Water_ The Epic Struggle For Wealth, Power, And Civilization Part 12

Yet until the early 1930s the river was completely untamed. Newly elected president Franklin Roosevelt was personally determined to change that. When Congress balked at the extraordinary cost of erecting a high dam at the remote Grand Coulee that would provide far more hydropower and irrigation water than anyone imagined could be profitably used by the 3 million inhabitants of the region, Roosevelt started the project on his own from other relief funds. In the end 36 huge dams would be built on the Columbia and its tributaries between 1933 and 1973-nearly a dam per year. The multipurpose Bonneville in 1938 and Grand Coulee in 1941 were world-cla.s.s supergiants of their era. Thousands were put to work building them. To help win the public relations battle over the utility of the dam, Roosevelt's staff hired folk balladeer Woody Guthrie as a research a.s.sistant. In his folksy midwestern tw.a.n.g, Guthrie communicated the inspiring grandeur of the dam project, in songs like "Roll on, Columbia," as the mightiest object ever built by man.

When finished, the Grand Coulee Dam was indeed the mightiest thing ever built: four-fifths of a mile wide, 550 feet tall, three times the ma.s.s of the Hoover Dam, generating half as much hydroelectricity as the entire country at the time, and capable of irrigating over a million acres. The giant concrete plug in the great canyon backed up the artificial Franklin D. Roosevelt Lake some 150 miles to the Canadian border. Downriver, the Bonneville was already generating electricity and taming the wild five-mile rapids with big locks that enabled the pa.s.sage upriver of large barges transporting farm produce and bauxite to the aluminum smelting industry that developed around the region's rapidly expanding availability of electrical power. By the late 1980s, the Columbia River was providing 40 percent of America's total hydroelectricity.

Like Hoover and the other multipurpose giants of the era, Coulee's hydroelectric sales heavily subsidized the building of the dam and a.s.sociated irrigation project costs. Yet in the late 1930s, carping critics of Roosevelt were still wondering loudly who would buy so much excess electricity. History, however, repeatedly demonstrated that the development of a useful resource inevitably found unimagined and unforeseen productive applications. Yet no one could have antic.i.p.ated just how swiftly the great need for the northwest's surplus electricity would arrive. Only five days before the completion of the dam, j.a.pan attacked the American fleet at Pearl Harbor. The United States entered World War II. The war's extraordinary mobilization and economic stimulus caused airplane factories and aluminum smelters to spring up throughout the region. By 1942, 92 percent of Grand Coulee's and Bonneville's electricity output was powering war production. Most of it went to producing thousands of warplanes bound for the aircraft carriers that turned the war in the Pacific in America's favor. An aeros.p.a.ce industry vital to the war effort also arose in Southern California on the electricity available from the Hoover Dam. j.a.pan and Germany had nothing to match it.

It was no exaggeration to say that America's superior industrial productive capacity in general-and its vastly superior and timely availability of hydroelectric power in particular-played a decisive role in the nation's rapid rebound from Pearl Harbor and its ultimate victory in the war. Indeed, rarely in history had exploitation of a water resource so dramatically and immediately affected the military outcome and the rise of a great power. During the war, Coulee's electricity also powered the top-secret Hanford military installation on the Columbia in Was.h.i.+ngton State to help produce the plutonium-239 that made the United States the preeminent nuclear superpower of the postwar era.

Less than three months after his dedication of the Hoover Dam, Roosevelt signed off on another immense water-moving and irrigation project for the West's third great river basin that ran through California's 450-mile-long, 50-mile-wide Central Valley. Its scale dwarfed the volume of water that Hoover Dam was delivering to the Imperial Valley in Southern California. Set in the basin of the San Joaquin and Sacramento rivers between the Sierra Nevada and Coastal mountain ranges, the Central Valley Project transferred water from California's wetter north to its arid south. In the process it transformed a region as dry as North Africa into America's produce capital and the richest concentration of irrigated farmland in the world. A small boom of private irrigation in the Valley had occurred around World War I when large farmers began to use motorized, centrifugal pumps powered by oil or electricity to tap deeply into the region's store of groundwater. Through the 1920s, some 23,500 well pipes pumped up prodigious amounts to be able to luxuriously irrigate the San Joaquin Valley in the southern Central Valley, and helped California surpa.s.s Iowa as the nation's leading agricultural state. But by the early 1930s the uncontrolled groundwater pumping had caused the water levels in its large aquifer to plunge so drastically that thousands of acres had to be retired for want of irrigation water. As the aquifer emptied and drought conditions prevailed on the surface, the big farmers of the Central Valley turned reluctantly to the government for relief.

Inspired by the ambitious water transfers of the Hoover Dam project, they proposed a water transfer plan that would s.h.i.+ft resources from watersheds in the north, which were filled by the rainfall and spring snowmelt, to the south through a series of large ca.n.a.ls covering hundreds of miles and supplied by two new giant dams. At the heart of the scheme were the Shasta Dam on the Sacramento River and the Friant Dam on the San Joaquin. In essence, the Central Valley Project was a bailout for existing, mainly large farm businesses. What it was not was a reclamation plan intended to create many new small farms as foreseen by the original 1902 legislation. But in the midst of the Depression, Roosevelt approved it anyway. In 1934 the Dust Bowl had hit the midwestern plains, destroying farmland and starting the internal ma.s.s migration to California. "The Central Valley Project was without question the most magnificent gift any group of American farmers had ever received; they couldn't have dreamed of building it themselves, and the cheap power and interest exemption const.i.tuted a subsidy that would be worth billions over the years," wrote Mark Reisner in his cla.s.sic work on western water history, Cadillac Desert Cadillac Desert. "It rescued thousands of farms that were already there, including many that were far larger than the law allowed."

The federal waterworks were followed in the early 1960s by another gigantic, entirely state-built California Water Project that moved water even more ambitiously through a network of dams, reservoirs, and hundreds of miles of aqueducts-featuring a section that pumped water, with an extravagant expenditure of energy, over over an entire mountain range in five stages, including a final, Herculean two-fifths of a mile lift. By the time the water started flowing over the mountains in 1971, California was by far the most intensively water-engineered place on the planet. Every big river flowing from the Sierra Nevada was dammed. an entire mountain range in five stages, including a final, Herculean two-fifths of a mile lift. By the time the water started flowing over the mountains in 1971, California was by far the most intensively water-engineered place on the planet. Every big river flowing from the Sierra Nevada was dammed.

New Deal western waterworks also had their counterparts in the nation's eastern half. Most celebrated was the Tennessee Valley Authority. Launched in 1933, the TVA attempted nothing less than the comprehensive management of the entire Tennessee River basin, three quarters the area of England, with the declared purpose of raising the economic and social well-being of its downtrodden inhabitants. The TVA's sweeping powers were governed by an independent public body whose precedent was the special authority granted to the Panama Ca.n.a.l Commission. Throughout the 1920s progressives in Congress had stymied presidential plans to privatize the government's big dam at Muscle Shoals, its nitrate factory for munitions, and other a.s.sets on the Tennessee River through sale or lease to big businessmen such as Henry Ford. Through the TVA, those a.s.sets were converted by the New Deal into the centerpiece of an ambitious, state-managed effort to produce electricity, flood control, irrigation water, improved navigation, and even nitrate and phosphate fertilizers for the region's farmers. No other river in the world had so concentrated an amount of its volume dammed in a staircase of 42 dams and reservoirs, although the 700 miles in the middle reaches of the Missouri River was a close runner-up. The results transformed the Tennessee Valley: rampant spring flooding ceased to afflict Tennessee farmland; improved navigation facilitated freight transport on the river to multiply sixty-seven-fold to 2.2 billion ton-miles in the thirty years leading up to 1963; electricity prices fell by more than half; farm yields multiplied on government-produced fertilizer; endemic malaria was eliminated; even the health of the river valley ecosystem was enhanced by the public reforestation of over a million acres. Tennessee River electricity also powered aluminum and war production factories for World War II, including the Oak Ridge atomic fission center, and brought farmers the first, wondrous benefits of electricity. In the early 1930s, American farmers had been left behind on the dark, Have-Not side of America's electricity divide. Only 10 percent of farms were electrified. By 1950, thanks chiefly to hydropower, 90 percent of U.S. farmers had access to illumination, refrigeration, radio, and the other productive, modern benefits of electricity.

Hundreds of huge dams were erected across the country during the apogee of America's giant dam-building age in the early postwar era. Through all U.S. history some 75,000 dams had been built-about one per day day from the end of George Was.h.i.+ngton's presidency to the inauguration of George W. Bush over 200 years later. Most of the 6,600 large ones over 50 feet, and all the multipurpose giants, were built after Hoover. For its seventy-fifth anniversary, the Bureau of Reclamation cataloged its c.u.mulative bureaucratic accomplishments: 345 dams, 322 storage reservoirs, 49 power plants marketing over 50 billion kilowatt-hours, 174 water-pumping plants, 15,000 miles of ca.n.a.ls, 930 miles of pipelines, 218 miles of tunnels, more than 15,000 miles of drains, irrigation water for 9.1 million acres, and freshwater for 16 million urban and industrial users. Farming in the arid Far West had not merely been born, but flourished as one of world history's all-time irrigated agricultural gardens. By 1978 the 17 western states had 45.4 million acres under irrigation-10 percent of the world's total. from the end of George Was.h.i.+ngton's presidency to the inauguration of George W. Bush over 200 years later. Most of the 6,600 large ones over 50 feet, and all the multipurpose giants, were built after Hoover. For its seventy-fifth anniversary, the Bureau of Reclamation cataloged its c.u.mulative bureaucratic accomplishments: 345 dams, 322 storage reservoirs, 49 power plants marketing over 50 billion kilowatt-hours, 174 water-pumping plants, 15,000 miles of ca.n.a.ls, 930 miles of pipelines, 218 miles of tunnels, more than 15,000 miles of drains, irrigation water for 9.1 million acres, and freshwater for 16 million urban and industrial users. Farming in the arid Far West had not merely been born, but flourished as one of world history's all-time irrigated agricultural gardens. By 1978 the 17 western states had 45.4 million acres under irrigation-10 percent of the world's total.

From the 1940s America was by far the most advanced hydraulic engineering civilization on Earth. As in past eras of history, this leaders.h.i.+p was reflected in both robust population growth and an even greater surge of available freshwater supply. American water use for all purposes multiplied tenfold, from 40 billion gallons per day to 393 billion gallons between 1900 and 1975. Population tripled in the same period. The more than tripling of freshwater use per person was a leading indicator and driving factor behind the country's rapid rise in living standards, national economic productivity, and preeminent global influence. America's intensive proficiency in every traditional category of man's use of water, and its pioneering leaders.h.i.+p in leveraging innovative water breakthroughs was a major reason why it was the best fed, healthiest, first fully electrified, most industrially productive, most urbanized, most transportation efficient, and most militarily powerful nation on Earth in the postwar decades.

Not all the upsurge in America's freshwater supply in the Far West derived from its innovative dams. From the mid1940s, the drought-p.r.o.ne western High Plains was transformed from a h.e.l.lish Dust Bowl into an irrigated cornucopia of grains by a sudden abundance of water drawn from an altogether different source-an immense, heretofore mostly inaccessible, aquifer that lay buried, like a sealed subbas.e.m.e.nt, deep beneath the near surface groundwater table underlying its semiarid landscape. Ogallala, or High Plains, water accounted for about one-fifth of total U.S. irrigated farming by the late 1970s, and in good years, up to three-quarters of the entire world's wheat crop that was sold on international markets. In addition, 40 percent of American cattle drank Ogallala water and ate Ogallala-watered grain-every ton of which required some 1,000 tons of water to grow.

The hydraulic secret of the arid High Plains was that running far underneath Nebraska, western Kansas, Oklahoma's Panhandle, northwestern Texas, and small portions of South Dakota, Wyoming, Colorado, and New Mexico was a giant honeycomb of up to half a dozen enclosed pockets of freshwater that together were the size of Lake Huron, and contained some 3.3 billion acre-feet, or over 235 years' flow of the Colorado River. The water was wedged between rocks and mixed with silt, sand, and stones. The deepest portion of the aquifer was in the north, so that overall about two-thirds of the water lay under Nebraska and 10 percent each in Texas and Kansas. Ogallala's "fossil water" was the drop-by-drop acc.u.mulation from prehistoric ice ages-one of the largest known subterranean reservoirs that existed deep inside the planet's bowels at varying depths. Around the planet there was up to 100 times more freshwater locked away in aquifers than flowed freely and readily accessibly on the surface. Such fossil aquifers existed like nonrenewable, stand-alone reservoirs insulated from the planet's continuous, natural hydrological recycling of surface and shallow groundwater through evaporation and precipitation. They recharged so slowly-Ogallala only half an inch per year from the trickle down from the surface-that they effectively could be used only once before depleting like an empty gas tank.

Due to water's great weight and the technological and cost limitations of pumping up water from aquifers, the High Plains's underground water wealth remained virtually untapped through the 1930s. Waterwheel-powered pumps were useless in an arid land without running streams to drive them, while the cost of transporting coal for steam pumps was prohibitive. Windmills could lift only a few gallons per minute and thus barely skimmed the surface of the Ogallala's deep reserves. The ranchers' prairie-gra.s.s-grazing cattle herds of the 1870s and 1880s had disappeared in the droughts and heat of the 1890s; with the return of the rains and demand for grain after World War I, farmers again ventured forth with their plow mules into the water-fragile frontiers beyond the 100th meridian. Then during the prolonged drought years of the 1930s came the man-a.s.sisted environmental catastrophe of the Dust Bowl. By clearing their land through cattle grazing and burning harvested wheat stubble, farmers inadvertently turned a fragile ecosystem into an unstable one. Without vegetation to hold the loose topsoil in place, the return of drought, heat, and high, gusting winds kicked up horrific dust storms that devastated farming across the western plains.

Dust storms were created when dry soil was lifted into the air by hot, high, winds; the resulting cloud of swirling, fine particulates grew larger and larger and gathered force as it swept across the open prairies. Eventually it became a gigantic cloud of stinging, shearing dust up to 10,000 feet high and reaching velocities of 60 to 100 miles per hour. The devastation wreaked by the dust storms was of biblical proportions: crops torn up and entire harvests lost, houses shorn of their paint and chickens of their feathers, dirt clogging mechanical farm equipment and water pipes, and millions of tons of fertile topsoil-the precious patrimony of the land-blown far away forever. In the duster that started on May 9, 1934, some 350 million tons disappeared, darkening the skies and dropping dirt residue over Chicago, Buffalo, Was.h.i.+ngton, D.C., Savannah, and even s.h.i.+ps sailing 300 miles into the Atlantic. Between 1935 and 1938 there were an average of more than 60 major, sky-blackening dust storms each year. In the heart of the Dust Bowl-a 400-mile-long by 300-mile-wide area encompa.s.sing parts of Oklahoma, Texas, New Mexico, Kansas, and eastern Colorado-the average acre was stripped of 408 tons of fertile topsoil, leaving behind pauperized, sandy earth. Some 3.5 million "Dust Bowl refugees" abandoned the Midwest in search of work by 1940. Many migrated west to pick crops in California, enduring the hards.h.i.+ps chronicled in John Steinbeck's cla.s.sic novel The Grapes of Wrath The Grapes of Wrath.

Even as the dust storms blew, the High Plains farmers' deliverance was at hand in the form of the centrifugal pump already being used with miraculously transformative effects in California's Central Valley to extract voluminous amounts from its own aquifer. With the postwar recovery and the availability of cheap diesel fuel from the nearby oil patch in Texas and Oklahoma, diesel-powered centrifugal pumps and water wells proliferated. A centrifugal pump could lift 800 gallons of water in only a minute, making widespread irrigation possible on the High Plains for the first time. Oil drilling techniques were also adapted that could raise water even faster. With the postwar invention of the center-pivot irrigation system-a long-tentacled, mobile sprinkler system hooked up to a water well-water pumping and irrigated farming boomed. With some 150,000 pumps extracting huge volumes day and night during the growing seasons, Ogallala annual water use quadrupled between 1950 and 1980, and irrigated acreage septupled to 14 million acres. By the late 1970s, intensified by modern petrochemical fertilizers, pesticides, herbicides, and generous farm subsidies, the 1 percent of American farmers working 6 percent of the nation's cropland that forty years earlier had been a desolate Dust Bowl, were growing 15 percent of that nation's wheat, corn, cotton, and sorghum.

But the boom couldn't last indefinitely. Farmers were drawing water out of the Ogallala 10 times faster than the aquifer network was recharging. Irrigation farmers were living on borrowed time and water. The most profligate drilling was in west Texas and other southern portions of the aquifer. One Kansas region that in 1970 thought it had reserves for 300 years discovered in 1980 that it had only a seventy-year supply left. Water that had acc.u.mulated over so many millennia, and acted like an emergency reserve of nature, would be consumed in a one-time irrigation bonanza lasting no more than a century unless it was conserved or used more productively. The prairie would revert to its natural, hardscrabble aridity, its agricultural bounty wither in a new cloud of dust.

Drawing America's groundwater patrimony for unsustainable food exports to foreign countries was a particularly shortsighted policy. From the late 1970s, drawdown allocation agreements and sharply increased pumping costs due to the era's oil price shocks, slowed the rate of depletion and encouraged irrigation efficiencies that got "more crop per drop." Yet the overdrafts-which by 2000 totaled 200 million acre-feet, or 14 Colorado Rivers-were highly concentrated in a few shallower, southern regions. Thus while sustainable equilibrium was being achieved in water-rich Nebraska, Texas and Kansas had already used up some 30 percent and one-sixth of their total shares, respectively, and were still overdrawing at a reckless pace. The looming storm cloud gathering over parts of the prairie was the question how long accessible water from the Ogallala reservoir would last. The day of reckoning for Texas and Kansas was expected to hit between 2020 and 2030.

Recognizing that the future of oil-built Texas depended upon securing enough freshwater, some Texan leaders schemed, and failed, in the late 1960s to steal a march on their regional neighbors by launching an outsized, technically complex, and extremely costly interstate Texas Water Plan to transfer flow from the Mississippi River and pump it across the state to the high plains of west Texas. Robbing one heavily used water ecosystem to replenish another offered no fundamental fix to the depletion challenge. But it did provide a foretaste of the extreme kind of political and resource compet.i.tion that lay ahead as parts of the Ogallala ran dry.

From the San Joaquin Valley in California's Central Valley and metropolitan Phoenix to El Paso and Houston, Texas, water tables in many arid regions were falling precipitously, causing land subsidence and salt contamination of drinking water and farmland. Despite the respite from California's great water-moving projects, unregulated overpumping in the Central Valley had resumed at such a furious pace that the groundwater tables had plunged up to 400 feet and the land itself had fallen 50 feet in some places. Even the rivers, lakes, wetlands, shallow groundwater, and interrelated water ecosystems of the country's rainy, eastern half were also under growing stress from the intense demands of population and industrial growth. In south central Florida, the straightening, damming, and redirection of streams to benefit the region's large sugar growers had disrupted the fragile Everglades wetlands, which were drying up and shrinking. As clean, fresh surface water became less available across America, groundwater resources were being overdrawn to make up the shortfall. In the thirty years leading up to 1996, total U.S. groundwater usage more than doubled to account for one-fourth of all U.S. water usage.

Although America was one of the world's most water-rich countries, with 8 percent of the world's replenishable freshwater but only 4 percent of its population, shortages of fresh, clean water were starting to impinge upon many regions' patterns of growth, fomenting a new politics of resource compet.i.tion among neighbors used to plenty. It wasn't that the country didn't have enough total total water to meet its needs. Rather it was that its profligate use was finally exhausting the productive limits created by the innovative successes of its age of giant dams. The era of cheap, plentiful water was closing. New technologies and more efficient usage were needed. As throughout water history, the success of one era was seeding the defining challenge of the next. water to meet its needs. Rather it was that its profligate use was finally exhausting the productive limits created by the innovative successes of its age of giant dams. The era of cheap, plentiful water was closing. New technologies and more efficient usage were needed. As throughout water history, the success of one era was seeding the defining challenge of the next.

America's age of great dams drew to a close during the 1970s. By then, virtually all the best large dam sites had been exploited. Hardly a major river flowed freely across America's landscape without being interdicted by dams and stored behind reservoirs. While the earliest dams from Hoover onward had returned the largest economic gains for the lowest subsidies, the later ones, by and large, had been built at the more marginal sites, carried the largest subsidies, and had hardly provided any net economic benefit at all. Yet even as the dam-building boom tapered off, demand for more freshwater and hydropower continued to escalate to meet growing populations, intensifying the political struggle among users to control a greater share of the limited, indispensable liquid resource.

The Colorado River told the tale. By 1964 an array of 19 large dams and reservoirs held four times the river's annual flow and gave man total management over the Colorado system. No longer did the river remotely resemble the wildly surging, unpredictably flooding river explored by John Wesley Powell almost a century earlier. Each drop was measured, every release calculated, and every event on the river planned by its central managers. It was the lifeblood of the entire southwestern United States. Every drop was used and reused 17 times before reaching the sea. As demand for its water increased, it also became the most litigated river in the world. By the 1950s Southern California was not only consuming its full 4.4 million acre-feet ent.i.tlement under the 1922 water sharing compact, but also was starting to take up to an additional 900,000 acre-feet of unused flow allotted to other states. A Supreme Court ruling in 1963 instigated by fast-growing Arizona, which feared California would claim a permanent right to the water that was otherwise part of its allocation, put a legal hold on California's water overuse-although the political showdown to make it practicable did not occur for another forty years. As the water needs of Arizona and other basin states increased toward their full allocations, something had to give.

The first to feel the squeeze was Mexico. During the 1950s an average annual 4.24 million acre-feet had flowed across the border into Mexico, which used it for irrigation and to replenish the lagoons of the river's lush delta. In the 1960s, the average flow plummeted to the 1.5 million acre-feet minimum ent.i.tlement under the 1944 treaty, and the river rarely again reached the sea. Deprived of water and silt, the delta ecosystem shrank into an almost lifeless, salt flat wasteland with a few strips of irrigated cropland. Worse still for Mexico, its 1.5 million acre-feet had become so briny as to be almost worthless for irrigation. The transformation of the Colorado by damming and intensive irrigation had also changed the river's composition as well as its volume. Sediment trapped behind the dams made the river much less silty. Irrigators could partly compensate for the loss of naturally refres.h.i.+ng silt flood deposits by intensive use of artificial fertilizers. But the drainage backflow of used irrigation water contaminated the river with high levels of salts leached from the cropland; by 1972, salinity at the river's halfway point had increased two and a half times over its natural, predam state. Salinity acc.u.mulations were highest downriver at the Mexican border. For more than a decade, the United States had rejected Mexico's protests that the 1944 treaty guaranteed it 1.5 million acre-feet of irrigation-quality irrigation-quality water. Then, in 1973, perhaps mindful of the discovery of large oil fields in offsh.o.r.e Mexico, American diplomats finally agreed to deliver water with an acceptable salt content. water. Then, in 1973, perhaps mindful of the discovery of large oil fields in offsh.o.r.e Mexico, American diplomats finally agreed to deliver water with an acceptable salt content.

While compet.i.tion for Colorado water intensified, the river's managers also made the awful discovery that the 1922 Colorado River Compact's baseline estimate of 17.5 million acre-feet per year had been much, much too optimistic. The eighteen-year streamflow data on which it had been measured covered an unusually wet period; by 1965 the Bureau of Reclamation knew that longer-term data suggested an average flow of only about 14 million acre-feet. Subtracting Mexico's 1.5 million and another 1.5 million for evaporation from the giant man-made storage lakes left only 11 million to be divided among states whose irrigation, hydroelectricity, and urban drinking water projects, when built to full capacity, depended upon receiving all the antic.i.p.ated 15 million acre-feet. The government-brokered compact simply promised more water than it could deliver.

The reckoning day for the Colorado water shortage was postponed by an extremely wet decade from the late 1970s and by reservoir draw-downs from Lake Mead and other storage facilities on the river. The full impact of overallocation finally began to be felt with the long drought in the first decade of the twenty-first century. The river's flow at the Compact's official delivery point from upper to lower basin states at Lee Ferry, Arizona, sank to its lowest level since measurements began in 1922. As Lake Mead, with its 28 million acre-feet capacity, drained to less than half full, water managers scrambled to develop emergency plans in the event it continued to sink below the level of Hoover's intake pipes. A growing body of long-term climate evidence from tree rings, moreover, suggested that the 1900s might have been a relatively moist century. A return to normal climate patterns thus would likely make the southwest even hotter and drier; another megadrought, like the speculated one that may have obliterated native farming civilizations early in the last millennium, was a possibility. Whether man-made or natural, the warmer weather in the Far West over the thirty years to the mid-2000s was already discernibly diminis.h.i.+ng Colorado water flows by reducing the winter mountain snowpacks and the replenis.h.i.+ng spring runoff it brought when it melted, while also increasing the evaporation loss from reservoirs. The prospect of chronic Colorado River water shortages menaced the basin's 30 million with economic slowdown, possible chronic water crises in large desert cities like Las Vegas and Phoenix, and chaotic political clashes for water among compact states and among metropolitan, industrial, and farm users within them.

The Colorado River shortages signified the dawning of a new Far Western water era marked by supply limitations and ecosystem depletions that demanded fresh responses including alternative technologies, conservation, organizational redeployment of scarce water resources, and new approaches to water management. One of the largest problematic legacies of successful irrigation of the arid west was the extreme economic misallocation caused by the lavish government subsidy for large farm businesses, which consumed over two thirds of the river water and whose runoff by far caused the greatest damage to underlying ecosystems. Such subsidies had served their original purpose in fostering western agricultural development, but long ago had outlived their usefulness. In California, four of every five farms were over 1,000 acres and 75 percent of the state's entire agricultural output came from just 10 percent of the farms. By the late twentieth century, vested agribusinesses had become privileged Water Haves who paid almost nothing for the region's scarce water, while more economically productive and water-efficient industries and cities were taxed by having to pay burdensome premiums of up to 15 to 20 times more to obtain enough. The efficient allocation mechanism of compet.i.tive market forces was being grossly distorted, with perverse impacts on economic growth, environmental resources, and basic fairness.

The end of the age of great dams in the United States occurred in the 1970s when an alliance of environmentalist, urban, and recreation industry lobbyists, armed with arguments proving the uneconomic returns of new large dams, united to gradually offset the overrepresentation of irrigation and dam interests in state and federal politics. The breakthrough event came in the late 1960s when the Sierra Club, founded in 1892 by naturalist John Muir and other Californians, rallied a national political effort to defeat proposals to dam the nationally hallowed natural wonder of the Grand Canyon. From then on, the national debate turned increasingly to offsetting the deleterious environmental by-products of dams, such as the drying up of deltas and wetlands, the heavy dependence they promoted on artificial fertilizers, pesticides, herbicides, and monoculture farming, the trapping of soil-replenis.h.i.+ng silt, the destruction of river wildlife-the Columbia River's 15 million wild salmon fishery had collapsed to under 2 million because the fish couldn't surmount the dams to return to their sp.a.w.ning grounds, for instance. By the late twentieth century, the main discussion about dams was their decommissioning and removal-indeed, in the United States decommissioning surpa.s.sed new construction by 2000.

America's antidam campaign had gained impetus from the vibrant, gra.s.sroots environmentalist movement that had sprung up in reaction to the mounting evidence that mankind was inadvertently poisoning itself with the detritus of industrial growth. Just as the large urban concentrations of the early nineteenth-century Industrial Revolution created foul sanitary conditions that threatened the habitability of large cities and produced the sanitary awakening, rapid industrialization produced unwholesome acc.u.mulations of unwanted industrial and agribusiness pollution of society's public waters, air, and soils that was midwife to the modern environmental movement. Over the decades surface freshwater rivers and lakes, seacoasts, and slow-moving, unseen groundwater ecosystems had grown increasingly contaminated. By the mid-twentieth century a new phenomenon-water pollution on a scale and intensity that overwhelmed natural ecosystems' restorative capacities-began to visibly threaten both public health and the long-term environmental sustainability of unfettered economic growth. Before World War II, the overwhelming proportion of pollution emanated from the smokestack technology cl.u.s.ter that burned fossil fuels and produced heavy metals like iron and steel. After World War II hundreds of new plastics, agricultural fertilizers and other synthetic chemicals-many extremely toxic and difficult for natural forces to degrade-became increasingly major pollutants.

For decades chemical companies dumped untreated toxic wastes into local rivers, ponds, and streams, where they leached into groundwater drinking sources and years later brought illness and death to uncounted thousands. By 1980 the United States had more than 50,000 toxic waste dumps. In one infamous incident, residents and schoolchildren in Love Ca.n.a.l, a neighborhood in Niagara Falls, New York, built on landfill atop a toxic waste dump site, suffered abnormally high rates of cancers and birth defects a generation later. The area was declared a disaster zone and evacuated. Similar horror stories emerged in other countries. j.a.panese children around Minamata Bay, for instance, showed brain damage after 1956 from eating fish contaminated by the mercury dumped years earlier by a local chemical factory. Islands of toxic waste as long as 18 miles long and three miles wide formed in the Soviet Union over one-mile-deep Lake Baikal, the world's largest freshwater lake. North America's Great Lakes, holding about 20 percent of Earth's fresh surface water, also showed the pollution from the heavy industrial activity around its sh.o.r.es; by the early 1960s much of Lake Erie's fish life had suffocated due to algae blooms run amok from fertilizer runoff and dumping of wastes. Similarly, a large part of the once rich Baltic Sea fishery had become biologically dead from northern Europe's heavy industrial sewage and chemical fertilizer effluents, above all those drained by communist Poland's filthy Vistula River. Acid rain caused by rising sulfur dioxide emissions from industrial smelters and burning fossil fuels contaminated freshwater sources and food chains across national boundaries; the sulfur dioxide emitted in a single decade in the late 1980s from Ontario's giant copper and nickel smelters alone was estimated to have exceeded the entire volume released naturally by all the volcanoes in Earth's history. Nuclear weapons production by the Cold War superpowers also polluted rivers and lakes in America and the U.S.S.R. with deadly radioactive waste.

If the modern environmentalist movement had a specific birth moment it came in 1962 with the publication of a seminal book, Silent Spring. Silent Spring. Written by Rachel Carson, a former U.S. government aquatic biologist, Written by Rachel Carson, a former U.S. government aquatic biologist, Silent Spring Silent Spring focused the national spotlight on the insidious, water polluting effects of synthetic chemical pesticides such as DDT that were widely applied to kill insects and improve crop yields, and drew attention to the larger ramifications it portended for what man was doing to his habitat. "The pollution entering our waterways comes from many sources: radioactive wastes from reactors, laboratories, and hospitals; fallout from nuclear explosions, domestic wastes from cities and towns; chemical wastes from factories," Carson wrote. "To these is added a new kind of fallout-the chemical sprays applied to croplands and gardens, forests and fields...our waters have become almost universally contaminated with insecticides." In vivid prose Carson, who had grown up on the banks of the Allegheny River near Pittsburgh and had witnessed firsthand the effects of industrial pollution from the coal-burning electric plants on the river's ecosystems, synthesized many scientific studies into the bigger picture. "The problem of water pollution by pesticides can be understood only in context, as part of the whole to which it belongs-the pollution of the total environment of mankind." focused the national spotlight on the insidious, water polluting effects of synthetic chemical pesticides such as DDT that were widely applied to kill insects and improve crop yields, and drew attention to the larger ramifications it portended for what man was doing to his habitat. "The pollution entering our waterways comes from many sources: radioactive wastes from reactors, laboratories, and hospitals; fallout from nuclear explosions, domestic wastes from cities and towns; chemical wastes from factories," Carson wrote. "To these is added a new kind of fallout-the chemical sprays applied to croplands and gardens, forests and fields...our waters have become almost universally contaminated with insecticides." In vivid prose Carson, who had grown up on the banks of the Allegheny River near Pittsburgh and had witnessed firsthand the effects of industrial pollution from the coal-burning electric plants on the river's ecosystems, synthesized many scientific studies into the bigger picture. "The problem of water pollution by pesticides can be understood only in context, as part of the whole to which it belongs-the pollution of the total environment of mankind."

Observing that for the first time in earthly history, mankind in the twentieth century had gained sufficient power to substantially modify the natural surroundings, Carson worried that it was using it recklessly, polluting air, earth, rivers, and seas in irreversible ways perilous to civilization's own survival. She concluded, "Along with the possibility of the extinction of mankind by nuclear war, the central problem of our age has therefore become the contamination of man's total environment with such substances of incredible potential for harm-substances that acc.u.mulate in the tissues of plants and animals and even penetrate the germ cells to shatter or alter the very material of heredity upon which the shape of the future depends."

The publication of Silent Spring Silent Spring immediately gave voice to the inchoate, gathering public concern about the environment. Almost overnight, the modern environmentalist movement became a potent political force. Big chemical companies, the U.S. Department of Agriculture and others with perceived vested interests in maintaining the short-term immediately gave voice to the inchoate, gathering public concern about the environment. Almost overnight, the modern environmentalist movement became a potent political force. Big chemical companies, the U.S. Department of Agriculture and others with perceived vested interests in maintaining the short-term status quo, status quo, like their counterparts in all eras, mounted a vigorous offensive against like their counterparts in all eras, mounted a vigorous offensive against Silent Spring Silent Spring. Carson's science, her professional credentials, and even her personal traits were a.s.sailed. Yet Silent Spring Silent Spring resonated deeply within countervailing const.i.tuencies of America's pluralistic democracy. President John F. Kennedy took a personal interest. Several expert federal and state studies were duly undertaken and corroborated her allegations. resonated deeply within countervailing const.i.tuencies of America's pluralistic democracy. President John F. Kennedy took a personal interest. Several expert federal and state studies were duly undertaken and corroborated her allegations.

Before the decade was out, the new environmental movement had gathered unstoppable momentum. Action was further galvanized by a number of high-profile environmental disasters. None was more influential than the spectacular, five story high flames that combusted on Cleveland's Cuyahoga River on June 22, 1969, from the sheets of unregulated, flammable wastes that had been dumped into the river. Within months, the United States took the regulatory lead by enacting comprehensive national environmental legislation and empowering the Environmental Protection Agency to execute it. The 1972 Clean Water Act, and the 1974 Safe Drinking Water Act, were pa.s.sed to cleanse America's surface and ground waters of pollution. Authorities began to tackle the immense problem of controlling intensive, algae blooms in lakes and coastal seash.o.r.es. Endangered species were protected. DDT and other harmful chemical pesticides were banned domestically, although not their export to third world countries.

The first annual Earth Day on April 22, 1970, rallied 20 million Americans to support an environmentally healthy planet; twenty years later, 200 million people in 140 countries turned out. Environmentalism went global in the late 1980s. The United Nations played a leading role, starting with the influential 1987 report "Our Common Future," known also as the "Brundtland Report" after its Norwegian chairwoman, that called for examining the relations.h.i.+p between economic growth and environmental sustainability. Thereafter it supported Earth Summits of heads of state every decade since 1992, an ongoing intergovernmental study of climate change from 1988, an influential commission on environmentally sustainable development in 1989, and the first comprehensive, five-year-long a.s.sessment of Earth's total ecosystems inaugurated on the occasion of the millennium in 2000 and completed in 2005. International environmental treaties covering environmental problems from air pollution to global warming also were signed by many countries. From the early twenty-first century, water ecosystems received special attention. The U.N. published its first triennial World Water Development Report in 2003 and in 2005 launched the International Decade of Water for Life. Providing clean water and a healthy environment increasingly became a standard measure for domestic legitimacy around the world; horrendous environmental disasters helped undercut the political credibility of the Soviet Union before its collapse and were increasingly becoming focal points of democratic protests in early twenty-first-century China. Giant industrial corporations, such as General Electric, gradually embraced environmentalist agendas and attempted to redefine their images and activities as eco-friendly. Sadly, Rachel Carson never lived to see her handiwork come to fruition. She died of cancer in 1964, at age fifty-six, less than two years after Silent Spring Silent Spring's publication.

The environmental movement represented a turning point in water and world history. For all human history, the governing view was that Earth's freshwater resources were essentially unlimited, naturally self-cleansing, and free to extract from its ecosystem without consequences in any amount of which man was capable. In its place, increasingly, a new recognition was emerging: that in order for industrial civilization, with its prodigious power to alter the natural environment, to continue to thrive it was necessary to establish a sustainable equilibrium between economic growth and its host water ecosystems.

America's pioneering giant, multipurpose dams were the instant envy of the world. Within only a few decades, foreign states everywhere were striving to replicate America's achievement. The result was a dam-building boom of epic proportions on virtually every major river of the planet. The resulting improvements in material well-being helped make communist states credible challengers to the postwar hegemony of liberal Western democracies, and allowed newly independent, poor countries, for the first time in history, to move up the industrial development ladder. Industrialized prosperity spread globally, transforming the world political economy and balances of power. By the end of the century, it had helped bring into existence a multiaxial, interdependent global order that was gradually superseding the long era of western European and U.S. hegemony.

For all countries, the cheap hydroelectricity and freshwater unlocked by large dams was a panacea-irrigation for increased food production, power for industrial factories, healthy drinking water, sanitation services and illumination for large metropolitan centers, and popular hope of betterment in material life. Dams transcended political or economic ideology. Whatever the system, dams meant prosperity, more stable societies and greater governmental legitimacy. American president Herbert Hoover's statement that "Every drop of water that runs to the sea without yielding its full commercial returns to the nation is an economic waste" was virtually interchangeable with Soviet Union leader Joseph Stalin's maxim that "water which is allowed to enter the sea is wasted." Every twentieth-century leader from Teddy Roosevelt to China's Mao Zedong would have concurred. At the dedication of north India's giant Bhakra Dam in 1963, an awestruck Prime Minister Jawaharlal Nehru echoed the rhapsodic Franklin Roosevelt at Hoover as he proudly likened the dam project to "the new temple of resurgent India." Both his sentiment and metaphor were strikingly similar to President Na.s.ser's comparison of Egypt's High Aswan Dam to a pyramid. To each and every leader, water seemed to be a potentially infinite, enriching resource of nature limited only by society's technical virtuosity in extracting ever more of it from the environment.

The centralizing, hydraulic society tendencies of dam-building conformed easily to the model of communist state planning. Marshaling an unpaid army of gulag laborers, Stalin began erecting dams on the Volga River in 1937, and thereafter built them on other great rivers including the Dnieper, Don, and Dniester. All across the huge nation, rivers were rerouted and lakes diverted to the design of Soviet water engineers and state industrial planners. With the help of giant dams, the Soviet Union increased its water use eightfold in the sixty years following the 1917 Bolshevik Revolution and rose to rival America as the world's leading superpower.

Aggressive dam construction and a.s.sociated water management likewise was a centerpiece of Chairman Mao's effort to reengineer Chinese society to communism in the postwar era. Given Chinese civilization's storied heritage of heroic state waterworks, China's communist mandarins took naturally to the opportunities of dam building on all its rivers, great and small. By the end of the twentieth century, China had some 22,000 large dams-nearly half the world's total and more than three times as many as America-helping to more than double irrigated cropland in the first quarter century of communist rule from 1949. In 2006 it officially opened the world colossus of all dams at Three Gorges on the Yangtze-China's Hoover, and linchpin of its bid for an accelerated economic transformation akin to America's conquest of its western arid lands.

j.a.pan's postwar economic miracle-and the largesse that kept the ruling liberal democratic party in power for so long-rested in part on the intensive exploitation of its limited arable land and its hydropower potential through the construction some 2,700 large dams on its mountain-fed rivers. India's 4,300 large dams ranked it third in the world behind China and America and were vital to its keeping pace in food production for its explosively growing postwar population. Almost every developing nation had its signature giant dam project that was the political and economic centerpiece of its society. As the Aswan Dam transformed the Nile, and with it, all Egypt, Turkey's giant, 1990 Ataturk Dam anch.o.r.ed its immense, region-transforming Southeastern Anatolia Project of 22 dams and 19 hydroelectric plants, while downstream on the Euphrates, the national dreams of Syria and Iraq hinged on there being enough water for their own giant dams. Pakistan's national pride was the huge Tarbela Dam on the Indus. Water-rich South America's stupendous, 1991 Itaipu Dam, on the Parana River on the Brazil-Paraguay border, held the t.i.tle as the world's largest generator of hydroelectricity-at least until Three Gorges. .h.i.t full capacity. Central Asia's Tajikistan inherited the world's tallest dam, the Nurek, at 984 feet, when the old Soviet Union broke up.

In all, by the end of the twentieth century mankind had built some 45,000 large dams; during the global peak of dam building in the 1960s, 1970s, and 1980s, some 13 were being erected on average every day. World reservoir capacity quadrupled between 1960 and 2000, so that some three to six times more water than existed in all rivers was stored behind giant dams. World hydropower output doubled, food production multiplied two and half times, and overall economic production grew sixfold.

The international dam boom facilitated one of the most dramatic physical man-made transformations of Earth-the rapid expansion of irrigated cropland, much of it far from natural riverbeds, often through the ferocious conversion of forests and wetlands. Abetted by the extensive mechanization of agriculture, irrigation nearly tripled in the half century after 1950 to cover about 17 percent of the world's arable land and produce 40 percent of its food.

Intensified application of water was a critical linchpin of the world-changing, twentieth-century Green Revolution, which spread from the West to produce surplus yields across the developing world from the 1960s and 1970s. The Green Revolution was based on breeding high-yielding strains of staple crops like corn, wheat, and rice that were highly responsive to intensive inputs of water and chemical fertilizer. One of the pioneering breakthroughs had been in hybrid American corn, starting in the 1930s. By the 1970s, virtually all the corn grown in the United States was hybrid, with yields averaging three to four times more than standard corn of the 1920s. Hybrid dwarf wheat, which carried many more grain seeds in its head than ordinary wheat, triggered its first Green Revolution in Mexico, then spread with spectacular results in the 1960s through the wheat belts of southwest Asia from India's Punjab to Turkey at the head of the ancient Fertile Crescent. Regularly at the brink of ma.s.s starvation, staved off only by ma.s.sive American food donations, India became self-sufficient in food following its 1974 adoption of hybrid wheat. From the late 1960s, hybrid dwarf rice took hold through the world's rice belt, from Bengal to Java to Korea. Between 1970 and 1991, hybrid varietals increased their share from under 15 percent to 75 percent of developing world wheat and rice crop, while yields multiplied by two and three times.

The Green Revolution was akin to other great agricultural revolutions that transformed world history, including the arrival of Champa rice in China in the eleventh century, the introduction of American maize, potatoes, and ca.s.savas to Europe and Asia after the European Voyages of Discovery, and Britain's successive, systematic Agricultural Revolutions from the late seventeenth to early twentieth centuries. Instead of ma.s.s starvation and political upheaval from the twentieth century's quadrupling of world population, world living standards per person ruptured from all historical trends and tripled. The global diffusion of wealth creation helped establish a new world economic order marked by an integrated web of fast-moving, cross-border exchanges of communications, capital, goods, ideas, people, environmental impacts as well as buffeting feedback loops. Goods moved around the world on an oceanic superhighway of intermodal container s.h.i.+pping to create a new phenomenon in which demand in any country could be met by supply produced outside its borders as readily as from within. By 2000, some 90 percent of world commerce moved by sea on some 46,000 giant s.h.i.+ps amid 3,000 major ports and through a dozen strategically vital straits and sea ca.n.a.ls. The stunning abundance of clean, cheap freshwater that became widely accessible through giant dams, motorized drills, pumps, and other advanced industrial technologies highlighted water's indispensability in this remarkable achievement of civilization.

Yet toward the end of the century, the global water cornucopia unlocked by the age of dams began to reach its limits and, as in America, peak out. A similar pattern of ecosystem depletions and limitations, yet on a much larger, planetary scale, was emerging. By 2000, some 60 percent of all larger river systems in the world pa.s.sed through dams and man-made structures. Most of the best hydropower and irrigation dam sites in the world were already being used. So much freshwater had been redistributed across Earth's landscapes in dams, reservoirs, and ca.n.a.ls over the twentieth century as to account "for a small but measurable change in the wobble of the earth as it spins," noted world water expert Peter Gleick. Like the Colorado, great rivers such as the Yellow, Nile, Indus, Ganges, and Euphrates no longer reached the sea much of the year, or did so carrying greatly diminished restorative water flows and sediment to their delta and coastal ecosystems. The deleterious side effects of protracted, intensive irrigation and inadequate drainage on soil pauperization through salinization, waterlogging, and silt erosion were everywhere in increasing evidence. Irrigated cropland that had provided such a spectacular growth in worldwide food production was being retired as fast as new irrigated land was developed-the historic net expansion of irrigated land had ended. As traditional surface resources ran low, more and more regions were mining groundwater for irrigation much faster than nature's water cycle could restore it-some 10 percent of world farming was unsustainable in the long run. Water tables were sinking and desertification was spreading on several continents. Many parts of the world were compounding the problem by poisonously polluting their freshwater supplies, as well as their coastal fisheries, with industrial waste and farm runoff.

At the dawn of the twenty-first century, a new water challenge was rising to the forefront to reshape world civilization, geopolitics, and governing hierarchies between and within societies-an impending famine of freshwater and the depletion of Earth's civilization-sustaining water ecosystems. What was happening was that for the first time in history, mankind's unquenchable thirst, whetted by voracious industrial demand, gargantuan engineering capacities, and sheer multiplication of human population and individual consumption levels, was starting to significantly outstrip many planetary ecosystems' absolute supply of readily accessible and renewable clean, fresh liquid water. Based on current usage trends, practices, and foreseeable technologies, it was doubtful there was enough freshwater returning to the Earth's surface in the natural water cycle of evaporation and precipitation to sustain the economic growth necessary for the developing world's billions to attain anything close to the levels of prosperity and health enjoyed in the West-and for a terrifyingly large percentage of humanity, there wasn't enough clean water to live healthy, natural lives at all. An explosive compet.i.tion for scarce water loomed. Many of the driest, most heavily populated, and dest.i.tute regions, already couldn't feed their populations and had little realistic hope of doing so soon. Even in parts of the world where freshwater was relatively abundant, growing shortages were triggering a new cycle in the age-old struggle to control regional water resources, and with it, new realignments of political and economic power.

The new era of freshwater scarcity was the by-product of the cla.s.sic historical cycle of resource intensification, population boom, resource depletion, and flattening or falling economic growth until the next round of intensification and growth increased accessible water supply and made more productive uses of existing, available water resources. In the twentieth century, populations had multiplied based partly on the one-time surge in water supply from the era's great hydraulic innovations. But now that water supply boom was peaking out, leaving behind populations in many parts of the world with greater material needs and expectations than resources to satisfy them. With human population projected to balloon 50 percent by midcentury, the second scissors blade was now ineluctably closing. The planet's supply of accessible freshwater, as presently managed, was insufficient to meet the demands of many of the world's mostly young, restive, and growing mult.i.tudes. Fresh, clean-and utterly indispensable-water, in short, was fast becoming a depleted global natural resource and the world's most explosive political economic problem.

PART IV.

The Age of Scarcity

CHAPTER FOURTEEN.

Water: The New Oil.

The challenge of freshwater scarcity and ecosystem depletion is rapidly emerging as one of the defining fulcrums of world politics and human civilization. A century of unprecedented freshwater abundance is being eclipsed by a new age characterized by acute disparities in water wealth, chronic insufficiencies, and deteriorating environmental sustainability across many of the most heavily populated parts of the planet. Just as oil conflicts played a central role in defining the history of the 1900s, the struggle to command increasingly scarce, usable water resources is set to shape the destinies of societies and the world order of the twenty-first century. Water is overtaking oil as the world's scarcest critical natural resource. But water is more than the new oil. Oil, in the end, is subst.i.tutable, albeit painfully, by other fuel sources, or in extremis can be done without; but water's uses are pervasive, irreplaceable by any other substance, and utterly indispensable.

The long sweep of history revealed that long enduring civilizations were underpinned by effective water control using the technology and organization methods of its time. Whether it was the irrigation ca.n.a.ls of ancient Mesopotamia, the Grand Ca.n.a.l of imperial China, the waterwheels and steam engine of early industrial Europe, or the giant, multipurpose dams of the twentieth century, societies that rose to preeminence responded to the water challenge of their ages by exploiting their water resource potential in ways that invariably were more productive, larger in scale, and unleashed larger usable supplies than their slower-adapting rivals. In contrast, unmet water challenges, a failure to maintain waterworks structure, or simply being overtaken by more productive water management elsewhere was a common factor of many of history's declines and collapses. Likewise, the economic productiveness and political equilibrium of today's advanced societies depends critically upon the robustness, security, and continuous innovative development of an interlinked array of giant dams, electric power plants, aqueducts, reservoirs, pumps, distribution pipes, sanitary sewage systems, wastewater treatment facilities, irrigation ca.n.a.ls, drainage systems, and levees, as well as transport waterworks including port facilities, dredgers, bridges, tunnels, and ocean-spanning s.h.i.+pping fleets. In the unfolding reality of the new millennium, water use and infrastructure are also at the heart of the interlinked challenges of food, energy shortages, and climate change dictating the fate of human civilization.

Today, at the beginning of the twenty-first century, there is hardly an accessible freshwater source or a strategically placed waterway on an economically advanced part of the planet that has not been radically, and often monumentally, engineered by man's prodigious industrial power. As world population continues to be propelled toward 9 billion by 2050, and with so many third world inhabitants starting to move up toward consumption and waste-generation levels of the one-fifth living in industrialized nations, demand for more freshwater is continuing to soar. Yet no new innovative breakthrough capable of expanding usable water supply on a large enough scale to meet the demand is anywhere evident on the horizon.

Over the past two centuries, freshwater usage has grown two times faster than population. About half the renewable global runoff accessible to the most populated parts of the planet is being used. Simple math, and the physical limits of nature, dictates that past trends cannot be sustained. Throughout history the ceiling of man's capacity to extract greater water supply from nature had been bounded only by his own technological limitations. Now, however, an additional, external obstacle has arisen to impose the critical constraint-the depletion of the renewable, accessible freshwater ecological systems upon which all human civilization ultimately depends. As a result a new application of water is emerging to join society's traditional four primary uses-the allocation of enough water to watersheds and related natural ecosystems to sustain the vitality of the hydrological environment itself.

The age of water scarcity consequently heralds the potential start of a momentous transition in the trajectory of water and world history: from the traditional paradigm based on centralized, ma.s.s-scale infrastructure that extracted, treated, and delivered ever greater, absolute supplies from nature to a new efficiency paradigm built upon more decentralized, scaled-to-task, and environmentally harmonious solutions that make more productive use of existing existing supplies. This transition is fomenting a new politics in the old equations between population sizes and available water resources in societies all over the world. New population-resource equilibriums eventually will be achieved within each society, water-poor and water-rich alike, through breakthroughs in efficiency and organization on the one hand, or stagnation in personal living standards and overall population levels on the other-and very likely some mixture of both. History suggests that it will be a tumultuous process, recasting social orders, domestic economic hierarchies, international balances of power, and everyday lives. Some regions are better placed than others to face the transition. With water demand continuing to outstrip soaring population growth and many planetary ecosystems being taxed beyond sustainable levels, more and more water-fragile nations were already being driven to the brink. supplies. This transition is fomenting a new politics in the old equations between population sizes and available water resources in societies all over the world. New population-resource equilibriums eventually will be achieved within each society, water-poor and water-rich alike, through breakthroughs in efficiency and organization on the one hand, or stagnation in personal living standards and overall po