Wholly H2o - California's Integrated Water Reuse Management Center

Remember, for every inch of rain, about 600 gallons of water can be collected per 1,000 square feet of surface collection area. Use our rainwater harvesting calculator widget (on this page in the right hand column) to determine the amount of water you can recover from your roof and other surfaces during an average year’s rainfall.

Additional information:

• http://www.csunsustainability.org/wp-content/uploads/2010/02/Tivasuradej_Geog306_Rainharvesting_Poster.pdf
• http://ecolocalizer.com/2008/03/23/increasing-water-security-with-rainwater-catchment/