Technical resources

Some plots of historical rainfall in San Francisco: (uses USGS data, 1960-2007)

Some plots of historical rainfall in Berkeley: (uses USGS data, 1893-2007)

Sample rainwater harvesting calculations in 3 different document types.

Tucson, Arizona is the first municipality in the country to require developers of commercial properties to harvest rainwater for landscaping.All new developments must meet 50 percent of their landscaping water needs by capturing rainwater. The new rule goes into effect June 1, 2010.