Lake retention time (also called the residence time of lake water, or the water age or flushing time) is a calculated quantity expressing the mean time that water (or some dissolved substance) spends in a particular lake. At its simplest this figure is the result of dividing the lake volume by the flow in or out of the lake. It roughly expresses the amount of time taken for a substance introduced into a lake to flow out of it again. The retention time is especially important where pollutants are concerned.
Read more about Lake Retention Time: Global Retention Time, More Specific Residence Times, List of Residence Times of Lake Water
Famous quotes containing the words lake, retention and/or time:
“Such were the first rude beginnings of a town. They spoke of the practicability of a winter road to the Moosehead Carry, which would not cost much, and would connect them with steam and staging and all the busy world. I almost doubted if the lake would be there,—the self-same lake,—preserve its form and identity, when the shores should be cleared and settled; as if these lakes and streams which explorers report never awaited the advent of the citizen.”
—Henry David Thoreau (1817–1862)
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