The Water Tower Global Innovation Center, located in Gwinnett County, Georgia, US, is focused on providing solutions for water July Issue 2 utilities in the areas2022 of applied research, technology development, workforce training, and community engagement.
H2O GLOBAL NEWS M A G A Z I N E
Water Quality: The One Water Concept and People Authors: Christopher A. Impellitteri, Kristan VandenHeuvel, Chad Wilbanks, and Melissa Meeker - The Water Tower
The one water concept is internationally recognised, and essentially follows the natural water cycle: from the atmosphere to the earth, to the oceans, and back to the atmosphere.
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rom a water resource management perspective, people collect volumes of water along the natural cycle, use it, and then send it back into the natural cycle in myriad ways.
Let’s start from the beginning. Where did water from earth come from? One theory is that earth’s water came from asteroids and that water associated with asteroids originated from interstellar water that survived the formation of the sun in our solar system. This theory suggests that a significant amount of water on earth is older than the earth itself! Water on earth can ‘leak’ into space through a process called atmospheric escape. This is when water in the atmosphere is broken down into hydrogen and oxygen atoms through a process called photolysis, and then the lighter hydrogen atoms can escape into space. However, this is a very small fraction of the total water in the earth’s atmosphere, so we can think of water as a finite resource on a global scale. The total amount of water on earth has remained relevantly constant for billions of years.
approximately 69% of that water is found in ice and permanent snow. Thirty percent of freshwater is found as groundwater leaving only a very small percentage of freshwater that is more readily accessible on the earth’s surface. The main points of this very brief overview of water on earth are: 1) The earth is not really making any new water nor collecting very much water from interstellar sources 2) Most of the water that we have is not readily usable 3) We must consider usable water as a finite resource. The ways we use and manage water have significant consequences for water quality. Atmospheric water sources, in the form of precipitation, are often thought of as quantity issues (e.g. floods and droughts). Stormwater greatly affects water quality in receiving waters through contaminant runoff. It can also cause dilution or concentration effects on pre-existing contaminants in receiving waters.
But this water is not always in a readily usable form. In addition to water we can see in rivers and oceans, large amounts of water are trapped in rocks and minerals. Some scientists speculate that water locked up in minerals found deep under the earth’s surface may be as much as all the water in the oceans combined. These water molecules can be released back into the atmosphere when volcanoes erupt. For the water we can see (or more easily detect relative to mineral-related water, such as groundwater), 96.5% is salty (oceans, seas, and bays). The remaining 3.5% is freshwater and
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FEATURES
Gwinnett County F. Wayne Hill Water Resources Center, a highly advance facility located adjacent to The Water Tower.
