The Emerald Mile: The Epic Story of the Fastest Ride in History Through the Heart of the Grand Canyon (43 page)

S
hortly after lunch break the following afternoon, the foreman of
the dam’s maintenance department summoned his crew together for a quick huddle. Leon Suave’s group wasn’t big—they rarely had more than six or seven men—and they were responsible for a range of duties that ran from the exciting to the banal. If you worked for Suave, you might find yourself starting off the workweek pulling components from one of the generators in the power plant using the three-hundred-ton overhead crane. By Friday, you could be scrubbing out a clogged toilet in the visitors’ center or scraping up the remains of a civet cat that had accidentally incinerated itself in the switching yards. (The dam had a real problem with civet cats, long-tailed desert mammals that liked to plunder the eggs of birds nesting in the switching yards; if a civet was unlucky enough to pause atop a sixty-nine-kilowatt transformer while putting its paws on a conductor, the cat would literally explode.) On any given day, Suave’s crew encountered things that went quite a ways beyond the average maintenance person’s duties. But the orders he issued on Monday afternoon left even the veteran members a bit mystified.

“I want most of you guys to get up to the warehouse and start grabbing all the angle iron you can find,” Suave told his crew in a tone that demanded this happen immediately. “The rest of us need to start calling up lumberyards—we’re gonna need to round up every piece of marine-grade plywood we can get our hands on.”

Richard Parsons was one of the men on the angle-iron crew, which rushed over to the dam’s warehouse and started to cut lengths of two-inch steel into
four- and eight-foot pieces with a torch, then loaded them onto the back of a truck that began shuttling loads to the radial gates at the top of the dam. Meanwhile, the rest of the team raced in to Page and bought up every piece of three-quarter-inch plywood in town.

As they completed these tasks, Glen’s other crews were also mobilizing. While a team of electricians set up service lights on the bridge over the tunnel intakes, the dam’s high-scalers rigged a safety system along the tops of the two sets of spillway gates. This was tricky. The tops of the gates were more than two feet wide, which was plenty of room to move about; but the consequences of a misstep would be severe. On the downstream side loomed the fifty-two-foot drop to the sloping channel and the mouth of the tunnel. On the upstream side was the reservoir, where the water was nearly five hundred feet deep. Knowing that time was of the essence, the high-scalers strung a single safety line across the top of the gates, then hastily tethered a dozen life jackets on the reservoir side.

By sunset, everything was in place, and
Henry Dhieux, the foreman of the mechanics crew, summoned his five welders. Together they would tackle the most hazardous part of this job.
“Let’s grab our gear, get out on those gates, and tie off,” ordered Dhieux (whose name was pronounced
Dewey
). “We’re gonna start welding up some braces.”

When Dhieux’s team was in position with their rods and hoods, the maintenance crew began lowering sections of angle iron to the welders, who affixed a line of L-shaped supports to the tops of the gates. Onto those supports they framed up a bottom rail and a top rail to create the skeletal frame of a four-foot-high breastwork that ran all the way across. Then it was time for the plywood. Each sheet was tied off and carefully lowered by hand, with care taken to avoid knocking off the welders, who laid the pieces lengthwise, butted them end to end, and bolted them onto the supports.

As one hour bled into the next, the pace never slackened. Although they had by now raised the spillway gates slightly to provide a bit of freeboard, the water was inching inexorably closer to the tops of the gates. Then, shortly after midnight, the wind came up and the surface of the lake grew agitated. Every few minutes, a wave would slap against the gates, forcing Dhieux and his men to raise their welding leads above their heads to keep from being electrocuted. In the midst of one of these splashes, Dhieux accidentally knocked his helmet off the gate and watched it go skittering down the dark channel and into the mouth of the spillway. As he turned back to his work, he spied a school of carp that had been drawn across the lake by the string of service lights. The carp were hovering in the water less than an arm’s length away, little orange zeppelins with papery fins whose shivering undulations mirrored the strange and
invisible currents of the reservoir. He stared at them for a moment, fascinated by their ghostly forms. Then he returned to the brace he was welding and sent a furious fantail of hot, blue sparks arcing into the darkness.

The teams worked straight through the night, and when the welders finally untied and climbed away from the gates at 4:45 a.m., just before dawn, the spotlights illuminated a wall of flashboards extending across the tops. When they lowered the gates to prevent the reservoir from flowing into the spillway tunnel, jets of lake water were spurting between every crack and seam.

As a watertight barrier, the flashboards were cartoonishly inept, a jerry-rigged patch that appeared to have been cobbled together by a band of amateur carpenters and shade-tree mechanics. But that didn’t matter because, despite the leaks, the flashboards had effectively raised the upper edge of a nine-trillion-gallon swimming pool by four feet. In a single stroke, Gamble and his men had expanded the capacity of Lake Powell by conjuring roughly 645,000 acre-feet of additional storage space out of thin air.

Everyone was too exhausted to note that this marked an unusual moment in the annals of hydroelectric engineering. The Bureau of Reclamation, the world’s premier dam-building agency and a colossus of cutting-edge technological know-how whose resources and budget exceeded the GNP of several small countries, had temporarily stemmed the flood crest of the greatest river in the Southwest with a makeshift fortress of
plywood
.

T
he fix had bought the dam’s operators some desperately needed time, but a host of new problems were now popping up all over the dam, the first of which started the moment they opened up the river outlets, the four steel tubes running through the interior of the dam that bypassed water around the power plant.
Within hours, the outlets’ expansion joints were leaking, creating enough pressure to pop several
manhole covers in the parking lot next to the machine shop and drive the concrete slab around them more than two inches into the air. A galvanized-metal shed where the maintenance crew stored their supplies also
heaved upward and began to tilt. When the crew unbolted the manhole covers to see what might be causing this movement, a column of water came whooshing out like that from a fire hydrant lopped off by a runaway truck.

Gamble had no choice but to order the river-outlet works shut down so the couplings could be repaired, a job that would take two or three days. During that interval,
the discharge they were sending through the dam would decrease by almost 30 percent. Now the reservoir would rise even faster.

Meanwhile, a number of people noted something even more disturbing than leaking couplings or heaving concrete: the dam itself appeared to be shaking.
Many years later, people’s memories of this would conflict. Glen’s vibration monitors registered no unusual movement, but over the next several days, it was clear to everyone on site that
something
was being rattled. By now, they had been forced to resume sending a limited amount of water through the spillways, and the worsening cavitation—particularly in the east tunnel—was sending tremors through the sandstone.
Those vibrations were especially noticeable in the lunchroom, which was tucked next to the machine shop and the #8 generator on the east side of the dam. During their breaks, the crews could hear an ominous rumbling and crackling, punctuated by an occasional hollow boom. One worker, who had served in Vietnam, would later liken this to the sound of distant artillery. Another would recall having to hold on to his sandwich to keep it from moving around on the lunch table. By the second week of June, the vibrations were causing the roll-up doors on the machine shop to shake so violently that they had to be braced with two-by-fours.

It was around this time that Gamble began growing concerned about his manpower. His crews were working double shifts, and although the majority of them seemed to be holding up well, a handful were getting jittery. The worst of this group was a welder in the mechanics crew who had taken to walking out onto the transformer deck, staring at the spillway portals, then wandering back inside the power plant and asking his coworkers if the dam might collapse.

Fearing that such anxiety could be infectious, Gamble ordered Dhieux to start assigning the nervous welder to tasks that would keep him indoors. This kind of behavior, Gamble knew, was not merely unhelpful, but also displayed a fundamental misunderstanding of how well built Glen actually was.

On the other hand, however, such fears weren’t entirely irrational. Especially when one considers what takes place when a dam fails.

T
here is
something about a dam break that seems to awaken an almost atavistic terror in the human mind—perhaps, in part, because the litany of such disasters extends so far back in the history of civilization.

Although no one knows who built the first dam,
the oldest structure for which evidence remains is Sadd el-Kafara, a seventy-eight-foot-wide structure filled with sixty thousand tons of gravel that the ancient Egyptians raised on the Nile about twenty miles south of Cairo around 2600 BC, about the time they were building the first pyramids. Sometime after its construction (the records are sparse on this point), the dam was overtopped and destroyed during one of the Nile’s annual floods. Historians aren’t able to say much about what kind of havoc this caused—how many crops were wiped out, how many lives might have been lost. But after Sadd el-Kafara’s breaching, the Egyptians shied
away from building large dams for a
very
long time. They didn’t tackle another big engineering project on the Nile until they teamed up with the British to build the Aswan Low Dam, which was completed in 1902.

In the meantime, a host of other cultures experimented with dams in the hope of harnessing their benefits while mitigating their potentially catastrophic costs. Among the most successful were the Mesopotamians, who laid out a vast system of irrigation fed by numerous earthen dams on the Euphrates River during the reign of Hammurabi, who ascended to the throne of Babylon in 1792 BC. The maintenance of those dams was taken so seriously that Hammurabi’s famous set of 282 laws—the world’s first written code of public justice—flatly stated that if a flood occurred as a result of a dam break,
“then shall he in whose dam the break occurred be sold for money, and the money shall replace the corn which he has caused to be ruined.” As the author Bruce Barcott has pointed out, it was not the owner’s assets that would be sold to pay for the damage, but the owner
himself
—a powerful testament to the consequences of dam failure.

Centuries later, a more graphic illustration of this principle unfolded nearly two thousand miles to the south when the Great Dam of Marib, an enormous bulwark on Yemen’s Wadi Adhanah that was one of the engineering wonders of the ancient world, failed in either AD 570 or 575. The damage was so extensive—more than fifty thousand people were forced to abandon their homes and move away—that the dam collapse is actually mentioned in the Koran. Among other things, the failure of Marib underscores that, with the notable exception of warfare, nothing that premodern human beings created harbored more potential for destruction than a dam failure.