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> only for the water saving aspect
Actually, being sure that the sprinkler system is truly off is a significant issue. Apparently, sprinkler solenoid valves stick open and the results are big water bills.
I'm working on a related issue with the deep well that supplies the geothermal heat pump. If the discharge solenoid doesn't close properly, the pump just runs needlessly --and that pump is an expensive pita to replace. I've just put a flow switch in the pipe that I can monitor and have ordered a relay which will tell me if the pump is running.