Water requires energy.  Pumping it, transporting it, heating it and treating it consume billions of kilowatt-hours of electricity in the U.S. each year.  Producing power creates carbon dioxide, the equivalent of 4 million cars, according to the Natural Resources Defense Council.

Here are some tips/techniques to reduce water usage.  Collect your old bath water or dishwater which is referred to as gray water.  The gray water can be used to water houseplants or for outdoor irrigation.  If you use this water, make sure you use only natural, biodegradable soap to keep from harming your greenery and to keep chemicals from leaching into the water table.

Then there is the water used by the toilet.  Flushing accounts for approximately 30 percent of water used in an average home, according to the Environmental Protection Agency.  If flushing sparingly is too indelicate for you, try a trick used by a clever woman in California.  Place a 2 liter soda bottle filled with water in her toilet tank to displace some water, reducing the amount used in each flush-refill.  You can also buy a bigger float ball or adjust the existing one so it shuts off the refill valve earlier.

Water monitors such as the ShowerTime from Efergy and the Waterpebble track the amount of water you have used in the shower and set off an alarm when you reach a pre-set limit.  Or install faucet aerators and low-flow shower heads to cut back your water use.