Barry Nelson, the director of the Natural Resources Defense Council’s Western Water Project, writes in this essay in the San Diego Union-Tribune, that ” a combination of water-use efficiency, water recycling, improved groundwater management and advanced urban runoff management” constitute a vast “virtual river,” our last untapped water source in California.
California’s future depends on another feat no less astounding than the dam-building projects of yore. Making the most of the virtual river will require a whole new mindset. It will require recognition that every water drop saved â€“ whether by conservation, recycling or groundwater and storm water management â€“ counts as water supply. Those drops add up to more than 7 million acre-feet of water a year. That is more than has ever been exported from the Delta â€“ the largest single source of water in the state. It is larger than the American, the Merced and the San Joaquin rivers combined. Environmentalists and urban water agencies agree that no other future source comes close to the virtual river.