Today’s post is by Cavin Costello, the designer of the Castaway House:
The Castaway house is nearing completion and the central focus of the design, the landscape, is currently being installed. Jeremy Stapleton of Synergy Design Lab worked in collaboration with us from the very beginning to create a design that focused on desert indoor/outdoor living. The result was a beautiful and functional landscape design, which Jeremy describes as an “Edible, Medicinal, Sensory & Wildlife Garden.” This garden expands the interior of the house into nature and its neighborhood; all while being water efficient.
There are numerous active and passive systems involved in the design of the landscape to maximize the little water we receive here and it starts with harvesting. The site is designed and graded to drain into 6” recessed planting beds that are zoned by varying water demands to harvest site rainwater and keep it from wasting into the city sewers. All the rainwater from the roof is collected into 2, 600 gallon tanks. These tanks are then hooked up to an irrigation system that is controlled by an Evapotranspiration based irrigation controller with a rain sensor that corrects for site conditions. This low-volume system uses the stored rainwater, when available, to irrigate the plants through drip emitters.
The question you might be wondering now is how much rain can you harvest off your roof with the minimal 7” a year we get here. The Castaway House is 1970 square feet but its roof area, because of overhangs and its carport, totals 2907 square feet of catchment area. Over one year, the rainwater harvesting system will limit the use of city water in the landscape at the Castaway House by an estimated 13,513 gallons. All we can do once the system is hooked up is a little dance and wait for some rain.
Photo credit: All photos by the author.Tags: Cavin Costello, jeremy stapleton, phoenix, residential rainwater harvesting, synergy design lab, The Castaway House, The Ranch Mine