cotton and water use

Jul 25, 2015 :: by Pam Allen

Since our first couple blog posts on our journey developing Willet, (post 1, post 2) our new yarn made from California-grown acala and pima Cleaner Cotton™, we've received a few questions about water usage in cotton growing. As many of our readers will know, California is experiencing an extended and severe drought, and every drop of water used to grow any crop in California is a drop that must be pulled from depleted water reserves.

We asked Lynda Grose, spokesperson for the Sustainable Cotton Project and their initiative, Cleaner Cotton™, to write a guest post for us about the issue. Lynda has more than two decades working on sustainability in the fashion sector and related industries. She explained the water implications of growing cotton, both in California and around the world. Here is her response.

Thanks for your interest in cotton and water use.

Everyone involved in fashion and sustainability struggles to provide scientifically based information in language that is accessible to the public, without diluting the facts.  The questions from your readers provide us an opportunity to dig deeper. So thank you to your readers for taking the time to participate in this dialogue and ask insightful questions.

Cotton is arguably the most scrutinized fiber on the planet, partly because its cultivation is wide open and accessible to study.  There are several blanket statements that have circulated about water and cotton that have become memes. 'Cotton is a thirsty crop' is one of these, and the total gallons of water used in producing a t-shirt are another.  

Scientists, farmers and fashion professionals working deeply on sustainability wince at these statements, because the fashion industry is global and the path of producing a t-shirt is enormously complex, so actual water figures depend on a wide range of factors. These include: where in the world the cotton was grown, what farming system was used, how and where the t-shirt was dyed, how it was finished and even the washing habits of the wearer.  

To provide a single figure that represents water use in a t-shirt, experts 'normalize' data.  That is to say, they produce an average from overall data gathered from global cultivation sources and different garment production scenarios.  There are accepted methods for doing this, so the statements aren't wrong per se, but it is erroneous to draw conclusions from applying an average to a specific region of cotton cultivation. 

For example, water use on cotton in Uzbekistan is notoriously bad and has depleted the Araal Sea, once the fourth largest inland sea in the world.  In contrast, cotton is rain fed in West Africa and highly efficient irrigation systems are used on cotton in Israel. Yet, people tend to apply blanket information on water simplistically to all cotton growing regions, without fully understanding the nuances about farming in different areas.

Regarding the cultivation of cotton in California specifically, here are a few points:

  • Cotton in California is irrigated and this helps achieve the consistent high quality long and extra long staple fiber qualities. 
  • Farming in California is highly technical and fine-tuned and farmers have access to scientists and the best available technology, unlike many other cotton growing regions in less developed parts of the world.
  • Studies have shown that cotton is a moderate water user in California, taking far less acre-feet of water per acre than almonds, pistachios, alfalfa, corn and many other row crops. In this state, almonds require an average of 3.5 acre-feet of water per acre, while cotton requires an average of 2.5 acre-feet of water per acre.
  • Cotton is also a relatively small crop for California (almonds represented 1,020,000 acres in the state (2014), and cotton 161,000 acres (2015) (figures from National Ag Statistics). So the water demand for crops like almonds are much greater in California than for cotton.

Cotton also thrives in water deficit conditions at certain times in its lifecycle and this information is provided to farmers to influence their growing practices. When cotton bolls form, for example, farmers deliberately cut back on water so the plant produces more bolls and fewer leaves. This also reduces water losses through leaf transpiration.

In addition, since cotton is an annual crop, farmers can choose not to plant it if they have reduced water allocations. In fact, California cotton acreage has gone down in recent years as farmers have chosen to direct their water to other “permanent crops” such as almonds. This is not because cotton is a large water user, but because permanent tree crops represent a large capital investment for the farmer and they must protect that investment.

Finally, water in California is relatively expensive and cotton is a low value crop, so it doesn't make economic sense to use a lot of water on cotton.  In fact farmers often weigh the cost of another water application with the projected increase in yield and hold back if the cost is likely not to be recouped.

Rather than demonizing a particular crop, I prefer our focus to be on the root problems, the economic, industrial and social systems that do not always work well within the constraints of natural resources. If there is one good thing about the drought in California, it is that it has raised public awareness tremendously about living within nature's boundaries and this is influencing policy on agriculture and consumer behavior at the state level.

See: 'Your Call Radio for some robust discussions on water in California from multiple perspectives: http://kalw.org/programs/your-call.

Related posts in: Cleaner cotton |
Back to article grid