Water is a basic necessity; no living thing can survive long without it. Next to the air we breathe, water is our most important resource for existence. While it may seem that there is an abundance of water, when you consider the composition and availability of the earth’s water a different picture emerges.
- 75% of the earth is made up of water. However –
- 97% of that water is salt water, which means that –
- 3% of the earth’s water is fresh water. But –
- 2% of that fresh water is frozen in icecaps and glaciers. Which leaves –
- 1% of the water on the entire earth available for human consumption.
The human need for water
A few facts about human water usage put our vital need for clean, safe water in context:
- Humans are comprised of 55-60% water.
- We can survive more than a month without food, but only a week without water.
- The average person in the United States uses about 80-100 gallons of water per day.
For good health, it is recommended that the average adult consume 8-12 cups of water per day. A more precise individual estimate of your water needs can be calculated by multiplying your body weight x ½ ounce. (Ex. 150 lb person x 0.5 ounces = 75 ounces of water per day.)
Not all of your daily water consumption needs to come from plain water. Fruits, vegetables and non-caffeinated drinks also contribute to your daily tally. Of course, during exercise or on hot days, you should drink more water to avoid dehydration.