Potable water is a precious resource, particularly in drought-susceptible northern California. Water management itself is energy intensive; in California, over 15% of the total electrical energy consumption is devoted to pumping and delivering potable water and treating wastewater. Conserving water protects the availability of fresh water for future generations and is an important step in conserving energy. In addition, limiting human water use helps preserve fresh water habitats for local wildlife and decreases the need to build new dams and other water diversion infrastructure.
Inside the Welcoming Center, we reduced our potable water consumption by over 30% with low flow bathroom and kitchen fixtures. We also treat our wastewater on site, using a low energy treatment method, which was duplicated by the city of San Diego for their municipal water treatment system. Our treatment method involves letting the solid waste separate out in settling tanks and then removing it manually. The wastewater is then filtered through large amounts of sand, treated with a small amount of chlorine, and then released through various pipes (to reduce the impact of any one exit point) into the local environment where it returns to the hydrological cycle. This treatment system is entirely gravity fed, so it requires almost no energy to operate.
Outside the Welcoming Center, we utilized sustainable landscaping to reduce water consumption. We planted native species where feasible to decrease irrigation needs and to attract and feed local wildlife. We do not water the grass around the property, allowing it to go brown in the summer as it is supposed to do naturally. Where it is necessary to irrigate (particularly on the living roof for fire code reasons), we use spring water and recycled on-site rainwater collected in the pond routed by swales. Using recycled rainwater is an ideal solution for irrigation needs because it closely mimics the natural hydrological cycle, as opposed to using large amounts of energy to bring in water from a non-local source.