By Helene Monkarsh

There’s nothing like a hot, steaming cup of joe to get you up and going on a Monday morning. For easier days, a Peruvian medium roast coffee has just the right amount of kick to get you going, but on tougher days, an Italian double espresso may not be enough. Regardless of what your Monday might entail, you can always rely on the foreign delicacy for your caffeine fix. Very little coffee is produced on American soil. In fact, there are only two regions that are suitable for growing the product: Hawaii and California. Of these two regions, Hawaii is the only one that can sustain the production because coffee is an extremely water-intensive crop. The United States simply does not have the climate nor the water supply necessary to fulfill the domestic demand. What this ultimately leads to, is another country using its water supply to fulfill American needs and an overall increase in America’s water footprint.

A water footprint is a measurement of the amount of water that is directly and indirect used on a daily basis. Arjen Hoekstra, a Water Management professor at the University of Twente, created the water footprint as a way to track the amount of resource that is both consumed and polluted in the production of goods and services. The water that goes into the water footprint, also known as virtual water, is traded among countries in the form of exports. One cup of black coffee has a water footprint of 37 gallons. This number includes everything from the amount of water used to grow the plant, to the amount used to cleaned equipment. A water footprint not only takes into account the amount of water used, but what type of water is used as well. The water footprint can be broken down into three categories:

Blue Water is water that comes directly from the surface or groundwater. This water is typically found in lakes, rivers, and man made reservoirs. This water is either included in a product, evaporated, or transferred to another body of water. The biggest consumers of this type of water are agriculture, domestic use, and industrial producers.

Green Water is water that comes from precipitation. This water is found on the surface level of the ground and in the root zone of soil. Much of green water evaporates, but when it’s not it is taken up by plants for use or transpired. Agriculture, horticulture, and forestry products are the biggest consumers of this type of water.

Grey Water is water that has been used for cleaning and contains things such as soap, oil, food, hair, and grease. This is water that has typically been run through showers, sinks, dishwashers, and washing machines. Grey water is accounted for in a water footprint because it requires freshwater in order to dilute pollutants and meet quality standards.

Additionally, there is one more type of water, Black Water, that isn’t factored in the water calculator, because it isn’t water that is used, but produced. By definition, black water is water that has come in contact with fecal matter. Water doesn’t necessarily have to be contaminated with feces in order to fall into this category, but it does need to be highly polluted. For example, grey water that is left out can become black water in under 24 hours.

Some form of water is used in almost every single process in the world. Whether blue, green, or grey, water is a precious resource that should be used consciously. An understanding of what type of water is used and where it comes from can help society reach a greater level of sustainability.

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