IRRIGATION: Dollars in Drip

From a water conservationist’s viewpoint, drip irrigation could be considered the ideal system for watering plants. After all, drip irrigation is 50 percent more efficient than traditional overhead systems, says Mike Stoll, market manager for Netafim USA’s landscape and turf division, Fresno, Calif. Water savings is good news for drought-stricken regions where water has become a valued commodity. But for irrigation contractors, the system must also deliver business for them to consider it a worthwhile endeavor.

Contractors’ success with drip irrigation systems may depend on how well they can sell drip’s additional assets. Water efficiency is the system’s most obvious benefit, but by targeting specific plant material, drip irrigation may also result in less weed growth, lower water bills and faster plant growth.
Besides, in the future contractors may have no choice, as more municipalities will require low-volume irrigation. “You have water management districts telling people that just because you buy water doesn’t mean you have a right to waste it, and because the greatest portion of summer water is used outside, they’re going to start imposing bans to save water,” Stoll says.

So by exploring drip irrigation now, contractors can get a step ahead of their competition, says Janet Reilly, marketing manager for Rain Bird Corp.’s Landscape Drip Division, Glendora, Calif. “It’s a good way for contractors to differentiate themselves and tell clients, ‘I can install drip, save you water and still give you healthier plants,’” Reilly says.

Apparently, more contractors are doing just that. Low-volume irrigation sales have increased 20 to 25 percent annually in the last five years while traditional irrigation systems have been rising in sales by nearly 6 percent each year, according to Stoll. “The significant increase we see on the low-volume side shows that more contractors are moving away from sprays and rotors,” he says.

A HEALTHY DRIP. Property owners typically purchase irrigation systems because they want lush, green lawns and healthy plants. Although drip irrigation is distributed in low volumes, that doesn’t mean plants will be underwatered and dry up. In fact, drip irrigation is said to make plants even healthier than overhead systems because they’re designed to meet each plant’s irrigation needs, whereas traditional systems distribute water over a wider area. Often referred to as point-source irrigation, this type of drip system features emitters the contractor would place at the plant’s root zone. By placing the emitters exactly where the water is needed, the plants should receive more uniform coverage, resulting in quicker plant growth and less wasted water. “It’s targeted, so there’s no overspray or runoff,” Reilly says.

As a result, drip systems can grow plants 50 percent faster than overhead systems, Stoll says. “Increased plant growth comes from putting the water at the root zone where it’s needed,” he explains.

Drip irrigation also contributes to plant health by reducing weed growth because the water isn’t distributed to other areas where weeds may germinate, says Don Hendrickson, president, Hendrickson Bros., Corona, Calif. In addition, the water is being distributed underneath the mulch, whereas an overhead system wets the mulch, which could promote weed growth, Stoll says.

When irrigation contractor Larry Gross markets drip systems to potential clients he often points out how the system lowers landscape maintenance costs by reducing weed growth. “You put 3 inches of mulch down on it, and we experience 80 percent less weeding as a result,” says Gross, general manager of Sunshine Nurseries, Riverside, Calif. “Weed growth is minimal – maybe two or three breaks a year.”

Contractors who are trying to irrigate a wider range may opt for line-source or broadcast drip irrigation. This is where the emitter is premanufactured into the drip line every 12 to 18 inches, Stoll says. “This is good for dense planted areas where your plants are close to each other, so you’re going to irrigate most of the ground,” Reilly says. Because of its wider application range, line-source systems could be considered a replacement for conventional sprinklers, Stoll says. “We simply radiate the water through the soil and use the soil’s capillary action, whereas a sprinkler uses water pressure and gravity to throw the water through the air,” he explains.

In the long run, Reilly says contrac tors’ clients will likely realize more savings from point-source irrigation because it’s less wasteful. “This is because you’re actually designing the system for each plant,” she says.

LABOR DEMANDS. Contractors who are researching the drip-irrigation market may get mixed opinions regarding the system’s required installation time. The type of pipe a contractor uses and the amount of digging involved impact how much labor is necessary. “It depends on the application,” Reilly says. “It can be a lot easier to install if you’re running polyethylene tubing and you have an odd-shaped area because you’re not digging trenches and gluing all the PVC together.”

Polyethylene tubing is more flexible and can be connected above ground so no trenching is required, Reilly adds. Stoll agrees that tubing can result in less labor. “For the most common application, which is putting the tubing into a garden area around a house or building, it’s significantly easier,” he says. “You simply roll the tubing out, staple it down and you’re done.”

However, polyethylene tubing isn’t as rugged as PVC and may be more susceptible to damage from shovels or vandalism, which is why contractor Seth Rutherford says drip irrigation isn’t always the ideal system. Rutherford uses overhead spray systems as much as possible because drip systems require too much maintenance from broken tubing and 25 percent more labor than traditional systems to install, he says. “I like drip for a fixed hedge or fixed hydrangea bed, but it tends to be a service problem,” says Rutherford, president of Waterworks of Nantucket, Nantucket, Mass. “If a gardener is in there cultivating the beds, drip tubing just gets poked and poked because it all has to be buried a few inches down, and he doesn’t see it.”

Gross estimates that drip irrigation requires 15 to 20 percent more labor to install than overhead systems because there are more components involved, such as valves and clocks. But contractor Bill Jenkins says drip irrigation is less labor intensive than traditional sprinklers. “Where you might need a fairly large number of zones with a spray system just to water a given number of plants, drip can do the same with fewer valves, so it’s very cost effective,” says Jenkins, president, Think Green Irrigation, Scottsdale, Ariz. It’s going to be simpler to trench and install, which means it will take less time and labor.”
 
CONSERVATION COSTS. Like labor, personal experience will probably dictate whether drip irrigation is more expensive or less costly to install than traditional irrigation systems. Drip irri gation is 25 percent less expensive than overhead systems, according to Bill Hutcheon, president of drip systems manufacturer Antelco Corp., Longwood, Fla. Hendrickson estimates drip irrigation is 10 to 15 percent less costly than overhead sprinklers.

But installation costs can vary depending on the area being irrigated. “With drip, it’s difficult to say because planting beds are different, and you have different types of plant spacing,” Reilly says. On average, Gross says he spends 25 percent more for drip components than he does for overhead systems. The higher cost means Gross must charge more for drip irrigation than other systems, but he says the client can easily recoup the added expense from water savings. “If they’re spending $5,000 a month on water with an overhead system, they could be spending $200 a month on drip,” he says.

Gross works mainly with developers who prefer that he break down the price per square foot. He first figures what his materials costs are and then adds a 30-percent markup. His fees are about $1 per square foot for a typical drip project compared with 60 to 70 cents per square foot for overhead systems. For smaller projects, less than 15,000 square feet, his average price is $4.50 per square foot, which is comparable to an overhead system. The narrower the area, the more cost effective a drip system will be in comparison to an overhead system because traditional spray systems require more heads spaced closer together, which is more labor intensive to install, Stoll says. 

In the end, profitability on drip irrigation installations is about the same as other systems, Gross says. Jenkins agrees, saying, “All the work we do is bid to be profitable, and drip is certainly efficient to install, but it doesn’t stand out as being any more profitable than any other type of system.”

Many manufacturers and contractors point out that drip irrigation represents more than just profits – it’s sometimes the most sensible solution. “We’re choosing a system not just because it’s cost-effective but because it’s the most appropriate,” Jenkins says. “In the Phoenix area we don’t use overhead irrigation unless there are some extenuating circumstances. In other markets, overhead irrigation is popular because they’re used to installing it that way. But with everyone being concerned about water usage, the benefit of drip irrigation is that you’re using water efficiently.”