Did you know that approximately 70% the earth's surface is covered by water? Of all the water on and in the earth about 97% of it is salt water. This leaves about 3% as fresh water (the kind we drink). About 70% of that is tied up as ice at the polls and in glaciers around the world. The remaining 30% is predominately groundwater, with a little less than 1% being surface water. Of this one percent about 87% is found in lakes, 11% in swamps, and 2% is rivers. These figures from the
USGS help to explain these quantities for those of you who prefer a picture.
With the global population continuing to grow (it is currently
just under 7 Million) the need for more of everything, including drinking water, is becoming a major component of every economy and country. The use of sea water as a drinking source has become a real potential source in many places around the world and some are very close to home.
Check out this article about a desalination plant in Tampa Bay, FL.
Desalination, by definition is the process of removing salt from water (i.e. turning salt water into drinkable water). This process is completed by reverse osmosis. Osmosis is defined as the movement of water through a semi-permeable membrane from an area of low solute concentration to an area of higher solute concentration.
The overall goal being to take saline water (containing at least 1,000 parts per million [ppm] or milligrams per liter [mg/L] of dissolved salts) and converting it into fresh water (containing less than 1,000 ppm of dissolved salts). For comparison, sea water contains approximately 35,000 ppm of dissolved salts.
This technology will only get better as the need for its use grows. Do you know where your drinking water comes from?
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4 comments:
We have a well for our water but I know my neighbors use pesticides on their yards and our land used to be orange groves. We treat our water and have had it tested but water is really so valuable.
Shane you are so right. Fresh water is such a limited resource and many people dedicate their whole lives to protecting it. Depending on how you treat your well water you have nothing to worry about. Florida *where I think you hale from* has some of the most stringent groundwater standards in the US, but you hit on the real problem – you can’t control the impact that your neighbor’s actions have on the groundwater you drink. This situation is why there are so many lawyers around…tort law to the rescue!
Really intersting numbers. I hadn't realized how little fresh water there is and how littel of that is easily usable.
While I read up on these things, I still did not know it was 97% salinated water, wow. Not a surprise when one considers the tremendous volume of the oceans.
Water will only grow as a focal issue moving forward, especially if we start seeing movement of prevailing weather patterns as a result of global warming. Good post!
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