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The Top 10 Green Issues of 2008


8
What is gray water and can it solve the global water crisis?
It might not be potable, but gray water is perfect for your plants.
It might not be potable, but gray water is perfect for your plants.
Courtesy Robert Cianflone/Getty Images

­Y­ou may have noticed a sudden uptick in dirty cars and withered lawns due to the sweeping bans on outdoor waterin­g. But you've probably also seen signs assuring the public that operational sprinklers aren't breaking any laws -- they're just shooting out something called "gray water."

Gray water is the wastewater that drains from your sinks, shower and washing machine. Unlike black water (the wastewater that leaves your toilet and is best kept in the sewers), gray water can be treated and reused in your home without much fuss. While small concentrations of detergent, food particles, skin and fecal matter make gray water unsafe for drinking, your lawn and ornamental plants won't mind a bit.

­You can collect gray water with professionally installed systems that hook up to your washer, or tote buckets yourself. Gray water alone can't stop our immersion in what the United Nations calls a "water crisis," but combined with conservation, it could definitely help. Learn more about collecting wastewater in What is gray water and can it solve the global water crisis?

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