I once heard a story of a person buying a new motor home, setting the cruise control and getting up and leaving the drivers seat while underway. What in the world does this have to do with a sprinkler system? Well, most people do something just as absurd with their new sprinkler systems. Most system owners set the controller (cruise control) and walk away, wasting away our precious H2O resource.
It’s true an automated sprinkler system is touted as saving water, but it will only do so if it is operated properly! Changing the water times of the controller is essential for efficient application of water; we’ve all seen the worst cases of this as an automatic system is watering away in the rain, or watering ½ mile of street side gutter over applying and wasting water. The majority of “hose draggers” put at least some thought into whether, and how much, the lawn and landscape needs water. An owner of an automated system should be no different, assessing the controller program weekly or more to match water times with the weather and infiltration rate of the soil.
I see more and more a reference to “an inch per week” in a feeble attempt to quantify the water needs of the typical landscape in the typical setting by the typical person for the typical weather, you catch my drift. In reality if you are applying 1” of water in March you are significantly over watering unless of course you live in a VERY arid region, leaving some level of adjustment and interpretation to the owner. The industry is attempting to rectify the problem by developing “smart” technology, some of which is simple, economical, and works great such as rain sensors that hold a system off while it’s raining and for a period of time afterward, moving towards the very sophisticated such as controllers which receive daily ET (evapotranspiration) rates and adjust water times automatically based on soil types, sun exposure etc.
The common sense approach seems to make the most sense to me. Take advantage of technology as you see fit, at a minimum install a rain sensor and learn to utilize the seasonal/global adjustment feature available on most current controllers. If true water conservation is a goal, seek a professional that is current with the available technologies and be prepared to spend a little more, but rest assured, the resource and your pocket book will be all the better in the long run.
By Brent Stevenson, Certified Landscape Irrigation Auditor