At first sight, I recognized the metal roof and large drop-off could easily accommodate rainwater catchment cisterns. The homeowners agreed that using stored rainwater for their supplemental irrigation needs fit their vision to develop the site as sustainably as possible. The harvested rainwater keeps a mostly-native garden flourishing through the Summer heat.
Modular units prevail in this design and include rain tanks, patio pavers, and permeable driveway and entry pavers, all sensitively sited just outside the tree protection zone of giant heritage oaks.