---

Underground irrigation well-suited for high desert

By Faith Bremner
Reno Gazette-Journal
Friday June 23rd, 2000

 

When it came time for Susan and Rob Reeder to install grass at their new southwest Reno house last summer, their landscaper came to them with a novel idea.

Why not irrigate their huge new backyard lawn with an underground watering system that irrigates plants from the roots up instead of from the leaf down, he asked them. The Reeders already had a conventional sprinkler system in the front yard, installed by the contractor who built the house.

The new system, proposed by Reno Lawn and Landscape, sits four inches below ground. There are no sprinkler heads to trip over, no water blowing in the wind and no scheduling conflicts between watering days and yard activities. You can literally mow the lawn and water it at the same time.

But best of all, the below-ground system saves lots of water, according to the manufacturer.

The Reeders decided to go for it. So far, they're pleased.

"The lawn in back greened up so fast this year, much faster than the front lawn," Susan Reeder said. "And it's a very even green.

"For an arid area, it does make sense."

The Reeders don't know how much water they're saving because the house is new and they don't have any old water bills to use for comparison. They also don't know how much more their subsurface irrigation system cost to install than an above-ground system because they didn't price a conventional system.

Kurt Maloney, spokesman for Netafim USA, the company that manufactured the Reeders' subsurface system, said it uses 30 percent to 40 percent less water than an above-ground system. It also costs about the same or a little more to install than a conventional system, he said.

"Even if we are higher-priced initially, there's a cost benefit for saving water," Maloney said. "You're not putting water on the street, you're not causing discoloration of fencing and house siding.

"There are enough other benefits that any cost differences are negligible."

Although subsurface irrigation systems have been around for years, they have been slow to catch on. The perception is that they're expensive and that they do not work well in northern Nevada, where the soils are often rocky and laced with clay. Years ago, a subsurface irrigation system was installed at the Nevada Legislature Building in Carson City and was removed because it didn't work properly.

The drawback to below-ground watering systems is they require much more trenching during installation than the above-ground systems.

But as more and more older homes in Reno and Sparks get water meters and the cost of water goes up, the market for such systems will grow, local lawn experts say.
Although Truckee Meadows residents have enjoyed five wet winters in a row, it's only a matter of time before another drought returns and, along with it, the crunch on outdoor watering.

Subsurface irrigation -- along with drought-tolerant grasses and high-tech evapotranspiration measuring stations that offer watering guidelines based on daily soil conditions -- are tools lawn owners can use to have water-efficient, guilt-free yards, said Bill Carlos, a horticulturist with the University of Nevada Cooperative Extension.

Sierra Pacific Power Co. estimates 65 to 71 percent of all water used by its residential customers in the summer ends up on their lawns.

"People in our area really do need to think about using water more efficiently," Carlos said. "The better we become in irrigating efficiently, the better shape we'll be in when the drought comes.

"We'll already be in that (conservation) mode and we won't have to sacrifice our lawns and landscapes."

Only two subsurface lawn-watering systems are commercially available in the Truckee Meadows, say local landscapers: Netafim USA manufactured in Fresno, Calif., and Evaporative Control Systems made in Reno.

Both systems have been installed in only a handful of lawns in the Reno-Sparks area. Local landscapers want to see if these products work before they start pitching them to their customers.

Evaporative Control Systems (ECS) is installing its product at a practice football field at the University of Nevada, Reno with estimates that it will use 50 percent less water than an old-fashioned sprinkler system. And everybody will be watching.

"I hate to be a pessimist, but somebody has to show me this stuff works first," said Dave Harvey, owner of Reno Green Landscaping.

"If it can be shown to be successful in the variety of conditions that exist here, I can't see why anybody would object to it," he said. "I can see lots of water savings opportunities and that translates into money."

The Netafim USA system consists of half-inch diameter plastic tubing arranged in a grid across the yard. Depending on the soil type, tubing is 16 to 20 inches apart. Inside the tubing, every 12 to 18 inches, is a dripper - a plastic device that releases water at different rates, depending on the soil type.

The system keeps itself from getting clogged with dirt by periodically flushing itself with quick bursts of water.

Maloney won't say how many subsurface systems the company has installed in lawns. However, 20 car dealerships located along the Interstate 80 corridor near Vacaville, Calif., use them to water their lawns. Some have used them for 12 years.

"The system is working for them," Maloney said.
Tom Stille, a landscape architect and gardener, has installed the Netafim USA system in lots of small, hard-to-water places in the Reno-Sparks area for 10 years. As far as he knows, the systems are all working well.

"We generally do not use it in big lawn areas because of the cost," Stille said. "It's like a lot of other things, once you get a specialty contractor in who really knows what he's doing, the cost will come down.

"As water becomes more expensive and more people becoming metered (subsurface irrigation) will become more popular."

The ECS system requires more digging during installation and hardware than the Netafim USA system. But once it's in, the ECS system operates on gravity and capillary action.

The system consists of interconnected plastic half-pipes, which snake around the yard. The pipes are 14 inches across and six inches high and they sit on thick plastic liners. Two inches of fine gravel are poured in and around the pipes to act as a saturated zone. Next comes 13 inches of sand, an optional two-inch layer of topsoil and then sod.

The half-pipes act as a reservoir, filling up on tap water or with rainwater. One-inch square holes near the bottom of the pipes constantly supply water to the gravel- saturated zone. The water travels slowly up the sand column and is always available to the plant roots whenever they need it.

"It's the plants that decide how much water they need and it's not humans dumping water on top, hoping it gets to the roots," said Rita Sipaila, who founded the company with her husband, Jonas Sipaila, last year. "A cactus can grow next to a water-loving plant and they can both thrive because they're both drawing what they need."
***

FIND OUT MORE

For more information about subsurface irrigation systems: www.netafim-usa-landscape.com and www.ecsgreen.com

Installation Cost Comparisons, materials and labor:

Conventional above-ground sprinkler system - $1 to $1.60 per square foot

Netafim USA below-ground irrigation system - 50 cents to $1.25 per square foot

Evaporative Control Systems below-ground irrigation system - $1.60 to $2 per square foot