Why we need to conserve water: The Earth’s water
November 9th, 2006 by Mollie
I very briefly explained the water crisis in the introduction. I will use this post to give a more thorough view of the worldwide water situation. As I said before, there is always the same amount of water on earth. The following numbers and percentages can start to get a little confusing, but I have tried to make it as straight forward and easy to read as possible. For those of you who are visual learners (I definitely am) there is a diagram below which should be helpful.
The water that we all need to meet our basic needs comes from fresh water or water that does not contain a large amount of salt. Many of us may remember learning way back in elementary school that seventy-five percent of the Earth’s surface is covered by water. Well, 73.125% of the Earth’s surface is covered by salt water and salt water cannot efficiently be converted into fresh water. This leaves us with fresh water making up only 1.875% of the Earth’s surface.
However, we don’t have access to three quarters of the Earth’s fresh water because it is currently in the form of glaciers or permanent snow cover. You might think, “Hey, let’s just harvest the glaciers and permanent snow cover (psc) and increase our supply of fresh water”. Unfortunately that is a bad idea for many reasons. The main reason being that they are part of our delicate ecosystem and causing any more damage to them than is already being done by global warming would be devastating to the overall health of our planet. What we are left with after salt water and glacial/psc water are taken out of the equation is surface water (rivers, lakes, etc) making up 0.0056% of the Earth’s surface and underground water, which we have some access to through the use of wells, making up 0.46%.
Most people don’t realize that even before any other variables are factored in, the amount of fresh water on Earth is small and limited and the amount we have access to is even smaller. However, the current water crisis is not the result of water scarcity, rather human beings severe mismanagement of it.
Based on the World Water Development Report, “[t]o ensure our basic needs, we all need 20 to 50 litres of water free from harmful contaminants each and every day.” Roughly that is between 5 and 13 gallons per person.
I am going to focus on three situations which are taking place at the moment, all of which are putting a strain on our water supply. The first is that water all over the world is becoming more and more polluted and/or increasingly contaminated with infectious waterborne diseases. Waterborne diseases “are responsible for 80 percent of illnesses and deaths in the developing world, many of them children”. The second problem is that while the amount of potable water available is decreasing, the amount of people that need water is rising because of growing populations around the world. The final factor contributing to our crisis, is that in several communities fresh water is being used faster than it can be replenished.
In the next post I will discuss the problem of water contamination.