Build your own rain barrel and you’ll get free water for your plants. And you’ll cut down on stormwater runoff, too much of which causes flooding, erosion, and water pollution. Learn more — how to set one up, blend it in, and use it — in this talk by experts at Farm Science Review (pdf; go under “Water Presentations”). Fun fact from the city of Bremerton, Wash., which gets its fair share of the wet stuff: A rainfall of only about a third of an inch, on a typical house, will fill up a typical rain barrel.