Tah Mah Lah, a LEED-Platinum home on 2.7 acres in Portola Valley, Calif., has a bio-filtered swimming pool, native plants, and an irrigation system that uses treated blackwater and rainwater collected in a 50,000-gallon cistern. But you can’t see most of the features that make this a truly regenerative landscape. It was designed to respond to the natural patterns of wind, water flow, and wildlife pathways, and the cut-and-fill construction process was almost surgically balanced to avoid disturbing the ecosystem and the waste of hauling away leftover soil.

The residence is one of 155 projects invited to participate in the Sustainable Sites Initiative (SITES) pilot program. Launched in 2009, SITES is a joint venture of the American Society of Landscape Architects (ASLA), the Lady Bird Johnson Wildflower Center of the University of Texas at Austin, and the U.S. Botanic Garden. The new certification program mines the possibilities for creating a restorative landscape, whether it’s a custom home, corporate headquarters, or large-scale development.

Aiming to fill gaps in LEED, the SITES premise goes beyond a “do no harm” ethic to helping landscapes actually improve their capacity to clean the air and water, reduce the local heat island effect, provide critical wildlife habitat, and reduce flooding. “It’s meant to guide decisions about how you design, construct, use, and maintain the site so that it doesn’t just protect natural resources but also enables the landscape to be better than it was before,” says Elizabeth Guthrie, ASLA’s manager of professional practice programs.

Tah Mah Lah’s owners, Silicon Valley venture capitalists, were going for “110 percent,” says project landscape architect Thomas Klope of Thomas Klope Associates, Palo Alto, Calif. For example, the irrigation piping is high-density polyethylene rather than PVC, and a sod company developed a special native blend that uses 80 percent less water than conventional sod grass.

But the project also received credits for basic construction measures, such as protecting trees and shrubs with fencing, implementing an erosion control plan, and using excavated foundation soil to backfill the lawn and pool. “We thought about it before we started,” says custom home builder Michael Martuscello, owner of MGM Construction in San Francisco. “Our cut will be this many yards; you’re not overexcavating or underexcavating.”