As lawns citywide turn brown or are replaced with drought tolerant alternatives, Andy Lauer’s plush green lawn stands out. The front yard has flourished despite being untouched by a hose or a sprinkler for over a decade. The secret behind its healthy appearance? The entire lawn is grown in sand.
This may surprise any passersby because the grass is indistinguishable from a traditional yard. Looking closely, a thin rubber liner separating the grass from the surrounding concrete can be seen. This liner is one of the only visible components of an underground greywater recycling system that supports all of Lauer’s landscaping through a technique known as sand hydroponics. With proponents claiming it uses 75 percent less water than conventional watering practices, this systems represents the future of water conservation and redemption for lawn-lovers in the face of a worsening drought.
The impetus for this innovative system came from Lauer’s wife Melisa who wanted a big backyard for their young children. At the time, their own yard was full of dirt and rocks, so Lauer began to look for help to salvage his yard and avoid moving. He discovered grants available in Santa Monica for those willing to employ stringent water saving techniques. Lauer hired Kevin Poffenbarger, an engineer at EPD Consultants/Construction, who proposed a system that used recycled water. This proposal was initially met with opposition from city and county officials due to safety concerns.
“In the 70s and 80s people were recycling their water in unsafe ways,” said Lauer, who remembered that, “there was quite a bit of opposition based only on the city codes.” However, the officials “weren’t opposed to it as an idea,” recalled Lauer, whose plan finally gained approval at a meeting between Santa Monica City, Los Angeles City, and LA County officials.
Lauer worked over the next two years to install the greywater system, which recycled water from showers, sinks and the laundry machine. “Everything except toilet and kitchen sinks is diverted to a holding tank, and when the garden is ready for water it signals the holding tank to send water down,” explained Lauer, who expanded the system soon after.
“It was working so well that … three years later I installed the same system in the front yard,” Lauer said. “It turned out there was so much good usable greywater being sent right back to the sewer system.” With the installation complete, Lauer’s home became the site of the first legally permitted greywater system in Santa Monica.
This system was developed by Tomas Sapilla and his father Jonas Sapilla, who install sand hydroponics on residential and commercial properties through their company ECS. Sand hydroponic systems reduce significant amounts of water by combining innovative infrastructure with the ingenious natural properties of sand, plants and gravity. Water from rainwater spouts, greywater or other sources is mixed with nutrients and piped into a series of underground holding plastic troughs that are placed upside down. The sides of the troughs are lined with holes to allow the water to exit. Jonas’ innovation was covering the holes with a small plastic awning and using a combination of gravel and sand so that water could access the sand without clogging the holes.
The water seeps out into a layer of gravel, and then meets 13-15 inches of sand (on top of which is a layer of soil). The water is then pulled up through the sand to meet the roots of the plants above through a process called capillary action. “Much like water can travel upwards when absorbed by a paper towel, sand has the ability to draw water upwards and spread laterally,” explained Jonas, “the constant and even movement and distribution of water and nutrients throughout the sand is … termed as sand hydroponics.”
According to Jonas, a 60-80 percent water savings means that every square foot of this system saves 50 gallons a year over conventional watering. Such a system is capable of sustaining any plants, said Jonas in a statement; because it provides everything a plant needs, from high oxygen content in the root zone to excellent drainage. Plants are able to draw as much water as they need, without any water being absorbed to the soil and lost. Sand is also capable of draining very quickly so the system absorbs rainwater efficiently and is capable of capturing up to 0.62 gallons per square foot for every one inch of rainfall.
Lauer’s system can legally use greywater because the recycled water is stored sub-surface, with no possibility for human contact. A 45-millimeter thick rubber liner covers the bottom of the entire system, preventing water loss to the ground below the system.
Unfortunately, these systems have high startup costs. Lauer spent about $40,000 for his backyard system, an amount that covered the primary infrastructure of the system, such as the holding tank, and the necessary changes to his home’s plumbing. Initial expenses for these systems vary from installation to installation, with the largest costs associated with preparing the area to hold sand and construct the initial infrastructure.
“For the homeowner considering their lawn or garden, the average cost below 10,000 square feet is $10-12 per square foot installed,” said Tomas. Projects for fields or parks range from $6.00-$8.00 per square foot. However, the system is much easier to expand.
Lauer’s front yard cost only a third of what the backyard cost because the exterior components of the system were already in place. “The infrastructure was already laid out, and all the pipes had been diverted, “said Lauer. “I just had to tap into the holding tank.”
In addition, low maintenance costs help alleviate initial costs over time. According to Jonas, the underground system is non-pressurized and has no moving parts, meaning less resources needed to maintain it. With few mechanical parts the system needs less downtime for repairs. The system is also permanent; once installed, “it will not decompose or degrade and all parts are totally reusable if relocated to another property,” Jonas said.
With high initial costs, this water recycling system is a long-term investment.¬† “I know I’ve saved almost that in water since I’ve set it up,” said Lauer, whose system reduced not only his overall water usage, but the amount of sewage leaving his property. Lauer said he noticed the water savings immediately, but the city was slower to act.
“One part of the bill is the water that comes in, the intake, and another part of the bill is sewage, what goes back out, and [the City] just assumes what goes in is coming out,” said Lauer.
However, his new system was reusing a significant portion of his water. The city installed a measuring device on the outtake at his home, found out he was indeed using about 60 percent of the water, and backdated his water bill to the lower rate. “My water bill was taken down about 60%,” said Lauer.
Innovative water conservation techniques are salient at a time when business owners and homeowners are being asked, required or incentivized to cut down their water usage.
Many properties have turned to zeroscaping, replacing their lawns with drought tolerant plants, while others simply let their lawns go brown. According to Jonas, however, this practice hurts drought conditions instead of helping.
“Zeroscaping is an ill advised knee jerk reaction to water savings,” said Jonas, who explained that removing lawns increases air temperature, the need for air conditioning and electrical consumption. “The production of electricity is directly related to water use which … often exceeds water use that would have been used in landscaping,” Jonas said.
When Lauer began, his goal was simple. “I wish that I could say that I set out to save water, I’m really not all that heroic,” said Lauer. “I just thought I could save a few bucks by recycling water.” In the current climate of water conservation, however, Lauer feels great about his lawn and champions his practices like a proud parent. “It’s a win in so many ways – it’s beautiful, it works, it’s good for the environment,” he added. “Does it make me feel good? Absolutely. I hear my kids bragging about it.”
For over a decade, Lauer’s family has grown up with their futuristic lawn. But while they may be used to it, the community is still playing catch up. “People come by and say ‘Beautiful garden, but you’re really not supposed to water’,” Lauer laughed.
“And I say, ‘Well, It’s all recycled.’ That’s like telling me and my kids and my family not to shower.”
For more information about Lauer’s business advocating for greywater programs, visit http://www.greywaterconsultants.com