2017). The Hidden Threat of Water Scarcity. This report discusses the various dependencies of data centers on water, highlighting its critical role in both primary cooling and for backup generator cooling systems.