IrriGRAY Graywater University is a structured guide for learning about efficient re-use of Graywater, Rainwater, Condensate and Potable Water for your landscape.

Key points for each lesson are listed at the top of each page, just like this piece of text. If you already have a good understanding of the key points, you don’t have to continue reading the detailed information underneath!
If you are simply interested in learning the basics of Graywater and the IrriGRAY system, you don’t need to read all the detail.

Detailed information is then presented for the remainder of the lesson. We recommend reading through the detailed information at least once if you are a contractor preparing for our online certification exam.

101: About Graywater >

Certification is a pre-requisite for Resellers and Distributors. Builders may require their Contractors be certified, and Water ReNu will only refer retail clients to Certified Installers and Contractors. This is to ensure the IrriGRAY system, particularly sub surface irrigation dripperline, is installed appropriately for each installation location. 

Example certification exam questions are included at the bottom of each lesson so the reader can check whether they feel they read and understood the content sufficiently to pass the exam (80% of questions must be answered correctly).


IrriGRAY University has been developed by Paul James, VP Research and Product Development. Paul has over 15 years experience with waste water reuse in Australia and the US, and regularly presents at conferences across the US.  Paul is also the author of "The Graywater Guide", has conducted advanced graywater training courses for specialist organisations, and provided advice / guidance related to code development.