Embedded water, also known as virtual water, represents the total volume of freshwater utilized throughout the entire production supply chain of a commodity, product, or service. This includes all water used from raw material growth to manufacturing, processing, and transportation. It highlights the often-unseen water consumption associated with everyday goods and services. Understanding embedded water helps quantify the environmental impact of consumption patterns, encouraging informed decision-making regarding water resource management.
What is Embedded Water in Products?
Embedded water is calculated by considering all water inputs across a product’s lifecycle, including three categories: green water, blue water, and grey water. Green water refers to rainwater stored in the soil, consumed by plants through evaporation or transpiration. Blue water is sourced from surface or groundwater, used for irrigation, industrial processes, or domestic purposes. Grey water quantifies the volume of freshwater needed to dilute pollutants generated during production.
The amount of embedded water varies significantly based on production methods, geographic location, and efficiency. For example, producing one kilogram of beef requires approximately 15,400 liters of water, considering the water needed for feed crops, animal hydration, and processing. In contrast, one kilogram of wheat requires about 1,827 liters of water.
Common items demonstrate this variability:
A single cotton t-shirt can have an embedded water footprint of around 2,700 liters, primarily due to cotton cultivation.
One kilogram of rice requires about 2,500 liters of water.
A kilogram of cheese uses approximately 5,280 liters.
A single apple contains about 70 liters of embedded water.
A kilogram of bananas requires around 500 liters.
Global Impact of Embedded Water
The concept of embedded water has broad implications for global water resources, particularly in relation to water scarcity. Countries effectively “import” water through goods from water-stressed regions, which can alleviate domestic water demands but potentially exacerbate water issues in exporting nations. This creates complex interdependencies in global water resource management.
Approximately 20% of the water used in global food production is traded virtually. Agriculture dominates this virtual water trade, with products like livestock, wheat, maize, soybeans, coffee, and cocoa accounting for over 70% of the total volume. This trade has grown significantly, increasing 2.9 times from 1986 to 2022.
The environmental consequences extend beyond mere consumption, affecting local ecosystems, water quality, and biodiversity in production areas. For instance, approximately 16% of unsustainable water use and 11% of global groundwater depletion are linked to virtual water trade. Understanding embedded water is thus important for global sustainability and managing finite resources, especially as climate change intensifies droughts and depletes aquifers.
Reducing Your Embedded Water Footprint
Individuals can significantly reduce their personal embedded water footprint through conscious consumer choices and lifestyle adjustments. Focusing on food choices is particularly impactful, as a large portion of an individual’s water footprint is hidden in their diet. For example, opting for less water-intensive foods, such as plant-based alternatives to meat and dairy, can substantially lower one’s footprint.
Reducing food waste is another effective strategy, as discarded food represents wasted water resources used in its production. Planning meals, proper food storage, and consuming leftovers can help minimize this waste. When purchasing goods, choosing durable products and supporting brands that prioritize water conservation and sustainable practices in their supply chains also contributes to a smaller footprint.
Direct water conservation in the home, though a smaller part of the overall footprint, also makes a difference. Fixing leaks promptly, installing water-efficient fixtures like low-flow toilets and showerheads, and taking shorter showers are practical steps. These individual actions, when collectively adopted, contribute to broader efforts in sustainable water management and resource preservation.