I’m an avid internet comment-reader. I admit it. I know it’s considered unhealthy and often produces feelings of anger (the things people will type behind a keyboard!), but I also find it informative. Unfiltered information about what some people are thinking sheds some light on the reasons why people choose to vote certain ways and make decisions. It also lets me know about the misinformation that can spread like wildfire via the world wide web.
While reading water conservation articles, I often come across the argument that “we have as much water on earth as we had 400 years ago”. I call it the mass balance defence (MBD). It’s a valid statement in itself, but a poor argument against water conservation efforts.
Here are three reasons why the MBD doesn’t hold true for water conservation:
Water on Earth 400 years ago contained less contaminants.
Far fewer people inhabited the earth, fewer factory farms existed, and substantially less man-made chemicals were being produced centuries ago. Without these modern sources of contamination, the water on Earth was much cleaner and safer to drink.
You may recall from grade school that water is the universal solvent, absorbing more compounds in its path than any other liquid. We may have as many water molecules on earth today, but source water is generally not in as good a state to support life as it used to be.
To use water, it must be accessible.
With increased urbanization and desertification, impervious surfaces have also increased (e.g. pavement). When it rains in urban and desert-like areas, water may not replenish the local source that it was extracted from; rather, it moves by stormwater drains or across the surface typically further away from the source, away from where it is usable.
We might have the same mass of water as 400 years ago, but water is heavy and it can be expensive to move and transport to where it is needed most.
It costs money to treat water.
The heart of the issue is that wherever this bounty of water is, it must be potable or near potable for human use -- and that doesn’t come cheap.
Human uses of water -- showering, drinking, cooking, laundering, and industrial uses -- typically require water of potable quality. If you walk out your front door to the nearest water source, it is likely not potable and requires treatment before you can use it. Sure, 400 years ago that water may have been contaminated by deer poop, but 400 years ago human life expectancy of was less than 40 years. Much less than half the 80+ years expected today in North America. We can primarily thank modern drinking water treatment and disinfection practices for that boost in our life expectancy.
And to top it all off, emerging and persistent contaminants (such as microbeads and others found in personal care products) are putting a strain on our current treatment processes and creating a demand for more advanced treatment. Are we prepared to pay for that?
The next time you hear the MBD argument against water conservation efforts, think about why that argument doesn’t hold true. We may have as much water as we did 400 years ago, but the story simply doesn’t end there.