We need water to drink, to cleanse ourselves, and to grow food. Landscape irrigation just isn’t a priority when water becomes scarce and local governments roll out water restrictions. In 1992, when Seattle experienced a bad water shortage, one of the lawmaker’s first actions was to cut off all lawn watering. In Colorado, the severe drought of 2000 cost the landscape industry an estimated $200 million in net profits as of January 2003. And that’s just the beginning.

“Every time you see someone watering his lawn when it’s raining, it gives our industry a black eye,” says Kevin Gordon of Hunter Industries, San Marcos, California. While the green industry can’t solve the world’s water problems, neither can we afford to be seen as an entity that wastes water. Water restrictions are hard on everyone, but if we can’t water, we can’t work. This isn’t just about saving the environment; this is about saving ourselves.

Landscape irrigation can take up to 50 percent of a household’s total water use. Up to half of that water is wasted – it evaporates, runs off, etc. But it doesn’t have to be. A variety of tools and technologies exist to address this problem and help save water.

Sprinklers should water with droplets, not mist, which evaporates quickly and forces the system to run longer. Photo courtesy: Walla Walla Sprinkler Co.

Get Smart
“This is a radical change for our industry, and it’s going to be tough, and it’s going to be slow,” says Brodie Bruner, vice president of sales and marketing for Weathermatic, Garland, Texas. “This is an evolution, not a revolution. But that’s no reason to ignore it.”

“The switch to smarter water technology will be as big a change for the green industry as the switch from manual sprinkler systems to automatic sprinkler systems,” says Steven Moore, president of Irrisoft, North Logan, Utah. “And it will also be that permanent.”

“Smart water technology isn’t going to go away,” agrees Tom Penning, president of Irrometer, Riverside, California. “It’s only going to get bigger.” Penning is part of an Environmental Protection Agency committee dedicated to legislating for the use of smart water technology.

Already, many municipalities around the country are offering rebates of up to 50 percent to consumers investing in water-conscious irrigation. In California, there’s talk about mandating “smart” or evapotranspiration (ET) controllers, which adjust watering schedules based on weather, by the year 2010. Other states are sure to follow suit.

But smart water isn’t just a legal issue. Most manufacturers of irrigation equipment are quick to point out that being knowledgeable about smart water application is an excellent way to differentiate yourself from your competition.

“You’re not just selling the same thing everyone else has,” says Rain Bird’s Mike Rivers. “It’s compelling to go to a homeowner and show him the efficiency of a smart water system. If you can show him how much water – and therefore money – he can save in the long run, you don’t necessarily have to be the lowest bidder to win the job.”

Smarter water application makes customers happier, plants healthier, and reduces runoff. Not only is runoff a waste of water that plants can’t use, it can push nutrients that plants need off-site, and can also carry fertilizers and other yard chemicals into storm drains to pollute our water supply.

A smart irrigation system runs the sprinklers only when it senses the landscape is dry. Photo courtesy: K-Rain

Take Control
When programmed and operating properly, there’s no denying that “smart” or ET controllers can produce significant water savings. Irrisoft controller users in Nevada have reported irrigating only 71 days a year according to Moore; HydroPoint controller users in Washington have reported saving $47,000 on water in three months, according to Chris Spain, CEO, Hydropoint Data Systems, Inc., Petaluma, California. And the landscapes have never looked healthier.

The problem is that ET controllers can seem intimidating. They may look complicated or be totally different from anything you’ve worked with before.

“ET controllers aren’t as complicated as the alternative,” says Spain, “I think what’s complicated is having to explain to a customer why he’s being fined by his city for over-watering. I think it’s complicated having a hundred clients, and then the weather gets hot, and you have to drive around to all of their houses, price of gas being what it is,  and adjust all of their controllers individually. Now that’s complicated.”

Spain nails the real beauty of an ET controller – after you’ve initially programmed it, it becomes basically self-sufficient. It will adjust itself based on changing weather conditions and give your clients optimal irrigation every day with no hassle for you.

ET stands for evapotranspiration, which is the amount of water that evaporates out of the soil combined with the amount of water plants transpire out of their leaves. In other words, it’s the amount of moisture lost by a landscape on a given day. If a controller knows how much water a landscape is losing, then it also knows how much water it needs to replace through irrigation.

“ET is usually expressed as a number that represents how many inches of water is being lost. The four biggest factors that change ET are temperature, wind, humidity, and solar radiation,” explains John Addink, president of AquaConserve in Riverside, California. “A sunny day with high temperatures, lots of wind, and low humidity will have a high ET number – a landscape is losing a lot of water – while a cloudy day with low temperatures, little wind, and high humidity will have a low ET number – a landscape is losing very little water.”

ET controllers receive the information they need to calculate ET in a variety of ways. Some collect data from mini “weather stations” installed in a landscape; others download weather information from satellites. Some come pre-programmed with historical ET data and estimate ET based on what it’s been in the past.

There are pros and cons to each method. The controllers that download from satellites require monthly or annual subscription fees, but no other maintenance. “People pay for services they want and need, like cable TV, the Internet, and cell phones,” says Robert Starr of the Riverside, California-based Toro Company. “The ease of satellite-based ET systems will add irrigation controllers to that list.”  Controllers gathering weather data using backyard sensors have no fees, but the sensors may need to be cleaned periodically and occasionally recalibrated.

Controllers that are “smart” but not true ET controllers take temperature readings and adjust irrigation based on temperature only. You sacrifice some accuracy for more simplicity with these controllers. “They’re more user-friendly,” says George Alexanian of Alex-Tronix Controls in Fresno, California. If you’re new to the ET game or uncomfortable with ET technology, these can be a good alternative.

User-friendliness is an issue to consider in any controller purchase. To make them easier to program, some ET controllers come with a worksheet or series of questions about the landscape, asking you to input plant type, soil type, amount of shade, etc. This information helps the controller create the best watering schedule possible. ETwater of Corte Madera, California makes controllers that ask you to fill this information in on the Internet; the controller then downloads weather information and schedules wirelessly.

Rain Master, in Simi Valley, California, offers a controller so user-friendly that it alerts you via e-mail or text message whenever there’s a problem with the system. Calsense, of Carlsbad, California, tried to model its controller menus after an ATM machine so they’re intuitive and easy to use.

“Always look for a system that you find simple to operate, will set a correct irrigation schedule, and will adjust accurately for local weather conditions,” recommends ETwater’s Steve Snow. “You want plants to get the right amount of water, at the right time – no more, and no less.”

Drip emitters deliver small amount of water at the base plants. Photo courtesy: DIG

Sensing Water Savings
The great debate in smart water application is “to ET, or not to ET.” One alternative to an ET controller is installing moisture sensors.

John Fordemwalt, president of Baseline Systems in Boise, Idaho, explains, “ET estimates water use via ET calculations; moisture sensors estimate the volumetric water content of the soil.” Either technology can tell a system when and how much to water; they differ mainly in how they reach these conclusions – ET estimates water loss, moisture sensors estimate water presence.

Early problems with the technology have given moisture sensors a bad rap in the industry. Years ago, some gave inaccurate readings due to varying temperatures, soil chemistry, or the presence of fertilizer. While these problems continue to plague a few current brands, most companies state clearly that their moisture sensors will work under any conditions. “You drop them in the ground and forget about them,” Fordemwalt says.

Penning of Irrometer adds that moisture sensors are also simple to operate and install. They are not as time-consuming to program as an ET controller, so even if you’ve never installed one before, the learning curve will be relatively low. They’re also great for customers who might not want to pay the fees associated with some ET controllers.

Rain sensors are another option. Most won’t adjust a watering schedule, but will at least turn the system off if it’s raining. Many communities already mandate that rain sensors be part of local irrigation systems.

Cool Components
 “Smart water has been a popular buzz word in our industry as of late and often refers to ‘smart controllers,’” says David Levy, president of DIG Corporation, Vista, California. “But controllers are only one component of a smart irrigation system. Elements like ET controllers, low-volume irrigation, and water-wise plants together create a truly smart, water-conserving system.” 

Important elements to consider are efficient sprinklers, spray heads, and rotors. These devices require no special installation education for crews, but can offer significant savings every time they’re used.

Uniformity of precipitation can be given a number rating based on how long you have to run a system to get the driest part of an area to the correct moisture level. Conventional fixed sprays are rated at two, meaning you have to run them twice as long to put enough down for the driest areas. This can waste water and create runoff on the rest of the property.

“Standard ¾” rotors are just over a one on the scale, meaning you might have to run them only about five percent longer,” explains Bob Finnegan from K-Rain of Riviera Beach, Florida. “However, if you have the wrong nozzles on your rotors, you can waste 40 to 60 percent of the water you’re shooting out.”

If you’re using a nozzle that puts out four gallons per minute on a full 360º rotation, don’t use that same nozzle on a rotor going only 180º. The 180º area will be watered twice in the time it takes the 360º area to be watered once. In this example, the 180º area needs a nozzle putting out two gallons per minute; a rotor covering a 90º area would need a nozzle putting out one gallon per minute.

 “The problem is that rotors throw about 30-35 feet. If you’re watering a smaller area, you might want to go down to a mini-rotor, which works efficiently in about a 15-20’ range,” Finnegan continues.

If you want to go even smaller, you might think about the MP Rotator by the Walla Walla Sprinkler Company of Walla Walla, Washington. As you shrink the distance a rotor’s shooting, say from 15’ to 12’, it puts out the same amount of water, but that water is being distributed over a smaller area. This can mean you’re overwatering. The MP Rotator adjusts your flow so that as you shrink the radius of the spray, the amount of water you’re spraying lessens as well, preventing overwatering.

MaxiJet, Dundee, Florida, offers microsprays designed to water even smaller areas. They have hundreds of water-conserving, low-flow, non-atomizing spray heads for different applications, and painstakingly develop each head to get the best angle, spray pattern, distance, etc. for various types of plants.

Pressure regulation in the stem, head, or valve can also produce significant water savings by ensuring a constant outlet pressure – in general, 30psi – no matter how high the input pressure is. A sprinkler operating at 40-70psi tends to atomize water and create mist, reducing the amount of water actually reaching the landscape and forcing the system to run longer. Gordon says that on a typical residential application, this can waste up to 20,000 gallons of water a year. Additionally, a check valve can keep water remaining in the line after a system shuts off from bubbling out of the lowest head, thus wasting water.

Photo courtesy: The Toro Company

Be a Drip
Being called a drip was once an insult, but for an irrigation system, it can be the highest compliment. Drip irrigation is a large part of low-volume irrigation, which is a system that delivers water slowly at a low pressure.

Drip puts down the exact amount of water that a plant needs, right at the plant’s roots, making it an excellent choice for sparsely planted areas. It can also help control weed growth and eliminate run-off.

Drip systems require pressure regulation and filtration. The holes in drip emitters are so small that little particles can cause big problems, so you need to filter the water before it goes through so the lines and heads don’t get clogged.

Some people think that drip systems don’t last as long as other systems. Shovels can tear the tubing, and the filters need to be cleaned occasionally. However, Stan Wagar, director of landscape drip division for Rain Bird, says the advantages far out-weigh the concerns. Additionally, some manufacturers offer kits to make choosing and installing drip irrigation easier.

The popularity of drip systems and other water-conserving products is growing, but not enough. “The cycle of water conservation is typically ‘complacency…complacency… EMERGENCY,’” Keith Shepersky of Irritrol, Riverside, California says. If we move out of our complacency now, we can avoid, or at least lessen, the emergency later. Because without water, the green industry dries up.