LAVA FALLS, Ariz. – Nobody expected trouble approaching camp
above Lava Falls, despite the heavy rain. Change in the Grand
Canyon is supposed to happen slowly over millions of years.
Bob Webb of the United States Geological Survey, wearing a
battered green Arizona Feeds cap, jumped off the first raft. He
tied up around a tamarisk shrub with three half-hitch knots.
After helping unload, he ambled through resinous creosote and
piercing barrel cactus toward the mouth of Prospect Canyon, one
of the Grand Canyon’s 529 side canyons, which opens into Lava
Falls.

The side canyons are steep enough to hurl thousands of tons
of debris – sandy mud, gravel, rocks, and boulders the size of
houses – at deadly speeds. Debris flows helped form the 161
rapids in the Grand Canyon. The Chinese refer to such flows as
dragons. A debris flow can recarve a side canyon, create a new
rapid or even plug the river in minutes.

At Lava Falls, rocks and lava from dormant volcanoes have
blocked the Colorado River before. Eventually, the river always
pushed through the debris. Every two years on average the
Colorado would flood, and up to 20 times the normal volume of
water (sometimes more than 200,000 cubic feet per second) would
tear through the Grand Canyon, purging the river corridor as
determinedly as a forest fire eating through overgrown woods.
But that was before the Glen Canyon Dam. Now the river is
weaker.

At the mouth of Prospect Canyon, Webb looked up at perched
boulders the size of snowplows. Loose rocks and mud had piled
up. Prospect Canyon hadn’t blown since 1963. The dragon was due
for a visit.

“This canyon is like a loaded gun,” Webb said.
The next day, it rained again. Three members of Webb’s team
climbed up Prospect Canyon through a fine mist. Peter Griffiths
needed sediment samples from the top. He’s trying to develop a
model for predicting debris flows with an eye to protecting
tourists camping along the river. John Elliott, a hydrologist
from USGS in Denver, studies debris flows throughout the West.
Surveying expert Steve Eudaley, also a mountaineer, came along
for the climb.

Boulders and ledges shone cold and slippery. It was so quiet
that the tap of a wedding ring echoed. The men groped for holds,
trudging through soaked talus, gaining about 1,000 feet. Finally
they reached jagged, lava-coated spines above a waterfall, the
blackened headwall where Prospect Canyon’s dragon sleeps.

A rock fell, like a bomb in the mist. Its cold slap
reverberated off sandstone cliffs.

Later in camp, rain fell harder. The wind picked up. Tents
were leaking, causing sleeping bags to lose some of their
warmth. As the scientists played cards at dusk, they talked
about warmth, conserving food supplies, whether roads above the
rim were washing out. Through static on the shortwave radio,
Webb heard forecasts predicting at least one more day of rain.
Around midnight, the wind knocked over tables and tarps,
scattering kitchen supplies except for a squat heavy blender.
Webb staggered out of his tent by the river, catching glimpses
of the wreckage in the beam of his headlamp. He shook his head
and went back inside.

An hour or so later, there was a faint trickling sound, as if
something was squeezing water out of the ground. The pitch of
the cascading water in Lava Falls rapids changed. Not higher or
lower. Different.

NO tree is safe in the Grand Canyon’s wild side canyons. No
campsite or fish pond survives forever.

In contrast, much of the Grand Canyon’s main river corridor,
away from the side canyons, seems tame as a Disneyland ride. Man
did the taming – damming the river to provide power and water –
which created cooler, regulated currents starved of silt.
Scientists are just now discovering the sweeping effects.
This presents a dilemma. We can let past, man-caused changes
take their course in the Grand Canyon. It still looks beautiful.

Or we can try to correct imbalances.

This winter, Webb and his scientists ran the river on a
mission to help confront this dilemma. They focused on the
invasion by alien species and effects of debris flows on the
weakened river south of the Glen Canyon Dam.

When the government built the Glen Canyon Dam 32 years ago,
federal officials knew itwould create a huge pond – Lake Powell
– that would inundate places a handful of visitors had compared
to cathedrals. But nobody expected an overhauled ecology or that
debris flows would overwhelm a weakened river down from the dam.

Like a child damming silt in the gutter after a storm, the
government has found that one intrusion on the natural system
leads to another.

“”Now debris flows from side canyons are getting the best of
the nation’s fifth biggest river,” says Webb.
The floor of the Grand Canyon may be rising, instead of
growing deeper as it did for more than five million years, he
says.

Webb’s team has traveled from side canyon to side canyon for
nearly a decade, documenting past debris flows, measuring how
much each one constricted the river. A river-running industry
that generates $20 million a year wants to know. The scientists
often joked during their arduous climbs about being caught in a
debris flow. “”It would be great, if you survived,” Griffiths
said. “”You could get data right away.”

The team also is scrutinizing new life appearing in the
canyon. Several native fish are gone – the Colorado squawfish,
roundtail chub, bonytail chub and razorback sucker – replaced by
brown trout and striped bass. The river otter is gone. Some
midges are disappearing, government ecologist Larry Stevens
says. Biting flies, poison ants (red harvester ants), cowbirds
and great-tailed grackles are increasing. Prolific plants such
as ravenna grass, camelthorn and tamarisk are crowding out
native plants such as willows. There are more plants in general
because there are no floods to wash them away.

Another team, led by Stevens, recently completed two 13-day
expeditions to remove ravenna grass by digging it up with
shovels. A few years ago, ravenna seeds blew into the canyon
after a National Park Service ranger planted some around the dam
visitor center. The seeds spread throughout the canyon, taking
hold aggressively in the shade of other plants, then growing
rapidly into reddish bunches of grass up to 12 feet high.
“”If you allow ravenna grass to take over, it will shape the
rest of the ecosystem,” Stevens says. He and his six-member
team dug out more than 4,500 clumps.

Webb’s team has matched more than 1,000 photos taken along
the river corridor before the dam with current photos. The
paired photos show very little change in vegetation between 1869
and 1963, when the Glen Canyon Dam plugged the river. After 1963
the results are dramatic.

Today’s lush canyon beckons like an oasis where, in the old
days, leafless trees jutted horizontally downriver as if frozen
in the middle of a hurricane. Back then, driftwood bent
Daliesque around boulders. Mud splotches dotted rocks in the
wake of fierce floods.

This winter’s trip, which has led to the Lava Falls rapids,
may be the last for a while. Political battles in Washington,
D.C., are beginning. The clock may be ticking for environmental
research. Intellectuals are reconsidering the virtues of the
artificial and the natural. This three-week expedition started
just below the dam at Lees Ferry and followed the river 240
miles. During those weeks, a team of diverse specialists began
to grasp how Americans are remaking one of the world’s biggest
natural wonders.

Feb. 21, 1995

NINE government scientists, led by Webb, leave Flagstaff at
dawn. They ride along the south rim of the Grand Canyon in a
white bus, full of questions and energy. The bus passes a
billboard advertising “”Everybody’s Authentic Trading Post.”
They head for two motorized rubber rafts at Lees Ferry.
They’ll load the rafts with nearly a ton of food, winter
equipment scrunched into water-tight bags, and
industrial-strength rain gear. The river banks sometimes are icy
in winter, too cold for a wet suit. Webb’s rule for preparing to
negotiate these canyons and white-water torrents: “”Pretend you
are playing in front of a freezing fire hose.”

Some odd stuff protrudes from a trailer towed by the bus:
five plastic pink flamingos, eight lawn chairs, a
battery-powered loudspeaker for Dick Dale’s surf guitar music
(“”Unknown Territory”), and a black skull-and-crossbones flag.
Everybody on the bus has a weakness for wildness. They talk
of impending floods on central Arizona’s Verde River. The more
the crew can learn about the Grand Canyon, they believe, the
better the odds of keeping it healthy.

They are psyched for three weeks of camping on the Colorado
River banks, awakening to the smell of cook Meg Viera’s coffee
at 6 a.m., running rapids, and climbing side canyons to collect
sediment samples, survey past debris flows, study plants, and
match photos from seemingly impossible locations that test
rock-climbing skills. Rain or shine, the data collection will
continue until boatman Kenton “”Factor” Grua blows his conch
shell at dusk.

Near the front of the bus, Webb hunches over a reconnaissance
photo from a 1952 trip. He thrives on the road. He lives almost
half his life away from his wife, an emergency delivery room
nurse, in Tucson. His eyesight is failing, so he leans close to
the photo, picking out details.

The photo shows a typical early canyon scene: murky water
coursing through a barren corridor. Boulders the size of
Cadillacs litter the banks. Sand has piled up against the rocks.
There aren’t many plants in 1952, because they can’t survive the
seasonal flooding and scorching summer droughts.

Webb focuses on two rocks sticking up from a sandy beach by
Badger Rapids. One rock is the size of a dinner plate, the other
is as big as a treasure chest. Then he points to a tiny tamarisk
shrub.

“”You’ll see our problem at this site,” he says. The site is
the first camp, about 8 miles downriver from Lees Ferry.
The bus stops near some Navajo hogans below Echo Cliffs. On
Sept. 8, 1994, a debris flow tore down from the cliffs, across
the road here, and careened down Jackass Creek into the river,
pinching Badger Rapids.

USGS researcher Mimi Murov and photographer Dominick
Oldershaw leave the bus here to follow the path of the debris
flow down to the river. Webb wants a photo looking down on the
site from the rim, replicating an earlier photo. He and the
others – Ted Melis and Elliott of USGS, Griffiths of the
University of Arizona, Eudaley, photographer Steve “”Special
Agent” Tharnstrom, park ranger Marker Marshall, Viera and
boatmen Grua and Bob Grusy – will pick them up at Badger Rapids.
They hike across Marble Plateau, until the canyon opens like
a giant geode. The beachshown in the photograph is there, though
the sand bars seem smaller than in the photo. There are many
more plants.

Up on the rim, there’s garbage. This is where car companies
take photos of vehicles for advertisements, where movie crews
film stuntmen hanging out over the canyon. There are oil cans,
beer cans and shards of a shattered mirror glittering in the dirt.
The scientists climb down Jackass Canyon. It dips and bends
like a melted stove pipe, almost vertical at points, plunging
down 1,000 feet to the green river. The debris flow last fall
smoothed the reddish sandstone.

A dead cow’s bones, picked clean by ravens, disintegrate in
the gully. The tilted head, looking up the creek, suggests the
cow died in the avalanche of rocks and mud.

Webb and crew already are surveying the site when Murov and
Oldershaw arrive at midafternoon. Webb is wearing a festive
necktie with his T-shirt.

“”This is the smallest I’ve ever seen these sand bars,” he
says, sounding slightly troubled.

Webb points out the two rocks he had pinpointed in the 1952
photo, rocks that appeared about the size of a dinner plate and
a treasure chest. Today, they are huge, the size of tugboats. It
is dramatic evidence of sand erosion; the uncovered rocks
remained while the Colorado’s hungry water, starved of silt, has
eaten away at the beaches.

Webb points out other changes. Rocks from the debris flow
have spilled into the rapids. Blood-red tamarisk stalks are
thickening everywhere. They crowd out willows on the wet river
banks, as roots suck up river water. A single tamarisk produces
10,000 seeds. A tamarisk seed falling on wet sand can sink roots within a
month. Native desert plants aren’t as prolific.
Elliott and Griffiths inspect rocks. Tharnstrom matches
photos of the rapids. Murov strolls past thickets of shrubs.
Eudaley and Melis use electronic surveying equipment to plot
contours of the sediment deposited by the debris flow.
Webb supervises, ambling around like a gunslinger with a look
of mild consternation.

“”I look at this river now, this river does not represent
wilderness,” he says. “”It is not a natural system anymore.”

Feb. 22

ABOUT 18 miles into the journey, the team stops at a side canyon
where, on July 24, 1987, limestone boulders hurtled 300 feet
from overhead cliffs, unearthing a layer of loose shale, which
all gained momentum and buried a popular beach. It was a
relatively minor debrisflow, yet it narrowed the Colorado River
by 10 meters. A 1984 photo shows a sandy beach with room for 25
tents. The debris flow hit on one of three nights that month
when the beach happened to be unoccupied by rafters.
“”Nobody’s been killed yet by one of these debris flows,”
Melis says as he gazes through the lens nicknamed “”Idi Amin” –
the EDM, or electronic distance measuring scope. “”The use is so
high in the summer that it’s just a matter of time.”

Feb. 23

SOME scientists speak scathingly of “”Disneyland Diversity.”
They hate the idea of “”virtual wilderness” (nature remade to
amuse people on vacation). Many want to preserve and protect
wilderness that remains, as opposed to managing a naturalistic
garden.

Who’s to say whether today’s altered Grand Canyon is better
than the way it was before?
Bald eagles and ducks hover overhead as the rafts enter a
verdant channel. We are going to Crash Canyon, a side canyon 62
miles down from Lees Ferry, named for the 1956 commercial
airliner crash that dropped dozens of dead bodies into the canyon.
In old photos this is flood-beaten land. But today in the
absence of floods, plants multiply. Talus sliding from side
canyons, backing up the river here and there, has created pools
of calm water. Marshes are forming around these pools.
The quacking ducks flap up and down the river banks. Wildlife
teems – heron, coyotes, deer, bighorn sheep, bobcats, ringtailed
cats. Trout and striped bass swim in sunlit green pools. Above,
two bald eagles perch on a cliff. Once threatened, eagles in the
Grand Canyon now thrive on non-native trout and bass.
A thousand feet below the canyon rim, a helicopter clacks;
inside are park service rangers counting eagles. Next year,
federal biologists plan to introduce some of the condors
raisedat a cost of $25 million in California.

Webb stops at Vasey’s Waterfall – spring-fed froth spraying
from a hole in a red limestone cliff. The water feeds two acres
of wetland populated by monkey flowers, watercress, maidenhair
fern, poison ivy, redbud and coyote willow. Biologists who
stopped here in 1991 found the Kanab
ambersnail. It’s a dull gray snail, stuck to a yellowish shell
no longer than three-fourths of an inch.
Webb sees no Kanab snails. Because the snail is endangered,
the government is supposed to make sure nothing happens that
could hurt it. Nobody really knows what could hurt it, except
that floods might wash it away, an argument Colorado officials
use in opposing simulated floods to revitalize the canyon.
“”The snail in the canyon is an ecological indicator of the
health of the canyon,” says Jim Lochhead, Gov. Romer’s director
of natural resources. “”It needs to be protected.”
Webb’s question is: Should we worry about a snail the size of
a pencil eraser when floods could help the whole canyon?
Even among government scientists, the Endangered Species Act
reeks of dizzy romanticism. Life in the canyon evolves, the
scientists say. Extinction is natural. Taking care of the canyon
shouldn’t mean prolonging a moment in evolution at the expense
of the canyon. The scientists call for a more flexible
Endangered Ecosystems Act. U.S. Fish and Wildlife Service
director Mollie Beattie has called for the same.

“”A lot of the problems come down to single species
management,” Webb says. “”You focus on a single tree and forget
about the forest. But the species act does more good than
damage, because the rate of extinction is so high. We need to
have something in place.”

Throughout the canyon, dozens of park service rangers endure
an often thankless job enforcing intricate rules to keep the
canyon idyllic. They hack out thorny thickets on eroding
beaches, and plant trees along worn trails.
In summer, the canyon gets heavy use. The park service is
planning parking lots and wilderness trails to accommodate an
additional 2 million tourists a year on the canyon rim. Park
rangers police 22,000 people who run the river on rafts every
year, trying to keep them from loving it to death. Most of the
rules make sense: River runners must haul out all waste,
including human excrement. No golfing is allowed, since falling
rocks are enough of a hazard for most campers. Sometimes the
rangers get carried away, like the time one reportedly ticketed
a commercial cook for baking a cake in a Dutch oven, citing her
for “”scorched sand.”

Park managers try to restrain airplane and helicopter pilots
hauling tourists over the canyon, requiring them to fly above
the rim. It’s harder to control the air pollution pouring into
the canyon from Los Angeles and Las Vegas (visibility has been
reduced to half what it was in the 1950s), and sewage washing in
from Page.

“”In the summer, this place feels like a country club,” says
Viera, a soft-haired woman with a kind face who orchestrates
several commercial trips a year.

“”The idea of wilderness is pretty much lost,” she says,
referring to summer crowds along the river. She confesses that
the difference between the real canyon and the altered version
sometimes seems confusing. The canyon still looks beautiful. If
you’re not happy here, something’s wrong, she figures. Sometimes
she questions whether scientific knowledge actually will help to
preserve the Grand Canyon. “”It’s been studied to death,” she
says.

Feb. 26

WEBB wants to pick up the pace. He feels an urgent need to
document as many changes as possible in the vegetation and
contours here, a mile below the south rim’s Comanche Point, at
the base of the Tanner side canyon.

But today Webb is sick with a virus. He can’t keep food down,
has to get out of the sun. He abandons a pile of rocks he’s been
studying and closes his notebook. He scuffs at a clump of bromus
tectorum, commonly known as cheat grass, associated with
overgrazing, that has found its way into the canyon.

“”It’s another invasive plant that is taking over the world,
and there’s not much we can do about it, because we don’t
understand it. It gets really dense, and it crowds out
everything else.”

Webb heads for camp, pausing at a gnarled black mesquite
tree. The mesquite tree had grown up amid floods; it’s been
marooned here, high and dry, by the regulated river that favors
the cheat grass.

Meanwhile, Webb’s crew fans out across the snout of a debris
flow that crashed down on Aug. 22, 1993, after an intense
thunderstorm. The 7,500 cubic meters of debris constricted the
river by about a third, increasing the severity of Tanner
rapids, creating pools upriver that nourish new marshes.
Melis works the Idi Amin. He’s a meticulous scientist. His
tent is dirt-free and he carefully transfers surveying data onto
a laptop computer every evening.

As Melis gazes through the scope, he sums up his thoughts.
“”The river used to rule,” he says. “”Now the side canyon
tributaries have the upper hand. They probably will … as long
as the dam is there.”

He looks through the scope as he speaks, and the scope shoots
a laser beam at three-way prisms mounted on poles held by Murov
and Eudaley. “”Rivers are meant to move sediment from high
points to the oceans. That’s what this river used to do for a
living: move sediment. That’s been disrupted. I lament that.”
As he speaks, a hiker approaches, wearing a purple shirt,
black shorts and white Stan Smith sneakers. It is Tom Deeds, 47,
a potato farmer from Colorado’s San Luis Valley. Deeds last
visited this part of the Grand Canyon as a college student. He’s
been hiking the backcountry for 10 days.
“Walking along here, it feels like this river needs to be
flushed,” Deeds says.

“”There is no authentic nature anymore,” he says, meaning
nature not touched by human activity. He says he’s not bothered
by the change in water color as much as pollution.
Back in camp, Webb lies in front of his tent with a fever of
101.8, while Tharnstrom and Oldershaw sift through old photos
they still need to match.

“”Everybody loves a zoo,” Webb says. “”Is that really what
we want from our national park system? If any place should be
unspoiled, shouldn’t be a zoo, the Grand Canyon is it.”

Feb. 27

ABOUT 4 miles downriver from Tanner Canyon sits a silvery green
and gold marsh fed by Cardenas Creek. This is where biologists
have spotted endangered southwestern willow flycatcher birds.
It’s early in the year to see one; flycatchers winter in Central
America. But this marsh is probably the only place in the West
where you could see one. The flycatchers live here in willows,
also innon-native tamarisks. Male flycatchers cruise the marsh
grasses nipping flies that they carry back to females in nests
shaped like oversized coffee mugs.

The marsh is closed during parts of the summer. Hidden park
service cameras monitor the place. A simulated flood, carrying
hungry water from Lake Powell to flush the Grand Canyon, might
wipe out flycatcher homes.

“”It’s actually a pretty nondescript little bird,” Factor
says. Murov tries to imitate their trill: “”Fitz-bew!”
The marsh isn’t natural, and the river naturally wants to
erode the area, Webb says. “”This bird’s habitat is artificial.
It all seems real sketchy to me.”

March 1

AN icy rainstorm pelts the raft as we slide out of Bedrock
Rapid, past swelling pools, and drift toward Tapeats Beach for a
photo match. Tharnstrom decides to shoot it despite the rain. We
tie up, and clamber along river banks covered with slippery
rocks, tamarisks and green clumps of grass.

The 1952 photo shows a sunny, sandy beach scene. Women are
seated. A wooden dorrie marked Mexican Hat is tied up where we
stand today. The beach then was known as a party paradise where
people enjoyed driftwood bonfires and fished.

A lean man in the foreground of the photo, Bobb Rigg, walks
happily through the sand. He is a pilot who set the river speed
record in 1951, guiding a dorrie 276.5 miles from Lees Ferry to
Lake Mead in 38 hours. (The record held until 1983 when Factor
and two friends made the trip in just under 37 hours without
stopping at night.)

Today Rigg, 64, hardly recognizes Tapeats Beach.

“”Before you had the sand, and driftwood,” Rigg said in an
interview from his home in Anchorage, Alaska. He works as an FAA
flight surgeon and an eye doctor.

“”You could sit in the water. You spent a lot of time in the
water because it was refreshing, and warm. We’d been exposed to
the river since we were kids. We’d lived by the Colorado River
up in Grand Junction. It was an escape for people who had been
in the war, including my brother. There was this awesome silence
in the canyon.”

Rigg votes Republican. He doesn’t consider himself an
environmentalist. But he says the government is making huge,
greedy mistakes that degrade the Grand Canyon.

“”What’s more important, higher energy prices or maintaining
nature’s balance? You’re talking about the normal God-created
course of the Grand Canyon. Who cares what some bureaucrats
think?”

Like Rigg, many of the men who pioneered the river-running
industry before the dam say they are deeply saddened by man’s
unexpected changes. Before 1946, only about 100 people had run
the Colorado River. Last fall, Webb invited survivors for a trip
designed to evoke memories and record them, a test for
scientific conclusions.

One boatman, 92-year-old Frank Wright, refused to go. Wright
ran the river starting in 1948. His last trip was in 1957.
“”I have certain personal feelings about the river,” Wright
says from his home in Blanding, Utah. “”Have you had an
experience where you don’t want to see some things again?”
But other men and women did go. A report on their
observations shows widespread agreement with observations by the
scientists: overhauled ecology and debris from side canyons
overwhelming the once-mighty river.

One was 73-year-old Les “”Buckethead” Jones. In 1962, Jones
ran the river in a 19-inch-wide, 16-foot-long metal kayak. He
paddled with a camera mounted on his helmet – a World War I
helmet shell. He compiled detailed backcountry maps and many of
the photos that Webb’s crew is matching on this trip.

“”I want to remember the river like it used to be,” Jones
says. “”Man’s architecture is never as good as nature’s.”
Scientists should still try to revitalize the canyon with
artificial floods, Jones says, questioning Colorado leaders’
refusal to let any water flow freely downriver.
As for new wildlife, eagles and condors may look beautiful,
he says, “”but any time you introduce something new, something
else in the canyon pays the price, usually the former
inhabitants.”

The old timers follow today’s debate among government
agencies. Each agency has an interest beyond the health of the
canyon. Fish and Wildlife wants steady flows that nurture
endangered species, but not big floods. The Park Service wants
steady flows that don’t change too fast, to protect rafters and
fishermen. The power producers want fluctuating flows tied to
urban demand for electricity, which generates money. The Bureau
of Reclamation is torn between building more dams and fixing dam
damage.

No agency puts the canyon first, the old timers say. They
feel the only way to do that is get rid of the dam.
“It was a big mistake,” says 92-year-old Wright.
Nobody plans to take down the dam before it wears out in 300
or more years. Anyway, there are 10 major federal dams
controlling the Colorado River, creating a succession of
reservoirs from Colorado’s Blue Mesa to Nevada’s Lake Mead. Even
without the Glen Canyon Dam, the river wouldn’t be wild and
still might not reach the Sea of Cortez.

At about 1:30 a.m. on March 6, muddy rainwater at the head of
Prospect Canyon unleashed boulders up to 7 feet wide. The
boulders hurtled downward like meteors at the river. They mixed
into a dark brown slurry. It sounded like a waterfall punctuated
with thuds. The slurry coarsed down in three furious pulses,
throwing up spiked torrents, churning and ripping out rocks and
mud and gravel.

After 32 years, Prospect Canyon was crashing while Webb’s
team slept at its base.
t the snout, rocks smacked like billiard balls, spilling
into the river. The big boulders settled. The slurry gained
momentum. It sprayed out a newly gouged gap atop the canyon with
the force of thousands of fire hoses.

From the top, this slurry fell 330 feet, pulverizing a cliff
where it hit, shooting out perpendicular from the cliff. Then
the muddy froth dropped 550 feet to the base of the waterfall,
where it drilled a hole 40 feet deep. The debris flow ultimately
moved an estimated 57,000 tons of mud and rocks. It cascaded
into the river for 18 hours. The dragon was cutting a new path.
A muddy mist hung in the air, almost too thick to breathe.
The scientists, in tents a quarter-mile away, didn’t hear it
at first.

At dawn, they went wild. Tourists might have been horrified.
But here, somebody was shouting “”Merry Christmas!” The
scientists rushed, tentatively at first, to glimpse the dragon’s
work.

“”We would have been toast,” Elliott said, staring at the
snout and up the canyon where he’d climbed the day before. Rocks
still were pouring into the Colorado River. They overpowered it.
This debris flow constricted the Colorado River by a third,
pinching off Lava Falls, one of America’s most treacherous rapids.
Getting through Lava Falls was always risky. Now the ledge
was sharper, and new whirlpools appeared around the black rock.
The slot at the top, which boatman Factor always aimed for, had
disappeared. The V waves were bigger, snapping like jaws where
rafts used to pass. It was likely dirt roads above the canyon
rim were washed out. There would be no way out for days. But
here at the bottom during the debris flow, Factor just focused
on the new Lava Falls. He envisioned his historic first run.

Meanwhile, Webb and Melis spread their arms to the sky and
danced. They whooped. In the middle of the destruction, they
reveled like children.