July is Smart Irrigation Month

(This article first appeared in The Gateway Gardener July 2009 issue.)

Tips for Tuning Your System for More Efficient Water Management

Sometimes water conservation can be a hard sell in this region among great rivers, where water is still plentiful and relatively inexpensive. But even if you don’t have environmental concerns and your water bill isn’t among your greatest financial worries, there is still one very good reason to make sure your irrigation system is operating as efficiently as possible. Says Mike Hartman, president of MPR Turf and Irrigation Supply Company,  “the biggest benefit of irrigating efficiently is in healthier plants and healthier lawns.”

The Irrigation Association, the international organization of irrigation professionals, designates July each year as “Smart Irrigation Month” and uses the opportunity to remind us that there are many ways we can improve the efficiency of older irrigation systems, or install new systems that will water more efficiently than the old hose-and-sprinkler method. Here are some of the tips they provide, with additional suggestions from Mike at MPR.

Check for simple fixes. Misaligned sprinkler heads, obstructed heads, broken parts and clogged nozzles are all problems that occur with standard use over time, and all will result in wasted water running down the street or drowning out your landscape plants. A quick audit of your system can uncover these issues, and just these quick fixes can result in water savings and improved plant health.

Install Pressure Reducing Stems and Check Valves. Excessive water pressure causes water to atomize or mist and evaporate into the air without benefit to your landscape. Pressure reducing stems can reduce or eliminate this wasted water. Check valves will also eliminate wasted water that otherwise drains from the lowest downhill heads after the system has shut off.

Use Rain Sensors and Smart Controllers. Nothing is more disturbing than seeing an automated irrigation system in full operation during a rainstorm. Rain sensors will automatically shut the system off when it rains. Smart Controllers, like the new ET Manager from Rainbird, take it a step further, computing variables such as recent rainfall, temperature, humidity, and solar and wind evaporative effects to determine how fast the grass is losing moisture (evaporative transpiration, thus ET) and how much water to apply to your landscape. Systems can also be programmed to take into account sloping areas and the overall percolation rate of your soil, so irrigation sessions are timed to minimize water runoff.

Consider Drip Irrigation. Whether you install it yourself or have a professional contractor to the job, low-volume drip irrigation can save water and money by putting the water right where you want it—on the plants. Micro-irrigation systems a combination of point source emitters, dripline or emitter tubing, micro sprays, micro sprinklers and bubbler irrigation to slowly and accurately water garden plants,trees and shrubs—not the weeds and bare spaces in between.

“The whole point to a well-designed, well-maintained  system is efficiency,” says Mike. “If your system is 10 years old or older, you could save $200-300/yr. just by increasing the efficiency.  But the most important benefit will be to your plants—they’ll be healthier and happier because they’ll be receiving just the right amount of water—not too much, and not too little.”

Designing a uniform, efficient irrigation system isn’t as easy as some may suggest, so as a last bit of advice, ask if your contractor is certified by the Irrigation Association. For more suggestions on selecting a contractor, visit the Irrigation Association’s website at www.irrigation.org.