Source blog 1 for rainwater harvesting

Kloss, Christopher. "Managing Wet Weather With Green Infrastructure." A Municipal Handbook of Rainwater Harvesting Policies Dec 2008: 1-10. Print.

http://water.epa.gov/infrastructure/greeninfrastructure/upload/gi_munichandbook_harvesting.pdf

Third century B.C. first water harvesting systems in middle east: pakistan, afghanistan and iraq. Farming communities from mud-lined rainwater pools. A different name for it is rooftop precipitation collection system. There are lots of different laws about which states and countries can utilize rainwater harvesting in rural homes or even urban buildings.