Don’t water when it’s raining.  It’s not the green thing to do!!

How many times have you seen an irrigation system operating during a rain shower?  Did you know that for every occurrence 100% of the applied water is wasted?  Or, have you turned off your irrigation controller when it rains only to finally remember to turn it back on again when your landscape presents you with wilted shrubs and crunchy grass?
Let’s assume your yard is irrigated with 16 rotors.  If each rotor uses 4 gallons per minute and is run for one hour per day, 3840 gallons of water are sprayed each time the system runs and 3840 gallons are wasted each time the system runs while it is raining.  At $3.45 per one thousand gallons (a local rate), that would be $13.25 literally being poured down the drain.
Installation of an inexpensive wireless or analog rain sensor can solve the problem, or, better yet, update your old style controller to a very reasonably priced ‘smart’ controller and weather station combination which can automatically adjust run times to match current temperature and recent rain and watering conditions.