By Stephanie Tanner, U.S. Environmental Protection Agency (EPA)
When water supplies are tight and municipalities are scrambling to find solutions, it’s often easy to target local landscapes with watering restrictions. Nationwide, residential outdoor water use exceeds 7 billion gallons of water each day, most of which is used for landscape irrigation. Experts estimate that as much as half of this water goes to waste due to evaporation, wind, and improperly scheduled irrigation systems. But with smart irrigation technologies on the rise, there may be a better way to water using Mother Nature as a guide.
Look for the label
EPA created the WaterSense label in 2006 to help consumers find products that save water and perform well. To date, more than 4,000 models of plumbing products have earned the label. Working with more than 2,000 utility, manufacturer, retailer, distributor, and irrigation professional partners, WaterSense has helped consumers save 125 billion gallons
of water and $2 billion in utility bills over the past five years.
With the release of its final WaterSense Specification for Weather-Based Irrigation Controllers, EPA opens the program to the first outdoor watering product eligible to earn the label. Weather-based controllers use real-time, local climatological data to schedule irrigation. Once properly installed, these controllers can do the thinking for homeowners and facility managers in terms of when and how much to water outdoors.
The WaterSense specification covers stand-alone controllers, add-on devices, or plug-in devices in residential and commercial applications. WaterSense-labeled irrigation controllers must be tested and certified to meet performance requirements based on the Smart Water Application Technologies (SWAT) protocol. SWAT includes performance measures of irrigation adequacy and irrigation excess, which measure how well the system meets plant water needs without overwatering. The specification also requires supplemental capabilities such as the ability to change irrigation schedules to accommodate local watering restrictions and the ability to connect to a rainfall device.
EPA has held various working groups, conducted independent research, and worked with numerous experts to determine the appropriate performance characteristics and testing protocols to ensure WaterSense-labeled controllers provide sufficient irrigation to promote plant health and meet the needs of landscape managers and utilities trying to reduce water waste.
Mother Nature beats the clock
An estimated 13.5 million irrigation systems are currently installed in residential lawns across the United States, and an additional 308,000 new systems are installed each year as a part of new home construction. The industry estimates indicate that less than 10% of the units already installed use weather-based controllers to schedule irrigation. Currently, the most common method used to schedule irrigation is a manually programmed clock timer that irrigates a specified amount on a preset schedule programmed by the user.
Clock timer controllers can be a significant source of wasted water, because irrigation schedules are often set to water during the height of the growing season, and might not be adjusted to reflect seasonal changes or changes in plant watering needs. Although plant water requirements decrease in the fall, many homeowners forget to reset their irrigation schedules, and landscapes will be watered in October as if it were July. Overwatering plants also results in shallow roots, weed growth, disease and fungus.
As an alternative to clock timer controllers, weather-based irrigation controllers can make irrigation schedule adjustments automatically by tailoring the amount, frequency, and timing of irrigation events based on current weather data and landscape conditions, applying water only when the landscape needs it, and promoting a healthier, more attractive landscape.
Partnering with professionals
As the demand for “smart” irrigation technology increases, so does the demand for cutting-edge irrigation professionals. Proper installation, programming, and maintenance are key to ensuring that weather-based irrigation controllers save water on landscape irrigation and reduce runoff.
Professionals who have successfully completed a WaterSense-labeled certification program that focuses on water-efficient irrigation automatically qualify to become a WaterSense partner. EPA recommends homeowners and facility managers look for a WaterSense irrigation partner to design, install, audit, or maintain irrigation systems to ensure controller performance. WaterSense-labeled new homes that include an irrigation system require design or installation and audits to be conducted by an irrigation partner. Each year, WaterSense singles out one such partner and recognizes his or her efforts to promote water efficiency.
“My designs are only as good as the equipment in my legend,” explained Christopher Curry, the 2011 WaterSense Irrigation Partner of the Year. “The work done by the manufacturers in smart controllers really helps the overall goal to save water.”
To learn more about the WaterSense Specification for Weather-Based Irrigation Controllers, find WaterSense-labeled products, or learn more about WaterSense irrigation partners, go here.
Photo: EPA
