Water, water everywhere and not a drop to drink. There may be more truth to that statement than we think. About 70% of the Earth is covered by water. So one would think there is plenty to go around. And, it appears that more water just keeps on coming. It rains-more water. The rivers flow-more water. Wells get drilled-more water. Why, water just keeps coming and coming…there is so much of it and nature seems to keep making more!
The amount of water on Earth has always been the same….more water has not been created. Water moves through the “water cycle” and is not destroyed. So, how much water do we have on earth….and how much is available and usable? Let’s see:
About 97.5% of the water on earth is saltwater stocks. That is to say it’s either in oceans, saline/brackish groundwater or saltwater lakes. That leaves about 2.5% as fresh water. Now, 70% of that freshwater (1.75% of all water) is in glaciers, snow cover or otherwise frozen elsewhere. That leaves approximately 0.75% of all the water on the earth as fresh groundwater.
That is, only 0.75% of all the water on the earth is usable by humans.
Stay tuned, tomorrow I'll talk about The Water Cycle.