Outtake No. 1
Charlie Reagan explains to Arnie Jones on the way to San Diego how much water there is in the world and what the demand is now and may be in the future. These “outtakes” are sections of the manuscript that were removed to allow the story to move along. The reader is encouraged to read them to gain a complete understanding of why we have come to where we are in Water Shock.
“You’re an engineer, so I can talk in figures,” he says and lays out the numbers. People can capture only a fraction of the freshwater runoff and infiltration of 41,000 cubic kilometers per year. Of the 28,000 cubic kilometers per year of flood runoff, the usable portion depends on the capacity of human-made dams and lakes and how often the water in such reservoirs is turned over. The world’s available renewable freshwater lies somewhere between the 9,000 cubic kilometers per year of stable underground flow in inhabited regions and the 14,000 cubic kilometers per year if the stable underground flow in inhabited regions is included, plus the usable capacity in human-made reservoirs[i]. That figure is around 10,000 cubic kilometers . . . “To be conservative,” Charlie adds.
“Hold it a minute,” Arnie says. “I don’t have a clue about the cubic kilometers of water. Help me out.”
“Okay, try this,” Charlie says and explains that there are 325,900 gallons in an acre-foot, which will supply two families of four for a year in the United States. “Okay?”
“So one family uses about a hundred sixty-three thousand gallons per year.”
“Got it, half an acre-foot,” Arnie says, pointing out that per person it’s about 41,000 gallons per year.
“Yes,” Charlie says. “Now, we know the U.S. figures are high compared to the rest of the world, so let’s cut that number to ten thousand gallons per year per person. Still with me?
Charlie runs more numbers by Arnie, saying there are an estimated 12 billion people on the planet. Multiplying 10,000 gallons per year per person times 12 billion is a big number—120 trillion gallons on the demand side. On the supply side, there are 10,000 cubic kilometers of freshwater available, not evenly distributed. So 10,000 cubic kilometers times 850,000 acre-foot per cubic kilometer times 326,000 gallons in an acre-foot is also a big number—2,800 trillion gallons.
“But, Charlie, that’s more than twenty times the demand!” Arnie exclaims.
“Right, but we use about ten to twenty times more water per capita in the U.S. than the water-stressed third-world countries do. I have a great graphic that shows those relative cubic volumes in the form of spheres. The available water volume is shown as a tiny marble, like a small moon. In comparison, the earth is the size of a bowling ball, even though we are a water planet covered ninety-five percent with water.”
Charlie glances at his listener to see if he still has an audience. Arnie looks over, saying, “So?”
“So, in the same reference, there is an appendix that gives estimates of past human population sizes worldwide. In 1900, there were about one-point-six billion people on the earth. By 1990 there were just over five billion, with the expectation that the world’s population would grow by a billion every decade. The last accurate count we have is 2060, and they were right. Twelve billion people now depend on the same nine thousand to fourteen cubic kilometers of freshwater. That’s why I used the twelve billion population number.”
“So, that’s all there is, no matter how many people we put on this planet?”
“How about our state?’
Charlie explains that in California, between the 1950s and into about 2010, the population of Southern California grew from 400,000 to over 20,000,000. Since then the state added a few desalination plants, but no other new water sources. The Delta and the Colorado River are still the main source of supply. Arnie, Charlie says, was fortunate that people with vision built his plant in the late 1970s so the Tahoe-Truckee area became water independent.