The Natural Water Cycle – How water moves on the earth… and moved mankind

May 19th, 2014

The Natural Water Cycle – How water moves on the earth… and moved mankind

by Jerry Alonzy

cloudsImage via Daniele Nicolucci (Flickr)

According to the United States Geological Service (USGS), approximately 71%% of the earth’s surface is covered with water. Between oceans, lakes and uncountable rivers and streams, there is a remarkably small area without surface water. It’s amazing that more of us don’t have to drive boats to work!

Many areas of the world that do lack obvious surface water seem arid, but not too far beneath the surface the driest areas can have ground water… even vast aquifers with clean, pure water are accessible with modern technologies. Go deeper and there may be more water than exists in all the oceans! (A fascinating story and it’s not science fiction. Stay tuned for my next post!)

Earth’s water supply is virtually unlimited, but that doesn’t jive with the simple fact that there are serious clean water supply issues in some areas of the world.  Similar to the problem we face with natural gas, oil and even food, the problem is not in the supply but in its harvesting, purification, storage and transport. It’s no exaggeration to say that all the water we will even need is right here! All that is needed is the will to reach for the brass ring and do what is needed to get it!

Man’s relationship with water is a quest for freedom…

In the early history of man, we moved in the predictable ways of our animal brethren; and for the same reasons. Survival dictated that we follow food and always keep a source of water nearby. If we didn’t, we would die. But as man escaped the shackles of his genetic heritage, he began his new, unprecedented voyage as a creature less tied to his immediate needs than any other member of the animal kingdom.   He began to learn how to explore for water and how to transport it… absolutely essential for survival when travelling to unknown places.

This freedom, founded in creativity and knowledge gained from passed-on experience, allowed him to take risks and explore his world. He migrated to areas where sources of food and water were scarce, where climates were less hospitable and his creative ability to build shelters, grow food, hunt and collect water allowed him mobility unknown in the animal kingdom. But in the end survival was more dependent on water than anything else.

As omnivores, we can eat most any non-poisonous vegetable or animal. As creative creatures we can make our own environments, keep ourselves warm or cool and escape much of what nature throws at us. But water? We cannot create it and there is no replacement for it. Man can live for a month or more without food, and we can survive in the harshest of climates (properly clothed, of course). But without water our lifespan is reduced to less than a week!

The water cycle… how much we depend on it and use it to our advantage

The natural water cycle is a simple concept, but its effect is universal. All life outside of the ocean depends on it. In short, it is a loop where water evaporates and rises into the atmosphere where the cooler temperatures cause the water vapor to condense into droplets that rain back to Earth, often great distances from the original source. Think of the water cycle as a natural transportation system that spreads water to much of the dry 29%. This clean, fresh water can collect in wetlands and feed streams, lakes or rivers. It may also return to the ocean or soak deep into the earth.

Our planet’s ability to support life, at least as we know it, depends on this cycle, and this cycle depends on the relatively narrow range of temperatures across our planet. Were the earth too hot, liquid water would not exist. Were the earth too cool, all the water would be bound up as ice. Our atmosphere, ironically containing up to 4% water, keeps this range tight… at least compared with our moon, which varies from -380 degrees F. on the dark side to +250 degrees on the sunny side!

Nature’s water purification systems

Mother Nature has two methods of purifying water. The first is in the atmospheric part of the natural water cycle. When water turns to vapor, it does not carry any of the common impurities that we might want to filter from surface water. Organic wastes, minerals of all types and even salt from the oceans are left behind. When the vapor returns to the earth as rain or snow, it is absolutely pure water except for any impurities it might collect from the air. (Perhaps we’ll cover this topic in another article!)

This is the first step in natural water purification. As you may imagine, once the rain hits the earth it immediately becomes contaminated with whatever soluble materials it comes in contact with. Don’t freak out at the word “contamination”. Most of these random contaminants are not deadly, and even those that are toxic are in such small quantities that our bodies can ingest them with no harm whatsoever. This is the water than ends up watering our gardens, in streams, lakes, rivers and into “surface storage” such as natural or man-made lakes and reservoirs.

Secondary purification occurs in two places… swamps or wetlands, and in the Earth itself. Wetlands have many positive functions, including flood protection, shoreline stabilization an as a habitat for wildlife. They also have a role in water purification. Imagine a sudden rainstorm on a solid surface such as a road or parking lot. Any impurities on the parking lot, from automotive lubricants and tire rubber to ice melting products, are picked up by the rain and flushed into the nearest body of water. Now, imagine the same rainstorm in the wetlands. The wetland absorbs much of the water, but still allows slower controlled movement of the rain to the same body of water… but it is first filtered through the porous soil of the wetland, which removes much of the contamination!

Some of the purest water available is underground, filtered by meters or hundreds of meters of various soils and bedrock. Accessible by either shallow or deep wells, ground water is filtered to a level only the best home water filters, such as the Berkey line, can hope to attain. Barring the introduction of persistent surface contaminants, such as some pesticides and herbicides, well water is nature’s ultimate gift to those of us who truly appreciate clean, cool and fresh water!

See these resources for more information on water’s natural cycle:


Author information:
Jerry Alonzy, a.k.a the Natural Handyman, has been an active handyman for over 30 years with experience in most areas of home repair and renovation. As a do-it-yourself author and web developer since 1995, he has been featured in USA Today, the Today Show and on radio shows, magazines, newspapers and websites, including his own at

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