Water terms can be confusing, especially where water footprints are concerned.
A glossary of water footprint terminology can help people understand the difference between “water footprint” and “virtual water” and how water is connected to food, energy and household goods.
Download a [PDF] version of this glossary.
Water Terms: Water Footprints
Water footprints help individuals, businesses and countries because they reveal water use patterns, from the individual level all the way to the national level. They shine a light on the water used in all the processes involved in manufacturing and producing our goods – what’s known as “virtual water”. They also account for the amount of water contaminated during manufacturing and production.
- Blue Water Footprint
The amount of surface water and groundwater required (evaporated or used directly) to produce an item.
- Green Water Footprint
The amount of rainwater required (evaporated or used directly) to make an item.
- Grey Water Footprint
The amount of freshwater required to dilute the wastewater generated in manufacturing, in order to maintain water quality, as determined by state and local standards.
Water Terms: Water Use
- Direct Water Use
Direct water use is all the water a person sees, feels and uses on premises. That can include water used to brush a person’s teeth, run the dishwasher or water the lawn.
- Virtual Water
It takes water – a lot of it – to produce food, to make energy and to manufacture consumer products. This is what’s known as virtual water, or indirect water use.
How is Water Connected to Food, Energy and Household Goods?
It takes water to grow crops and produce energy; it takes energy to treat and move water; and it takes water to manufacture many household goods like plastic, textiles and metals.
Image: Water towers atop a building in Harlem, New York by Robin Madel.