Water Barrels seem like an easy way to conserve water to me.  Recently Regional Water Providers released a discussion that exposed some of the cons of rain barrels.

They make some good points like this one. ” So, if you have a 100 square foot patch of lawn you will need about 62 gallons a week to water the recommended 1 inch.    Assuming you will water this grass from May-September, you will need to collect at least 1300 gallons of water. That translates to about 24 rain barrels!”

It still seems to me that anytime you can use the water from your roof to water even a few plants on days that the rain is far away its a conservation win and saves money too.   Read and decide for yourself.