Quick Resource: http://wrrc.arizona.edu/sites/wrrc.arizona.edu/files/Quick%20Resouce-%20Active%20WH%20%28final%29.pdf
Other resources:
Basics of active water harvesting http://wrrc.arizona.edu/sites/wrrc.arizona.edu/files/CALS%20Extension_basic%20components%20of%20a%20rainwater%20storage%20system.pdf