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The Ultimate Gray Water Quiz
by Staff
The world's population is exploding and water supplies just can't keep up with the demand. How can you help conserve the Earth's limited water resources? Check out our quiz and learn about gray water and how it can be used to make a difference.

How many gallons of water does the typical American household use per day?

  • 200 gallons (757 liters)
  • 400 gallons (1,514 liters)
  • 600 gallons (2,271 liters)

Many state governments in the United States have issued bans on:

  • bathing
  • outdoor watering
  • using a dishwasher

According to Water -- Use It Wisely, running your _____ only when full can cut down considerably on water use.

  • dishwasher
  • washing machine
  • both of the above

Gray water is _____ that drains out of your washing machine, sinks or shower.

  • wastewater
  • rain water
  • clean water

In the United States, water consumption increased by _____ percent between 1960 and 1990.

  • 42
  • 52
  • 62

The wastewater that leaves your toilet is called:

  • black water
  • gray water
  • whitewater

The best use for gray water is:

  • irrigation
  • bathing
  • dishwashing

Which cleaning agents in laundry detergents are actually good for your soil?

  • phosphorus
  • nitrogen
  • both of the above

Gray water systems should be entirely underground and irrigate plants:

  • on a slant
  • at the roots
  • by spraying

Which types of plants is it safe to irrigate with gray water?

  • lawns
  • root vegetables
  • tomato plants

An outdoor air-conditioning unit produces 10 to 15 gallons of _____ on a hot summer day.

  • bubbles
  • waste
  • condensation

What's the simplest way to collect water from a window-mounted air conditioning unit?

  • Place a bucket underneath it.
  • Buy an expensive water collecting kit.
  • Attach a hose to it.

What is the biggest drawback of a professionally installed gray water collection system compared to the do-it-yourself methods?

  • It is more complicated.
  • It is messier .
  • It is more expensive.

What amount of gray water is safe to use in your garden?

  • a half gallon (1.89 liters) of gray water per square foot of soil
  • a gallon (3.79 liters) of gray water per square foot of soil
  • two gallons (7.57 liters) of gray water per square foot of soil

If Americans used only gray water to water their plants, they would save 6.6 billion _____ of water every day.

  • quarts
  • liters
  • gallons