Cadillac Desert (85 page)

Since there can be only one ultimate destination for the waste-water carried by the master drain—San Francisco Bay—the spectacle at Kesterson has infuriated many of the five million people who reside in the Bay Area. They may pollute the bay badly enough themselves, even if they do not admit it; but to have a bunch of farmers grown wealthy on “their” water, and subsidized by their taxes, sending it back to the bay full of toxic wastes, selenium, boron, and salt—that is intolerable. The farmers—who have been stuck with much of their toxic runoff since Kesterson was closed—might reject such reasoning as simplistic and emotional. But the fact is that the people of the Bay Area appear to have the political clout to prevent the drain from ever reaching there, and they seem determined to use it. It matters little that the salts in the wastewater (the selenium and boron and pesticides are another matter) would hardly affect the salinity of a great bay into which the ocean rushes every day. What matters is that the San Joaquin Valley farmers asked for water and got it, asked for subsidies and got them, and now want to use the bay as a toilet. To their urban brethren by the ocean, living a world apart, all of this smacks of a system gone mad.

The one irrigated civilization of antiquity that remained intact for thousands of years was Egypt, and we are now reasonably certain why. Every year, the Nile, the world’s most reliable river, would engorge itself in a spring flood and cover most of Egypt’s agricultural land. The floods would both carry off the salts and deposit a fresh layer of silt. The farmers would then rush to plant their crops, which grew lavishly on the residual moisture and the perfect soil. In the 1960s, however, the Egyptians, pumped up with a sense of grandiose destiny by Gamal Abdel Nasser, decided to build a high dam on the Nile at Aswan. The Soviet Union helped them do it against the United States’ advice. The result has been described as the worst ecological mistake committed in one place by mankind. The spring floods are gone; the nutrient-rich silts no longer come; the Nile sardine fishery in the Mediterranean is going extinct; bilharzia, or schistosomiasis, a gruesome disease borne by a snail that thrives in slack waters in Africa, is rampant; the reservoir is silting up quite rapidly due to erosion from primitive agriculture upriver; irrigation canals, meanwhile, are being scoured by the silt-free water released by the dam; and the salts have arrived. With their copious new supply of year-round irrigation water, the Egyptian farmers have been irrigating madly, and the water table, increasingly poisoned by salts, is rising dangerously. Recently, Egypt hired a group of American engineers and agronomists, among whom was former Reclamation Commissioner Floyd Dominy, to help them figure out a solution. “Goddamned crazy Russians” was Dominy’s response when I asked him what things were like over there. “Anyone should have seen that Egypt wouldn’t be able to handle the effects of that dam.” The Egyptians now have no choice other than to install drainage, which they can ill afford—partly because schistosomiasis has become a national epidemic costing them some $600 million a year. The hydrologic engineer Arthur F. Pillsbury, writing in Scientific American in 1981, noted that Egypt, having avoided the fate of its sister civilizations all these centuries, “is now faced with the universal problem of keeping salts from accumulating in the irrigated fields.”

In that same article, Pillsbury also wrote:

In order to maintain and ensure the long-term viability of irrigated agriculture and to provide enough water to carry the salts to the ocean or some other natural sink, the development of water resources
should be intensified....
Before man began harnessing the rivers, the seasonal floods were highly effective in carrying salts to the ocean and keeping the river basin in reasonably good salt balance. Today, with river flows being regulated by storage systems, and with high consumptive use of the released water, there is not enough waste flow left to achieve anything approaching balance. The salt is being stored, in one way or another, within the river basins.... Unless the lower rivers are allowed to reassert their natural function as exporters of salt to the ocean, today’s productive land will eventually become salt-encrusted and barren.

In the end, Pillsbury concluded, there is only one answer. “Eventually, some grand-scale water diversion concept will be needed....”

I
n 1946, after participating in a conference involving twenty-four eminent hydrologists and engineers, Dr. Charles P. Berkey had a moment of epiphany. Berkey was, at the time, one of the foremost hydrologists in the world. Newbury Professor Emeritus of Geology at Columbia University, he had been a consultant to the city of New York on its Catskill and Neversink water supply projects, and had a list of accomplishments and credentials four times as long as his arm—a list which had kept him so busy he never had a chance to contemplate the implications of his life’s work until he was well into advanced age. Then it came to him—a sunburst of perception, a giant semantic leap.

What prompted Berkey’s enlightenment was a talk delivered at the conference by J. C. Stevens, then the president of the American Society of Civil Engineers. Berkey was so dumbstruck by what Stevens had to say that he drafted a response as soon as he got back to his desk at Columbia—a response which reads more like a confession of blindness or an admission of personal failing than anything else. This is part of what he had to say:

Although the principles involved in the paper by Mr. Stevens are well known, it is not certain that the implications are fully appreciated by many even in responsible relation to them. The Factual Data had been long known to the writer, but no statement before this one had brought so forcibly to mind their importance and bearing on long-range planning.... The United States has virtually set up an empire on impounded and redistributed water. The nation is encouraging development, on a scale never before attempted, of lands that are almost worthless except for the waters that can be delivered to them by the works of man. There is building up, through settlement and new populations, a line of industries foreign to the normal resources of the region...

Effort to use water on desert lands is not a new adventure by any means; but a program involving development of a great region—inviting thereby a large new population under conditions that carry elements of certain future destructive encroachment in limited and computable time—that is new. Not only is it new, but in some of the implications it is fairly astonishing.... The nearest thing in that respect was the settlement of the western high plains in earlier days by people who believed that these dust-bowl lands could be farmed in the same manner as those they came from in the Central Mississippi Valley, and no voice was raised to warn them. That was to be a vast and prosperous empire, too.

For the first time, after reading this paper, the long-range significance of the suffocating effect produced by accumulating silt in all these reservoirs was borne down on the writer. He had been so much taken with the fine things being done that he had not fully appreciated the fact that the program carried elements of destruction sure to bring some kind of ending. It was always evident, of course, that there were severe limitations, but it was too easy to overlook or belittle this element of damage from within.

The experience of founding, in difficult surroundings, settlements which finally grew into influence and power is not new; and neither is their decline, and even their ending. In the past, however, none of them carried, along with the agents that built them up, such relentless elements of destruction as in the present reclamation of arid lands. The astonishing thing is that the life of these relief works promises to be so short. One could forget it if the time vista were indefinite, or if there were promise of a thousand years. In that time most human subsistence and economic lines take new turns and become adjusted; but in some of these projects, typical of the average more or less, the beginnings of decline loom already and will certainly grow into a serious problem in three or four generations. One wonders how many settlers gathering around these projects appreciate what it means.

Of course, if one is able to divorce his interest from the future, there is nothing to worry about. In this generation, and the next and the next, an upgrade can be maintained. One can claim (and it is true) that much has been added to the world; but the longer-range view in this field, as in many others, is threatened by apparently incurable ailments and this one of slowly choking to death with silt is the most stubborn of all. There are no permanent cures.

The conference Berkey and Stevens had attended, “The Future of Lake Mead and Elephant Butte Reservoir,” was, more precisely, a summit meeting on the subject of mud. Before Hoover and Elephant Butte dams were built, the Rio Grande and the Colorado River ran chocolate-brown in the spring and anytime a cloudburst occurred somewhere in the watershed. Now, the water emanating from the penstocks and spillways below the dams was an opalescent blue-green, colored only by the minerals and algae in it. Each year, millions of cubic yards of silt were coming to a dead halt behind both dams.

For all their breathtaking immensity, dams are oddly vulnerable things—a vulnerability that is shared and greatly intensified among the millions of people who depend on them. The engineers who have built them have gone to great lengths to make them safe from earthquakes, landslides, and floods. But their ultimate vulnerability, as Berkey wrote, is to silt. Every reservoir eventually silts up—it is only a matter of when. In hard-rock terrain with a lot of forest cover—the Sierra Nevada, the Catskill Mountains—a dam may have a useful life of a thousand years. In some overpopulated nations whose forests are nearly gone and whose farmlands are moving up mountains and whose rivers are therefore thick with silt, reservoirs built after the Second World War may be solid mud before the century is out. The Sanmexia Reservoir in China, an extreme case, was completed in 1960 and already decommissioned by 1964; it had silted up completely. The Tehri Dam in India, the sixth-highest in the world, recently saw its projected useful life reduced from one hundred to thirty years due to horrific deforestation in the Himalaya foothills. In the Dominican Republic, the eighty-thousand-kilowatt Tavera Hydroelectric Project, the country’s largest, was completed in 1973; by 1984, silt behind the dam had reached a depth of eighteen meters and storage capacity had been reduced by 40 percent. In countries suffering from over-population, deforestation, which is the primary cause of reservoir siltation, can only be expected to grow worse.

As a matter of principle, any place where vegetation is relatively sparse, where soils are erodable, but where six inches of rain in a day or twenty inches in a month are not unknown is a less than ideal place to situate a dam. Those conditions, however, apply to a large part of the intermountain West—and, since the arrival of intensive agriculture, to a great portion of the Middle West as well. The Eel River in California is the most rapidly eroding watershed in North America—partly because the topography is ridden with erodable sediments, partly because of rampant clear-cutting earlier in the century from which the forests may never recover, partly because of stubble grazing by cattle and sheep that is still going on. There is no major dam on any branch of the Eel—at least not yet—but talk of building one there says a lot about what people are willing to ignore. Meanwhile, erosive forces are hard at work in the watersheds of the Missouri River, the Colorado, the Rio Grande, the Platte, the Arkansas, the Brazos, the Colorado of Texas, the Sevier, the Republican, the Pecos, the Willamette, the Gila—rivers on which there are dozens of dams.

Earlier in the century, it was thought by some that irrigation in those watersheds might actually slow the rate of erosion by creating more groundcover to hold the soil in place. In the 1920s, however, no one foresaw interest rates so high that farmers, pushed to the brink, would almost be forced to abandon careful husbandry of the soil for maximum profit. No one foresaw cheap fertilizers that allow land to be plowed year after year, never going fallow. No one foresaw six-ton tractors that tear up the soil and make it more apt to be carried off. No one foresaw a demand for U.S. agricultural exports that makes it profitable to farm Class VI land. As a result of all this—and because it was inevitable anyway—the dams are silting up.

Black Butte Reservoir, Stony Creek, California. Capacity in 1963: 160,009 acre-feet. Capacity in 1973: 147,754 feet.

Conchas Reservoir, Canadian River, New Mexico. Capacity in 1939: 601,112 acre-feet. Capacity in 1970: 528,951 acre-feet.

Alamagordo Reservoir, Pecos River, New Mexico. Capacity in 1936: 156,750 acre-feet. Capacity in 1964: 110,655 acre-feet.

Lake Waco, Brazos River, Texas. Capacity in 1930: 39,378 acre-feet. Capacity in 1964: 15,427 acre-feet.

Elephant Butte Reservoir, Rio Grande River, New Mexico. Capacity in 1915: 2,634,800 acre-feet. Capacity in 1969: 2,137,219 acre-feet.

Hoover Dam, Colorado River, Arizona-Nevada. Capacity in 1936: 32,471,000 acre-feet. Capacity in 1970: 30,755,000 acre-feet.

San Carlos Reservoir, Gila River, Arizona. Capacity in 1928: 1,266,837 acre-feet. Capacity in 1966: 1,170,000 acre-feet.

Howard Brothers Stock Dam, Driftwood Creek, McDonald, Kansas. Capacity in 1959: 26.58 acre-feet. Capacity in 1972: 14.18 acre-feet.

Ocoee Dam Number 3, Ocoee River, North Carolina. Capacity in 1942: 14,304 acre-feet. Capacity in 1972: 3,879 acre-feet.

Guernsey Reservoir, North Platte River, Wyoming. Capacity in 1929: 73,810 acre-feet. Capacity in 1957: 44,800 acre-feet.