The Joy of Xeriscaping
July 19, 2012
The Weekly building doesn't have a whole lot of Seaside soil to work with—just a few narrow strips edging the entrance and downstairs atriums. That's good for the owner's water bills, especially considering the Monterey Peninsula's oy-vey water politics.
But the U.S. Green Building Council also cares how we water these pockets of plant life. The Weekly is reporting a 75-percent reduction in irrigation water use, for three juicy LEED points.
The calculation is a little complicated, BuildingWise Project Coordinator Levi Jimenez explains, since the building doesn't have a sub-meter for irrigation. It involves a model that estimates the water needs based on the square footage of each plant and how much of the site is vegetated. That number is compared to the water used in July by a similar site with grass and mixed plants.
The Weekly scores well in this category because the building doesn't have any turf, which tends to need the most water. What vegetation it does have is "xeriscaped"—a water-wise technique that leverages drought-tolerant plants, mulch and efficient irrigation. Ninety percent of the building's plants are native, Jimenez reports, and all are low to moderate in their water needs.
If we wanted to go for one more point here—representing an 87.5-percent water use reduction—we would probably have to start catching rainwater, Jimenez adds. About 400 gallons could be harvested to further cut back on potable water use.
One final point in this category: landscape waste. LEED rewards the Weekly for having a yard waste bin, which sends weeds and other plant scraps to the regional landfill for composting.
The potted plants aren't included in these calculations, Jimenez adds. It's too bad, because I've gotten into the habit of dumping my stale drinking water into the succulents perched on my desk. Every little drop helps, right?
The Weekly building doesn't have enough square footage of landscaping to qualify for LEED's native habitat point, Jimenez reports. But building owner Bradley Zeve went for it anyway, using an offsite property in Carmel Valley.
"His space is pristine, untouched land which I am attempting to use for credit compliance," Jimenez says. We'll see if the U.S. Green Building Council goes for it.