Most comprehensive Rainwater Harvesting tutorial ever
So I never wrote this, wish I had. It is likely one of the most comprehensive semi technical Rainwater Harvesting documents I have ever read. If you want to know all the basics and much of the intricacies of collecting your own rainwater than this document is for you.
Its long but covers everything from design, filtration, and best practices. Every person dealing in rainwater systems should give it a good read, I know Ill get all our staff to.