Unleash the Rivers

By Marc Reisner

Last year, when a group of journalists and historians offered a list of the 100 biggest news stories of the 20th century, the Beatles' appearance on the Ed Sullivan Show was ranked 58th. Completion of Hoover Dam didn't make the cut. You sort of expect this from celebrity-infatuated mass culture: when it comes to fundamental achievements that make contemporary civilization work, a stifled yawn. Water, dams, aqueducts, irrigation, hydroelectricity--how borrrrrrring! Really? Los Angeles, world headquarters of celebrity culture, has measured as little as 5 in. (13 cm) of rainfall in a year. And despite occasional monsoons, Southern California is so chronically arid that it couldn't sustain a third of its current population without sucking billions of liters a day out of Lake Mead, the distant Colorado River reservoir formed by Hoover Dam.

One would think the creation of modern Los Angeles, which is what Hoover Dam allowed, would make that structure newsworthy. Actually, its historic significance is of more cosmic proportions. The first of the world's great dams, Hoover inaugurated an Age of Dams, which has spanned the past three-quarters of a century. The dam-building mentality has pretty much expired in the U.S.--one reason is, we've run out of dam sites--but it's still prevalent throughout much of the world. In China, which is erecting the Three Gorges Dam, the biggest (and, at $25 billion, the most expensive) hydroelectric project in history, one senses outright resentment against rivers running free.

Almost everyone has some appreciation of how water projects have altered the course of civilization in ways we (perhaps foolishly) call benign. Dams and reservoirs permit unimaginable numbers of people to inhabit forbiddingly arid regions--as well as floodplains where cities would be washed away without upstream protection. Sacramento, Calif., for example, is dryer than North Africa, but the Sacramento River, on whose banks it sits, spread 30 miles (50 km) wide during the wettest California winter on record, in 1862, before dams and levees tamed the river. Dams produce more clean energy than nuclear reactors. Irrigation agriculture, largely dependent on reservoirs, grows 40% of the world's food on a much smaller fraction of its farmland.

What we're just beginning to understand is how water development has, like nuclear energy, amounted to a Faustian bargain between civilization and the natural world--which, as it happens, supports civilization. Hydroelectricity from Grand Coulee Dam in Washington State smelted enough aluminum during World War II to build tens of thousands of warplanes, with enough surplus power to make plutonium for the first atom bombs. But now, in the form of devastated salmon fisheries, Grand Coulee (along with countless other dams) is extracting an awful price for its creation.

It seems ironic that nuclear energy is widely regarded as a greater environmental threat than dams, even though fission--with the jarring exceptions of Chernobyl and Three Mile Island--has caused relatively little harm. There may be huge calamities in its future, and its fiercely toxic fission products still have no demonstrably safe burial place. But dams, for all their material blessings, are responsible for some of the worst environmental tragedies in history.

In Central Asia, The Aral Sea, originally only somewhat smaller than Lake Superior, has shrunk to less than half its former size since the 1960s. The two big rivers that used to replenish it, the Amu Darya and Syr Darya, are now ceaselessly diverted to irrigate millions of hectares of cotton in Uzbekistan. Inspired by Joseph Stalin, this grand-scale hydrologic theft continues despite the dissolution of the Soviet Empire. It has destroyed one of the world's richest inland fisheries; abandoned boats rust 50 miles (80 km) from the sea's latest shoreline. Dust storms, poisoned by heavy metals and pesticides that washed into the disappearing lake, have combined with diseases that flourish in withered, polluted rivers to create a public-health catastrophe.

It's increasingly obvious that one of the worst features of communism was a relentlessly thuggish assault against nature. ("Let the Aral Sea die a beautiful death," a Soviet planner proclaimed in 1987. "It is useless.") But in the realm of water, the record of democratic capitalism, especially during the cold war, wasn't much better. As environmental tragedies go, the destruction of the Columbia River salmon fishery in the American Northwest runs a close second to the ruining of the Aral Sea.

When the first of the big Columbia dams (there are dozens on the main river and its larger tributaries, nearly all of them built by the U.S. government and public water agencies) were being erected in the 1930s and '40s, salmon was much cheaper than hamburger. The workers building the dams groaned when they saw the orange-hued fish on their dinner plates; some demanded contracts that limited salmon meals to three a week. This was wild salmon; today's piscine feedlots, where millions of genetically enfeebled, antibiotic-dependent, instinct-defunct salmon are raised in giant pens off the Chilean, Scandinavian and Canadian coasts, were someone's Orwellian fantasy.

Of all the salmon rivers on Earth, the undammed Columbia was the most productive. About 10 million to 15 million adult salmon swam upriver from the ocean to spawn in an ordinary year. But Grand Coulee, an impassable bulwark 550 ft. (170 m) high, forever closed off the upper watershed, about 40% of the ancestral spawning habitat. Salmon whose ancestors ran up tributaries that branch off below Grand Coulee--the Deschutes, the White Salmon, the Snake--can labor up fish ladders around smaller dams, but sooner or later they run into a dam too imposing to get around. The highest functional fish ladders are 100 ft. (30 m) tall; some tributaries are blocked by dams hundreds of feet high.

Logging, livestock grazing and diversions for irrigation have wrecked a lot of spawning habitat, but dams take the greatest toll, especially on minnow-size juvenile salmon. Rather than rush downriver on icy snowmelt, the just hatched smolts now drift into warmed, turbid reservoirs, where they are gobbled by hordes of predators. If they avoid being eaten, the dam turbines, with their crushing water pressure, lie ahead.

From a batch of 1,000 fertilized wild eggs, a single fish, on average, now survives to adulthood at sea. Almost $4 billion has been spent on Columbia restoration programs in the past two decades, but most of the West Coast salmon fishery south of Canada--not just the Columbia's--is heading for extinction, according to prominent biologists.

Another dismally awe-inspiring legacy of our 20th century obsession with water development has been the gradual disappearance of southern Louisiana. When the first irrigated civilizations were appearing in contemporary Iraq and Pakistan about 5,000 years ago, the Gulf of Mexico was roughly where New Orleans now sits. The Gulf, like all the other seas, had been rising since the last Ice Age, but the Mississippi River dumped 18 billion truckloads of sediment at the Gulf's door in the time it took the seas to rise a foot. It was (and still is) one of the planet's most dynamic contests between land and water.

Until just a few decades ago, land was winning. By the time of the Louisiana Purchase, the Gulf had retreated some 60 miles (100 km) south of New Orleans. The Mississippi's immense burden of flaked-off topsoil (originating mainly from its big western tributary, the Missouri) overmatched the rising Gulf. The unrestrained river episodically changed course, laying new land from Biloxi to Houston. Over 7,000 years, the Mississippi River created a new piece of continent the size of New Jersey.

Then, in the late 1920s, after a flood that spread the river 40 miles from its banks, the U.S. Congress made levee construction Washington's responsibility. Billions of tax dollars from elsewhere--probably tens of billions, in modern money--were spent constricting the Mississippi's channel, so its silt began washing straight out to sea and off the continental shelf. By the 1970s, more than half the historic sediment load was coming to a dead stop behind dozens of upriver dams--especially seven monstrous structures erected on the Missouri.

In just three or four decades, we had managed to reverse one of nature's most remarkable geomorphological phenomena. By the 1980s coastal Louisiana, instead of expanding in size, was disappearing under the Gulf at a rate of nearly 40 sq. mi. (100 sq km) a year. (The rate of land loss has declined somewhat since then; no one seems sure why.)

The lower Mississippi is the greatest freshwater coastal marshland in North America, a resplendently prolific nursery for fish, shellfish, furbearers and reptiles and a wintering haven for a third of North America's waterfowl. The saltwater invasion has cost the Cajun economy, rooted in fishing and trapping and hunting, dearly. But payment will soon be demanded farther north. Hydrologists are now proposing formerly unthinkable ideas--such as breaching the levees from New Orleans to the river's mouth--if only to spread enough silt to slow the Gulf's encroachment on the city. Even if that's done (it would probably cost New Orleans its port), it's hard to believe the Missouri dams will be removed, so the land loss will go on. Pieces of Plaquemines Parish might remain above water a few decades longer. Ultimately, as the Gulf closes in, New Orleans--which is below sea level, abjectly dependent on levee protection--could find itself awash in the storm surge of a major hurricane.

In ways direct and indirect, playing God with water has had a tendency to bite us back. In the 1970s and '80s, Brazil went mad for Amazonian dams, which don't so much electrify the countryside as feed industrial power into chaotic human hives like Sao Paulo. And although irrigation has helped countries with high birthrates avert hunger, it has reintroduced the hoary nemesis that played a big role in the downfall of Mesopotamia and Babylon: the salting out of the soil.

River water is much more mineralized than rainfall, and long desert rivers like the Tigris and Colorado are especially salty. Irrigating a hectare of cropland for one year can leave several tons of salts dispersed in the soil. In her recent book Pillar of Sand, Sandra Postel, a senior fellow with the Worldwatch Institute, cites astonishing figures concerning salt-burdened land: 7 million acres (3 million hectares) damaged in India, more than 6 million in China, more than 4 million in Pakistan. Moscow University's Victor Kovda, an authority on desert agriculture, calculated that more land has recently gone out of production because of salt and associated problems than has come into production through irrigation.

If the Age of Dams has been little more than ephemeral rescue, a denial of nature's limits--a cure in many cases worse than the disease--then what's the alternative on an overcrowded planet?

Water conservation is the only hope--and every person in the industrialized world wastes plenty of it. Even on the usually rain-drenched East Coast of the U.S., reservoirs get alarmingly low from time to time. People can help by using low-flow toilets, taking shorter showers with water-saving nozzles, washing cars less often and not soaking their lawns. But much more water is squandered by agriculture, and that's where the largest saving will have to come from.

Fortunately, progress is possible. Israel pioneered drip-irrigation systems, which deliver water to individual plants instead of spraying it in plumes over fields. Postel points out that small-scale water development can pose fewer and less vexing problems than megaprojects like China's Three Gorges. In some poor nations like Bangladesh, human-powered irrigation devices, such as treadle pumps, are becoming commonplace.

But even if conservation ends the need for new dams, what can we do about the destructive legacy that the Age of Dams has left behind?

One disarmingly simple answer--the U.S. has already done this with public housing--is to dismantle some of what was built. Grand Coulee Dam won't be demolished in any living person's lifetime, but removing a number of small dams--especially on salmon rivers--seems to make good sense, even in economic terms. In the coming age of alternative energy produced by wind turbines and solar cells, we can cut back on hydroelectric power.

From California to Maine, dam removal has begun. When four small diversion dams were taken off a Sierra Nevada stream called Butte Creek, record numbers of spring-run Chinook salmon--listed by the U.S. as a threatened species--rushed past their ruins to spawn. If the spring-run Chinook ends up on the more serious endangered-species list, that will trigger more restrictions on diversions from its spawning rivers. So helping the spring-run by getting rid of a few dams could be worth billions to California's economy, which is hopelessly dependent on the manipulation of water.

Unfortunately, no simple solution is politically simple. There's usually fierce resistance from local stakeholders to any proposal to remove a dam, no matter how small. But it's striking how, in just two or three decades, the U.S. has gone from building dams to not building dams to taking some of them down. Under serious discussion is the demolition of four brutish structures on the lower Snake River that have macerated millions of young fish.

We now seem much more captivated by the magic of a salmon's returning to its birthplace to spawn than by the miracle that obsessed our forebears: making deserts bloom. How to replenish water-dependent nature while meeting the demands of water-dependent society is going to test our ingenuity and will. Let's hope they won't be overtaxed.

Reisner, who has just been named a Pew Marine Conservation Fellow, is the author of Cadillac Desert