This article discusses the uses and abuses of grey water from sinks and washing machines.
It is an overview of the why's and why-nots of using grey water instead of fresh water.
http://www.survivopedia.com/reusing-grey-water/#There is a link at the bottom of the article to download it as a PDF file.
Our current drought conditions make this a very wise method of extending our limited water supply.
Even if you do not have a garden, you may still reduce water usage by recycling shower and sink water
to the toilet tank. Your septic system will thank you. Your water bill will be reduced too.