Seven Reasons for Installing an Automatic Rain Shut Off Device:
It's all about maintaining beautiful, healthy vegetation. Rain water is purer and healthier for plants than piped water. Notice that no matter how carefully a watering program is managed, turf, ornamental plants, and vegetable gardens are always at their best just after a rain event. Piped water has chemicals and picks up metals from the pipe. Well or surface water has organisms that, while not really harmful, detract from water purity. When a irrigation / sprinkler system cycles during or right after rain, it dilutes the benefits of pure rain water and can cause beneficial rain water to run off or seep deep into the ground below the root zone.
Over-watering caused by simultaneous rain and irrigation cycling is bad for plant life. It leeches beneficial nutrients from the soil and can deprive the roots of oxygen.
An automatic rain shut off device saves money--lots of it. One inch of water applied to one fourth of an acre is 6780 gallons. At rates as high as $4.08 per thousand gallons, that's $27.66 per cycle. The cost of a wired rain shut off device from SprinklerWarehouse.com is as low as $16.93--considerably less than the cost of a single watering cycle. If the rain sensor prevents just one watering cycle per season, it literally saves its cost every year.
Rebates! Many water providers offer rebates that cover the cost of the device before it even prevents a single rain event.
A irrigation system operating during rain reflects badly on the property owner. Passers by don't know that a sudden rainstorm has come out of nowhere while the residents are away for a few hours or the business is closed for the evening. They just see carelessness.
An automatic rain shut off device helps to conserve and protect natural water resources by reducing the amount of water that is wasted and the amount of pollutants such as fertilizers and pesticides that run off the turf and flow into waterways and groundwater.
More and more water providers are requiring rain shut off switches on all automatic lawn irrigation systems within their jurisdictions. If it's not required by the local jurisdiction yet, installing one early means it will probably pay for itself before the law even takes effect.