“We welcome the first clear day after a rainy spell. Rainless days continue for a time and we are pleased to have a long spell of such fine weather. It keeps on and we are a little worried. A few days more and we are really in trouble. The first rainless day in a spell of fine weather contributes as much to the drought as the last, but no one knows how serious it will be until the last dry day is gone and the rains have come again.”
(from I.R. Tannehill, Drought: Its Causes and Effects, Princeton University Press, Princeton, New Jersey, 1947)
Unlike other natural disasters, drought does not have a clearly defined beginning and end. As a result, our reaction to drought traditionally has not been timely.
©2006 National Drought Mitigation Center
Rain Barrels are a great introduction to the world of Rainwater Harvesting. However, they are only good for small gardens or patios. If you are just suplimenting the occasional dry week great, but if you want be ready for the next drought or long dry period get a tank. Look at your local rainfall history. Start planning 3-4 weeks of reserve and leave room for another tank down the line.
Also take a look at my rain barrel page at the top to find out good tips on building your own or what to look for when you buy one. Remember, have at least one 1 1/2″ overflow directed away from the house and ending in an area that will not erode. Secondly, make sure your barrel is opaque so not to allow sunlight to cause an algae bloom.