After years of watching other folks' lawn sprinklers watering before, during and after rain storms, and having to remember to enable the "Rain Delay" on my own sprinklers to save water, I finally combined my computer, an X10 controlled outlet, an X10 Firecracker Serial Port controller, a TM751 wireless receiver, a standard 6 zone sprinkler / irrigation controller, the national Weather Service, and a small program I wrote to create an "intelligent" sprinkler system that waters more when it's hot, and skips watering when it rains. Here is how it all fits together:
First, the theory:
And after that, you will never again have your sprinklers running during the rain, or running too little during hot weather. Every day, the computer will check the local weather, and if rain is forecast, the outlet will be switched off. If the forecasted temperatures are warm enough, the outlet will be switched on every day, and watering will occur every day. If the weather is mild, the watering system waters in a set pattern, but not every day.
I have had this system set up for a year, and the landscape has never looked better, while our water bills are half what they used to be.
The web page you are reading is being served from an old AMD K6-III 300MHZ (similar to a Pentium) computer. Since this Web site is always available, this computer is on all the time. Lucky me. If your computer is not on all the time, you can still automate your watering system, but you will have to start the computer up to check with the National Weather service to do it. I would bet that most of you readers run your computer every day, and if not, you run them almost every day. Fine - with the right software and possibly some additional X10 hardware, you can use this solution.
The three ingredients you must concoct:
Put the three together and you are home free.
Would you like more details? Here they are:
# watering system transformer, runs the watering program every day # the program checks the weather and decides whether to run the watering 28 06 * * * /usr/local/bin/water_moreThe Orbit is set to start its watering cycle at 6:30 AM every day.
Does it work? Indeed it does! Here is a snapshot of the log file:
THU High temp: 79 did water FRI High temp: 86 did water SAT High temp: 94 did water SUN High temp: 96 did water MON High temp: 83 did water TUE High temp: 79 did water WED High temp: 79 did water THU High temp: 77 did not water FRI High temp: 81 did water SAT High temp: 86 did waterThe "default" is to only water Monday, Wednesday and Friday. As you can see it was hot when I copied the log and the system was "aware" of it, and it was watering more frequently.
It took a while to get everything assembled and "tuned." If you decide to try the same thing, I hope this page saves you some time. Good luck!
If you are interested in saving water in other ways, check out my home-made Do-It-Yourself Toilet Tank Top Sink Water Saver.