Amid ongoing pressures from California's prolonged drought, Stanford is increasing efforts to conserve both potable and nonpotable water.
A "terrific response from all areas" of the campus community has already generated substantial savings, says Tom Zigterman, director of water resources and civil infrastructure. But additional state-mandated cutbacks and long-term university planning will further reduce water usage, with final totals yet to be determined.
Under new California regulations, Stanford is required to either cut potable water use by 25 percent in comparison with the same months in 2013 or—as the university has chosen—limit irrigation with potable water of ornamental landscapes and lawns to twice weekly. To make the most of its resources, Stanford is also reducing its use of nonpotable water in irrigation by at least 25 percent.
Stanford's nonpotable irrigation system, says Zigterman, is supplied primarily by surface water from creeks, supplemented by groundwater from Stanford's wells. Nonpotable water would be sufficient for all irrigation needs if a delivery system for it existed everywhere on campus; expansion of that system is ongoing.
There have been notable further reductions in irrigation at the Stanford Golf Course and athletic playing fields, and Residential & Dining Enterprises is upgrading its irrigation system, projecting a savings of 33 million gallons a year over the 57 acres of student housing.
All the initiatives work in combination, notes Zigterman, with behavioral changes by individuals and large-scale engineering improvements, such as the water efficiency of the new campus energy plant. Other Stanford divisions have emphasized sustainability issues as well. For example, the expanded Lucile Packard Children's Hospital, scheduled to complete its addition in 2017, will use no potable water for irrigation and save millions of gallons per year through its state-of-the-art appliances and equipment changes.
