Earth’s surface is about 70% water. Some people may wonder why water conservation matters. But in fact, 97% of it is in oceans.
That leaves only 3% of all water as fresh water. Most of that is found in glaciers or underground aquifers. That leaves a tiny fraction of all fresh water in all Earth’s lakes and rivers. And about 20% of that is in the Amazon basin.
All life requires water. And all life returns water to the atmosphere. When we exhale, for example, we exhale water vapor along with carbon dioxide. Plants release water vapor along with oxygen.
Along with that water vapor, water evaporates from lakes and rivers. Eventually, it forms clouds. Rain replenishes the planet’s supply of fresh water.
Most places in the world have enough fresh water for human use. Desert areas don’t. The American Southwest, for example, water must be transported from long distances to support the human population. Nearly every place else in the country experiences droughts from time to time. They dry up rivers and lakes and make water supplies dangerously low.
As population increases and technology develops new needs for water, the supply remains constant. In other words, when we use water, we can only use what exists, and what exists has been used over and over. Water conservation is important and becomes more and more important with each passing year.
The importance of water for life
Most of us pay our water bills once a month. Unless we buy bottled water, we don’t pay for water as we use it. So we often don’t think of how much water we use unless our area is experiencing a shortage of water.
Our bodies need water for many functions. It regulates body temperature, aids in digestion, lubricates joints, makes blood and other necessary body fluids, and eliminates toxins and wastes. We lose water through sweat and urine.
Without water, our bodies can’t function properly. For example, when we can’t produce urine, toxins remain in our cells. When we can’t produce sweat, our temperature can get dangerously high.
The average person can only survive about three days without water. Variables include age, activity levels, and overall health. We need more in hot weather to replenish what we lose in sweat, too.
What we eat also affects our need to drink water. Fruits contain a lot of water. I often think of drinking grapes. Salty foods dehydrate us and make us need to drink something. Now, tea, coffee, milk, even sodas or alcoholic beverages provide water. But that water must come from the same basic sources as out tap water.
So far, I have described only human needs. But, of course, wildlife, farm animals, pets, and all plants need water to survive. Not to mention fish and other beings that live in water.
In addition, if we use up groundwater faster than it can replenish itself, it creates an underground void. Gravity pushes earth and whatever is on or in it into the void. The resulting sinkholes can swallow up whole buildings. They are both hazardous to experience and very expensive to deal with.
The possibility and impracticality of desalination
One possible way to increase fresh water is to remove the salt from ocean water. After all, that’s where most of the planet’s water is. The process is called desalination. We know how to do it safely and effectively. It doesn’t depend on uncontrollable factors such as weather. With rising sea levels, we don’t have to worry about running out of ocean.
Desalination plants cost a lot of money, however. They are very expensive to build and costly to operate. There may not be enough returns to justify the investment. It takes about 2 kilowatt hours of energy to make about a quart of fresh water.
One kilowatt hour costs an average of 12¢ in the US. And electricity is not the only operating cost. Much of our electricity still relies on fossil fuels, although desalination plants often use renewable energy. Still, the process entails heavy emission of greenhouse gases.
And the waste from desalination is not only so rich in salt that it can kill wildlife and plant life on contact, it also contains other chemicals. Therefore, the brine has the potential to contaminate our water supply. It is possible to make salt product from the brine. Just prohibitively expensive.
Water conservation importance
Which brings us back to the importance of water conservation. Humans have come to rely on water treatment to make it healthy for drinking, cooking, and bathing. We can find uses for greywater, water we’ve used but not put down the drain. We waste any water that goes directly from the tap down the drain. The water returns to a river or lake. The labor and materials used to treat it are irretrievably gone.
And speaking of water treatment, when we pour various pollutants into our limited fresh water, it increases the cost of water treatment. And current technology can’t remove everything we’ve put into it.
12 biggest pros and cons of desalination / Green Garage, February 3, 2016
How long you can live without water / Jon Johnson, Medical News Today. May 14, 2011
Why is water an important resource? / American Geosciences Institute