Cotton and Water: Better Management of An Increasingly Scarce Resource
Photo from Unsplash
The issue of water usage is not a new challenge for the sustainability world, but increasing temperatures and changing weather patterns over the last several decades along with increased water consumption has turned this into an impending crisis. Recently, the U.S. government declared a water shortage on Lake Mead, one of the main feeders of the Colorado River. The declaration will have an immediate impact on more than 40 million people, including farmers across seven U.S. states and parts of northern Mexico. Disputes over water, both in the U.S. as well as internationally, have been on the rise. In 2018, the U.S. Supreme Court adjudicated two separate disputes between states over water supplies. Determining how to protect a dwindling supply of fresh water is one of the most important sustainability challenges we’re facing today.
The United Nations has recognized water as a basic human right, and when it developed its Sustainable Development Goals, protecting water supplies and ensuring universal access to fresh water were key priorities. With fresh water becoming increasingly scarce, yet essential to our survival, ensuring that industries are taking a smart, sustainable approach to water management is more important than ever.
With World Water Monitoring Day coming up on September 18, I thought it was a good opportunity to share some thoughts on the progress cotton has made on water usage. You can read a lot more about cotton and responsible water usage on our Cotton Today website. There’s also a lot of information there on another water-related challenge we’re all facing – the contamination of fresh water supplies with microfibers. I’d encourage you to check it out.
Cotton, like any plant, needs water to grow. However, claims that cotton is a water-intensive fabric are primarily based on misleading water consumption data that has been floating around on the internet for the past 10+ years and are not based in reality. On a global scale, cotton is planted on roughly 3 percent of the global agriculture land and uses roughly the same share (3 percent) of agriculture water. Additionally, the cotton grown on just 3 percent of agricultural land supplies 28 percent of the world’s textile needs. Data like this shows that cotton isn’t the thirsty, inefficient crop the internet would lead you to believe.
The cotton plant is actually drought tolerant and can grow in a variety of climate conditions. Sixty-four percent of all cotton grown in the U.S. relies entirely on rainfall. Of the other 36 percent, only 5 percent is fully irrigated. Amongst all world agriculture, cotton is only responsible for 3 percent of water usage. Even amongst cotton that is fully irrigated, advances in precision irrigation ensure that water is used efficiently. Compared to 20 years ago, we produce much more cotton per acre of land, with virtually no increase (or even a small decrease) in water usage. Technology and better yielding cotton plants have been the key to improving our water use efficiency.
At Cotton Incorporated, one of our main goals is to direct research into continually improving things like irrigation efficiency to help growers use water more intelligently and more responsibly. While the chart above shows a significant increase in water use efficiency over the last 20 years, the story of continuous improvement among U.S. farmers actually goes back at least twice as long. A December 2020 study looked at cotton’s crop water productivity (CWP) over the last 40 years and found that “many factors,” both technological and agricultural, have led to a consistent trend of improved water productivity. More importantly, the study found “the considerable progress over the last 40 years along with the promise of emerging technologies suggest this progress will continue.” While many factors are contributing to this improvement, I wanted to highlight a few here.
Cotton growers are implementing practices like conservation tillage and other regenerative agriculture techniques to improve surface water quality and reduce runoff. Combined with cotton’s progress in reducing the applications of pesticides and fertilizers, cotton growers are working to minimize the impact on water quality. At Cotton Incorporated, we help fund and lead research to evaluate conservation systems and how to produce a more positive impact on surface water quality. These projects provide key data for growers to further improve their management practices.
The industry is also making improvements on the manufacturing end as well. Cotton experts have developed some innovative enzyme technology which dramatically reduce the water needed when treating cotton fiber for dyeing. Cotton Incorporated worked with organizations to develop products that can reduce water usage in the dyeing process by up to 70 percent. A denim mill in Spain has commercialized a waterless “foam-dyeing” technique which can actually reduce water usage by 99 percent.
Altogether, the water consumption of cotton is less than 3 percent of the global average of a person’s total water footprint. Additionally, because cotton is an “and” crop – its byproducts are used for everything from livestock feed to cottonseed oil to paper – all of that water is used efficiently.
Water is essential to our continued existence. And as climate change further pressures our freshwater supplies worldwide, situations like the Colorado River shortage will become increasingly common. This global challenge means it is incumbent on all of us to minimize water use, to increase the efficiency of the water we do use, and to ensure that our actions avoid harming the fresh water sources we all rely on. Over the past few decades, I’m proud of the progress the cotton industry has made towards all of these goals. I am even more excited about the progress yet to be made. In the U.S. the cotton industry has a goal to improve water use efficiency by 18% by 2025, and has also launched the U.S. Cotton Trust Protocol to help the industry measure achievements toward this goal. If you’d like to read more about cotton’s water footprint and some of the innovative research we’re working on, head over to Cotton Today.