Freshwater is a finite resource under increasing pressure from a growing global population and changing climate patterns. Understanding how humanity divides and utilizes this limited supply of water is paramount to addressing future scarcity challenges. While many people associate water use with daily household activities, the reality of global water allocation is distributed vastly differently than most imagine.
Categorizing Global Water Use
Hydrologists and policymakers track water resources using two key concepts: water withdrawal and water consumption. Water withdrawal refers to the total volume of water removed or diverted from a source, such as a river, lake, or aquifer. Much of this withdrawn water is temporarily removed and eventually returned to the local environment, often at a different temperature or quality.
Water consumption, conversely, is the portion of the withdrawn water that is permanently removed from the immediate water cycle and is no longer available for downstream use. This includes water lost through evaporation, transpiration by plants, or incorporation into a product. Evaluating both withdrawal and consumption rates provides a clearer picture of regional water stress and the long-term impact on local water supplies.
Agriculture The Largest Water Consumer
Agriculture is the activity that uses the most water globally, responsible for approximately 70% of all freshwater withdrawals worldwide. The vast majority of this demand comes from irrigation systems required to grow crops for food, feed, and fiber.
This high rate is due to the nature of farming, where water is consumed through evapotranspiration (evaporation from soil or transpiration through plants). Inefficient practices, such as traditional flood irrigation, contribute significantly to consumption by allowing large volumes of water to evaporate before crops can utilize it. Crops requiring long growing seasons or cultivated in arid regions, like rice and cotton, are particularly water-intensive.
Producing a single kilogram of rice can require between 1,000 and 4,000 liters of water, depending on the farming method. The water footprint of livestock is also embedded within this total, as over 90% of the water used for animal production is dedicated to growing feed crops like corn and soy. Irrigating these large-scale feed crops in dry areas places a substantial strain on blue water sources (surface and groundwater accessible for human use).
Water Use in the Industrial and Energy Sector
The industrial and energy sector is the second-largest user of global freshwater, accounting for roughly 20% of the worldwide total. Demand is primarily driven by cooling and manufacturing. Thermal power plants (coal, natural gas, and nuclear energy) are the single largest industrial withdrawers of water.
These facilities require massive volumes of water to condense steam and cool down mechanical systems. This specific usage is characterized by a high withdrawal rate but a relatively low consumption rate, as much of the water is returned to the source after use. The portion that is consumed is mainly water lost to the atmosphere through evaporation from cooling towers.
Beyond power generation, water is consumed in manufacturing products like textiles, paper, and chemicals, where it becomes embedded within the final goods. Mining operations also require substantial water for processing and dust suppression. Although the industrial sector’s percentage is substantial, its overall consumption footprint is much smaller than agriculture’s because a large fraction of the water drawn is released back into the system.
Municipal and Household Water Requirements
The municipal and household sector is the smallest segment of global water use, representing approximately 10% of total freshwater withdrawals. This includes water delivered for domestic consumption, public services like firefighting, and sanitation. Although the water used in homes is the most visible to the average person, it constitutes a minor portion of the overall global demand.
Within a typical home, the largest uses are concentrated in the bathroom and laundry room. Toilet flushing often accounts for the single largest portion of indoor water use, followed by showering and running faucets. While these activities are essential for public health and hygiene, the total volume required is small compared to the needs of global food production.