A Voyage Along Trump’s Wall

Canoeing the Rio Grande reveals how life and a landscape would be changed along the border.
The Rio Grande runs along Big Bend National Park, separating Mexico, on the right, from the United States, on the left. A border wall would be devastating to life on both sides of an already threatened river.

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When Dan Reicher was eight, he became fixated on wolverines. He admired their ferocity but, because they were endangered, feared for their survival. While poring over a catalogue of outdoor gear, he came across a parka trimmed in wolverine fur. He was outraged. His mother, a schoolteacher, and his father, an ob-gyn, urged him to put his umbrage to good purpose, so he sent the gear company a letter. After some time, he received a reply: the company was discontinuing the parka. Had his protest made the difference? Probably not, but, still, he inferred that a citizen, even a little one, had the power to effect change. “Boy, was I misled,” he said recently.

Reicher, now sixty-one, is a professor at Stanford and the executive director of its Steyer-Taylor Center for Energy Policy and Finance. Previously, he led Google’s climate and energy initiatives and served in the Clinton Administration as an Assistant Secretary of Energy. He has spent most of his adult life trying to help humankind move past its reliance on fossil fuels. Under President Trump, conservationists have seen decades of gains rolled back in a matter of months. Still, Reicher, like so many environmentalists, goes grimly about his business.

Reicher’s real obsession is water. He grew up in Syracuse, paddling on polluted lakes, and liked to collect and test water samples. When he was eleven, his parents sent him to Ontario on a canoe trip with a drill sergeant who failed to bring an adequate supply of food. Reicher, getting by on wild blueberries and toothpaste, had never been and would never again be as hungry, but, even so, he loved the whole thing. For a couple of summers in his teens, he attended the Colorado Rocky Mountain School, in Carbondale, where a French champion of the newfangled sport of white-water kayaking taught aspiring river-runners the eddy turn and the high brace. Reicher got to spend a week on the Green River, paddling through the vast Dinosaur National Monument. He was captivated by the journals of a predecessor there: John Wesley Powell, the Union Army major who lost an arm at Shiloh and later led the first expedition to navigate the length of the Grand Canyon. As an undergraduate at Dartmouth, Reicher joined the kayaking team and the Ledyard Canoe Club, which is named for John Ledyard, the eighteenth-century American explorer, who dropped out of Dartmouth after a year and paddled down the Connecticut River, from Hanover to the Long Island Sound, in a dugout canoe fashioned from a tree he cut down on campus.

In the spirit of these forebears, in 1977 Reicher and some fellow-Ledyardians embarked on an expedition of their own. A classmate, Tony Anella, from Albuquerque, was preoccupied with his home-town river, the Rio Grande, and had determined that no one in documented history had navigated the river’s nearly two thousand miles, from source to sea. He planned to be the first. The students secured backing from the National Geographic Society, which, a dozen years before, had sponsored a Ledyard trip along the Danube. For course credit, Anella, a history major, would compile a history of water rights on the river, while the other principal, Rob Portman, an anthropology major (and now the junior United States senator from Ohio), would take on the subject of mass migration. Reicher, a biology major, would assess the water and whatever life could survive in it.

Generally, the storied river descents, like so many iconic American journeys, have tended to be those which run west, down from the Continental Divide to the sea. And, of those, the torrent that drains the far slope of the southern Rockies, the Colorado, seemed to draw the love and the lore—it had deeper cataracts, bigger flows, gnarlier rapids, bolder boatmen, and fiercer fights over dams and acre-feet.

Four years ago, a reporter named Colin McDonald set out to document the river's depletion. “The Rio Grande isn't seen, treated, or valued as a river,” he said. “People think, The river is dirty, it's poverty, it's disease.”Photograph by George Steinmetz for The New Yorker

The Rio Grande had neither a John Wesley Powell nor a Lake Powell. It is typically considered, by those of us who don’t depend on it, little more than a boundary separating Mexico from Texas, a squiggly moat on a map. It represents a gateway to opportunity or escape for the migrants and fugitives, in life and in song, who cross it in the hope of a fresh beginning—a kind of baptism by border. Known south of the border as Río Bravo del Norte, and to the indigenous Pueblo people as P’Osoge, its various sections were given an array of now mostly forgotten names by sixteenth-century explorers—Río Caudaloso, Río de la Concepción, Río de las Palmas, Río de Nuestra Señora, Río Guadalquivir, Río Turbio, River of May, Tiguex River. The Rio Grande drops out of the San Juan Mountains, in southern Colorado, bisects New Mexico, north to south, and then, splitting El Paso and Ciudad Juárez, tacks southeast. The majority of its length, from El Paso to the Gulf of Mexico, with the S-turn of the Big Bend, forms the southern boundary of Texas, and of the United States. The river empties into the Gulf just past Brownsville, Texas. No part of the river is like any other. Typically, it is treated more as a managed scheme of discrete local parts—Taos Box, Elephant Butte Reservoir, Big Bend, Lower Canyons, Valle—than as an essential artery feeding a vast corner of our continent and a watershed connecting interdependent ecosystems, cultures, and nations.

Reicher, with Portman and Anella and another classmate, a photographer named Pete Lewitt, hiked down from the source, at Stony Pass, just east of Silverton, Colorado, and put in twenty-five miles later, below the first dam, in fibreglass kayaks, brittle precursors of today’s polyethylene creek boats. Two weeks later, they encountered their first great challenge, in the tricky rapids near Taos. The surge of snowmelt was greatly reduced by dams upstream. (And by drought: 1977 was the worst year, in terms of snowpack, in the past half century. The second worst? 2018.) The river was, in kayak-speak, bony. By the time they reached the confluence with the Santa Fe, below Cochiti Dam, there wasn’t much water left. Even forty years ago, the flow south of Albuquerque was so depleted by farmers and by the city’s sprawling population that the kayakers had to divert to the network of irrigation ditches that run alongside the river. At one point, a farmer in an El Camino pulled up next to them, unloaded two water skis, strung a rope from the trailer hitch, and towed Reicher along the canal. “First time I ever water-skied with dust in my face,” Reicher said.

Farther downriver, in the muddy flats at the head of the Elephant Butte Reservoir, in southern New Mexico, the water would neither support their weight nor allow them to paddle, so they devised a method of pushing their boats with their hands and feet while lying on the stern. Crossing into Texas, where the river meets the Mexican frontier, the Ledyardians switched to bicycles and rode along paved roads until, a couple of hundred miles later, the Río Conchos, running out of the Mexican state of Chihuahua, replenished the ancient riverbed, so that they could saddle up their kayaks again. Because of upstream depletions, the Rio Grande is really two rivers: one that fizzles in southern New Mexico (the locals there refer to it as the Rio Sand) and one that begins in West Texas. In between is the puddled and trenched borderland east of El Paso and Juárez—the Forgotten Reach, which, prior to the big dams, had been regularly revived (and scoured) by seasonal floods from New Mexico. There had even been eels in Albuquerque—fifteen hundred miles upstream of the Gulf of Mexico.

The Dartmouth expedition, now five strong, made it through the deep canyons and riffles of the Big Bend and then entered the Lower Canyons, the river’s most remote leg, which Congress, a year later, designated part of the National Wild and Scenic Rivers System. The desert eventually gave way to a subtropical luxuriance of palms, broccoli farms, and citrus orchards, the riverbanks and wetlands teeming with wildlife. The birds and animals didn’t recognize the border. The people, though, were defined by it. The kayakers regularly encountered Mexicans crossing the river with burlap bundles. Near Eagle Pass, they came across a bloated male corpse, with a noose around the neck. (“We tried to report him, but neither side was terribly interested,” Reicher recalls.) At night, burrowing into the invasive wild cane to make camp, they set off seismic sensors installed by the U.S. Border Patrol.

After four months on the river, they reached the Gulf. They posed on the beach, five gringos, tan and lean, brandishing the Ledyard flag. Relations among some of them had frayed, amid a clash of egos—endemic to such expeditions. Reicher and Anella have hardly spoken since. But the trip remains a highlight of their lives. To Anella, it was a religious experience. “One-half of the hydrologic cycle—it reached something deep in my soul,” he says. He likes to cite Ecclesiastes: “All streams flow into the sea, yet the sea is never full. To the place the streams come from, there they return again.”

Reicher prefers Heraclitus: “No man steps in the same river twice, for it is not the same river and he is not the same man.” Since 1977, he has been back to the Rio Grande six times; the river may have changed more than he has. Four years ago, a young newspaper reporter in San Antonio named Colin McDonald set out to duplicate the source-to-sea trip, using Reicher’s journals as a blueprint. He dubbed it the Disappearing Rio Grande Expedition. He soon discovered that the river was in even worse condition than it had been forty years earlier. Groundwater depletion, suburban sprawl, periodic droughts (attributable, probably, to climate change): every year, people were asking more of less water. He wound up having to walk a third of the river’s length. Reicher, who had helped McDonald raise money and get attention for the trip, joined him for a couple of actual-water segments—in the Big Bend and then the last miles, where the river limps into the Gulf. When McDonald did a slide show in Albuquerque, Anella approached him afterward and said simply, “That was my trip.”

After Donald Trump was elected, he pursued his campaign promise to build a wall along the nearly two thousand miles of border between the United States and Mexico. The Rio Grande’s “disappearance” took on fresh meaning. As imagined, such an undertaking would be devastating to life along an already threatened river.

Having been determined by the 1848 peace treaty that ended the Mexican-American War, the border traces the river’s deepest channel—the thalweg—which, because the riverbed frequently shifts according to the water’s whims, is in some respects notional. Of course, no one is proposing that a wall be built in the middle of the river, or for that matter on Mexican soil, even if Mexico is going to pay for it. So the wall would go on the American side, some distance from its banks—miles into U.S. territory, at times. It would cut people off from their own property and wildlife from the main (and sometimes the only) water source in a vast upland desert. The Center for Biological Diversity has determined that ninety-three listed or proposed endangered species would be adversely affected. The wall could disrupt the flow of what meagre water there is, upon which an ecosystem precariously depends. And it would essentially seal the United States off from the river and cede it to Mexico: lopping off our nose to spite their face. It would shrink the size of Texas.

The wall would cut people off from their own property, cede the river to Mexico, and shrink the size of Texas.Photograph by George Steinmetz for The New Yorker

There is also the matter of efficacy. The wall would probably delay a hypothetical crossing by a few minutes, depending on its design and the manner of the breach. There are videos of Mexicans deploying ladders, ramps, ropes, welding torches, and tunnels to get over, through, or under border fences. (There are about seven hundred miles of fence already, most of it in California and Arizona.) For a great deal of its length, the river is insulated on both sides by hundreds of miles of desert—inhospitable terrain that does more to discourage smugglers and migrants than a wall ever could. (The vast majority of hard drugs intercepted on the southern border is coming through so-called points of entry—the more than forty official crossings—hidden in vehicles and cargo.) And, while the banks of the river, for much of it, are free of impediments, except for thick stands of invasive cane and salt cedar, which can make life miserable for the Border Patrol, about a hundred miles of it cut through deep canyons far more imposing and prohibitive to a traveller on foot than a slab of concrete or steel. The canyons don’t require funding from Congress.

This winter, Reicher put together a trip on the Rio Grande, with American Rivers, an advocacy group, of which he’s a board member, to celebrate the fiftieth anniversary of the Wild and Scenic Rivers Act, and to begin to articulate, in an informal but pertinent setting, a response to Trump’s wall. (Last week, American Rivers, for the first time since 2003, included the Rio Grande in its annual list of the ten most endangered rivers.) This wasn’t so much an expedition as a floating Chautauqua, with a missionary bent. He and Bob Irvin, the president of American Rivers, invited me along. Among the guests were two grandees with dynastic connections to environmental conservation: Senator Tom Udall, Democrat of New Mexico, whose father, Stewart Udall, spearheaded the protection of vast tracts of American wilderness and was a crucial proponent of the Wild and Scenic Rivers Act; and Theodore Roosevelt IV, whose great-grandfather, the twenty-sixth President, used his bully pulpit, and hundreds of executive orders, to turn the federal government into a force for, and an enforcer of, land and wildlife conservation. Before American Rivers got involved, Reicher had invited Rob Portman, who has the kayak from the 1977 expedition mounted in his office on Capitol Hill, but his schedule was too tight, and he’d been back to the river a year earlier, with his family. “Last thing a Republican needs now is to be seen spending a week on a river with a bunch of tree huggers,” Irvin told me with a chuckle.

I’d never given any thought to the Rio Grande, despite its being the fourth-longest river in the United States. My first river trip was a five-night commercial float, on rafts, on the Middle Fork of the Salmon, in Idaho’s River of No Return Wilderness. It was 1985. I was a teen-ager, with my family and about twenty strangers—a group of gay men from Houston and New Orleans, and a biker hippie from Portola, California. The biker, who was a friend of one of the guides, went by Feets (he had got himself listed in the white pages as Amazing Feets) and spent his Middle Fork days aboard the supply boat, in jean cutoffs and a white tank top, rolling and smoking joints. I remember sitting on a sandbank one evening, after a consultation with Feets, watching the river flow—the molecules jostling past, toward the Main Salmon, the Snake, the Columbia, and the Pacific, and then up into the atmosphere and the jet stream and eventually, via cumulonimbus, back to the mountains upstream—and appreciating, really for the first time, the fact that this conveyor belt of snowmelt and runoff never stopped rolling, a quintessence of incessance unlike anything I could conceive of, except maybe time itself. Or an escalator. Then I wandered off in quest of some leftover Dutch-oven apple crisp.

Even in the clear-eyed light of day, the Middle Fork worked its magic. There was something addictive about the unfurling, around every bend, of new vistas. The fellowship, too: by the end of the trip, all of us, clients and guides, vowed to visit one another soon, making what I now know are routine pixie-dust promises that in this case were so unlikely to be kept that it took only a few days for the spell to wear off. (A river trip is a little like summer camp that way.) I passed through Portola a year later and found “Feets, Amazing” in the local phone book. No answer.

“Thank God she was wearing a helmet.”

Soon afterward, I learned how to do an Eskimo roll, and spent a decade white-water kayaking wherever and whenever I could. Lehigh, Lochsa, Youghiogheny, Ocoee, Gallatin, Tohickon, Penobscot, Payette: the names of the rivers summon up boulder gardens, azure pools, high-speed surf waves, life-threatening keeper holes—and those mesmerizing cellophane stretches where the water, clear and unriffled, accelerates over a rocky bed, getting ever shallower, before dropping into the aerated tumult of a rapid. To safely navigate big rapids, and to play in them with some assurance, you have to acquaint yourself with a fundamental principle: water seeks its own level. This is why it flows toward the sea, why it churns back on itself when it drops steeply, and why, if you lean the wrong way crossing an eddy line, it flips your boat—and why, if you fail to roll up and have to swim, it fills your boat (and your sinuses) as it dashes you against the rocks. Whatever level the water is seeking, you are better off with your head above it.

Work, city life, injuries, and children put an end to my boating. But, like Ishmael, I intermittently get a strong urge to take to the ship. Several years ago, I joined a private—unguided—raft trip on the Colorado River, through the Grand Canyon, put together by a few friends, some of whom had guided on the river in their twenties. Most of us were strangers to one another, but the pixie dust was strong. Two weeks in the canyon, with no connection to the outside world. The rim the edge of your universe, the river your only way through it. Among the promises I made to myself, down on the Colorado—promises that were inevitably broken—was that I would spend a greater portion of my life, or what remained of it, on swift, wild, and scenic American rivers.

So I signed on to Reicher’s trip. At his urging, I started reading “Great River,” Paul Horgan’s muy grande Pulitzer-winning account of the Rio Grande, which, like “2001: A Space Odyssey,” reaches about as far back as a history can. It begins:

Space.
Abstract movement.
The elements at large.
Over warm seas the air is heavy with moisture.

The guy was speaking my language.

This is why, after a five-hour evening drive from El Paso through the shimmering blood-meridian expanse of West Texas, then a morning of sorting gear, meeting and greeting, and bouncing in a shuttle van through the ocotillo-and-yucca high desert of Big Bend National Park, I found my heart droop upon catching sight of a sag of umber water, its banks choked with cane. Great river? It looked more like a polluted tidal lagoon in Flushing, Queens. The put-in was at the foot of a boat ramp of bulldozed mud. An empty beer bottle, properly hurled, would have made it over to the Mexican side.

At the edge of this slough sat a flotilla of twelve canoes, one kayak, and a supply raft. The lead guide, John LeRoy, a ropy, leathery dude with a gray beard and ponytail, was busy rigging the boats. Eventually, he gathered everyone for an orientation speech—safety, paddling and rigging technique, chain of command. He brought up the urination routine (“Pee in the river, whenever possible. Dilution is the solution to pollution”), but said he’d address the poop question later. Something about LeRoy’s edgy forbearance seemed to say New York City, and, sure enough, he was from Elmhurst—né Jean-Yves, the son of French immigrants. His father had been a waiter in the theatre district. LeRoy had worked blue-collar jobs all over the country, including making tubular sleeves for die-casting foundries at a factory in Milwaukee. In 1996, he quit, moved to Terlingua, Texas, and, having never before worked on a river, set out to become a guide. He’d met his wife, also a river guide, on the Middle Fork of the Salmon. “This is blue-collar work, too, but it’s awesome,” he said. “Everywhere you go, there’s water.”

We were a few miles upriver of Boquillas Canyon, where the river cuts through the limestone fortress of the Dead Horse Mountains, by the Sierra del Carmen. That’s the stretch we were heading for—four days, three nights, just thirty-three miles, in one of the most protected sections of the Rio Grande. The water flow was low, the workload light, the dangers few, the rapids negligible. This was a commercial guided float trip, cosseted and catered. Still, we’d be out of touch and off the grid. Four days without cellular coverage can lead to palpitations and debilitating night sweats. So can scorpions and rattlesnakes.

For centuries, Boquillas Canyon was considered impregnable, by boat anyway. There is no record of anyone ever having navigated it when this territory belonged to Spain. In the nineteenth century, numerous survey parties, daunted by the prospect of big rapids and no escape, didn’t venture past the entrance. Three Confederate deserters claimed to have floated from El Paso to Brownsville, in 1861, in a pair of lashed-together dugout canoes but left no description of the Big Bend canyons, which would have represented a noteworthy test. In 1899, a boating expedition led by Robert Hill, an officer for the U.S. Geological Survey, set out to explore the canyons. “Every bush and stone was closely scanned for men in ambush,” he wrote afterward. The country apparently teemed with bandits, the most fearsome of them a Mexican named Alvarado, who was known as Old White Lip, because his mustache was half white and half black. The Mexicans on Hill’s expedition were supposed to kill Alvarado if they encountered him, but, at some point, they floated right past him, without realizing who it was, as he watched from the bank with a baby in his arms. Maybe he’d shaved off the mustache. Hill and his men found the going in Boquillas less arduous than expected, and filled in a new section of the map.

One of our guides was named Alvarado—Austin Alvarado. No relation: his parents were from Guatemala. Alvarado had recently returned from a trip led by a twenty-nine-year-old filmmaker named Ben Masters; they’d paddled, and ridden horses and mountain bikes, along the Texas border, from El Paso to the Gulf, for a documentary Masters was making, called “The River and the Wall.” Masters, a wry, red-headed horseman with a telegenic Texas drawl, was on this trip, too, along with the film’s producer and another cameraman. This time, strictly speaking, Alvarado was a guide and Masters a client. Another client was Colin McDonald, the one who’d done the source-to-sea trip in 2014, and who was now working on endangered-species policy for the Texas state comptroller’s office, having capitulated to the looming extinction of his own species, Reporterus localus.

All told, there were twenty guests and four guides. Reicher, who had his daughter and his son along (one a recent graduate of Dartmouth, the other headed there next fall), made introductions. As people paired up, Udall, unaccompanied by staff or spouse, chose me as his stern man. He is sixty-nine years old, of medium build, and had on a long-billed sunhat, sunglasses, thick sunblock, a long-sleeved fishing shirt tucked into khaki-colored quick-dry pants, and Teva sandals: no Amazing Feets, my bow man. He had a Jimmy Stewart aw-shucks air about him and a way of working my first name into every other sentence, but he wasn’t above having a beer on the water or sharing cold-eyed appraisals of his colleagues on Capitol Hill. He is a liberal-voting Democrat with a lifetime score of ninety-six per cent from the League of Conservation Voters, but has some sensitivity to the needs of constituents trying to make a living off the land in the arid West. He’d spent a lot of time outdoors through the years. He’d been an instructor for Outward Bound, in college, and every summer he spends a week or two backpacking in the wilderness of the Wind River Range, in Wyoming. (His cousin—and longtime travelling companion in the Winds—Randy Udall died there five years ago, on a solo hike.)

Udall began to tell the story, over his shoulder, of his family and its roots in the Church of Latter-day Saints. One great-grandfather, David King Udall, was a Mormon bishop and a polygamist, who went to prison for perjury. (He’d lied when Mitt Romney’s great-grandfather was being investigated for polygamy; his bail was posted by Barry Goldwater’s father.) A great-great-grandfather, John Lee, who had nineteen wives, was one of the leaders of the Mountain Meadows Massacre, in 1857, in which a Mormon militia murdered a party of settlers in southwest Utah; Lee was the only one executed for the crime.

“The idea of a wall is so un-American to me,” a river guide said. “Is this America first, or America only?”Photograph by George Steinmetz for The New Yorker

The family eventually made its way toward the political mainstream, as the West fell under the sway of Washington. Mo Udall, Tom’s uncle, was a liberal congressman who ran for President, in 1976. Mo’s son, Mark, spent six years in the Senate. Tom’s father, Stewart Udall, was Secretary of the Interior under Presidents Kennedy and Johnson. “L.B.J. bullied my dad,” Udall said. “He considered him a Kennedy guy.” (Stewart had supported Kennedy over Johnson in 1960.) “But my dad had a great relationship with Lady Bird.” As a Mormon with deep roots in the Southwest and a dam-happy constituency at home in Arizona, Stewart Udall was constitutionally and politically inclined to develop natural resources, rather than preserve them. “I was born with a shovel in my hand,” he liked to say. But his adventures outdoors and his friendship with Rachel Carson and other environmentalists made him increasingly receptive to opposing arguments, and he wound up presiding over the federal government’s most prolific spree of land and species protection, including the Wilderness Act, the Endangered Species Preservation Act, and the Wild and Scenic Rivers Act.

The Senator and I were getting the hang of our boat. It was an Old Town canoe, almost seventeen feet long and piled high with gear. We were approaching the old mining village of Boquillas del Carmen, on the Mexican side. Udall called out “Hola! ” to some men squatting on the bank with a skiff that they employed to ferry people back and forth across the river, at five dollars a head. The Boquillas Crossing, at a shallow and slack stretch of the river, has long been a port of entry. The Border Patrol shut it down in 2002, after the attacks of September 11th. This devastated the village, which, on the Mexican side, is about four hours away from the nearest paved road. In the absence of tourism, some hundred remaining residents scraped by for a decade. In 2013, the U.S. opened the crossing again, allowing Big Bend visitors to go over to Boquillas for the day or the night, and Mexicans to go to the other side to sell souvenirs—or to retrieve grazing cattle that might have strayed there.

A little farther downstream, a stretch of fast water steered the boats toward a cut bank and some strainers (as midstream downed limbs and trees are called), and LeRoy pulled up on a gravel bar—Mexico—to supervise, while a vaquero in reflector shades and a backward ball cap sat sentry on a burro. “Buenas tardes,” the Senator said.

“Everyone has a river story,” Udall told me. His had to do with a Grand Canyon trip he took with his father, when he was a teen-ager, in June, 1967. As a congressman from Arizona, and then as Interior Secretary, Stewart Udall had for many years supported two controversial projects in the Grand Canyon: proposed dams in Marble and Bridge Canyons, which would have turned long sections of the Grand Canyon into reservoirs. Eventually, Congress killed the dams. Soon afterward, Udall and his family went on a raft trip in the Grand—what he called his “ride on the wild side.”

Tom Udall told me, “My dad wanted, as he put it, to ‘let the canyons speak for themselves.’ ” For the first time, in that wild place, Stewart Udall came to appreciate why his opponents in the dam debates had felt so strongly that the river ought to be left alone. You had to see it to want to save it. He published an article soon afterward taking himself to task for his support of the dams. That year, he also travelled to upstate New York and paddled a canoe with Robert Kennedy in the Hudson River Derby, to promote the pending Wild and Scenic Rivers legislation. It passed the following year. The act now covers more than twelve thousand miles of rivers and streams, including two stretches of the Rio Grande—one in northern New Mexico and the other here on the border, beginning in the Big Bend, almost fifty miles above the Boquillas Canyon. His son wanted to hear what this canyon had to say to him.

And here we were. The walls closed in—steep, streaked limestone cliffs with a terra-cotta tinge, pocked high and low with dark openings big and small, made by waterfalls during an era, post-Ice Age, when these precincts were lush. The water, clearer here, took on the colors of the cliffs, and of the salt cedars that crowded the shore. The air had a prehistoric hush, except for the dip of paddles in the current and the tuneful descending song of the canyon wren.

The first night’s camp, called Puerto Rico, was Mile 8, river right, a broad floodplain of sand, stones, and grass. Puerto Rico was in Mexico. (After September 11th, Americans were not supposed to pull ashore, much less spend the night, on the Mexican side, but in recent years the authorities have relaxed a bit.) We set up a bucket brigade to offload the accoutrements of our portable hotel: folding tables and chairs, four-burner range, Dutch oven, propane tanks, coolers, water jugs, dozens of duffel-size dry bags, tents, and camping mattresses known as paco pads. You can carry a lot more in a boat than in a backpack. The laws of flotation allow for comfort and encourage excess. As the guides worked, the guests scattered to claim sites to pitch their tents. Dry bags spilled out domestic consolations: clean clothes, toiletries, pillows, headlamps. You could hear some light argument among spouses and siblings amid the clickety-clack of tent poles. LeRoy shooed away some grazing cattle and used a rake to remove cow dung from the prime tent spots. Udall took over for a while. Roosevelt said, “Someone has to get a picture of the Senator shovelling shit.”

Roosevelt, a seventy-five-year-old investment banker, who served in Vietnam with the Navy SEALs, was dressed like Udall, but with a Stetson hat and a red bandanna around his neck. He had a radio-friendly baritone and a solicitous air. A lifelong conservationist and Republican, by inheritance and practice, he is among those in his party who are dismayed by Trump yet are still striving, against diminishing odds, to find some workable common ground. He’s the kind of environmentalist who can acknowledge and regret the occasionally invasive and inflexible nature of a federally enforced regimen. Nonetheless, the rollbacks and predations of this Administration appall him.

In 1903, Roosevelt’s great-grandfather, as President, established the National Wildlife Refuge system, with the designation of Pelican Island, in Florida—the first instance of the federal government putting aside land for wildlife. As it happens, one of the first sections of the border wall was scheduled to be built on a national wildlife refuge in the lower Rio Grande, the Santa Ana, one of the region’s most crucial habitats for migratory birds. Last year, contractors for the Department of Homeland Security arrived there to drill test holes. Just upriver last summer, at the National Butterfly Center, a privately owned refuge, a staff member discovered a crew of workers, sent by U.S. Customs and Border Protection, on the center’s property, clearing brush and chopping down trees, in preparation for the wall, which would strand two-thirds of the center’s land on the “Mexican” side of the wall. The butterfly center has sued the federal government. “We understand that not everyone in the country may be as interested in butterflies or in the environment as we are,” the head of the center told The Texas Observer. “But everyone should care when the government thinks it can do whatever it wants on your private property.”

This is one of the reasons that the Trump Administration has been eying federal lands. Thanks to a 2005 Patriot Act provision—the REAL I.D. waiver—federal agencies were able, under the guise of national security, to ignore environmental and historic-preservation laws in building hundreds of miles of border fencing during the Bush Administration. Earlier this year, a lawsuit challenging the waiver, filed by environmental groups and the State of California, came before a federal judge in San Diego, Gonzalo Curiel. Curiel, you’ll recall, was the judge in the Trump University case whom Trump, during his campaign, had called “a hater of Donald Trump” who “happens to be, we believe, Mexican.” This time, Curiel sided with Trump.

Yet, last month, Congress, in its $1.3-trillion omnibus spending bill, essentially blocked the building of a wall through the Santa Ana refuge—for now, anyway. The bill provided hundreds of millions of dollars to enhance existing fencing and to reinforce levees on both sides but mandated a three-mile gap. (For patrollers, this is the busiest section of Texas’s southern border; they apprehended more than a hundred and thirty-seven thousand people crossing there last year, twenty-three times more than they did in the bigger but far less populous sector of the Big Bend.) Other wildlife refuges along the river were not spared. The South Texas stretch of the Rio Grande was the most affected. Still, Congress provided nowhere near the funds Trump had requested, and so in recent weeks he has started talking about deploying the military to the border, or raiding the military’s budget to fund a wall. On April 3rd, he announced that he was calling in the National Guard, though, strictly speaking, he doesn’t, as President, have the power to do so.

The kayak on the trip, which a few of us took turns paddling, was one of the vessels that had conveyed McDonald from source to sea, a few years before. It still bore traces of the messages that his wife had written all over it, in indelible ink, to keep him company. Lean, bearded, fervid, and quick-spoken, McDonald had brought along some books about the river for people to look through before dinner. He also had a photocopy of Reicher’s 1977 journal, in a freezer bag. He seemed to know more about the current state of the Rio Grande than anyone. “The Colorado, always the Colorado—it’s like the pretty girl,” he said. “The Rio Grande isn’t seen, treated, or valued as a river. My wife’s from Brownsville, and I introduced her to the Rio Grande. People think, The river is dirty, it’s poverty, it’s disease.” He was involved in efforts to address various ills, but, in light of the obstacles (and in spite of his enthusiasm), he did not evince much hope. “We have nineteenth-century laws, twentieth-century infrastructure, and twenty-first-century problems,” he liked to say. His focus, in the short term, was finding ways to get kids on the water, to introduce them to its glories, such as they are, and to begin to restore awareness of it, from the ground up.

In the thirties, Franklin D. Roosevelt’s Administration discussed a kind of anti-wall: a binational park linking public lands on the American side with millions of acres of wild country in Mexico.Photograph by George Steinmetz for The New Yorker

He pointed to the shrubs that clung to the base of the steep cliff: candelilla, a source of wax used in the production of lip balm, candles, religious figurines, and chewing gum. A hundred years ago, there was a Great Wax Rush here, with factories on both sides of the river, but now it’s a small-time affair. He described how people on the Mexican side rip the shrubs out of the soil, boil them with sulfuric acid in vats at a camp downstream, skim the wax off the surface, and then transport it by donkey out of the canyon, up to the mesa, and into Boquillas. On a good day, a candelillero can produce about ten dollars’ worth of it. “It’s either that or running a ferry,” McDonald said.

That night, after dinner (tilapia), flashes strobed above the canyon’s southern walls. “Heat lightning,” someone said, as someone usually does, and there arose a debate about whether there really is such a thing. The wind changed direction and began honking downriver. The camp seemed to be blowing apart. Then came hot pods of rain. I was determined to sleep under the stars, but after an hour of being blasted by sand, amid a light show of indeterminate origin and consequence, I gave in, and Ben Masters and I set up a tent in the dark. As we lay down, he barked, “Scorpion!” We began thrashing around, our headlamps berserking until my beam found a pale spider the size of a silver dollar, which he’d brushed from his leg. Masters got it with his water bottle, and, with the tent flaps slapping around in the wind, we settled down to a night of fitful sleep.

A river trip is a comedy of manners that commences each day with the sheepish, intermittent parade to the groover. The groover is the name of the makeshift portable latrine, which is typically set up at some remove from camp, out of sight and yet often with a stunning outlook, to make up for the flies and the lack of a stall door. It is called the groover because the body of the toilet is an old ammunition can stood on its side—on a wilderness river, you must pack everything out, including human waste, and an ammo can, being sealable and unbreakable, is ready-made—and, when one sits on it, one winds up with a groove on each cheek of one’s rear end. Usually, nowadays, a toilet seat is placed atop the opening, to moderate the experience. Still, the old moniker pertains, as does the ritual of campers competing, without demonstrating that they are doing so, to be the first, or at least among the first, to visit the groover, each day after dawn.

“I see you, Jake—but does anyone have a question that’s not about carpentry?”

Typically, there is a sign indicating that the groover is occupied—a paddle, or a bandanna on a bush. On the Rio Grande, this was a smaller ammo can, like a lunchbox, which contained paper, hand cleanser, and (for the lucky camper on groover detail) latex gloves. The smaller box’s visible presence, in a designated spot en route to the groover, indicated that the facility was free. The sight of someone carrying a lunchbox to the shit box, and the experience of cheerfully passing a fellow-boater on the way to and fro (perhaps with a tip of the hat and a “G’morning, Ma’am”), become so commonplace that, by Day Three, any stigma surrounding the procedure is gone. The groover unites us all.

This was not a topic for discussion, however, during the morning coffee conversations initiated by Reicher. The barracks banter typical of other river trips was replaced by a mediated discussion about the Rio Grande and its discontents, chief among them the wall. In the shade of the canyon, as the sunlight gradually made its way down the cliffs on the American side—there’s your wall!—Reicher asked Austin Alvarado to say a few words to the group, which was seated in a circle of folding chairs.

“The idea of a wall is so un-American to me,” Alvarado said. “Is this America first, or America only?” Alvarado, twenty-five, described how his mother, and later his father and brother—all of them Guatemalans—had crossed the river near Brownsville. Udall asked, “Austin, are you a Dreamer?”

“No, I was born here.”

Someone joked, “You say ‘here,’ but we’re in Mexico now.”

“I was born in Austin, Texas, which is how I got my name,” Alvarado said. “I have cousins who are Dreamers, though.”

“You’re called an anchor baby on the other side,” Udall said wryly.

Alvarado and Masters had spent a couple of days with Representative Will Hurd, a Republican from Texas, who strongly opposes the wall—which he has called “a third-century solution to a twenty-first-century problem.” He prefers a so-called smart wall, the deployment of camera and drone technology to trace movement on the border, especially in remote areas. You can see instances of this approach here and there in the Big Bend region; a giant unmanned blimp hovers high over the desert south of Marfa. (In the omnibus spending bill, Congress approved about two hundred million dollars that could be used for this kind of security.)

“You don’t need me. You don’t need anyone. You are Americans.”

The group began to talk about a kind of antidote to the wall, an idea that Reicher had only just heard of the month before but which has been around since Franklin D. Roosevelt’s Administration discussed it, in the thirties: a binational park, linking the existing Big Bend park and some adjacent public lands, on the American side, with millions of acres of wild country, both public and private, already set aside just across the river. The Mexican government has designated more than four million acres as protected. Cemex, the Mexican building-materials behemoth, had bought up ranches along both sides of the river, in the interest of land preservation and the reintroduction of bighorn sheep. (When Trump was elected, Cemex was assumed to be a likely provider of cement for the wall, but the company has stated that it wouldn’t be bidding on the job.) As it is, the Chihuahuan ecosystem straddles the border and exceeds the limits of any existing park. Why shouldn’t the parks and preserves be integrated somehow? One precedent is Waterton-Glacier International Peace Park, along the mountainous border between Montana and Alberta. But no one had ever thought of putting up a wall to keep out the Canadians.

The next day, we paddled eleven miles in the canyon. Several guests flipped their canoes. It doesn’t take much, once you get caught broadside against a rock in swift water. Roosevelt, in a boat with Masters, hit a submerged boulder, and into the drink they went, along with Masters’s fancy camera. Everyone had a laugh.

Camp was on the Mexican side again, just upriver of a two-pronged tower of limestone known as Rabbit Ears. Again the rituals: the load-in, the scramble for good ground, dry shorts, groover. Bob Irvin broke out a fly rod, in the hope of catching a longnose gar, a prehistoric fish native to these waters. McDonald brought out his books. There was swimming and beer-drinking in the sun, some exploration of a slot canyon, and then later, after dinner (Dutch-oven lasagna), in the dark, more Chautauqua—more schemes and dreams. Another storm blew in, and at night’s end a group of us lingered under the kitchen tarp, telling river tales. Killer holes, unfamiliar beasts, mysterious strangers. Reicher recalled finding, in a hot springs in the Lower Canyons, a new genus of isopod crustacean, one that glowed in the dark, which is unusual for a freshwater bug. He took some pickled samples back to Dartmouth and got a grant to do more research, but by the time he returned to the hot springs a flood had washed out the pools and the bugs were gone.

Masters and Alvarado told a story, from their Rio Grande adventure, about a mischievous friend of Masters’s who secretly served the two of them and a cat-loving friend an elaborate taco breakfast made with bobcat meat. I was thinking of laying out my paco pad under the tarp, but as the rain intensified a phalanx of those big pale spiders came up over the sand, eyes goggling in the beams of our headlamps. They kept converging on Masters, as though to avenge the one from the night before. We pitched a tent.

In the Grand Canyon, my friends had, after a week, got into a mode of talking to one another almost exclusively in the diction and cadence of a nineteenth-century explorer’s journals: “Cabbage stores are mostly depleted and what is left is sodden and rancid. The men grow restless.” I found myself the next morning, over pancakes and coffee, privately lapsing into it. Morale high, weather improving, Masters unbowed.

“Hey, I have an idea,” someone said.

“I have one, too,” Masters said.

“Sweet!”

“Double sweet.”

It was a bluebird morning. A tailwind, a blessing in these parts, sped us out of the canyon and into an open desert basin—out of what was, on the American side, Big Bend National Park and into the Black Gap Wildlife Management Area. (It was amazing to consider that the Big Bend park is the southern terminus, geologically speaking, of both the Appalachians and the Rockies—that the ranges, or at least the rock that distinguishes them, almost touch here.) For hours, the river tunnelled lazily through the cane and wound around until Mexico, confusingly, was to our north. We camped on that side again, along a run where Irvin spent another hour in midstream, backlit amid the riffles, as if in some fishing magazine, tossing a fly line toward the American side, to no avail—no gar. Udall passed around some Cohibas, then sat half-submerged and shirtless in an eddy, smoking one of them: a ride on the wild side. Someone put out Fritos and guacamole. A group hiked to the top of a nearby mesa just before sunset and took in hundreds of square miles of mountainous desert—a good chunk of a would-be peace park. You could also see a lot of this from the groover—of which the returning mesa hikers had an unobstructed view.

This was the first clear night, eagerly anticipated, since the area is a so-called dark-sky preserve, advantageous for gazing at the stars. The sky was soon full. After dinner (steak), a dozen or so of the group gathered by a fire and passed around a bottle of whiskey while playing what they called a drinking game, initiated by Masters: “If you were President, which fifty-mile stretch of unprotected river, anywhere in the United States, would you designate as Wild and Scenic?” One by one, people spoke of their favorite threatened waterways—the Pecos, the Pigeon, the Crow—until, under the spell of the whiskey and the stars and the rustle of the Rio Grande, it seemed possible that each pronouncement had the force of law. I slept outside and woke up with a headache. Dover’s powder depleted. The men complain of ague.

There’s something forlorn about the last run of a river trip, when you know it ends in a shuttle van rather than at a camp. A cold front washed in, bringing drizzle and a chilly headwind, and, as the flotilla passed through some slack water and a rapid that a guide called Eat Shit Rock, you could begin to see, along the banks, evidence of harder use. Abandoned infrastructure: an old mining tram, a pier improvised out of a rusting truck chassis. The big lode around here had been fluorspar. Dow Chemical once had an operation in La Linda, on the Mexican side, connected to the American side by a steel-and-concrete bridge, high above the river. This had been a busy crossing. But the mines shut down in the early nineties, and then, soon afterward, the bridge did, too, after a drug smuggler killed a Mexican customs agent. Now La Linda was a ghost town, with a ghost bridge, in the middle of the longest stretch of the river with no active border crossing.

This is where the trip came to an end, on a sandbar across from the ruins of La Linda. The vans were waiting, with trailers for the boats. Just before we got there, we passed beneath the defunct bridge, its underbelly warted up with swallows’ nests. On the roadbed above, the array of median barriers and fences, including a reinforced-mesh overhang in the shape of a backstop, brought to mind the collection of wall prototypes that Trump had recently gone to see in San Diego—the disembodied slabs that some had likened to conceptual art. Would they work? Had these? We loaded the canoes onto the trailers. From up on the bank, the river didn’t look like much. ♦

An earlier version of this article misstated the portions of the Rio Grande covered by the Wild and Scenic Rivers Act.