The rapid expansion of cloud computing, artificial intelligence, digital services, and high-performance computing has accelerated the development of large-scale data centres worldwide, increasing concerns about their dependence on water-intensive cooling systems. Although cooling is essential for maintaining reliable computing environments and preventing equipment failure, growing facility capacity can substantially increase water withdrawals and consumption, particularly in regions experiencing water scarcity and climate-related resource pressures. This study assesses water consumption and cooling-efficiency challenges associated with large-scale data centre growth and operations. It examines cooling-system design, climatic conditions, computing intensity, facility location, water usage effectiveness, and the relationship between water and energy efficiency. The analysis evaluates conventional cooling towers, air cooling, liquid cooling, immersion technologies, recycled-water utilization, and closed-loop systems as alternative approaches for reducing freshwater dependence. Particular attention is given to balancing thermal performance, electricity consumption, operational reliability, and regional water availability. The study develops a sustainability-oriented perspective for improving cooling efficiency while minimizing water-related environmental impacts throughout expanding data centre infrastructure and operations.