An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »


Supplemental Guidance for WaterSense Certification and Labeling of Weather-Based Irrigation Controllers

EPA requires all products bearing the WaterSense label to be independently certified to conform to the relevant WaterSense product specification. The product certification system describes the application, production process inspection, product testing, and ongoing surveillance requirements to ensure products conform and continue to conform to WaterSense specifications.  

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.