Smart Irrigation TechniquesJuly 2008
By Amanda Richter
Besides Independence Day, there's another reason for contractors to celebrate July: Smart Irrigation Month. As July is one of the peak months for landscape water usage, it's a good time to look closely at smart irrigation practices, water-saving irrigation products and water efficiency in general.
With the EPA's WaterSense program at the helm, there are a growing number of resources available to help us use our water wisely. Although landscape irrigation is often painted as one of the chief water wasters, contractors are in a unique position to influence other water consumers to tread lightly.
The following examples of smart irrigation offer proof of this spirit. By using forward thinking and efficiency-based approaches, the people involved have impacted water use for the better. And as these stories prove, there is a competitive edge to be gained by displaying water smarts.
Smart water technology benefits contractors and clients
Is there really opportunity in smart water services? Terra Management Services, a Houston, Texas-based landscape management contractor, thinks so. At many commercial facilities, up o 60% of the water used is for landscape applications, making it a prime target for conservation. Terra focuses on intelligent water management and the benefits of efficient irrigation for its clients. The company projects that it can cut water use at its clients' facilities by 50% or more. This approach has given Terra business growth and increased customer loyalty.
In 2003, Terra took over work at the office complex for WesternGeco, a division of oil-services giant Schlumberger, and faced the challenge of trimming the facility's more than nine million gallon annual water usage. The 26-acre facility consists of several buildings, a meticulously managed lawn of hybrid Bermuda and extensive landscape plantings. Terra didn't want to lose important maintenance services or harm the seven-figure landscape investment by cutting back on water use. Still, they had to figure out how to execute better water management.
Their solution was to call in WaterLogic Inc., also located in Houston, which specializes in retrofitting and managing smart irrigation control systems. Through the partnership with WaterLogic, Terra was able to launch water management services without recruiting its own team of technicians.
Initially, Frank Bertolino, facilities manager at WesternGeco, wondered if a significant reduction in water would have a negative impact on the landscape. However, the smart water technology that Terra presented to Bertolino doesn't just cut back on water use; it works to eliminate wasted water, which actually creates a healthier landscape.
The WaterLogic smart water system is comprised of its own server and Rain Bird ET Managers, which automatically adjust irrigation schedules based on real-time weather data. The ET Manager do not replace irrigation controllers; rather, they work with controllers to calculate evapotranspiration (ET). A network of weather stations broadcast solar energy, wind speed, temperature and humidity data to the ET Manager, while rainfall is measured onsite to pinpoint each site's unique moisture conditions.
The advantage of using real-time weather data, says WaterLogic President Charlie Racusin, is that the information is never more than 59 minutes old. Terra could program its controllers to irrigate as often as they wanted or needed, but with the ET Manager, irrigation will take place only when necessary and in the proper amount to maintain optimum soil moisture. This can eliminate the watering-during-a-rain-event conundrum that has plagued irrigation contractors for years.
Working closely with Terra's horticultural experts, WaterLogic's water conservation consultants installed four ET Managers throughout the WesternGeco site and began monitoring water use. In the first year, water use was reduced by 68% (6.4 million gallons) without any harm to the landscape greenery. Paul Marks, public relations director for Terra, adds that a reduction in water wasn't the only benefit to upgrading to the new system. "Monthly monitoring of water usage led to the discovery of a major mainline leak that went undetected for years because it was leaking into a storm drain," he says.
Bertolino adds, "We have seen a twofold gain-the property actually looks better, and we achieve the look by using less water. So, we are not only reducing the impact on a delicate resource, we are saving money."
Marks notes that commitment to smart water management enables Terra to exceed the scope of the base relationship it has with its clients. He says, "Clients feel that we are looking out for their best interests. Today, there is not a strong demand for water efficiency, but as the 'green' movement grows, clients will become more aware of what smart water technology can do. And as states and municipalities demand reduced water usage, clients will be more motivated to consider smart water technology."
Irrigation retrofit reduces overwatering
Less glamorous but vital sprinkler heads also play a part in solutions to water efficiency. When it comes to sprinkler heads, Ted Sirkin, operations manager for Valvette Systems in Woodland Hills, California, says that low-tech trumps high-tech design. His line of sprinkler parts makes maintenance simple, provides higher uniformity and eliminates misting over-spray by regulating flow and pressure.
Last March, while looking to achieve greater irrigation efficiency, Frank Gonzales, parks and landscape superintendent for the city of Agoura Hills, California, called on Valvette Systems to test a median strip along one of its main streets. The median strip, 10' wide and one city block long, was divided into four landscaped areas, two turf and two shrubbery.
Four remote control valves (RCVs) with approximately 27 heads per valve irrigated the median. The heads were triangularly spaced and carried 8' and 10' nozzles, the recommended sized for a 10' median strip. However, over-spray and excessive misting from the sprinklers would saturate the streets bordering the median. Over time, this could have caused damage to the infrastructure.
To begin the test, the old sprinklers in the RCV #3 area were replaced with Little Tuffy 6" pop-up sprinklers. The sprinklers contain LittleValve pop-up stems, which use a simple set screw below the nozzle and filter to shut off water at the sprinkler head, allowing the nozzle to be removed for servicing or maintenance. Agoura Hills' new sprinkler heads were equipped with 15' nozzles.
After the retrofit, misting and overspray were eliminated, minimizing the potential for roadway deterioration. Within days, the controller registered a 50.7% reduction in water in the test area. This reduction did not have a noticeable effect on the turf's viability.
Over the next few weeks, the run-times of the two RCVs that irrigated the turf areas were adjusted to test for higher uniformity and determine whether a reduction in runtime would stress the turf or affect its viability. The runtime of RCV #3 was cut 25% from 12 minutes to nine minutes for six weeks. An average of 364 gallons of water, or about 58.9%, was saved per day without any noticeable negative effects on the turf when compared to the section irrigated by RCV #4, which irrigated for 12 minutes. However, when a May heat wave set record temperatures, the test section started to display signs of stress.
So the runtime of RCV #3 was increased to 16 minutes, while the runtime of RCV #4 stayed at 12 minutes. Both RCVs irrigated for three straight days to revive the turf in the test area and restart the comparison. After the three-day period, data indicated that RCV #3 still experienced water savings of about 132 gallons per day (21.7%) despite the longer runtime.
Following this test, both RCVs were reprogrammed to water four days per week at 12-minute runtimes. During the last period, about 297 gallons daily (44.5%) were saved in the RCV #3 area. On June 4, Gonzales again lowered the runtime on RCV#3 down to 10 minutes, increasing the water savings to 53%.
The Agoura Hills project, one of several similar tests across the country, shows the importance of irrigation innovation in all forms. Sirkin likes to compare irrigation systems to the military's chain of command. "If controllers are the generals, then valves are the sergeants, and sprinkler heads are the privates," he explains. "A unit is only as good as its privates. If the privates aren't doing their jobs, then the war is lost." Similarly, if a sprinkler head isn't functioning correctly and causing overspray or misting, water is lost. And when it comes to a resource as valuable as our water, every component is important, regardless of rank.
The future of smart irrigation
As we look into the future of smart irrigation, certain issues will become more important for contractors. Keith Kuehn, manager of corporate marketing for Rain Bird Corporation in Tucson, Arizona, says, "Contractors, as the frontline of the industry, will be entrusted with telling the story of effective, efficient and responsible water usage."
For Kuehn, "effective" means using the right amount of water at the right time. "Efficient" water usage minimizes or eliminates waste. And responsibility entails helping people understand the proper landscape design, irrigation system and plant selection for a given climate.
In their more public roles, contractors should be prepared to adapt to legislation that is developing in response to the scarcity.
Mike Baron, director of water management for Toro Irrigation in Riverside, California, warns that contractors who don't learn new water-saving landscaping and irrigation skills have the potential to lose business. "Contractors need to make themselves knowledgeable about designing and installing irrigation systems that reduce water usage without compromising the beauty and functional use of a landscape," he says.
Mounting concern about the cost of water will require greater focus on efficient irrigation products. Baron says the cost of water to users will increase much faster that the rate of inflation in the next 10 years. With higher costs and limited water supplies, water budgets will become prevalent.
Some commercial clients put the responsibility for meeting their monthly water budgets on the shoulders of contractors. As contractors may have to pay for additional usage. It's important to have your finger on the pulse of new products and techniques.
Baron also notes the increased involvement in water efficiency from a manufacturing and distribution standpoint. "Irrigation products are getting more precise and efficient. This includes irrigation components such as nozzles, which produce a slower, more even application of water to reduce runoff. Some have features that shut off water is a spray head when the nozzle is removed. We're seeing more smart controllers tied to ET information, and increased interest in moisture sensors as well."
Flow sensors are also becoming more common and are starting to move into the residential market. Using these kinds of products offers significant opportunity for contractors. More and more consumers are embracing a green ethic that contractors can tap into with success.
Kuehn thinks reclaimed water use and drip irrigation will likely see increased growth, too. "There is increased interest in drip irrigation," he says. "Both contractors and property owners are asking smarter and smarter questions about drip irrigation. A contractor needs to ask him or herself whether he or she is equipped to have a well-informed conversation about drip irrigation with a customer." If not, taking classes to educate themselves will help contractors be as informed as possible.
With higher prices and the growth of water-efficient products, Kuehn places importance on WaterSense and third-party certification programs that rely on performance metrics to authorize the effectiveness of water-saving products. He points to Australia's Smart Approved WaterMark program, which relies on independent testing labs that have no commercial stake to test water-saving products before a review board grants certification.
Kuehn believes that a similar standardized testing procedure for U.S. products would help contractors discuss these products in a way that relates them to customers' needs and raises the credibility of the industry.
The move towards greater water efficiency is underway. And with change comes new opportunities for contractors. Now is the perfect time to re-examine our attitudes about irrigation and ask what it really means to be a part of the green industry.
Article as appeared in Irrigation & Green Industry Magazine, July 2008, page 13 - 20.