Your choice of shampoo could significantly impact our planet’s water resources. The difference between using a liquid shampoo and a solid shampoo or shampoo bar might be more than you realize! So let’s take a deep dive and explore this together.
First, a little primer on the terms we’ll be using. The Water Footprint Network (whose research provides some of the data used in the WFC) defines its components as-
- 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 Footprint of Liquid Shampoos
The water footprint of liquid shampoos depends on numerous factors including its ingredients, the manufacturing process, packaging, and transportation. Let’s make a simplified hypothetical example:
- Suppose it takes about 10 litres of water to produce the agricultural ingredients for one bottle of shampoo (this is a very rough estimate and the actual amount could be much higher or lower depending on the specific ingredients).
- Suppose the manufacturing process uses another 1 litre of water per bottle. Hence the water footprint of 600g of shampoo is 11 litres.
For the HDPE plastic bottle that liquid shampoos generally come in,
- Production of Raw Material: According to some sources, it may take around 1 to 2.5 barrels of water to extract and refine enough petroleum for 1 kg of plastic. Assuming a barrel of water is about 159 litres, and using the higher estimate, this equals 398 litres of water per kg of plastic. For a 50g bottle (weight of 3 x 200g bottles), this would be around 19 litres of water.
- Manufacturing of Plastic Resin: Estimates for the water used in this process are less available, but let’s say it uses an additional 10% of the water used in the raw material production, which would add another 1.9 litres
- Manufacturing of the Bottle: This process is also likely to use water, although specific numbers are hard to find. As a conservative estimate, let’s add another 1 litre of water.
For simplicity, we are not adding the water used in transportation and end-of-life. Therefore, the water footprint of the shampoo bar equivalent of shampoo would be 11 litres + 22 litres = 33 litres.
Finally, the use of the shampoo itself may involve significant amounts of water. Suppose an average person uses 0.02 litres (20 millilitres) of shampoo per shower and takes a 10-minute shower using a showerhead with a flow rate of 9 litres per minute. This means each use of shampoo is associated with 90 litres of water from showering. For 600 millilitres of shampoo, this results in 30 showers per bottle and a total of 2,700 litres of water used in showers.
This makes the total water footprint of shampoo a whopping 2,733 litres.
Water Footprint of Shampoo Bars
Our shampoo bar of 85g, has an estimated 300g of blue water footprint and 300g of green water footprint.
As solid shampoos require 20% less water for rinsing when compared with liquid shampoos, the total WF related to usage is 2,160 litres.
This makes the total water footprint of a shampoo bar 2,161 litres.
the verdict
That’s a savings of 572 litres of water per shampoo bar when compared to liquid shampoo! Incredible, right?
Keep in mind this is a general estimation, and the actual water footprint can vary. We’ve also not factored in the lifecycle usage of plastic bottles and the impact of toxic chemicals that might enter water streams from different shampoos. But this gives us a great starting point for understanding the potential water savings we can achieve simply by switching from liquid shampoo to a shampoo bar.
our impact
Over the past year, together we’ve saved a staggering 3,778,648 Litres of water. Picture this – that’s enough to fill more than one and a half Olympic-sized swimming pools or brew a whopping 1.5 million cups of coffee! It’s an achievement that leaves us astounded, and it’s all thanks to you, our dedicated tribe. You’ve proven that small, thoughtful changes can indeed ripple out to create monumental impacts.
We’re making a difference, one drop at a time, and we’re just getting started! So why not join us on this remarkable journey? By continuing these small yet mighty changes, imagine the amount of water we could save in the coming year. Together, we can turn the tide for our planet’s future!
sources:
- Carbon and water footprint analysis of a soap bar produced in Brazil by Natura Cosmetics – ScienceDirect
- https://www.watercalculator.org/footprint/what-is-a-water-footprint/
- https://www.loreal.com/-/media/project/loreal/brand-sites/corp/master/lcorp/3-commitments/for-the-planet/3-pagers-updates-160523/en/managing-water-sustainably–loral-for-the-future.pdf
