How do I calculate my precipitation rate?

Last Update:Feb 18 2022 2:21pm

Summary 


If you are wondering how you can optimize your watering duration for either your Flex Schedule or Fixed Schedule? Or maybe, you are just curious about how you can calculate your precipitation rate? This article can help you with this!


Calculating Precipitation Rate


Precipitation rate (PR) is a calculation of the flow rate (application rate) over the square footage of the zone. Let's break down the equation:

PR = (96.25 * Q) / A

 96.25  = constant that converts gallons per minute (GPM) to inches per hour. It is derived from 60 minutes per hour divided by 7.48 gallons per cubic foot, times 12 inches per foot.
 Q  = gallons per minute (GPM)
= zone square footage (area in ft2)


For further reading and examples of formula application, go here


Note

Feel free to check out one of our Rachio Power User's Drip Emitter Calculator for Precipitation Rate here. It's a Rachio Community favorite!


Do you still need help?


We have a chat support team ready to assist you! You can submit a support request by selecting the chat icon in the bottom right of this page and a member of the support team will contact you live.


Summer Hours (April-September)

7am-5pm (MST), 7 days a week.


Winter Hours (October-March)

8am-5pm (MST), Monday - Saturday. We are closed on Thanksgiving, Christmas, and New Years Day.