My friend Deborah Jones has put together a document (attached here) explaining what are rain gardens, how they work and why they are beneficial. Her website is Cougar Creek Streamkeepers.
I love rain gardens! As a builder down here in Washington state, they have become a regular part of our job, and are considered an option for many of our new homes. Our state requires us to fully contain all roof & driveway runoff on the same property on almost any new home build here. It must go into the ground before escaping the property in any way, so rain gardens have become both a practical and beautiful way to do that. When I drive thru some of the low-cost new home tracts and see that hideous concrete water retention structure right near the entrance usually, it really makes me sad they didn't take just a little more effort & planning to include individual rain gardens instead.
